text:
Office of Scientific and Technical Information
Overview of Results from the National Spherical Torus Experiment (NSTX)
SciTech Connect
The mission of NSTX is the demonstration of the physics basis required to extrapolate to the next steps for the spherical torus (ST), such as a plasma facing component test facility (NHTX) or an ST based component test facility (ST-CTF), and to support ITER. Key issues for the ST are transport, and steady state high {beta} operation. To better understand electron transport, a new high-k scattering diagnostic was used extensively to investigate electron gyro-scale fluctuations with varying electron temperature gradient scale-length. Results from n = 3 braking studies confirm the flow shear dependence of ion transport. New results from electron Bernstein wave emission measurements from plasmas with lithium wall coating applied indicate transmission efficiencies near 70% in H-mode as a result of reduced collisionality. Improved coupling of High Harmonic Fast-Waves has been achieved by reducing the edge density relative to the critical density for surface wave coupling. In order to achieve high bootstrap fraction, future ST designs envision running at very high elongation. Plasmas have been maintained on NSTX at very low internal inductance l{sub i} {approx} 0.4 with strong shaping ({kappa} {approx} 2.7, {delta} {approx} 0.8) with {beta}{sub N} approaching the with-wall beta limit for several energy confinement times. By operating at lower collisionality in this regime, NSTX has achieved record non-inductive current drive fraction f{sub NI} {approx} 71%. Instabilities driven by super-Alfvenic ions are an important issue for all burning plasmas, including ITER. Fast ions from NBI on NSTX are super-Alfvenic. Linear TAE thresholds and appreciable fast-ion loss during multi-mode bursts are measured and these results are compared to theory. RWM/RFA feedback combined with n = 3 error field control was used on NSTX to maintain plasma rotation with {beta} above the no-wall limit. The impact of n > 1 error fields on stability is a important result for ITER. Other highlights are: results of lithium coating experiments, momentum confinement studies, scrape-off layer width scaling, demonstration of divertor heat load mitigation in strongly shaped plasmas, and coupling of CHI plasmas to OH ramp-up. These results advance the ST towards next step fusion energy devices such as NHTX and ST-CTF.
Gates, D; Ahn, J; Allain, J; Andre, R; Bastasz, R; Bell, M; Bell, R; Belova, E; Berkery, J; Betti, R; Bialek, J; Biewer, T; Bigelow, T; Bitter, M; Boedo, J; Bonoli, P; Bozzer, A; Brennan, D; Breslau, J; Brower, D; Bush, C; Canik, J; Caravelli, G; Carter, M; Caughman, J; Chang, C; Choe, W; Crocker, N; Darrow, D; Delgado-Aparicio, L; Diem, S; D'Ippolito, D; Domier, C; Dorland, W; Efthimion, P; Ejiri, A; Ershov, N; Evans, T; Feibush, E; Fenstermacher, M; Ferron, J; Finkenthal, M; Foley, J; Frazin, R; Fredrickson, E; Fu, G; Funaba, H; Gerhardt, S; Glasser, A; Gorelenkov, N; Grisham, L; Hahm, T; Harvey, R; Hassanein, A; Heidbrink, W; Hill, K; Hillesheim, J; Hillis, D; Hirooka, Y; Hosea, J; Hu, B; Humphreys, D; Idehara, T; Indireshkumar, K; Ishida, A; Jaeger, F; Jarboe, T; Jardin, S; Jaworski, M; Ji, H; Jung, H; Kaita, R; Kallman, J; Katsuro-Hopkins, O; Kawahata, K; Kawamori, E; Kaye, S; Kessel, C; Kim, J; Kimura, H; Kolemen, E; Krasheninnikov, S; Krstic, P; Ku, S; Kubota, S; Kugel, H; La Haye, R; Lao, L; LeBlanc, B; Lee, W; Lee, K; Leuer, J; Levinton, F; Liang, Y; Liu, D; Luhmann, N; Maingi, R; Majeski, R; Manickam, J; Mansfield, D; Maqueda, R; Mazzucato, E; McCune, D; McGeehan, B; McKee, G; Medley, S; Menard, J; Menon, M; Meyer, H; Mikkelsen, D; Miloshevsky, G; Mitarai, O; Mueller, D; Mueller, S; Munsat, T; Myra, J; Nagayama, Y; Nelson, B; Nguyen, X; Nishino, N; Nishiura, M; Nygren, R; Ono, M; Osborne, T; Pacella, D; Park, H; Park, J; Paul, S; Peebles, W; Penaflor, B; Peng, M; Phillips, C; Pigarov, A; Podesta, M; Preinhaelter, J; Ram, A; Raman, R; Rasmussen, D; Redd, A; Reimerdes, H; Rewoldt, G; Ross, P; Rowley, C; Ruskov, E; Russell, D; Ruzic, D; Ryan, P; Sabbagh, S; Schaffer, M; Schuster, E; Scott, S; Shaing, K; Sharpe, P; Shevchenko, V; Shinohara, K; Sizyuk, V; Skinner, C; Smirnov, A; Smith, D; Smith, S; Snyder, P; Soloman, W; Sontag, A; Soukhanovskii, V; Stoltzfus-Dueck, T; Stotler, D; Strait, T; Stratton, B; Stutman, D; Takahashi, R; Takase, Y; Tamura, N; Tang, X; Taylor, G; Taylor, C; Ticos, C; Tritz, K; Tsarouhas, D; Turrnbull, A; Tynan, G; Ulrickson, M; Umansky, M; Urban, J; Utergberg, E; Walker, M; Wampler, W; Wang, J; Wang, W; Weland, A
PPPL-3445 PPPL-3445 National Spherical Torus Experiment (NSTX)
E-Print Network (OSTI)
such as the pilot and power plants. The NSTX device began the plasma operations in February 1999 and the plasma (Coaxial Helicity Injection) and HHFW (High Harmonic Fast Wave) experiments have also started. Stable CHI eight antennas connected to two transmitters, up to 2 MW of HHFW power was successfully coupled
Progress towards Steady State at Low Aspect Ratio on the National Spherical Torus Experiment (NSTX)
Modifications to the plasma control capabilities and poloidal field coils of the National Spherical Torus Experiment (NSTX) have enabled a significant enhancement in shaping capability which has led to the transient achievement of a record shape factor (S ? q95 (I?? ???)) of ?41 (MA m?1 ??1) simultaneous with a record plasma elongation of ? ? ? ? ? ? 3. This result was obtained using isoflux control and real-time equilibrium reconstruction. Achieving high shape factor together with tolerable divertor loading is an important result for future ST burning plasma experiments as exemplified by studies for future ST reactor concepts, as well as neutron producing devices, which rely on achieving high shape factors in order to achieve steady state operation while maintaining MHD stability. Statistical evidence is presented which demonstrates the expected correlation between increased shaping and improved plasma performance.
D.A. Gates, J. Menard, R. Maingi, S. Kaye, S.A. Sabbagh, S. Diem, J.R.Wilson, M.G. Bell, R.E. Bell, J. Ferron, E.D. Fredrickson, C.E. Kessel, B.P. LeBlanc, F. Levinton, J. Manickam, D. Mueller, R. Raman, T. Stevenson, D. Stutman, G. Taylor, K. Tritz, H. Yu, and the NSTX Research Team
EBW-Bootstrap Current Synergy in the National Spherical Torus Experiment (NSTX)
Current driven by electron Bernstein waves (EBW) and by the electron bootstrap effect are calculated separately and concurrently with a kinetic code, to determine the degree of synergy between them. A target {beta} = 40% NSTX plasma is examined. A simple bootstrap model in the CQL3D Fokker-Planck code is used in these studies: the transiting electron distributions are connected in velocity-space at the trapped-passing boundary to trapped-electron distributions which are displaced radially by a half-banana width outwards/inwards for the co-/counter-passing regions. This model agrees well with standard bootstrap current calculations, over the outer 60% of the plasma radius. Relatively small synergy net bootstrap current is obtained for EBW power up to 4 MW. Locally, bootstrap current density increases in proportion to increased plasma pressure, and this effect can significantly affect the radial profile of driven current.
R.W. Harvey; G. Taylor
Detection of Disruptions in the High-? Spherical Torus NSTX
This paper describes the prediction of disruptions based on diagnostic data in the high-? spherical torus NSTX [M. Ono, et al., Nuclear Fusion 40 , 557 (2000)]. The disruptive threshold values on many signals are examined. In some cases, raw diagnostic data can be used as a signal for disruption prediction. In others, the deviations of the plasma data from simple models provides the signal used to determine the proximity to disruption. However, no single signal and threshold value can form the basis for disruption prediction in NSTX; thresholds that produce an acceptable false positive rate have too large a missed or late warning rate, while combinations that produce an acceptable rate of missed or late warnings have an unacceptable false positive rate. To solve this problem, a novel means of combining multiple threshold tests has been developed. After being properly tuned, this algorithm can produce a false positive rate of 2.8%, with a late warning rate of 3.7% when applied to a database of ~2000 disruptions collected from three run campaigns. Furthermore, many of these false positives are triggered by near-disruptive MHD events that might indeed be disruptive in larger plasmas with more stored energy. However, the algorithm is less efficient at detecting the MHD event that prompts the disruption process.
Gerhardt, S P; Bell, R E; LeBlanc, B P; Menard, J E; Mueller, D; Roquemore, A L; Sabbagh, S A
Ohmic Flux Consumption During Initial Operation of the NSTX Spherical Torus
.5, vacuum toroidal field B T = 0.3 Tesla at R 0 , plasma current I P current and flattop duration achievable with these fluxes. Two di#erent methods have been used previOhmic Flux Consumption During Initial Operation of the NSTX Spherical Torus J. Menard 1 , B. Le
Spherical Torus Center Stack Design
The low aspect ratio spherical torus (ST) configuration requires that the center stack design be optimized within a limited available space, using materials within their established allowables. This paper presents center stack design methods developed by the National Spherical Torus Experiment (NSTX) Project Team during the initial design of NSTX, and more recently for studies of a possible next-step ST (NSST) device.
C. Neumeyer; P. Heitzenroeder; C. Kessel; M. Ono; M. Peng; J. Schmidt; R. Woolley; I. Zatz
Disruptions, Disruptivity, and Safer Operating Windows in the High-? Spherical Torus NSTX
This paper discusses disruption rates, disruption causes, and disruptivity statistics in the high- ?N National Spherical Torus Experiment (NSTX) [M. Ono, et al. Nuclear Fusion 40, 557 (2000)]. While the overall disruption rate is rather high, configurations with high ?N , moderate q*, strong boundary shaping, sufficient rotation, and broad pressure and current profiles are found to have the lowest disruptivity; active n=1 control further reduces the disruptivity. The disruptivity increases rapidly for q*<2.7, which is substantially above the ideal MHD current limit. In quiescent conditions, qmin >1.25 is generally acceptable for avoiding the onset of core rotating n=1 kink/tearing modes; when EPM and ELM disturbances are present, the required qmin for avoiding those modes is raised to ~1.5. The current ramp and early flat-top phase of the discharges are prone to n=1 core rotating modes locking to the wall, leading to a disruption. Small changes to the discharge fueling during this phase can often mitigate the rotation damping associated with these modes and eliminate the disruption. The largest stored energy disruptions are those that occur at high current when a plasma current rampdown is initiated incorrectly.
Gerhardt, S P; Diallo, A; Gates, D; LeBlanc, B P; Menard, J E; Mueller, D; Sabbagh, S A; Soukhanovskii, V; Tritz, K
National Spherical Torus Experiment (NSTX) | Princeton Plasma...
NLE Websites -- All DOE Office Websites (Extended Search)
Join Our Mailing List A Collaborative National Center for Fusion & Plasma Research Search form Search Search Home About Overview Learn More Visiting PPPL History...
Control System Development Plan for the National Spherical Torus Experiment
The National Spherical Torus Experiment (NSTX) has as one of its primary goals the demonstration of the attractiveness of the spherical torus concept as a fusion power plant. Central to this goal is the achievement of high plasma {beta} ( = 2{micro}{sub 0}
/B{sup 2} a measure of the efficiency of a magnetic plasma confinement system). It has been demonstrated both theoretically and experimentally that the maximum achievable {beta} is a strong function of both local and global plasma parameters. It is therefore important to optimize control of the plasma. To this end a phased development plan for digital plasma control on NSTX is presented. The relative level of sophistication of the control system software and hardware will be increased according to the demands of the experimental program in a three phase plan. During Day 0 (first plasma), a simple coil current control algorithm will initiate plasma operations. During the second phase (Day 1) of plasma operations the control system will continue to use the preprogrammed algorithm to initiate plasma breakdown but will then change over to a rudimentary plasma control scheme based on linear combinations of measured plasma fields and fluxes. The third phase of NSTX plasma control system development will utilize the rtEFIT code, first used on DIII-D, to determine, in real-time, the full plasma equilibrium by inverting the Grad-Shafranov equation. The details of the development plan, including a description of the proposed hardware will be presented.
C. Neumeyer; D. Mueller; D.A. Gates; J.R. Ferron
Electron Bernstein Wave Research on the National Spherical Torus Experiment
Off-axis electron Bernstein wave current drive (EBWCD) may be critical for sustaining noninductive high-beta National Spherical Torus Experiment (NSTX) plasmas. Numerical modeling results predict that the {approx}100 kA of off-axis current needed to stabilize a solenoid-free high-beta NSTX plasma could be generated via Ohkawa current drive with 3 MW of 28 GHz EBW power. In addition, synergy between EBWCD and bootstrap current may result in a 10% enhancement in current-drive efficiency with 4 MW of EBW power. Recent dual-polarization EBW radiometry measurements on NSTX confirm that efficient coupling to EBWs can be readily accomplished by launching elliptically polarized electromagnetic waves oblique to the confining magnetic field, in agreement with numerical modeling. Plans are being developed for implementing a 1 MW, 28 GHz proof-of-principle EBWCD system on NSTX to test the EBW coupling, heating and current-drive physics at high radio-frequency power densities.
G. Taylor; A. Bers; T.S. Bigelow; M.D. Carter; J.B. Caughman; J. Decker; S. Diem; P.C. Efthimion; N.M. Ershov; E. Fredd; R.W. Harvey; J. Hosea; F. Jaeger; J. Preinhaelter; A.K. Ram; D.A. Rasmussen; A.P. Smirnov; J.B. Wilgen; J.R. Wilson
Making of the NSTX Facility
The NSTX (National Spherical Torus Experiment) facility located at Princeton Plasma Physics Laboratory is the newest national fusion science experimental facility for the restructured US Fusion Energy Science Program. The NSTX project was approved in Fy 97 as the first proof-of-principle national fusion facility dedicated to the spherical torus research. On Feb. 15, 1999, the first plasma was achieved 10 weeks ahead of schedule. The project was completed on budget and with an outstanding safety record. This paper gives an overview of the NSTX facility construction and the initial plasma operations.
Ono, M. [Princeton Plasma Physics Laboratory (PPPL); Peng, Yueng Kay Martin [ORNL
Physics results from the National Spherical Torus Experiment
The National Spherical Torus Experiment (NSTX) at the Princeton Plasma Physics Laboratory is designed for studying toroidal plasma confinement at very low aspect-ratio, A=R/a = 0.85m/0.68m {approximately} 1.25, with cross-section elongation up to 2.2 and triangularity up to 0.5, for plasma currents up to 1 MA and vacuum toroidal magnetic fields up to 0.6 T on axis. Conducting plates are installed close to the plasma on the outboard side to stabilize kink modes. This should permit operation with toroidal-{beta} approaching 40%. The plasmas will be heated by up to 6 MW High-Harmonic Fast Waves (HHFW) at a frequency 30 MHz and by 5 MW of 80 keV deuterium Neutral Beam Injection. Inductive plasma startup can be supplemented by the process of Coaxial Helicity Injection (CHI).
M.G. Bell
The NSTX Trouble Reporting System
Science Conference Proceedings (OSTI)
An online Trouble Reporting System (TRS) has been introduced at the National Spherical Torus Experiment (NSTX). The TRS is used by NSTX operators to report problems that affect NSTX operations. The purpose of the TRS is to enhance NSTX reliability and maintainability by identifying components, occurrences, and trends that contribute to machine downtime. All NSTX personnel have access to the TRS. The user interface is via a web browser, such as Netscape or Internet Explorer. This web-based feature permits any X-terminal, PC, or MAC access to the TRS. The TRS is based upon a trouble reporting system developed at the DIII-D Tokamak, at General Atomics Technologies. This paper will provide a detailed description of the TRS software architecture, user interface, MS SQL server interface and operational experiences. In addition, sample data from the TRS database will be summarized and presented.
S. Sengupta; G. Oliaro
Hardwired Control Changes For NSTX DC Power Feeds
The National Spherical Torus Experiment (NSTX) has been designed and installed in the existing facilities at Princeton Plasma Physics Laboratory (PPPL). Most of the hardware, plant facilities, auxiliary sub-systems, and power systems originally used for the Tokamak Fusion Test Reactor (TFTR) have been used with suitable modifications to reflect NSTX needs. The original TFTR Hardwired Control System (HCS) with electromechanical relays was used for NSTX DC Power loop control and protection during NSTX operations. As part of the NSTX Upgrade, the HCS is being changed to a PLC-based system with the same control logic. This paper gives a description of the changeover to the new PLC-based system __________________________________________________
Ramakrishnan, S.
Exploration of High Harmonic Fast Wave Heating on the National Spherical Torus Experiment
High Harmonic Fast Wave (HHFW) heating has been proposed as a particularly attractive means for plasma heating and current drive in the high-beta plasmas that are achievable in spherical torus (ST) devices. The National Spherical Torus Experiment (NSTX) [Ono, M., Kaye, S.M., Neumeyer, S., et al., Proceedings, 18th IEEE/NPSS Symposium on Fusion Engineering, Albuquerque, 1999, (IEEE, Piscataway, NJ (1999), p. 53.)] is such a device. An radio-frequency (rf) heating system has been installed on NSTX to explore the physics of HHFW heating, current drive via rf waves and for use as a tool to demonstrate the attractiveness of the ST concept as a fusion device. To date, experiments have demonstrated many of the theoretical predictions for HHFW. In particular, strong wave absorption on electrons over a wide range of plasma parameters and wave parallel phase velocities, wave acceleration of energetic ions, and indications of current drive for directed wave spectra have been observed. In addition HHFW heating has been used to explore the energy transport properties of NSTX plasmas, to create H-mode (high-confinement mode) discharges with a large fraction of bootstrap current and to control the plasma current profile during the early stages of the discharge.
J.R. Wilson; R.E. Bell; S. Bernabei; M. Bitter; P. Bonoli; D. Gates; J. Hosea; B. LeBlanc; T.K. Mau; S. Medley; J. Menard; D. Mueller; M. Ono; C.K. Phillips; R.I. Pinsker; R. Raman; A. Rosenberg; P. Ryan; S. Sabbagh; D. Stutman; D. Swain; Y. Takase; J. Wilgen; the NSTX Team
Physics Design of a 28 GHz Electron Heating System for the National Spherical Torus Experiment Upgrade
A megawatt-level, 28 GHz electron heating system is being designed to support non-inductive (NI) plasma current (I{sub p}) start-up and local heating and current drive (CD) in H-mode discharges in the National Spherical Torus Experiment Upgrade (NSTX-U). The development of fully NI I{sub p} start-up and ramp-up is an important goal of the NSTX-U research program. 28 GHz electron cyclotron (EC) heating is predicted to rapidly increase the central electron temperature (T{sub e}(0)) of low density NI plasmas generated by Coaxial Helicity Injection (CHI). The increased T{sub e}(0) will significantly reduce the Ip decay rate of CHI plasmas, allowing the coupling of fast wave heating and neutral beam injection. Also 28 GHz electron Bernstein wave (EBW) heating and CD can be used during the I{sub p} flat top in NSTX-U discharges when the plasma is overdense. Ray tracing and Fokker-Planck numerical simulation codes have been used to model EC and EBW heating and CD in NSTX-U. This paper presents a pre-conceptual design for the 28 GHz heating system and some of the results from the numerical simulations.
Scintillator Based Energetic Ion Loss Diagnostic for the National Spherical Torus Experiment
A scintillator based energetic ion loss detector has been built and installed on the National Spherical Torus Experiment (NSTX) to measure the loss of neutral beam ions. The detector is able to resolve the pitch angle and gyroradius of the lost energetic ions. It has a wide acceptance range in pitch angle and energy, and is able to resolve the full, one-half, and one-third energy components of the 80 keV D neutral beams up to the maximum toroidal magnetic field of NSTX. Multiple Faraday cups have been embedded behind the scintillator to allow easy absolute calibration of the diagnostic and to measure the energetic ion loss to several ranges of pitch angle with good time resolution. Several small, vacuum compatible lamps allow simple calibration of the scintillator position within the field of view of the diagnostic's video camera.
D.S. Darrow
Fast-ion Energy Loss During TAE Avalanches in the National Spherical Torus Experiment
Strong TAE avalanches on NSTX, the National Spherical Torus Experiment [M. Ono, et al., Nucl. Fusion 40 (2000) 557] are typically correlated with drops in the neutron rate in the range of 5% - 15%. In previous studies of avalanches in L-mode plasmas, these neutron drops were found to be consistent with modeled losses of fast ions. Here we expand the study to TAE avalanches in NSTX H-mode plasmas with improved analysis techniques. At the measured TAE mode amplitudes, simulations with the ORBIT code predict that fast ion losses are negligible. However, the simulations predict that the TAE scatter the fast ions in energy, resulting in a small (? 6%) drop in fast ion ?. The net decrease in energy of the fast ions is sufficient to account for the bulk of the drop in neutron rate, even in the absence of fast ion losses. This loss of energy from the fast ion population is comparable to the estimated energy lost by damping from the Alfven wave during the burst. The previously studied TAE avalanches in L-mode are re-evaluated using an improved calculation of the potential fluctuations in the ORBIT code.
Fredrickson, E D; Darrow, D S; Gorelenkov, N N; Kramer, G J; Kubota, S; Podesta, M; White, R B; Bortolon, A; Gerhardt, S P; Bell, R E; Diallo, A; LeBlanc, B; Levinton, F M
Ramp-up of CHI Initiated Plasmas on NSTX
Experiments on the National Spherical Torus (NSTX) have now demonstrated flux savings using transient coaxial helicity injection (CHI). In these discharges, the discharges initiated by CHI are ramped up with an inductive transformer and exhibit higher plasma current than discharges without the benefit of CHI initiation.
Mueller, D; Bell, R E; LeBlanc, B; Roquemore, A L; Raman, R; Jarboe, T R; Nelson, B A
NSTX Diagnostics and Operation: Status and Plans
The low aspect ratio and low magnetic field of the National Spherical Torus Experiment (NSTX) create many challenges for plasma diagnostics and control, as well as opportunities for studying new plasma phenomena. This paper describes the diagnostics now installed for studies of confinement, stability and edge plasma phenomena, and some of the diagnostic developments planned for the near future. The design of the plasma control system and plans for its development are also presented.
M.G. Bell; R.E. Bell; B.P. LeBlanc; S.S. Medley; and the NSTX Research Team
Neutral Particle Analyzer Diagnostic on NSTX
DOE Green Energy (OSTI)
The Neutral Particle Analyzer (NPA) diagnostic on the National Spherical Torus Experiment (NSTX) utilizes a PPPL-designed E||B spectrometer that measures the energy spectra of minority hydrogen and bulk deuterium species simultaneously with 39 energy channels per mass specie and a time resolution of 1 ms. The calibrated energy range is E = 0.5-150 keV and the energy resolution varies from AE/E = 3-7% over the surface of the microchannel plate detector.
S.S. Medley; A.L. Roquemore
Dynamical Evolution of Pedestal Parameters in ELMy H-mode in the National Spherical Torus Experiment
Characterizations of the pedestal parameter dynamics throughout the edge localized modes(ELM) cycles are performed on the National Spherical Torus Experiment (NSTX, [M. Ono et al., Nucl. Fusion 40, 557 (2000)]). A clear buildup of the pedestal height is observed between ELMs for three di erent plasma currents, which tends to saturate prior to the onset of ELM at low and medium plasma current. Similarly, the pedestal width increases with no clear evidence of saturation during an ELM cycle. The maximum pedestal gradient increases as a function of plasma current, reaches a nominal value after the ELM crash, and remains constant until the end of the ELM cycle. The pedestal height just prior to the onset of ELM is shown to increase quadratically with plasma current. The pedestal width ? is proportional to the square-root of the poloidal ? at the top of the pedestal. Coherent density uctuations strongly increasing at the plasma edge are observed to be maximum after the ELM crash and to decay during the rest of the ELM cycle. Finally, the pedestal parameters evolution during the ELM cycle as well as the scaling with Ip of the pedestal pressure prior to the onset ELM are found to be qualitatively consistent with the peeling ballooning theory.
Diallo, A; Kubota, S; Sontag, A; Osborne, T; Podesta, M; Bell, R E; LeBlanc, B P; Menard, J
Next-Step Spherical Torus Experiment and Spherical Torus Strategy in the Fusion Energy Development Path
A spherical torus (ST) fusion energy development path which is complementary to proposed tokamak burning plasma experiments such as ITER is described. The ST strategy focuses on a compact Component Test Facility (CTF) and higher performance advanced regimes leading to more attractive DEMO and Power Plant scale reactors. To provide the physics basis for the CTF an intermediate step needs to be taken which we refer to as the ''Next Step Spherical Torus'' (NSST) device and examine in some detail herein. NSST is a ''performance extension'' (PE) stage ST with the plasma current of 5-10 MA, R = 1.5 m, and Beta(sub)T less than or equal to 2.7 T with flexible physics capability. The mission of NSST is to: (1) provide a sufficient physics basis for the design of CTF, (2) explore advanced operating scenarios with high bootstrap current fraction/high performance regimes, which can then be utilized by CTF, DEMO, and Power Plants, and (3) contribute to the general plasma/fusion science of high beta toroidal plasmas. The NSST facility is designed to utilize the Tokamak Fusion Test Reactor (or similar) site to minimize the cost and time required for the design and construction.
M. Ono; M. Peng; C. Kessel; C. Neumeyer; J. Schmidt; J. Chrzanowski; D. Darrow; L. Grisham; P. Heitzenroeder; T. Jarboe; C. Jun; S. Kaye; J. Menard; R. Raman; T. Stevenson; M. Viola; J. Wilson; R. Woolley; I. Zatz
Progress towards Steady State on NSTX
In order to reduce recirculating power fraction to acceptable levels, the spherical torus concept relies on the simultaneous achievement of high toroidal {beta} and high bootstrap fraction in steady state. In the last year, as a result of plasma control system improvements, the achievable plasma elongation on the National Spherical Torus Experiment (NSTX) has been raised from {kappa} {approx} 2.1 to {kappa} {approx} 2.6--approximately a 25% increase. This increase in elongation has lead to a doubling increase in the toroidal {beta} for long-pulse discharges. The increase in {beta} is associated with an increase in plasma current at nearly fixed poloidal {beta}, which enables higher {beta}{sub t} with nearly constant bootstrap fraction. As a result, for the first time in a spherical torus, a discharge with a plasma current of 1 MA has been sustained for 1 second. Data is presented from NSTX correlating the increase in performance with increased plasma shaping capability. In addition to improved shaping, H-modes induced during the current ramp phase of the plasma discharge have been used to reduce flux consumption during and to delay the onset of MHD instabilities. A modeled integrated scenario, which has 100% non-inductive current drive with very high toroidal {beta}, will also be presented. The NSTX poloidal field coils are currently being modified to produce the plasma shape which is required for this scenario, which requires high triangularity ({delta} {approx} 0.8) at elevated elongation ({kappa} {approx} 2.5). The other main requirement for steady state on NSTX is the ability to drive a fraction of the total plasma current with radio-frequency waves. The results of High Harmonic Fast Wave heating and current drive studies as well as electron Bernstein Wave emission studies will be presented.
D.A. Gates; C. Kessel; J. Menard; G. Taylor; J.R. Wilson; plus 94 co-authors
Analysis Efforts Supporting NSTX Upgrades
The National Spherical Torus Experiment (NSTX) is a low aspect ratio, spherical torus (ST) configuration device which is located at Princeton Plasma Physics Laboratory (PPPL) This device is presently being updated to enhance its physics by doubling the TF field to 1 Tesla and increasing the plasma current to 2 Mega-amperes. The upgrades include a replacement of the centerstack and addition of a second neutral beam. The upgrade analyses have two missions. The first is to support design of new components, principally the centerstack, the second is to qualify existing NSTX components for higher loads, which will increase by a factor of four. Cost efficiency was a design goal for new equipment qualification, and reanalysis of the existing components. Showing that older components can sustain the increased loads has been a challenging effort in which designs had to be developed that would limit loading on weaker components, and would minimize the extent of modifications needed. Two areas representing this effort have been chosen to describe in more details: analysis of the current distribution in the new TF inner legs, and, second, analysis of the out-of-plane support of the existing TF outer legs.
H.Zhang, P. Titus, P. Rogoff, A.Zolfaghari, D. Mangra, M. Smith
Off-axis electron Bernstein wave current drive (EBWCD) may be critical for sustaining non-inductive high ? NSTX plasmas. Numerical modeling results predict that the ~ 100 kA of offaxis current needed to stabilize a solenoid-free high ? NSTX plasma could be generated via Ohkawa CD with 3 MW of 28 GHz EBW power. In addition, synergy between EBWCD and bootstrap current may result in a 10% enhancement in CD efficiency with 4 MW of EBW power. Recent dualpolarization EBW radiometry measurements on NSTX confirm that efficient coupling to EBWs can be readily accomplished by launching elliptically polarized electromagnetic waves oblique to the confining magnetic field, in agreement with numerical modeling. Plans are being developed for implementing a 1 MW, 28 GHz proof-of-principle EBWCD system on NSTX to test the EBW coupling, heating and CD physics at high rf power densities.
Taylor, G. [Princeton Plasma Physics Laboratory (PPPL); Bers, A. [Massachusetts Institute of Technology (MIT); Bigelow, Tim S [ORNL; Carter, Mark Dwain [ORNL; Caughman, John B [ORNL; Decker, J. [Massachusetts Institute of Technology (MIT); Diem, S. [Princeton Plasma Physics Laboratory (PPPL); Efthimion, P. C. [Princeton Plasma Physics Laboratory (PPPL); Ershov, N. M. [Moscow State University; Fredd, E. [Princeton Plasma Physics Laboratory (PPPL); Harvey, R. W. [CompX, Del Mar, CA; Hosea, J. [Princeton Plasma Physics Laboratory (PPPL); Jaeger, F. [Oak Ridge National Laboratory (ORNL); Preinhaelter, J. [Institute of Plasma Physics, Prague, Czech Republic; Ram, A. K. [Massachusetts Institute of Technology (MIT); Rasmussen, David A [ORNL; Smirnov, A. [Moscow State University; Wilgen, John B [ORNL; Wilson, J. R. [Princeton Plasma Physics Laboratory (PPPL)
Plasma Response to Lithium-Coated Plasma-Facing Components in the National Spherical Torus Experiment
Experiments in the National Spherical Torus Experiment (NSTX) have shown beneficial effects on the performance of divertor plasmas as a result of applying lithium coatings on the graphite and carbonfiber- composite plasma-facing components. These coatings have mostly been applied by a pair of lithium evaporators mounted at the top of the vacuum vessel which inject collimated streams of lithium vapor towards the lower divertor. In NBI-heated, deuterium H-mode plasmas run immediately after the application of lithium, performance modifications included decreases in the plasma density, particularly in the edge, and inductive flux consumption, and increases in the electron and ion temperatures and the energy confinement time. Reductions in the number and amplitude of ELMs were observed, including complete ELM suppression for periods up to 1.2 s, apparently as a result of altering the stability of the edge. However, in the plasmas where ELMs were suppressed, there was a significant secular increase in the effective ion charge Zeff and the radiated power as a result of increases in the carbon and medium-Z metallic impurities, although not of lithium itself which remained at a very low level in the plasma core, lithium also inhibited parasitic losses through the scrape-off layer of ICRF power coupled to the plasma, enabling the waves to heat electrons in the core of H-mode plasmas produced by NBI. Lithium has also been introduced by injecting a stream of chemically stabilized, fine lithium powder directly into the scrape-off layer of NBI-heated plasmas. The lithium was ionized in the SOL and appeared to flow along the magnetic field to the divertor plates. This method of coating produced similar effects to the evaporated lithium but at lower amounts.
M.G. Bell, H.W. Kugel, R. Kaita, L.E. Zakharov, H. Schneider, B.P. LeBlanc, D. Mansfield, R.E. Bell, R. Maingi, S. Ding, S.M. Kaye, S.F. Paul, S.P. Gerhardt, J.M. Canik, J.C. Hosea, G. Taylor and the NSTX Research Team
A Neutral Beam Injector Upgrade for NSTX
The National Spherical Torus Experiment (NSTX) capability with a Neutral Beam Injector (NBI) capable of 80 kiloelectronvolt (keV), 5 Megawatt (MW), 5 second operation. This 5.95 million dollar upgrade reused a previous generation injector and equipment for technical, cost, and schedule reasons to obtain these specifications while retaining a legacy capability of 120 keV neutral particle beam delivery for shorter pulse lengths for possible future NSTX experiments. Concerns with NBI injection included power deposition in the plasma, aiming angles from the fixed NBI fan array, density profiles and beam shine through, orbit losses of beam particles, and protection of the vacuum vessel wall against beam impingement. The upgrade made use of the beamline and cryo panels from the Neutral Beam Test Stand facility, existing power supplies and controls, beamline components and equipment not contaminated by tritium during DT [deuterium-tritium] experiments, and a liquid Helium refrigerator plant to power and cryogenically pump a beamline and three ion sources. All of the Tokamak Fusion Test Reactor (TFTR) ion sources had been contaminated with tritium, so a refurbishment effort was undertaken on selected TFTR sources to rid the three sources destined for the NSTX NBI of as much tritium as possible. An interconnecting duct was fabricated using some spare and some new components to attach the beamline to the NSTX vacuum vessel. Internal vacuum vessel armor using carbon tiles was added to protect the stainless steel vacuum vessel from beam impingement in the absence of plasma and interlock failure. To date, the NBI has operated to 80 keV and 5 MW and has injected requested power levels into NSTX plasmas with good initial results, including high beta and strong heating characteristics at full rated plasma current.
T. Stevenson; B McCormack; G.D. Loesser; M. Kalish; S. Ramakrishnan; L. Grisham; J. Edwards; M. Cropper; G. Rossi; A. von Halle; M. Williams
Comparison of Gas Puff Imaging Data in NSTX with the DEGAS 2 Simulation
Gas-Pu -Imaging (GPI) is a two dimensional diagnostic which measures the edge D? light emission from a neutral D? gas puff near the outer mid- plane of the National Spherical Torus Experiment (NSTX). DEGAS 2 is a 3-D Monte Carlo code used to model neutral transport and plasma-neutral interactions in fusion plasmas. In this paper, we compare the measured and modeled D? light emission for speci c NSTX experiments. Both the simulated spatial distribution and radiance of the D? light emission agree well with the experimental data obtained between Edge Localized Modes (ELMs) in ELMy H-modes.
B. Cao, D.P. Stotler, S.J. Zweben, M. Bell, A.Diallo, B. LeBlanc
Final Design Review (FDR) Committee Report National Spherical Torus Experiment
prepared as required by DOE 413.3B? · CD-3 checkpoint documentation per DOE 413.3B is currently being identified and currently being prepared as required by DOE 413.3B? 9. Outage planning and coordination - Has. Does the final design meet the requirements for the NSTX Upgrade Project as delineated in the General
Princeton Plasma Physics Laboratory
Power Supply Changes for NSTX Resistive Wall Mode Coils
The National Spherical Torus Experiment (NSTX) has been designed and installed in the existing facilities at Princeton Plasma Physics Laboratory (PPPL). Most of the hardware, plant facilities, auxiliary sub-systems, and power systems originally used for the Tokamak Fusion Test Reactor (TFTR) have been used with suitable modifications to reflect NSTX needs. Prior to 2004, the NSTX power system was feeding twelve (12) circuits in the machine. In 2004 the Resistive Wall Mode (RWM) Coils were installed on the machine to correct error fields. There are six of these coils installed around the machine in the mid-plane. Since these coils need fast and accurate controls, a Switching Power Amplifier (SPA) with three sub-units was procured, installed and commissioned along with other power loop components. Two RWM Coils were connected in series and fed from one SPA sub-unit. After the initial RWM campaign, operational requirements evolved such that each of the RWM coils now requires separate power and control. Hence a second SPA with three sub-units has been procured and installed. The second unit is of improved design and has the controls and power components completely isolated. The existing thyristor rectifier is used as DC Link to both of the Switching Power Amplifiers. The controls for the RWM are integrated into the overall computer control of the DC Power systems for NSTX. This paper describes the design changes in the RWM Power system for NSTX.
Ramakrishnan, S S.
High Harmonic Fast Wave Heating Efficiency Enhancemen and Current Drive at Longer Wavelength on the National Spherical Torus Experiment
High harmonic fast wave heating and current drive (CD) are being developed on the National Spherical Torus Experiment (NSTX) [M. Ono et al., Nucl. Fusion 41, 1435 (2001)] for supporting startup and sustainment of the ST plasma. Considerable enhancement of the core heating efficiency (?) from 44% to 65% has been obtained for CD phasing of the antenna (strap-to-strap ? = -90o, k? = -8 m-1) by increasing the magnetic field from 4.5 kG to 5.5 kG. This increase in efficiency is strongly correlated to moving the location of the onset density for perpendicular fast wave propagation (nonset ? ??� k|| 2/w) away from the antenna face and wall, and hence reducing the propagating surface wave fields. RF waves propagating close to the wall at lower B? and k|| can enhance power losses from both the parametric decay instability (PDI) and wave dissipation in sheaths and structures around the machine. The improved efficiency found here is attributed to a reduction in the latter, as PDI losses are little changed at the higher magnetic field. Under these conditions of higher coupling efficiency, initial measurements of localized CD effects have been made and compared with advanced RF code simulations
J. Hosea, R. E. Bell, B.P. LeBlanc, C.K. Phillips, G. Taylor, E. Valeo, J.R. Wilson, E.F. Jaeger, P.M. Ryan, J. Wilgen, H. Yuh, F. Levinton, S. Sabbagh, K. Tritz, J. Parker, P.T. Bonoli, R. Harvey, and the NSTX Team
Progress Towards High Performance, Steady-state Spherical Torus
Research on the Spherical Torus (or Spherical Tokamak) is being pursued to explore the scientific benefits of modifying the field line structure from that in more moderate aspect-ratio devices, such as the conventional tokamak. The Spherical Tours (ST) experiments are being conducted in various U.S. research facilities including the MA-class National Spherical Torus Experiment (NSTX) at Princeton, and three medium-size ST research facilities: Pegasus at University of Wisconsin, HIT-II at University of Washington, and CDX-U at Princeton. In the context of the fusion energy development path being formulated in the U.S., an ST-based Component Test Facility (CTF) and, ultimately a Demo device, are being discussed. For these, it is essential to develop high-performance, steady-state operational scenarios. The relevant scientific issues are energy confinement, MHD stability at high beta (B), noninductive sustainment, ohmic-solenoid-free start-up, and power and particle handling. In the confinement area, the NSTX experiments have shown that the confinement can be up to 50% better than the ITER-98-pby2 H-mode scaling, consistent with the requirements for an ST-based CTF and Demo. In NSTX, CTF-relevant average toroidal beta values bT of up to 35% with the near unity central betaT have been obtained. NSTX will be exploring advanced regimes where bT up to 40% can be sustained through active stabilization of resistive wall modes. To date, the most successful technique for noninductive sustainment in NSTX is the high beta-poloidal regime, where discharges with a high noninductive fraction ({approx}60% bootstrap current + neutral-beam-injected current drive) were sustained over the resistive skin time. Research on radio-frequency-based heating and current drive utilizing HHFW (High Harmonic Fast Wave) and EBW (Electron Bernstein Wave) is also pursued on NSTX, Pegasus, and CDX-U. For noninductive start-up, the Coaxial Helicity Injection (CHI), developed in HIT/HIT-II, has been adopted on NSTX to test the method up to Ip {approx} 500 kA. In parallel, start-up using radio-frequency current drive and only external poloidal field coils are being developed on NSTX. The area of power and particle handling is expected to be challenging because of the higher power density expected in the ST relative to that in conventional aspect-ratio tokamaks. Due to its promise for power and particle handling, liquid lithium is being studied in CDX-U as a potential plasma-facing surface for a fusion reactor.
M. Ono; M.G. Bell; R.E. Bell; T. Bigelow; M. Bitter; W. Blanchard; J. Boedo; C. Bourdelle; C. Bush; W. Choe; J. Chrzanowski; D.S. Darrow; S.J. Diem; R. Doerner; P.C. Efthimion; J.R. Ferron; R.J. Fonck; E.D. Fredrickson; G.D. Garstka; D.A. Gates; T. Gray; L.R. Grisham; W. Heidbrink; K.W. Hill; D. Hoffman; T.R. Jarboe; D.W. Johnson; R. Kaita; S.M. Kaye; C. Kessel; J.H. Kim; M.W. Kissick; S. Kubota; H.W. Kugel; B.P. LeBlanc; K. Lee; S.G. Lee; B.T. Lewicki; S. Luckhardt; R. Maingi; R. Majeski; J. Manickam; R. Maqueda; T.K. Mau; E. Mazzucato; S.S. Medley; J. Menard; D. Mueller; B.A. Nelson; C. Neumeyer; N. Nishino; C.N. Ostrander; D. Pacella; F. Paoletti; H.K. Park; W. Park; S.F. Paul; Y.-K. M. Peng; C.K. Phillips; R. Pinsker; P.H. Probert; S. Ramakrishnan; R. Raman; M. Redi; A.L. Roquemore; A. Rosenberg; P.M. Ryan; S.A. Sabbagh; M. Schaffer; R.J. Schooff; R. Seraydarian; C.H. Skinner; A.C. Sontag; V. Soukhanovskii; J. Spaleta; T. Stevenson; D. Stutman; D.W. Swain; E. Synakowski; Y. Takase; X. Tang; G. Taylor; J. Timberlake; K.L. Tritz; E.A. Unterberg; A. Von Halle; J. Wilgen; M. Williams; J.R. Wilson; X. Xu; S.J. Zweben; R. Akers; R.E. Barry; P. Beiersdorfer; J.M. Bialek; B. Blagojevic; P.T. Bonoli; M.D. Carter; W. Davis; B. Deng; L. Dudek; J. Egedal; R. Ellis; M. Finkenthal; J. Foley; E. Fredd; A. Glasser; T. Gibney; M. Gilmore; R.J. Goldston; R.E. Hatcher; R.J. Hawryluk; W. Houlberg; R. Harvey; S.C. Jardin; J.C. Hosea; H. Ji; M. Kalish; J. Lowrance; L.L. Lao; F.M. Levinton; N.C. Luhmann; R. Marsala; D. Mastravito; M.M. Menon; O. Mitarai; M. Nagata; G. Oliaro; R. Parsells; T. Peebles; B. Peneflor; D. Piglowski; G.D. Porter; A.K. Ram; M. Rensink; G. Rewoldt; P. Roney; K. Shaing; S. Shiraiwa; P. Sichta; D. Stotler; B.C. Stratton; R. Vero; W.R. Wampler; G.A. Wurden
Liquid Lithium Divertor and Scrape-Off-Layer Interactions on the National Spherical Torus Experiment: 2010 ? 2013 Progress Report
The implementation of the liquid Lithium Divertor (LLD) in NSTX presented a unique opportunity in plasma-material interactions studies. A high density Langmuir Probe (HDLP) array utilizing a dense pack of triple Langmuir probes was built at PPPL and the electronics designed and built by UIUC. It was shown that the HDLP array could be used to characterize the modification of the EEDF during lithium experiments on NSTX as well as characterize the transient particle loads during lithium experiments as a means to study ELMs. With NSTX being upgraded and a new divertor being installed, the HDLP array will not be used in NSTX-U. However UIUC is currently helping to develop two new systems for depositing lithium into NSTX-U, a Liquid Lithium Pellet Dripper (LLPD) for use with the granular injector for ELM mitigation and control studies as well as an Upward-Facing Lithium Evaporator (U-LITER) based on a flash evaporation system using an electron beam. Currently UIUC has Daniel Andruczyk Stationed at PPPL and is developing these systems as well as being involved in preparing the Materials Analysis Particle Probe (MAPP) for use in LTX and NSTX-U. To date the MAPP preparations have been completed. New sample holders were designed by UIUC?s Research Engineer at PPPL and manufactured at PPPL and installed. MAPP is currently being used on LTX to do calibration and initial studies. The LLPD has demonstrated that it can produce pellets. There is still some adjustments needed to control the frequency and particle size. Equipment for the U-LITER has arrived and initial test are being made of the electron beam and design of the U-LITER in progress. It is expected to have these ready for the first run campaign of NSTX-U.
L-H Threshold Studies in NSTX
Recent experiments in the low aspect ratio National Spherical Torus Experiment (NSTX) have been run in support of the high priority ITER and ITPA issue of access to the H-mode. Specifically, a series of experiments showed reduced power threshold values for deuterium vs helium plasmas, and for plasmas with lower current, lower triangularity and with lithium conditioning. Application of n=3 fields at the plasma edge resulted in higher power thresholds. To within the constraints of temporal and spatial resolutions, no systematic difference in T{sub e}, n{sub e}, p{sub e}, T{sub i}, v or their derivatives was found in discharges that transitioned into the H-mode versus those at slightly lower power that did not. Finally, H{sub 98y,2} {approx} 1 confinement quality could be achieved for powers just above the threshold power in ELM-free conditions.
Kaye, S M; Battaglia, D; Bell, R E; Chang, C S; Hosea, J; Kugel, H; LeBlanc, B P; Meyer, H; Park, G Y
Results from the RACE (Ring ACceleration Experiment) Compact Torus Acceleration Experiment
RACE (Ring ACceleration Experiment) is a proof-of-principle experiment aimed at demonstrating acceleration of magnetically confined compact torus plasma rings to directed kinetic energies well in excess of their magnetic and thermal energies. In the course of the first year of operation the following have been observed: successful formation of rings in the RACE geometry; acceleration of rings with large forces, F/sub accelerate/ approx.F/sub equilibrium/ without apparent degradation of the ring structure; peak velocities of approx. =2.5 x 10/sup 8/ cm/sec; acceleration efficiency of >30% at speeds of 1.5 x 10/sup 8/ cm/sec inferred from trajectory and capacitor bank data; kinetic to magnetic energy ratios approx.10 were observed. Experiments in the near future will be aimed at confirmation of the mass/energy measurements by calorimetry and direct density measurements.
Hammer, J.H.; Hartman, C.W.; Eddleman, J.L.; Kusse, B.
Integration of Microsoft Windows Applications with MDSplus Data Acquisition on the National Spherical Torus Experiment at the Princeton Plasma Physics Laboratory
Data acquisition on the National Spherical Torus Experiment (NSTX) at the Princeton Plasma Physics Laboratory (PPPL) has increasingly involved the use of Personal Computers (PC's) and specially developed ''turn-key'' hardware and software systems to control diagnostics. Interaction with these proprietary software packages is accomplished through use of Visual Basic, or Visual C++ and COM (Component Object Model) technology. COM is a software architecture that allows the components made by different software vendors to be combined into a variety of applications. This technology is particularly well suited to these systems because of its programming language independence, standards for function calling between components, and ability to transparently reference remote processes. COM objects make possible the creation of acquisition software that can control the experimental parameters of both the hardware and software. Synchronization of these applications for diagnostics, such as CCD camer as and residual gas analyzers, with the rest of the experiment event cycle at PPPL has been made possible by utilization of the MDSplus libraries for Windows. Instead of transferring large data files to remote disk space, Windows MDSplus events and I/O functions allow us to put raw data into MDSplus directly from IDL for Windows and Visual Basic. The combination of COM technology and the MDSplus libraries for Windows provide the tools for many new possibilities in versatile acquisition applications and future diagnostics.
Dana M. Mastrovito
Status and Plans for the National Spherical Torus Experimental Research Facility
An overview of the research capabilities and the future plans on the MA-class National Spherical Torus Experiment (NSTX) at Princeton is presented. NSTX research is exploring the scientific benefits of modifying the field line structure from that in more conventional aspect ratio devices, such as the tokamak. The relevant scientific issues pursued on NSTX include energy confinement, MHD stability at high beta, non-inductive sustainment, solenoid-free start-up, and power and particle handling. In support of the NSTX research goal, research tools are being developed by the NSTX team. In the context of the fusion energy development path being formulated in the US, an ST-based Component Test Facility (CTF) and, ultimately a high beta Demo device based on the ST, are being considered. For these, it is essential to develop high performance (high beta and high confinement), steady-state (non-inductively driven) ST operational scenarios and an efficient solenoid-free start-up concept. We will also briefly describe the Next-Step-ST (NSST) device being designed to address these issues in fusion-relevant plasma conditions.
M. Ono; M.G. Bell; R.E. Bell; J.M. Bialek; T. Bigelow; M. Bitter; plus 148 additional authors
Local scrape-off layer control using biased electrodes in NSTX
An experiment was designed to test the theory that biased electrodes can affect the local scrape-off layer (SOL) width by creating a strong radial ExB drift [Cohen, R.H. and Ryutov, D.D, Nucl. Fusion 37, 621 (1997)]. These electrodes were located near the outer midplane in the SOL of the National Spherical Torus Experiment (NSTX). The electrodes were biased at up to ?100 Volts, and the radial profile of the plasma between them was measured by an array of Langmuir probes. The biasing caused large changes in the local SOL profiles at least qualitatively consistent with this theory.
Zweben, S. J.; Maqueda, R. J.; Roquemore, A. L.; Bush, C. E.; Kaita, R.; Marsala, R. J.; Raitses, Y.; Cohen, R. H.; Ryutov, D. D.
NSTX Weekly Report (October 15, 2010) FY 2011 NSTX plasma operations started on October 4, 2010
of Density and Radiated Power Evolution Control using Magnetic ELM Pace-making in NSTX" by J.M. Canik (ORNL), "Prospects for pilot plants based on the tokamak, ST and stellarator" by J. Menard and "Lithium Technologies Experiment" by E. Fredrickson, "Recent Developments in High-Harmonic Fast Wave Physics in NSTX" by B.P. Le
Investigation of Ion Absorption of the High Harmonic Fast Wave in NSTX using HPRT
Understanding high harmonic fast wave (HHFW) power absorption by ions in a spherical torus (ST) is of critical importance to assessing the wave's viability as a means of heating and especially driving current. In this work, the HPRT code is used to calculate absorption for helium and deuterium, with and without minority hydrogen in National Spherical Torus Experiment (NSTX) plasmas using experimental EFIT code equilibria and kinetic profiles. HPRT is a two-dimensional ray-tracing code which uses the full hot plasma dielectric to compute the perpendicular wave number along the hot electron and cold ion plasma ray path. Ion and electron absorption dependence on antenna phasing, ion temperature, beta (subscript t), and minority temperature and concentration is analyzed. These results form the basis for comparisons with other codes, such as CURRAY, METS, TORIC, and AORSA.
Rosenberg, A.; Menard, J.E.; and LeBlanc, B.P.
Properties of Alfven Eigenmodes in the TAE range on the National Spherical Torus Experiment-Upgrade
A second Neutral Beam (NB) injection line is being installed on the NSTX Upgrade device, resulting in six NB sources with di erent tangency radii that will be available for heating and current drive. This work explores the properties of instabilities in the frequency range of the Toroidal Alfv#19;en Eigenmode (TAE) for NSTX-U scenarios with various NB injection geometries, from more perpendicular to more tangential, and with increased toroidal magnetic eld with respect to previous NSTX scenarios. Predictions are based on analysis through the ideal MHD code NOVA-K. For the scenarios considered in this work, modi cations of the Alfv#19;en continuum result in a frequency upshift and a broadening of the radial mode structure. The latter e ect may have consequences for fast ion transport and loss. Preliminary stability considerations indicate that TAEs are potentially unstable, with ion Landau damping representing the dominant damping mechanism
The Relationships Between ELM Suppression, Pedestal Profiles, and Lithium Wall Coatings in NSTX
Recently in the National Spherical Torus Experiment (NSTX), increasing lithium wall coatings suppressed edge localized modes (ELMs), gradually but not quite monotonically. This work details profile and stability analysis as ELMs disappeared throughout the lithium scan. While the quantity of lithium deposited between discharges did not uniquely determine the presence of ELMs, profile analysis demonstrated that lithium was correlated to wider density and pressure pedestals with peak gradients farther from the separatrix. Moreover, the ELMy and ELM-free discharges were cleanly separated by their density and pedestal widths and peak gradient locations. Ultimately, ELMs were only suppressed when lithium caused the density pedestal to widen and shift inward. These changes in the density gradient were directly reflected in the pressure gradient and calculated bootstrap current. This supports the theory that ELMs in NSTX are caused by peeling and/or ballooning modes, as kink/peeling modes are stabilized when the edge current and pressure gradient shift away from the separatrix. Edge stability analysis using ELITE corroborated this picture, as reconstructed equilibria from ELM-free discharges were generally farther from their kink/peeling stability boundaries than ELMy discharges. We conclude that density profile control provided by lithium is the key first step to ELM suppression in NSTX
D.P. Boyle, R. Maingi, P.B. Snyder, J. Manickam, T.H. Osborne, R.E. Bell, B.P. LeBlanc, and the NSTX Team
Impact of MHD Equilibrium Input Variations on the High-Beta Stability Boundaries of NSTX
Ideal MHD stability limits of anticipated plasma configurations for the National Spherical Torus Experiment (NSTX) [Ono, M., et al., Nucl. Fusion 40 (2000) 557] and the dependence on the parameters defining the MHD equilibrium are evaluated. The study provides a quantitative computational evaluation of the stability limit variations induced by changes to the equilibrium of NSTX high-beta plasmas. The analysis is based on a reference free-boundary equilibrium with beta = 41.5%, monotonic safety factor q profile, and broad pressure profile p. On this reference target local variation of the plasma boundary, safety factor q, and pressure p profiles are imposed. Localized inflection of the outboard plasma boundary, produced by near-field effects from poloidal shaping field coils, weaken the stability due to the destabilization of high-n ballooning modes. Variation of the q profile at different radial location can also degrade stability. Both experimental profiles from existing tokamaks and spherical torus machines and profiles generated from transport modeling of anticipated neutral-beam-heated plasmas are used. Degraded stability is found at increasing pressure peaking factor due to the destabilization of n = 1 kink/ballooning modes. Direct access to the second region of stability is found in certain configurations and, for the entire set of variations considered, the lower calculated beta-limits values are still in the range of 20.0% without considering the stabilizing effect of the passive conducting structures.
F. Paoletti; S.A. Sabbagh; J. Manickam; J. Menard; R.J. Akers; D. Gates; S.M. Kaye; L. Lao
H-Mode Turbulence, Power Threshold, ELM, and Pedestal Studies in NSTX
High-confinement mode (H-mode) operation plays a crucial role in NSTX [National Spherical Torus Experiment] research, allowing higher beta limits due to reduced plasma pressure peaking, and long-pulse operation due to high bootstrap current fraction. Here, new results are presented in the areas of edge localized modes (ELMs), H-mode pedestal physics, L-H turbulence, and power threshold studies. ELMs of several other types (as observed in conventional aspect ratio tokamaks) are often observed: (1) large, Type I ELMs, (2) ''medium'' Type II/III ELMs, and (3) giant ELMs which can reduce stored energy by up to 30% in certain conditions. In addition, many high-performance discharges in NSTX have tiny ELMs (newly termed Type V), which have some differences as compared with ELM types in the published literature. The H-mode pedestal typically contains between 25-33% of the total stored energy, and the NSTX pedestal energy agrees reasonably well with a recent international multi-machine scaling. We find that the L-H transition occurs on a {approx}100 {micro}sec timescale as viewed by a gas puff imaging diagnostic, and that intermittent quiescent periods precede the final transition. A power threshold identity experiment between NSTX and MAST shows comparable loss power at the L-H transition in balanced double-null discharges. Both machines require more power for the L-H transition as the balance is shifted toward lower single null. High field side gas fueling enables more reliable H-mode access, but does not always lead to a lower power threshold e.g., with a reduction of the duration of early heating. Finally the edge plasma parameters just before the L-H transition were compared with theories of the transition. It was found that while some theories can separate well-developed L- and H-mode data, they have little predictive value.
R. Maingi; C.E. Bush; E.D. Fredrickson; D.A. Gates; S.M. Kaye; B.P. LeBlanc; J.E. Menard; H. Meyer; D. Mueller; N. Nishino; A.L. Roquemore; S.A. Sabbagh; K. Tritz; S.J. Zweben; M.G. Bell; R.E. Bell; T. Biewer; J.A. Boedo; D.W. Johnson; R. Kaita; H.W. Kugel; R.J. Maqueda; T. Munsat; R. Raman; V.A. Soukhanovskii; T. Stevenson; D. Stutman
Characterization of the plasma current quench during disruptions in the National Spherical Torus Experiment
A detailed analysis of the plasma current quench in the National Spherical Torus Experiment [M.Ono, et al Nuclear Fusion 40, 557 (2000)] is presented. The fastest current quenches are fit better by a linear waveform than an exponential one. Area-normalized current quench times down to .4 msec/m2 have been observed, compared to the minimum of 1.7 msec/m2 recommendation based on conventional aspect ratio tokamaks; as noted in previous ITPA studies, the difference can be explained by the reduced self-inductance at low aspect ratio and high-elongation. The maximum instantaneous dIp/dt is often many times larger than the mean quench rate, and the plasma current before the disruption is often substantially less than the flat-top value. The poloidal field time-derivative during the disruption, which is directly responsible for driving eddy currents, has been recorded at various locations around the vessel. The Ip quench rate, plasma motion, and magnetic geometry all play important roles in determining the rate of poloidal field change.
Gerhardt, S.P., Menard, J.E., and the NSTX Research Team
Snowflake divertor configuration studies for NSTX-Upgrade
Snowflake divertor experiments in NSTX provide basis for PMI development toward NSTX-Upgrade. Snowflake configuration formation was followed by radiative detachment. Significant reduction of steady-state divertor heat flux observed in snowflake divertor. Impulsive heat loads due to Type I ELMs are partially mitigated in snowflake divertor. Magnetic control of snowflake divertor configuration is being developed. Plasma material interface development is critical for NSTX-U success. Four divertor coils should enable flexibility in boundary shaping and control in NSTX-U. Snowflake divertor experiments in NSTX provide good basis for PMI development in NSTX-Upgrade. FY 2009-2010 snowflake divertor experiments in NSTX: (1) Helped understand control of magnetic properties; (2) Core H-mode confinement unchanged; (3) Core and edge carbon concentration reduced; and (4) Divertor heat flux significantly reduced - (a) Steady-state reduction due to geometry and radiative detachment, (b) Encouraging results for transient heat flux handling, (c) Combined with impurity-seeded radiative divertor. Outlook for snowflake divertor in NSTX-Upgrade: (1) 2D fluid modeling of snowflake divertor properties scaling - (a) Edge and divertor transport, radiation, detachment threshold, (b) Compatibility with cryo-pump and lithium conditioning; (2) Magnetic control development; and (3) PFC development - PFC alignment and PFC material choice.
Soukhanovskii, V A
Investigation Of A Transient Energetic Charge Exchange Fux Enhancement (?spike-on-tail?) Observed In Neutral-beam-heated H-mode Discharges In The National Spherical Torus Experiment
In the National Spherical Torus Experiment (NSTX), a large increase in the charge exchange neutral flux localized at the Neutral Beam (NB) injection full energy is measured by the E||B (superimposed parallel electric and magnetic fields) Neutral Particle Analyzer (NPA). Termed the High-Energy Feature (HEF), it appears on the NB-injected energetic ion spectrum only in discharges where tearing or kink-type modes (f < 50 kHz) are absent, Toroidal Alfv�n Eigenmode (TAE) activity (f ~ 50 - 150 kHz) is weak and Global Alfv�n Eigenmode (GAE) activity (f ~ 400 � 1000 kHz) is robust. Compressional Alfv�n eigenmode (CAE) activity (f > 1000 kHz) is usually sporadic or absent during the HEF event. The HEF exhibits growth times of ?t ~ 20 - 80 ms, durations of ~ 100 � 600 ms and peak-to-base flux ratios up to H = Fmax /Fmin ~ 10. In infrequent cases, a slowing down distribution below the HEF energy can develop that continues to evolve over periods > 100 ms, a time scale long compared with the typical fast ion equilibration times. HEFs are Transient energetic charge exchange flux enhancement (?spike-on-tail?) 2 observed only in H-mode (not L-mode) discharges with injected power Pb ? 4 MW and in the pitch range ? = vll /v ~ 0.7 � 0.9; i.e. only for passing particles. Increases of ~ 10 - 30 % in the measured neutron yield and total stored energy that are observed to coincide with the feature appear to be driven by concomitant broadening of measured Te(r), Ti(r) and ne(r) profiles and not the HEF itself. While the HEF has minimal impact on plasma performance, it nevertheless poses a challenging wave-particle interaction phenomenon to understand. Candidate mechanisms for HEF formation are developed based on quasilinear theory of wave-particle interaction. The only mechanism found to lead to the large NPA flux ratios, H = Fmax /Fmin , observed in NSTX is the quasilinear evolution of the energetic ion distribution, Fb(E,?,r), in phase space and the concomitant loss of some particles, which occurs due to the cyclotron interaction of the particles with destabilized modes having sufficiently high frequencies, F ~ 700 - 1000 kHz, in the plasma frame that are tentatively identified as Global Alfv�n Eigenmodes.
S.S. Medley et. al.
High Harmonic Fast Wave Heating Efficiency Enhancement and Current Drive at Longer Wavelength on the National Spherical Torus Experiment
High harmonic fast wave heating and current drive CD are being developed on the National Spherical Torus Experiment M. Ono et al., Nucl. Fusion 41, 1435 2001 for supporting startup and sustainment of the spherical torus plasma. Considerable enhancement of the core heating efficiency from 44% to 65% has been obtained for CD phasing of the antenna strap-to-strap = 90 , k= 8 m 1 by increasing the magnetic field from 4.5 to 5.5 kG. This increase in efficiency is strongly correlated to moving the location of the onset density for perpendicular fast wave propagation nonsetBk 2 / away from the antenna face and wall, and hence reducing the propagating surface wave fields. Radio frequency RF waves propagating close to the wall at lower B and k can enhance power losses from both the parametric decay instability PDI and wave dissipation in sheaths and structures around the machine. The improved efficiency found here is attributed to a reduction in the latter, as PDI losses are little changed at the higher magnetic field. Under these conditions of higher coupling efficiency, initial measurements of localized CD effects have been made and compared with advanced RF code simulations.
Hosea, J. [Princeton Plasma Physics Laboratory (PPPL); Bell, R. E. [Princeton Plasma Physics Laboratory (PPPL); LeBlanc, B [Princeton Plasma Physics Laboratory (PPPL); Phillips, Cynthia [Princeton Plasma Physics Laboratory (PPPL); Taylor, G. [Princeton Plasma Physics Laboratory (PPPL); Valeo, Dr Ernest [Princeton Plasma Physics Laboratory (PPPL); Wilson, J. R. [Princeton Plasma Physics Laboratory (PPPL); Jaeger, Erwin Frederick [ORNL; Ryan, Philip Michael [ORNL; Wilgen, John B [ORNL; Yuh, H. [Nova Photonics; Levinton, F. [Fusion Physics and Technology; Sabbagh, S. A. [Columbia University; Tritz, K. [Johns Hopkins University; Parker, J. [Cornell University; Bonoli, P. [Massachusetts Institute of Technology (MIT); Harvey, R. W. [CompX, Del Mar, CA
H-mode fueling optimization with the supersonic deuterium jet in NSTX
High-performance, long-pulse 0.7-1.2 MA 6-7 MW NBI-heated small-ELM H-mode plasma discharges are developed in the National Spherical Torus Experiment (NSTX) as prototypes for confinement and current drive extrapolations to future spherical tori. It is envisioned that innovative lithium coating techniques for H-mode density pumping and a supersonic deuterium jet for plasma refueling will be used to achieve the low pedestal collisionality and low n{sub e}/n{sub G} fractions (0.3-0.6), both of which being essential conditions for maximizing the non-inductive (bootstrap and beam driven) current fractions. The low field side supersonic gas injector (SGI) on NSTX consists of a small converging-diverging graphite Laval nozzle and a piezoelectric gas valve. The nozzle is capable of producing a deuterium jet with Mach number M {le} 4, estimated gas density at the nozzle exit n {le} 5 x 10{sup 23} m{sup -3}, estimated temperature T {ge} 70 K, and flow velocity v = 2:4 km/s. The nozzle Reynolds number Reis {approx_equal} 6000. The nozzle and the valve are enclosed in a protective carbon fiber composite shroud and mounted on a movable probe at a midplane port location. Despite the beneficial L-mode fueling experience with supersonic jets in limiter tokamaks, there is a limited experience with fueling of high-performance H-mode divertor discharges and the associated density, MHD stability, and MARFE limits. In initial supersonic deuterium jet fueling experiments in NSTX, a reliable H-mode access, a low NBI power threshold, P{sub LH} {le} 2 MW, and a high fueling efficiency (0.1-0.4) have been demonstrated. Progress has also been made toward a better control of the injected fueling gas by decreasing the uncontrolled high field side (HFS) injector fueling rate by up to 95 % and complementing it with the supersonic jet fueling. These results motivated recent upgrades to the SGI gas delivery and control systems. The new SGI-Upgrade (SGI-U) capabilities include multi-pulse ms-scale controls and a reservoir gas pressure up to P{sub 0} = 5000 Torr. In this paper we summarize recent progress toward optimization of H-mode fueling in NSTX using the SGI-U.
Soukhanovskii, V A; Bell, M G; Bell, R E; Gates, D A; Kaita, R; Kugel, H W; LeBlanc, B P; Lundberg, D P; Maingi, R; Menard, J E; Raman, R; Roquemore, A L; Stotler, D P
Varying the Pre-discharge Lithium Wall Coatings to Alter the Characteristics of the ELM-free H-mode Pedestal in NSTX
A previous experiment in the National Spherical Torus Experiment (NSTX) showed pre-discharge lithium deposition gradually suppresed edge-localized modes (ELMs) and had nearly continuous relationships with reduced recycling and transport. In this paper, additional data filled gaps in the earlier experiment, and demonstrates that recycling, confinement, and pedestal structure continued to improve with additional lithium, even after ELMs were completely suppressed. New analysis shows that toroidal rotation and ion temperature also increased continuously with additional lithium. Besides its evolution with additional lithium, we also characterize the time evolution of the ELM-free H-mode pedestal as average density rose and impurities accumulated. We find that the pedestal structure, divertor heat flux and Dalpha profiles, and inferred recycling coefficient did not change significantly, at least until radiative losses become dominant. This suggests that the low-recycling properties of lithium were not significantly degraded over the duration of the discharge.
D.P. Boyle, J.M. Canik, R. Maing, P.B. Snyder, T.H. Osborne, and the NSTX Team
Final Scientific/Technical Report, USDOE Award DE-FG-02ER54684, Recipient: CompX, Project Title: Fokker-Planck/Ray Tracing for Electron Bernstein and Fast Wave Modeling in Support of NSTX.
This DOE grant supported fusion energy research, a potential long-term solution to the world's energy needs. Magnetic fusion, exemplified by confinement of very hot ionized gases, i.e., plasmas, in donut-shaped tokamak vessels is a leading approach for this energy source. Thus far, a mixture of hydrogen isotopes has produced 10's of megawatts of fusion power for seconds in a tokamak reactor at Princeton Plasma Physics Laboratory in New Jersey. The research grant under consideration, ER54684, uses computer models to aid in understanding and projecting efficacy of heating and current drive sources in the National Spherical Torus Experiment, a tokamak variant, at PPPL. The NSTX experiment explores the physics of very tight aspect ratio, almost spherical tokamaks, aiming at producing steady-state fusion plasmas. The current drive is an integral part of the steady-state concept, maintaining the magnetic geometry in the steady-state tokamak. CompX further developed and applied models for radiofrequency (rf) heating and current drive for applications to NSTX. These models build on a 30 year development of rf ray tracing (the all-frequencies GENRAY code) and higher dimensional Fokker-Planck rf-collisional modeling (the 3D collisional-quasilinear CQL3D code) at CompX. Two mainline current-drive rf modes are proposed for injection into NSTX: (1) electron Bernstein wave (EBW), and (2) high harmonic fast wave (HHFW) modes. Both these current drive systems provide a means for the rf to access the especially high density plasma--termed high beta plasma--compared to the strength of the required magnetic fields. The CompX studies entailed detailed modeling of the EBW to calculate the efficiency of the current drive system, and to determine its range of flexibility for driving current at spatial locations in the plasma cross-section. The ray tracing showed penetration into NSTX bulk plasma, relatively efficient current drive, but a limited ability to produce current over the whole radial plasma cross-section. The actual EBW experiment will cost several million dollars, and remains in the proposal stage. The HHFW current drive system has been experimentally implemented on NSTX, and successfully drives substantial current. The understanding of the experiment is to be accomplished in terms of general concepts of rf current drive, and also detailed modeling of the experiment which can discern the various competing processes which necessarily occur simultaneously in the experiment. An early discovery of the CompX codes, GENRAY and CQL3D, was that there could be significant interference between the neutral beam injection fast ions in the machine (injected for plasma heating) and the HHFW energy. Under many NSTX experimental conditions, power which could go to the fast ions would then be unavailable for current drive by the desired HHFW interaction with electrons. This result has been born out by experiments; the modeling helps in understanding difficulties with HHFW current drive, and has enabled adjustment of the experiment to avoid interaction with neutral beam injected fast ions thereby achieving stronger HHFW current drive. The detailed physics modeling of the various competing processes is almost always required in fusion energy plasma physics, to ensure a reasonably accurate and certain interpretation of the experiment, enabling the confident design of future, more advanced experiments and ultimately a commercial fusion reactor. More recent work entails detailed investigation of the interaction of the HHFW radiation for fast ions, accounting for the particularly large radius orbits in NSTX, and correlations between multiple HHFW-ion interactions. The spherical aspect of the NSTX experiment emphasized particular physics such as the large orbits which are present to some degree in all tokamaks, but gives clearer clues on the resulting physics phenomena since competing physics effects are reduced.
R.W. Harvey, CompX, Del Mar, CA 92014
Parametric Decay during HHFW on NSTX
High Harmonic Fast Wave (HHFW) heating experiments on NSTX have been observed to be accompanied by significant edge ion heating (T{sub i} >> T{sub e}). This heating is found to be anisotropic with T{sub perp} > T{sub par}. Simultaneously, coherent oscillations have been detected with an edge Langmuir probe. The oscillations are consistent with parametric decay of the incident fast wave ({omega} > 13{omega}{sub ci}) into ion Bernstein waves and an unobserved ion-cyclotron quasi-mode. The observation of anisotropic heating is consistent with Bernstein wave damping, and the Bernstein waves should completely damp in the plasma periphery as they propagate toward a cyclotron harmonic resonance. The number of daughter waves is found to increase with rf power, and to increase as the incident wave's toroidal wavelength increases. The frequencies of the daughter wave are separated by the edge ion cyclotron frequency. Theoretical calculations of the threshold for this decay in uniform plasma indicate an extremely small value of incident power should be required to drive the instability. While such decays are commonly observed at lower harmonics in conventional ICRF heating scenarios, they usually do not involve the loss of significant wave power from the pump wave. On NSTX an estimate of the power loss can be found by calculating the minimum power required to support the edge ion heating (presumed to come from the decay Bernstein wave). This calculation indicates at least 20-30% of the incident rf power ends up as decay waves.
J.R. Wilson; S. Bernabei; T. Biewer; S. Diem; J. Hosea; B. LeBlanc; C.K. Phillips; P. Ryan; D.W. Swain
NSTX Plasma Response to Lithium Coated Divertor
NSTX experiments have explored lithium evaporated on a graphite divertor and other plasma facing components in both L- and H- mode confinement regimes heated by high-power neutral beams. Improvements in plasma performance have followed these lithium depositions, including a reduction and eventual elimination of the HeGDC time between discharges, reduced edge neutral density, reduced plasma density, particularly in the edge and the SOL, increased pedestal electron and ion temperature, improved energy confinement and the suppression of ELMs in the H-mode. However, with improvements in confinement and suppression of ELMs, there was a significant secular increase in the effective ion charge Zeff and the radiated power in H-mode plasmas as a result of increases in the carbon and medium-Z metallic impurities. Lithium itself remained at a very low level in the plasma core, <0.1%. Initial results are reported from operation with a Liquid Lithium Divertor (LLD) recently installed.
H.W. Kugel, M.G. Bell, J.P. Allain, R.E. Bell, S. Ding, S.P. Gerhardt, M.A. Jaworski, R. Kaita, J. Kallman, S.M. Kaye, B.P. LeBlanc, R. Maingi, R. Majeski, R. Maqueda, D.K. Mansfield, D. Mueller, R. Nygren, S.F. Paul, R. Raman, A.L. Roquemore, S.A. Sabbagh, H. Schneider, C.H. Skinner, V.A. Soukhanovskii, C.N. Taylor, J.R. Timberlak, W.R. Wampler, L.E. Zakharov, S.J. Zweben, and the NSTX Research Team
NSTX experiments have explored lithium evaporated on a graphite divertor and other plasma facing components in both L- and H- mode confinement regimes heated by high-power neutral beams. Improvements in plasma performance have followed these lithium depositions, including a reduction and eventual elimination of the HeGDC time between discharges, reduced edge neutral density, reduced plasma density, particularly in the edge and the SOL, increased pedestal electron and ion temperature, improved energy confinement and the suppression of ELMs in the H-mode. However, with improvements in confinement and suppression of ELMs, there was a significant secular increase in the effective ion charge Zeff and the radiated power in H-mode plasmas as a result of increases in the carbon and medium-Z metallic impurities. Lithium itself remained at a very low level in the plasma core, Lithium Divertor (LLD) recently installed.
NSTX Computing and Controls Paul Sichta
Areas 250 databases, 10,000 records 400 MEDM displays 15 Sequencer Programs 600 PV's to Channel Spring 2010 #12;The Good ... Control systems supports the research - over 95% reliability for NSTX machine. EPICS : reliable and low maintenance MDSplus : generally good. NSTX experienced problems
Lithium Wall Conditioning And Surface Dust Detection On NSTX
Lithium evaporation onto NSTX plasma facing components (PFC) has resulted in improved energy confinement, and reductions in the number and amplitude of edge-localized modes (ELMs) up to the point of complete ELM suppression. The associated PFC surface chemistry has been investigated with a novel plasma material interface probe connected to an in-vacuo surface analysis station. Analysis has demonstrated that binding of D atoms to the polycrystalline graphite material of the PFCs is fundamentally changed by lithium - in particular deuterium atoms become weakly bonded near lithium atoms themselves bound to either oxygen or the carbon from the underlying material. Surface dust inside NSTX has been detected in real-time using a highly sensitive electrostatic dust detector. In a separate experiment, electrostatic removal of dust via three concentric spiral-shaped electrodes covered by a dielectric and driven by a high voltage 3-phase waveform was evaluated for potential application to fusion reactors
Skinner, C H; Bell, M G; Friesen, F.Q.L.; Heim, B; Jaworski, M A; Kugel, H; Maingi, R; Rais, B
The Dependence of H-mode Energy Confinement and Transport on Collisionality in NSTX
Understanding the dependence of confi nement on collisionality in tokamaks is important for the design of next-step devices, which will operate at collisionalities at least one order of magnitude lower than in present generation. A wide range of collisionality has been obtained in the National Spherical Torus Experiment (NSTX) by employing two different wall conditioning techniques, one with boronization and between-shot helium glow discharge conditioning (HeGDC+B), and one using lithium evaporation (Li EVAP). Previous studies of HeGDC+B plasmas indicated a strong and favorable dependence of normalized con nement on collisionality. Discharges with lithium conditioning discussed in the present study gen- erally achieved lower collisionality, extending the accessible range of collisionality by almost an order of unity. While the confinement dependences on dimensional, engineering variables of the HeGDC+B and Li EVAP datasets differed, collisionality was found to unify the trends, with the lower collisionality lithium conditioned discharges extending the trend of increasing normalized confi nement time with decreasing collisionality when other dimension less variables were held as fi xed as possible. This increase of confi nement with decreasing collisionality was driven by a large reduction in electron transport in the outer region of the plasma. This result is consistent with gyrokinetic calculations that show microtearing and Electron Temperature Gradient modes to be more stable for the lower collisionality discharges. Ion transport, near neoclassical at high collisionality, became more anomalous at lower collisionality, possibly due to the growth of hybrid TEM/KBM modes in the outer regions of the plasma
S.M.. Kaye, S. Gerhardt, W. Guttenfelder, R. Maingi, R.E. Bell, A. Diallo, B.P. LeBlanc and M. Podesta
Understanding the dependence of confi nement on collisionality in tokamaks is important for the design of next-step devices, which will operate at collisionalities at least one order of magnitude lower than in present generation. A wide range of collisionality has been obtained in the National Spherical Torus Experiment (NSTX) by employing two different wall conditioning techniques, one with boronization and between-shot helium glow discharge conditioning (HeGDC+B), and one using lithium evaporation (Li EVAP). Previous studies of HeGDC+B plasmas indicated a strong and favorable dependence of normalized con nement on collisionality. Discharges with lithium conditioning discussed in the present study gen- erally achieved lower collisionality, extending the accessible range of collisionality by almost an order of unity. While the confinement dependences on dimensional, engineering variables of the HeGDC+B and Li EVAP datasets differed, collisionality was found to unify the trends, with the lower collisionality lithium conditioned discharges extending the trend of increasing normalized confi nement time with decreasing collisionality when other dimension less variables were held as fi xed as possible. This increase of confi nement with decreasing collisionality was driven by a large reduction in electron transport in the outer region of the plasma. This result is consistent with gyrokinetic calculations that show microtearing and Electron Temperature Gradient modes to be more stable for the lower collisionality discharges. Ion transport, near neoclassical at high collisionality, became more anomalous at lower collisionality, possibly due to the growth of hybrid TEM/KBM modes in the outer regions of the plasma.
Simulation of Diffusive Lithium Evaporation Onto the NSTX Vessel Walls
A model for simulating the diffusive evaporation of lithium into a helium filled NSTX vacuum vessel is described and validated against an initial set of deposition experiments. The DEGAS 2 based model consists of a three-dimensional representation of the vacuum vessel, the elastic scattering process, and a kinetic description of the evaporated atoms. Additional assumptions are required to account for deuterium out-gassing during the validation experiments. The model agrees with the data over a range of pressures to within the estimated uncertainties. Suggestions are made for more discriminating experiments that will lead to an improved model.
D.P. Stotler, C.H. Skinner, W.R. Blanchard, P.S. Krstic, H.W. Kugel, H. Schneider, and L.E. Zakharov
Spherical torus fusion reactor
DOE Patents (OSTI)
The object of this invention is to provide a compact torus fusion reactor with dramatic simplification of plasma confinement design. Another object of this invention is to provide a compact torus fusion reactor with low magnetic field and small aspect ratio stable plasma confinement. In accordance with the principles of this invention there is provided a compact toroidal-type plasma confinement fusion reactor in which only the indispensable components inboard of a tokamak type of plasma confinement region, mainly a current conducting medium which carries electrical current for producing a toroidal magnet confinement field about the toroidal plasma region, are retained.
Martin Peng, Y.K.M.
Gas-Puff-Imaging (GPI) is a two dimensional diagnostic which measures the edge D? light emission from a neutral D2 gas puff nears the outer mid-plane of NSTX. DEGAS 2 is a 3-D Monte Carlo code used to model neutral transport and atomic physics in tokamak plasmas. In this paper we compare measurements of the D? light emission obtained by GPI on NSTX with DEGAS 2 simulations of D? light emission for specific experiments. Both the simulated spatial distribution and absolute intensity of the D? light emission agree well with the experimental data obtained between ELMs in H-mode. __________________________________________________
B. Cao, D.P. Stotler, S.J. Zweben, M. Bell, A. Diallo and B. Leblanc
Gas-Puff-Imaging (GPI) is a two dimensional diagnostic which measures the edge D? light emission from a neutral D2 gas puff nears the outer mid-plane of NSTX. DEGAS 2 is a 3-D Monte Carlo code used to model neutral transport and atomic physics in tokamak plasmas. In this paper we compare measurements of the D? light emission obtained by GPI on NSTX with DEGAS 2 simulations of D? light emission for specific experiments. Both the simulated spatial distribution and absolute intensity of the D? light emission agree well with the experimental data obtained between ELMs in H-mode.
NSTX Liquid Lithium Divertor (LLD) Design Status and Plans
NSTX Liquid Lithium Divertor (LLD) Design Status and Plans Office of Science H. W. Kugel, PPPL Design Status and Plans (Kugel) 2July 28, 2008 Motivation for NSTX Lithium Research · NSTX research with solid lithium is aimed initially towards using liquid lithium to control density, edge collisionality
Recent Progress in the NSTX/NSTX-U Lithium Program and Prospects for Reactor-Relevant Liquid-Lithium Based Divertor Development
Developing a reactor compatible divertor has been identified as a particularly challenging technology problem for magnetic confinement fusion. While tungsten has been identified as the most attractive solid divertor material, the NSTX/NSTX-U lithium (Li) program is investigating the viability of liquid lithium (LL) as a potential reactor compatible divertor plasma facing component (PFC) . In the near term, operation in NSTX-U is projected to provide reactor-like divertor heat loads < 40 MW/m^2 for 5 s. During the most recent NSTX campaign, ~ 0.85 kg of Li was evaporated onto the NSTX PFCs where a ~50% reduction in heat load on the Liquid Lithium Divertor (LLD) was observed, attributable to enhanced divertor bolometric radiation. This reduced divertor heat flux through radiation observed in the NSTX LLD experiment is consistent with the results from other lithium experiments and calculations. These results motivate an LL-based closed radiative divertor concept proposed here for NSTX-U and fusion reactors. With an LL coating, the Li is evaporated from the divertor strike point surface due to the intense heat. The evaporated Li is readily ionized by the plasma due to its low ionization energies, and the ionized Li ions can radiate strongly, resulting in a significant reduction in the divertor heat flux. Due to the rapid plasma transport in divertor plasma, the radiation values can be significantly enhanced up to ~ 11 MJ/cc of LL. This radiative process has the desired function of spreading the focused divertor heat load to the entire divertor chamber facilitating the divertor heat removal. The LL divertor surface can also provide a "sacrificial" surface to protect the substrate solid material from transient high heat flux such as the ones caused by the ELMs. The closed radiative LLD concept has the advantages of providing some degree of partition in terms of plasma disruption forces on the LL, Li particle divertor retention, and strong divertor pumping action from the Li-coated divertor chamber wall. By operating at a lower temperature than the first wall, the LLD can serve to purify the entire reactor chamber, as impurities generally migrate toward lower temperature Li-condensed surfaces. To maintain the LL purity, a closed LL loop system with a modest capacity (e.g., ~ 1 Liter/sec for ~ 1% level "impurities") is envisioned for a steady-state 1 GW-electric class fusion power plant.
M. Ono, et al.
A fusion reactor is provided having a near spherical-shaped plasma with a modest central opening through which straight segments of toroidal field coils extend that carry electrical current for generating a toroidal magnet plasma confinement fields. By retaining only the indispensable components inboard of the plasma torus, principally the cooled toroidal field conductors and in some cases a vacuum containment vessel wall, the fusion reactor features an exceptionally small aspect ratio (typically about 1.5), a naturally elongated plasma cross section without extensive field shaping, requires low strength magnetic containment fields, small size and high beta. These features combine to produce a spherical torus plasma in a unique physics regime which permits compact fusion at low field and modest cost.
Peng, Yueng-Kay M. (Oak Ridge, TN)
Progress on advanced tokamak and steady-state scenario development on DIII-D and NSTX
Advanced tokamak (AT) research seeks to develop steady-state operating scenarios for ITER and other future devices from a demonstrated scientific basis. Normalized target parameters for steady-state operation on ITER are 100% non-inductive current operation with a bootstrap current fraction f(BS) >= 60%, q(95) similar to 4-5 and G = beta H-N(scaling)/q(95)(2) >= 0.3. Progress in realizing such plasmas is considered in terms of the development of plasma control capabilities and scientific understanding, leading to improved AT performance. NSTX has demonstrated active resistive wall mode stabilization with low, ITER-relevant, rotation rates below the critical value required for passive stabilization. On DIII-D, experimental observations and GYRO simulations indicate that ion internal transport barrier (ITB) formation at rational-q surfaces is due to equilibrium zonal flows generating high local E x B shear levels. In addition, stability modelling for DIII-D indicates a path to operation at beta N >= 4 with q(min) >= 2, using broad, hollow current profiles to increase the ideal wall stability limit. Both NSTX and DIII-D have optimized plasma performance and expanded AT operational limits. NSTX now has long-pulse, high performance discharges meeting the normalized targets for an spherical torus-based component test facility. DIII-D has developed sustained discharges combining high beta and ITBs, with performance approaching levels required for AT reactor concepts, e. g. beta(N) = 4, H-89 = 2.5, with f(BS) > 60%. Most importantly, DIII-D has developed ITER steady-state demonstration discharges, simultaneously meeting the targets for steady-state Q >= 5 operation on ITER set out above, substantially increasing confidence in ITER meeting its steady-state performance objective.
Doyle, E. J. [University of California, Los Angeles; Peng, Yueng Kay Martin [ORNL
NSTX Upgrade Armor Plate Backing Plate
NSTX Upgrade Armor Plate Backing Plate NSTXU-CALC-24-02-00 Rev 0 February 17, 2011 Prepared By # NSTXU_CALC-24-02-00 Revision # 00 WP #: 1508 (ENG-032) Purpose of Calculation: 1.) To qualify the Armor backing plate calculation 2.) Build and evaluate a Finite Element Model for The Armor Eddy Current
NSTX Report on FES Joint Facilities Research Milestone 2010
Annual Target: Conduct experiments on major fusion facilities to improve understanding of the heat transport in the tokamak scrape-off layer (SOL) plasma, strengthening the basis for projecting divertor conditions in ITER. The divertor heat flux profiles and plasma characteristics in the tokamak scrape-off layer will be measured in multiple devices to investigate the underlying thermal transport processes. The unique characteristics of C-Mod, DIII-D, and NSTX will enable collection of data over a broad range of SOL and divertor parameters (e.g., collisionality ?*, beta ?, parallel heat flux q||, and divertor geometry). Coordinated experiments using common analysis methods will generate a data set that will be compared with theory and simulation.
R. Maingi, J-W. Ahn, T.K. Gray, A.G. McLean, V.A. Soukhanovskii
Improvement in Plasma Performance with Lithium Coatings in NSTX
Lithium as a plasma-facing material has attractive features, including a reduction in the recycling of hydrogenic species and the potential for withstanding high heat and neutron fluxes in fusion reactors. Dramatic effects on plasma performance with lithium-coated plasma-facing components (PFC's) have been demonstrated on many fusion devices, including TFTR, T-11M, and FT-U. Using a liquid-lithium-filled tray as a limiter, the CDX-U device achieved very significant enhancement in the confinement time of ohmically heated plasmas. The recent NSTX experiments reported here have demonstrated, for the first time, significant and recurring benefits of lithium PFC coatings on divertor plasma performance in both L- and H- mode regimes heated by neutral beams.
Kaita, R
Lithium as a plasma-facing material has attractive features, including a reduction in the recycling of hydrogenic species and the potential for withstanding high heat and neutron fluxes in fusion reactors. Dramatic effects on plasma performance with lithium-coated plasma-facing components (PFCOs) have been demonstrated on many fusion devices, including TFTR, [1] T-11M, [2] and FT-U. [3] Using a liquid-lithium-filled tray as a limiter, the CDX-U device achieved very significant enhancement in the confinement time of ohmically heated plasmas. [4] The recent NSTX experiments reported here have demonstrated, for the first time, significant and recurring benefits of lithium PFC coatings on divertor plasma performance in both L- and H- mode regimes heated by neutral beams.
Kaita, R; Ahn, J -W; Allain, J P; Bell, M G; Bell, R; Boedo, J; Bush, C; Mansfield, D; Menard, J; Mueller, D; Ono, M; Paul, S; Raman, R; Roquemore, A L; Ross, P W; Sabbagh, S; Schneider, H; Skinner, C H; Soukhanovskii, V; Stevenson, T; Stotler, D; Timberlake, J; Wampler, W R; Wilgen, J B
Ring Bolted Joint NSTX-CALC-132-11
NSTX Ring Bolted Joint NSTX-CALC-132-11 Rev 0 March 2011 Prepared By assemblies which are connected through a stepped lap joint with four stainless steel bolts. These bolts, must provide sufficient compressive force, through combined preload, to resist the joint separation for all
Developing a reactor compatible divertor has been identified as a particularly challenging technology problem for magnetic confinement fusion. While tungsten has been identified as the most attractive solid divertor material, the NSTX/NSTX-U lithium (Li) program is investigating the viability of liquid lithium (LL) as a potential reactor compatible divertor plasma facing component (PFC) . In the near term, operation in NSTX-U is projected to provide reactor-like divertor heat loads heat load on the Liquid Lithium Divertor (LLD) was observed, attributable to enhanced divertor bolometric radiation. This reduced divertor heat flux through radiation observed in the NSTX LLD experiment is consistent with the results from other lithium experiments and calculations. These results motivate an LL-based closed radiative divertor concept proposed here for NSTX-U and fusion reactors. With an LL coating, the Li is evaporated from the divertor strike point surface due to the intense heat. The evaporated Li is readily ionized by the plasma due to its low ionization energies, and the ionized Li ions can radiate strongly, resulting in a significant reduction in the divertor heat flux. Due to the rapid plasma transport in divertor plasma, the radiation values can be significantly enhanced up to ~ 11 MJ/cc of LL. This radiative process has the desired function of spreading the focused divertor heat load to the entire divertor chamber facilitating the divertor heat removal. The LL divertor surface can also provide a "sacrificial" surface to protect the substrate solid material from transient high heat flux such as the ones caused by the ELMs. The closed radiative LLD concept has the advantages of providing some degree of partition in terms of plasma disruption forces on the LL, Li particle divertor retention, and strong divertor pumping action from the Li-coated divertor chamber wall. By operating at a lower temperature than the first wall, the LLD can serve to purify the entire reactor chamber, as impurities generally migrate toward lower temperature Li-condensed surfaces. To maintain the LL purity, a closed LL loop system with a modest capacity (e.g., ~ 1 Liter/sec for ~ 1% level "impurities") is envisioned for a steady-state 1 GW-electric class fusion power plant.
A fusion pilot plant study was initiated to clarify the development needs in moving from ITER to a first of a kind fusion power plant. The mission of the pilot plant was set to encompass component test and fusion nuclear science missions yet produce net electricity with high availability in a device designed to be prototypical of the commercial device. The objective of the study was to evaluate three different magnetic configuration options, the advanced tokamak (AT), spherical tokamak (ST) and compact stellarator (CS) in an effort to establish component characteristics, maintenance features and the general arrangement of each candidate device. With the move to look beyond ITER the fusion community is now beginning to embark on DEMO reactor studies with an emphasis on defining configuration arrangements that can meet a high availability goal. This paper reviews the AT pilot plant design, detailing the selected maintenance approach, the device arrangement and sizing of the in-vessel components. Details of interfacing auxiliary systems and services that impact the ability to achieve high availability operations will also be discussed.
Brown, T; Goldston, R J; El-Guebaly, L; Kessel, C; Neilson, G H; Malang, S; Menard, J E; Prager, S; Scott, S; Titus, P; Waganer, L
NSTX Weekly Report (May 21, 2010) FY 2010 NSTX plasma operations
Plasma Physics and Plasma Material Interactions in the Fusion Power Plant Regime" 20-21 May 2010 at UC comments during the session on "Experimental benchmarking of models for power plants." Jon Menard chaired National University), "Study of RF Driven Plasma Waves using FIReTIP on NSTX" by J. Kim (Pohang Institute
Progress in Simulating Turbulent Electron Thermal Transport in NSTX
Nonlinear simulations based on multiple NSTX discharge scenarios have progressed to help differentiate unique instability mechanisms and to validate with experimental turbulence and transport data. First nonlinear gyrokinetic simulations of microtearing (MT) turbulence in a high-beta NSTX H-mode discharge predict experimental levels of electron thermal transport that are dominated by magnetic flutter and increase with collisionality, roughly consistent with energy confinement times in dimensionless collisionality scaling experiments. Electron temperature gradient (ETG) simulations predict significant electron thermal transport in some low and high beta discharges when ion scales are suppressed by E x B shear. Although the predicted transport in H-modes is insensitive to variation in collisionality (inconsistent with confinement scaling), it is sensitive to variations in other parameters, particularly density gradient stabilization. In reversed shear (RS) Lmode discharges that exhibit electron internal transport barriers, ETG transport has also been shown to be suppressed nonlinearly by strong negative magnetic shear, s<<0. In many high beta plasmas, instabilities which exhibit a stiff beta dependence characteristic of kinetic ballooning modes (KBM) are sometimes found in the core region. However, they do not have a distinct finite beta threshold, instead transitioning gradually to a trapped electron mode (TEM) as beta is reduced to zero. Nonlinear simulations of this "hybrid" TEM/KBM predict significant transport in all channels, with substantial contributions from compressional magnetic perturbations. As multiple instabilities are often unstable simultaneously in the same plasma discharge, even on the same flux surface, unique parametric dependencies are discussed which may be useful for distinguishing the different mechanisms experimentally.
Guttenfelder, Walter
Solenoid-free Plasma Start-up in NSTX using Transient CHI
Experiments in NSTX have now demonstrated the coupling of toroidal plasmas produced by the technique of Coaxial Helicity Injection (CHI) to inductive sustainment and ramp-up of the toroidal plasma current. In these discharges, the central Ohmic transformer was used to apply an inductive loop voltage to discharges with a toroidal current of about 100 kA created by CHI. The coupled discharges have ramped up to >700 kA and transitioned into an H-mode demonstrating compatibility of this startup method with conventional operation. The electron temperature in the coupled discharges reached over 800 eV and the resulting plasma had low inductance, which is preferred for long-pulse high performance discharges. These results from NSTX in combination with the previously obtained record 160 kA non-inductively-generated startup currents in an ST or tokamak in NSTX demonstrate that CHI is a viable solenoid-free plasma startup method for future STs and tokamaks.
Raman, R; Jarboe, T; Nelson, B; Mueller, D; Soukhanovskii, V A
Edge Turbulence Velocity Changes with Lithium Coating on NSTX
Lithium coating improves energy confinement and eliminates edge localized modes in NSTX, but the mechanism of this improvement is not yet well understood. We used the gas-puff-imaging (GPI) diagnostic on NSTX to measure the changes in edge turbulence which occurred during a scan with variable lithium wall coating, in order to help understand the reason for the confinement improvement with lithium. There was a small increase in the edge turbulence poloidal velocity and a decrease in the poloidal velocity fluctuation level with increased lithium. The possible effect of varying edge neutral density on turbulence damping was evaluated for these cases in NSTX. __________________________________________________
A. Cao, S.J. Zweben, D.P. Stotler, M. Bell, A. Diallo, S.M. Kaye and B. LeBlanc
/or MIL-HDBK- 5). If a small database exists for a candidate material considered for a design component
Dynamics of the Disruption Halo Current Toroidal Asymmetry in NSTX
This paper describes the dynamics of disruption halo current non-axisymmetries in the lower divertor of the National Spherical Torus Experiment [M. Ono, et al. Nuclear Fusion 40, 557 (2000)]. While. The halo currents typically have a strongly asymmetric structure where they enter the divertor floor, and this asymmetry has been observed to complete up to 7 toroidal revolutions over the duration of the halo current pulse. However, the rotation speed and toroidal extend of the asymmetry can vary significantly during the pulse. The rotation speed, halo current pulse duration, and total number of revolutions tend to be smaller in cases with large halo currents. The halo current pattern is observed to become toroidally symmetric at the end of the halo current pulse. It is proposed that this symmeterization is due to the loss of most or all of the closed field line geometry in the final phase of the vertical displacement event.
S.P. Gerhardt
Time Resolved Deposition Measurements in NSTX
Time-resolved measurements of deposition in current tokamaks are crucial to gain a predictive understanding of deposition with a view to mitigating tritium retention and deposition on diagnostic mirrors expected in next-step devices. Two quartz crystal microbalances have been installed on NSTX at a location 0.77m outside the last closed flux surface. This configuration mimics a typical diagnostic window or mirror. The deposits were analyzed ex-situ and found to be dominantly carbon, oxygen, and deuterium. A rear facing quartz crystal recorded deposition of lower sticking probability molecules at 10% of the rate of the front facing one. Time resolved measurements over a 4-week period with 497 discharges, recorded 29.2 {micro}g/cm{sup 2} of deposition, however surprisingly, 15.9 {micro}g/cm{sup 2} of material loss occurred at 7 discharges. The net deposited mass of 13.3 {micro}g/cm{sup 2} matched the mass of 13.5 {micro}g/cm{sup 2} measured independently by ion beam analysis. Monte Carlo modeling suggests that transient processes are likely to dominate the deposition.
C.H. Skinner; H. Kugel; A.L. Roquemore; J. Hogan; W.R. Wampler; the NSTX team
Evaporated lithium surface coatings in NSTX.
Two lithium evaporators were used to evaporate more than 100 g of lithium on to the NSTX lower divertor region. Prior to each discharge, the evaporators were withdrawn behind shutters, where they also remained during the subsequent HeGDC applied for periods up to 9.5 min. After the HeGDC, the shutters were opened and the LITERs were reinserted to deposit lithium on the lower divertor target for 10 min, at rates of 10-70 mg/min, prior to the next discharge. The major improvements in plasma performance from these lithium depositions include: (1) plasma density reduction as a result of lithium deposition; (2) suppression of ELMs; (3) improvement of energy confinement in a low-triangularity shape; (4) improvement in plasma performance for standard, high-triangularity discharges; (5) reduction of the required HeGDC time between discharges; (6) increased pedestal electron and ion temperature; (7) reduced SOL plasma density; and (8) reduced edge neutral density.
Zakharov, L. (Princeton Plasma Physics Laboratory, Princeton, NJ); Gates, D. (Princeton Plasma Physics Laboratory, Princeton, NJ); Menard, J. (Princeton Plasma Physics Laboratory, Princeton, NJ); Maingi, R. (Oak Ridge National Laboratory, Oak Ridge, TN); Schneider, H. (Princeton Plasma Physics Laboratory, Princeton, NJ); Mueller, D. (Princeton Plasma Physics Laboratory, Princeton, NJ); Wampler, William R.; Roquemore, A. L. (Princeton Plasma Physics Laboratory, Princeton, NJ); Kallman, Jeffrey K. (Princeton Plasma Physics Laboratory, Princeton, NJ); Sabbagh, S. (Columbia University, New York, NY); LeBlanc, B. (Princeton Plasma Physics Laboratory, Princeton, NJ); Raman, R. (University of Washington, Seattle, WA); Ono, M. (Princeton Plasma Physics Laboratory, Princeton, NJ); Wilgren, J. (Oak Ridge National Laboratory, Oak Ridge, TN); Allain, J.P. (Purdue University, West Lafayette, IN); Timberlake, J. (Princeton Plasma Physics Laboratory, Princeton, NJ); Stevenson, T. (Princeton Plasma Physics Laboratory, Princeton, NJ); Ross, P. W. (Princeton Plasma Physics Laboratory, Princeton, NJ); Majeski, R. (Princeton Plasma Physics Laboratory, Princeton, NJ); Kugel, Henry W. (Princeton Plasma Physics Laboratory, Princeton, NJ); Skinner, C. H. (Princeton Plasma Physics Laboratory, Princeton, NJ); Gerhardt, S. (Princeton Plasma Physics Laboratory, Princeton, NJ); Paul, S. (Princeton Plasma Physics Laboratory, Princeton, NJ); Bell, R. (Princeton Plasma Physics Laboratory, Princeton, NJ); Kaye, S. M. (Princeton Plasma Physics Laboratory, Princeton, NJ); Kaita, R. (Princeton Plasma Physics Laboratory, Princeton, NJ); Soukhanovskii, V. (Lawrence Livermore National Laboratory, Livermore, CA); Bell, Michael G. (Princeton Plasma Physics Laboratory, Princeton, NJ); Mansfield, D. (Princeton Plasma Physics Laboratory, Princeton, NJ)
Energy Science and Technology Software Center (OSTI)
002440MLTPL00 3D Torus Routing Engine Module for OFA OpenSM v. 1.0� http://www.openfabrics.org/git?p=sashak/management.git;a=sum�
Implications of NSTX Lithium Results for Magnetic Fusion Research
Lithium wall coating techniques have been experimentally explored on NSTX for the last five years. The lithium experimentation on NSTX started with a few milligrams of lithium injected into the plasma as pellets and it has evolved to a lithium evaporation system which can evaporate up to ~ 100 g of lithium onto the lower divertor plates between lithium reloadings. The unique feature of the lithium research program on NSTX is that it can investigate the effects of lithium in H-mode divertor plasmas. This lithium evaporation system thus far has produced many intriguing and potentially important results; the latest of these are summarized in a companion paper by H. Kugel. In this paper, we suggest possible implications and applications of the NSTX lithium results on the magnetic fusion research which include electron and global energy confinement improvements, MHD stability enhancement at high beta, ELM control, H-mode power threshold reduction, improvements in radio frequency heating and non-inductive plasma start-up performance, innovative divertor solutions and improved operational efficiency.
M. Ono, M.G. Bell, R.E. Bell, R. Kaita, H.W. Kugel, B.P. LeBlanc, J.M. Canik, S. Diem, S.P.. Gerhardt, J. Hosea, S. Kaye, D. Mansfield, R. Maingi, J. Menard, S. F. Paul, R. Raman, S.A. Sabbagh, C.H. Skinner, V. Soukhanovskii, G. Taylor, and the NSTX Research Team
Recent Improvements in Fast Wave Heating in NSTX
Recent improvements in high-harmonic fast wave (HHFW) core heating in NSTX are attributed to using lithium conditioning, and other wall conditioning techniques, to move the onset density for perpendicular fast wave propagation further from the antenna. This has resulted in the first observation of HHFW core electron heating in deuterium plasma at a launched toroidal wavenumber, k? = -3 m-1, NSTX record core electron temperatures of 5 keV in helium and deuterium discharges and, for the first time, significant HHFW core electron heating of deuterium neutral-beam-fuelled H-mode plasmas. Also, k? = -8 m-1 heating of the plasma startup and plasma current ramp-up has resulted in significant core electron heating, even at central electron densities as low as ~ 4x1018 m-3.
G. Taylor, R.E. Bell, R.W. Harvey, J.C. Hosea, E.F. Jaeger, B.P. LeBlanc, C.K. Phillips, P.M. Ryan, E.J. Valeo, J.B. Wilgen, J.R. Wilson, and the NSTX Team
Upward-facing Lithium Flash Evaporator for NSTX-U
NSTX plasma performance has been significantly enhanced by lithium conditioning [1]. To date, the lower divertor and passive plates have been conditioned by downward facing lithium evaporators (LITER) as appropriate for lower null plasmas. The higher power operation expected from NSTX-U requires double null plasma operation in order to distribute the heat flux between the upper and lower divertors making it desirable to coat the upper divertor region with Li as well. An upward aiming LITER (U-LITER) is presently under development and will be inserted into NSTX-U using a horizontal probe drive located in a 6" upper midplane port. In the retracted position the evaporator will be loaded with up to 300 mg of Li granules utilizing one of the calibrated NSTX Li powder droppers[2]. The evaporator will then be inserted into the vessel in a location within the shadow of the RF limiters and will remain in the vessel during the discharge. About 10 seconds before a discharge, it will be rapidly heated and the lithium completely evaporated onto the upper divertor, thus avoiding the complication of a shutter that prevents evaporation during the shot when the diagnostic shutters are open. The minimal time interval between the evaporation and the start of the discharge will avoid the passivation of the lithium by residual gases and enable the study of the conditioning effects of un-passivated Li surfaces [3]. Two methods are being investigated to accomplish the rapid (few second) heating of the lithium. A resistive method relies on passing a large current through a Li filled crucible. A second method requires using a 3 kW e-beam gun to heat the Li. In this paper the evaporator systems will be described and the pros and cons of each heating method will be discussed.
Roquemore, A. L.
Plasma Facing Surface Composition During NSTX Li Experiments
Lithium conditioned plasma facing surfaces have lowered recycling and enhanced plasma performance on many fusion devices. However, the nature of the plasma-lithium surface interaction has been obscured by the difficulty of in-tokamak surface analysis. We report laboratory studies of the chemical composition of lithium surfaces exposed to typical residual gases found in tokamaks. Solid lithium and a molybdenum alloy (TZM) coated with lithium has been examined using x-ray photoelectron spectroscopy, temperature programmed desorption, and Auger electron spectroscopy both in ultrahigh vacuum conditions and after exposure to trace gases. Lithium surfaces near room temperature were oxidized after exposure to 1-2 Langmuirs of oxygen or water vapor. The oxidation rate by carbon monoxide was four times less. Lithiated PFC surfaces in tokamaks will be oxidized in about 100 s depending on the tokamak vacuum conditions.
C.H. Skinner, R. Sullenberger, B.E. Koel, M.A. Jaworski and H.W. Kugel
Lithium Coatings on NSTX Plasma Facing Components and Its Effects On Boundary Control, Core Plasma Performance, and Operation
NSTX high-power divertor plasma experiments have used in succession lithium pellet injection (LPI), evaporated lithium, and injected lithium powder to apply lithium coatings to graphite plasma facing components. In 2005, following wall conditioning and LPI, discharges exhibited edge density reduction and performance improvements. Since 2006, first one, and now two lithium evaporators have been used routinely to evaporate lithium onto the lower divertor region at total rates of 10-70 mg/min for periods 5-10 min between discharges. Prior to each discharge, the evaporators are withdrawn behind shutters. Significant improvements in the performance of NBI heated divertor discharges resulting from these lithium depositions were observed. These evaporators are now used for more than 80% of NSTX discharges. Initial work with injecting fine lithium powder into the edge of NBI heated deuterium discharges yielded comparable changes in performance. Several operational issues encountered with lithium wall conditions, and the special procedures needed for vessel entry are discussed. The next step in this work is installation of a Liquid Lithium Divertor surface on the outer part of the lower divertor.
H.W.Kugel, M.G.Bell, H.Schneider, J.P.Allain, R.E.Bell, R Kaita, J.Kallman, S. Kaye, B.P. LeBlanc, D. Mansfield, R.E. Nygen, R. Maingi, J. Menard, D. Mueller, M. Ono, S. Paul, S.Gerhardt, R.Raman, S.Sabbagh, C.H.Skinner, V.Soukhanovskii, J.Timberlake, L.E.Zakharov, and the NSTX Research Team
Easy Web Interfaces to IDL Code for NSTX Data Analysis
Reusing code is a well-known Software Engineering practice to substantially increase the efficiency of code production, as well as to reduce errors and debugging time. A variety of "Web Tools" for the analysis and display of raw and analyzed physics data are in use on NSTX [1], and new ones can be produced quickly from existing IDL [2] code. A Web Tool with only a few inputs, and which calls an IDL routine written in the proper style, can be created in less than an hour; more typical Web Tools with dozens of inputs, and the need for some adaptation of existing IDL code, can be working in a day or so. Efficiency is also increased for users of Web Tools because o f the familiar interface of the web browser, and not needing X-windows, accounts, passwords, etc. Web Tools were adapted for use by PPPL physicists accessing EAST data stored in MDSplus with only a few man-weeks of effort; adapting to additional sites should now be even easier. An overview of Web Tools in use on NSTX, and a list of the most useful features, is also presented.
W.M. Davis
Effect of Lithium PFC Coatings on NSTX Density Control
Lithium coatings on the graphite plasma facing components (PFCs) in NSTX are being investigated as a tool for density profile control and reducing the recycling of hydrogen isotopes. Repeated lithium pellet injection into Center Stack Limited and Lower Single Null Ohmic Helium Discharges were used to coat graphite surfaces that had been pre-conditioned with Ohmic Helium Discharges of the same shape to reduce their contribution to hydrogen isotope recycling. The following deuterium NBI reference discharges exhibited a reduction in density by a factor of about 3 for limited and 2 for diverted plasmas respectively, and peaked density profiles. Recently, a lithium evaporator has been used to apply thin coatings on conditioned and unconditioned PFCs. Effects on the plasma density and the impurities were obtained by pre-conditioning the PFCs with ohmic helium discharges, and performing the first deuterium NBI discharge as soon as possible after applying the lithium coating.
Kugel, H W; Bell, M G; Bush, C; Gates, D; Gray, T; Kaita, R; Leblanc, B; Maingi, R; Majeski, R; Mansfield, D; Mueller, D; Raman, R; Roquemore, A L; Sabbagh, S; Skinner, C H; Soukhanovskii, V; Stevenson, T; Zakharov, L
Magnetic surfaces in an axisymmetric torus
A method is developed for specifying the boundary equilibrium magnetic surface in an axially symmetric torus by using the absolute values of the magnetic field B = B{sub s}({theta}) and the gradient of the poloidal flux vertical bar vertical bar {nabla}{Psi} vertical bar = vertical bar {nabla}{Psi} vertical bar {sub s}({theta}) in a special flux coordinate system. By setting two surface constants (e.g., the safety factor q and dp/d{Psi}) and matching the absolute values of the magnetic field and the flux gradient on a closed magnetic surface, it is possible to find all equilibrium magnetic functions (including n {center_dot} {nabla} ln B and the local shear s) and all constants (including the toroidal current J and the shear d{mu}/d{Psi}) on this surface. Such a non-traditional formulation of the boundary conditions in solving the stability problem in an axisymmetric torus allows one to impose intentional conditions on plasma confinement and MHD stability at the periphery of the system.
Skovoroda, A. A., E-mail: email@example.com [National Research Centre Kurchatov Institute (Russian Federation)
High-beta tokamak research Torus I and Torus II. Quarterly status report, 1 April-30 June 1978
Status of the high-beta tokamak research program at Columbia University is reported for the period 1 April through 30 June 1978. Activities on Torus I Belt Pinch and Torus II high beta tokamak are discussed. Engineering improvements, budget, schedule personnel and capital equipment considerations are also presented.
Gross, R.A.
Observation of EHO in NSTX and Theoretical Study of its Active Control Using HHFW Antenna
Two important topics in the tokamak ELM control, using the non-axisymmetric (3D) magnetic perturbations, are studied in NSTX and combined envisioning ELM control in the future NSTX-U operation: Experimental observations of the edge harmonic oscillation in NSTX (not necessarily the same as EHOs in DIII-D), and theoretical study of its external drive using the high harmonic fast wave (HHFW) antenna as a 3D field coil. Edge harmonic oscillations were observed particularly well in NSTX ELM-free operation with low n core modes, with various diagnostics confirming n = 4 ~#24; 6 edge-localized and coherent oscillations in 2 ~#24; 8kHz frequency range. These oscillations seem to have a favored operational window in rotational shear, similarly to EHOs in DIII-D QH modes . However, in NSTX, they are not observed to provide particle or impurity control, possibly due to their weak amplitudes, of a few mm displacements, as measured by reflectometry. The external drive of these modes has been proposed in NSTX, by utilizing audio-frequency currents in the HHFW antenna straps. Analysis shows that the HHFW straps can be optimized to maximize n = 4 ~#24; 6 while minimizing n = 1 ~#24; 3. Also, IPEC calculations show that the optimized configuration with only 1kAt current can produce comparable or larger displacements than the observed internal modes. If this optimized external drive can be constructively combined, or further resonated with the internal modes, the edge harmonic oscillations in NSTX may be able to produce sufficient particle control to modify ELMs.
J.-K. Park, et. al.
NEUTRAL BEAM ARMOR FOR NSTX UPGRADE K. Tresemer, T. Stevenson, C. Priniski, J. Winkelman, L. Bryant, R. Wood
NEUTRAL BEAM ARMOR FOR NSTX UPGRADE K. Tresemer, T. Stevenson, C. Priniski, J. Winkelman, L. Bryant in these upgrades are the relocation and upgrade of the NSTX Neutral Beam Armor to capture both sets of beamline the space required to accomplish this, it has been proposed to relocate and reuse the existing armor array
RF heating and current drive on NSTX with high
NSTX is a small aspect ratio tokamak (R = 0.85 m, a = 0.65 m). The High Harmonic Fast Wave (HHFW) system is a 30 MHz, 12-element array capable of launching both symmetric and directional wave spectra for plasma heating and non-inductive current drive. It has delivered up to 6 MW for short pulses and has routinely operated at ~3 MW for 100-400 ms pulses. Results include strong, centrally-peaked electron heating in both D and He plasmas for both high and low phase velocity spectra. H-modes were obtained with application of HHFW power alone, with stored energy doubling after the L-H transition. Beta poloidal as large as unity has been obtained with significant fractions (0.4) of bootstrap current. Differences in the loop voltage are observed depending on whether the array is phased to drive current in the co- or counter-current directions. A fast ion tail with energies extending up to 140 keV has been observed when HHFW interacts with 80 keV neutral beams; neutron rate and lost ion measurements, as well as modeling, indicate significant power absorption by the fast ions. Radial rf power deposition and driven current profiles have been calculated with ray tracing and kinetic full-wave codes and compared with measurements.
Ryan, Philip Michael [ORNL; Peng, Yueng Kay Martin [ORNL
Mechanical Design of the NSTX Liquid Lithium Divertor
The Liquid Lithium Divertor (LLD) on NSTX will be the first test of a fully-toroidal liquid lithium divertor in a high-power magnetic confinement device. It will replace part of the lower outboard divertor between a specified inside and outside radius, and ultimately provide a lithium surface exposed to the plasma with enough depth to absorb a significant particle flux. There are numerous technical challenges involved in the design. The lithium layer must be as thin as possible, and maintained at a temperature between 200 and 400 degrees Celsius to minimize lithium evaporation. This requirement leads to the use of a thick copper substrate, with a thin stainless steel layer bonded to the plasma-facing surface. A porous molybdenum layer is then plasma-sprayed onto the stainless steel, to provide a coating that facilitates full wetting of the surface by the liquid lithium. Other challenges include the design of a robust, vacuumcompatible heating and cooling system for the LLD. Replacement graphite tiles that provided the proper interface between the existing outer divertor and the LLD also had to be designed, as well as accommodation for special LLD diagnostics. This paper describes the mechanical design of the LLD, and presents analyses showing the performance limits of the LLD.
R. Ellis, R. Kaita, H. Kugel, G. Paluzzi, M. Viola and R. Nygren
Initial Results from the Lost Alpha Diagnostics on Joint European Torus
Two devices have been installed in the Joint European Torus (JET) vacuum vessel near the plasma boundary to investigate the loss of energetic ions and fusion products in general and alpha particles in particular during the upcoming JET experiments. These devices are (i) a set of multichannel thin foil Faraday collectors, and (ii) a well collimated scintillator which is optically connected to a charge-coupled device. Initial results, including the radial energy and poloidal dependence of lost ions from hydrogen and deuterium plasmas during the 2005�06 JET restart campaign, will be presented.
Darrow, Doug; Cecil, Ed; Ellis, Bob; Fullard, Keith; Hill, Ken; Horton, Alan; Kiptily, Vasily; Pedrick, Les; Reich, Matthias
Maass Cusp Forms on Singly Punctured Two-Torus
Quantum mechanical systems on punctured surfaces modeled by hyperbolic spaces can play an interesting role in exploring quantum chaos and in studying behaviour of future quantum nano-devices. The case of singly-punctured two-torus, for example, has been well-studied in the literature particularly for its scattering states. However, the bound states on the punctured torus given by Maass cusp forms are lesser known. In this note, we report on the algorithm of numerically computing these functions and we present ten lower-lying eigenvalues for each odd and even Maass cusp forms.
Siddig, Abubaker Ahmed Mohamed [Laboratory of Computational Sciences and Informatics, Institute for Mathematical Research Universiti Putra Malaysia, 43400 UPM Serdang, Selangor (Malaysia); Shah, Nurisya Mohd [Theoretical Physics Group, Department of Physics, Faculty of Science Universiti Putra Malaysia, 43400 UPM Serdang, Selangor (Malaysia); Zainuddin, Hishamuddin [Laboratory of Computational Sciences and Informatics, Institute for Mathematical Research Universiti Putra Malaysia, 43400 UPM Serdang, Selangor (Malaysia); Theoretical Physics Group, Department of Physics, Faculty of Science Universiti Putra Malaysia, 43400 UPM Serdang, Selangor (Malaysia)
From Large N Matrices to the Noncommutative Torus
We describe how and to what extent the noncommutative two-torus can be approximated by a tower of finite-dimensional matrix geometries. The approximation is carried out for both irrational and rational deformation parameters by embedding the algebra of the noncommutative torus into an approximately finite algebra. The construction is a rigorous derivation of the recent discretizations of noncommutative gauge theories using finite dimensional matrix models, and it shows precisely how the continuum limits of these models must be taken. We clarify various aspects of Morita equivalence using this formalism and describe some applications to noncommutative Yang-Mills theory.
G. Landi; F. Lizzi; R. J. Szabo
Predicting HHFW Heating Efficiency on NSTX via Whole-Device Full-Wave Simulation
We present a qualitative comparison of NSTX HHFW heating efficiency observations with results from the AORSA whole-device, linear simulation. The simulation retains a realistic geometry and core plasma kinetic physics such that scrape-off plasma linear RF fields can be calculated. By examining L-mode and neutral beam heated H-mode scenarios we quantify the conditions that result in a fast-wave coaxial mode in the scrape-off plasma. These large amplitude coaxial modes are expected to damp on collisions or couple to non-linear damping mechanisms and be correlated to an observed drop in core heating efficiency.
Green, D. L.; Berry, L. A.; Ryan, P. M. [Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, Tennessee 37831-6169 (United States); Jaeger, E. F. [XCEL Engineering Inc., 1066 Commerce Park Dr., Oak Ridge, TN 37830 (United States)
Disruption Analysis and Response Implicattions of Passive Plates for the NSTX Upgrade
The NSTX upgrade project requires analysis qualifications of existing vacuum vessel and passive stabilizing plates for increased plasma performance. Vertical stability is critically dependent on the passive conducting structure that surrounds the plasma. In this paper, the passive conducting structure is analyzed for the upgrade condition during plasma disruption to ensure the level of stress in the stabilizing plates and the fastener is within its design limits. The counter-bore of the passive plates for bolting is evaluated in details and counter-bore bushing is redesigned to prevent shear failure during disruptions as a result of high pulling and pushing forces, particularly for support at the corner bolts
Yuhu Zhai, Peter Titus, Art Brooks, and Ron Hatcher
White Paper for Developing Electromagnetic Particle Injector system for ITER on NSTX-U University of Washington (19 July 2012)
White Paper for Developing Electromagnetic Particle Injector system for ITER on NSTX-U University of Washington (19 July 2012) 1/2 White email@example.com This white paper describes our plans for developing a new system for safely
A parallel implementation of Strassen's matrix multiplication algorithm for wormhole-routed all-port 2D torus networks
A new parallel implementation of Strassen's matrix multiplication algorithm is proposed for massively parallel supercomputers with 2D, all-port torus interconnection networks. The proposed algorithm employs a special conflict-free routing pattern for ... Keywords: 2D torus, Fast Matrix Multiplication, Parallel processing, Strassen's matrix multiplication, Torus interconnection networks
Cesur Baransel; Kayhan M. ?mre
Fabrication of the 320-CM-OD all-ceramic ZT-40 torus
The fabrication of the ZT-40 torus, a large complex all-ceramic toroidal plasma containment vessel, is described. Several glass sealants covering the temperature range of 500 to 1300/sup 0/C, were developed and used to ''braze'' segments of the torus together, sapphire windows to the torus and the required pump-out and diagnostic parts to the ceramic vacuum vessel. Designs of window seals were developed that allowed sealing of the sapphire windows in a vertical position with minimum sealing glass flow.
Hauth, W.E.; Blake, R.D.; Rutz, H.L.; Dickinson, J.M.
BayesCLUMPY: BAYESIAN INFERENCE WITH CLUMPY DUSTY TORUS MODELS
Our aim is to present a fast and general Bayesian inference framework based on the synergy between machine learning techniques and standard sampling methods and apply it to infer the physical properties of clumpy dusty torus using infrared photometric high spatial resolution observations of active galactic nuclei. We make use of the Metropolis-Hastings Markov Chain Monte Carlo algorithm for sampling the posterior distribution function. Such distribution results from combining all a priori knowledge about the parameters of the model and the information introduced by the observations. The main difficulty resides in the fact that the model used to explain the observations is computationally demanding and the sampling is very time consuming. For this reason, we apply a set of artificial neural networks that are used to approximate and interpolate a database of models. As a consequence, models not present in the original database can be computed ensuring continuity. We focus on the application of this solution scheme to the recently developed public database of clumpy dusty torus models. The machine learning scheme used in this paper allows us to generate any model from the database using only a factor of 10{sup -4} of the original size of the database and a factor of 10{sup -3} in computing time. The posterior distribution obtained for each model parameter allows us to investigate how the observations constrain the parameters and which ones remain partially or completely undetermined, providing statistically relevant confidence intervals. As an example, the application to the nuclear region of Centaurus A shows that the optical depth of the clouds, the total number of clouds, and the radial extent of the cloud distribution zone are well constrained using only six filters. The code is freely available from the authors.
Asensio Ramos, A.; Ramos Almeida, C. [Instituto de AstrofIsica de Canarias, 38205, La Laguna, Tenerife (Spain)], E-mail: firstname.lastname@example.com
Mechanical design considerations of a spherical torus volumetric neutron source
The mechanical design of a spherical torus based volumetric neutron source (ST VNS) is being studied under the support of a DOE-SBIR funding. A device capable of staged operation from a neutron wall loading of 0.5-5.0 MW/m(2) has been scoped out, as the physics and engineering design assumptions are raised from modest to aggressive levels. Margins in the design are ensured since operation of the VNS will be adequate st a wall loading of 2 MW/m(2). The device has a naturally diverted plasma with major radius of 1.07 m, a minor radius of 0.77 m for an aspect ratio of 1.4, an elongation of 3 and triangularity of 0,6. In the neutral beam driven version, the plasma current is 11.1 MA and the toroidal field at the plasma major radius is 2.13 T, The baseline fusion power is 151 MW giving an average neutron wall loading of 2 MV/m(2) on the outboard side over an accessible area of over 15 m(2) for blanket testing. The device utilizes a normal Cu conducting bell jar as the return leg of the toroidal field current, a concept developed at the Oak Ridge National Laboratory. The current is carried by an unshielded single-turn center post (CP) made of dispersion strengthened Cu which is cooled by water in a single pass from top to bottom. A special sliding electrical interface between the CP and the bell jar is provided on the upper end to allow for differential expansion and to isolate the CP from tensile and torsional forces from the bell jar. The ohmic heating in the CP is 153 MW at the start of operation and increases to 178 MW after 3 full power years of operation. Over this period the maximum Cu temperature does not exceed 160 C. This report primarily deals with the design of the CP, one of the most challenging Issues of a low aspect ratio spherical torus. Maintenance approaches for the Or and the divertor assemblies have been determined and are addressed in the paper.
Sviatoslavky, I. N. [University of Wisconsin, Madison; Peng, Yueng Kay Martin [ORNL
Current Projects | U.S. DOE Office of Science (SC)
Office of Science (SC) Website
Current Current Projects Princeton Site Office (PSO) PSO Home About Current Projects Contract Management Environment, Safety and Health (ES&H) Contact Information Princeton Site Office U.S. Department of Energy P.O. Box 102 Princeton, NJ 08543 P: (609) 243-3700 F: (609) 243-2032 Current Projects Print Text Size: A A A RSS Feeds FeedbackShare Page National Spherical Torus Experiment (NSTX) The National Spherical Torus Experiment (NSTX) at the U.S. Department of Energy's Princeton Plasma Physics Laboratory (PPPL) is yielding research results that may open an attractive path towards developing fusion energy as an abundant, safe, affordable and environmentally sound means of generating electricity. The NSTX device is exploring a novel structure for the magnetic field used to contain the hot ionized gas, called
Transition to ELM-free improved H-mode by lithium deposition on NSTX graphite divertor surfaces
Lithium evaporated onto plasma facing components in the NSTX lower divertor has made dramatic improvements in discharge performance. As lithium accumulated, plasmas previously exhibiting robust Type 1 ELMs gradually transformed into discharges with intermittent ELMs and finally into continuously evolving ELM-free discharges. During this sequence, other discharge parameters changed in a complicated manner. As the ELMs disappeared, energy confinement improved and remarkable changes in edge and scrape-off layer plasma properties were observed. These results demonstrate that active modification of plasma surface interactions can preempt large ELMs.
Mansfield, D K; Kugel, H W; Maingi, R; Bell, M G; Bell, R; Kaita, R; Kallman, J; Kaye, S; LeBlanc, B; Mueller, D; Paul, S; Raman, R; Roquemore, A L; Sabbagh, S; Schneider, H; Skinner, C H; Soukhanovskii, V A; Timberlake, J; Wilgen, J; Zakharov, L
Transition to ELM-free Improved H-mode by Lithium Deposition on NSTX Graphite Divertor Surfaces
Mansfield, D. K.; Kugel, H. W.; Maingi, R.; Bell, M. G.; Bell, R.; Kaita, R.; Kallman, J.; Kaye, S.; LeBlanc, B.; Mueller, D.; Paul, S.; Raman, R.; Roquemore, L.; Sabbagh, S.; Schneider, H.; Skinner, C. H.; Soukhanovskii, V.; Timberlake, J.; J. Wilgen,,; Zakharov, L.
Comparison of Measurement And Modeling Of Current Profile Changes Due To Neutral Bean Ion Redistribution During TAE Avalanches in NSTX
Brief "avalanches" of toroidal Alfven eigenmodes (TAEs) are observed in NSTX plasmas with several different n numbers simultaneously present. These affect the neutral beam ion distribution as evidenced by a concurrent drop in the neutron rate and, sometimes, beam ion loss. Guiding center orbit modeling has shown that the modes can transiently render portions of the beam ion phase space stochastic. The resulting redistribution of beam ions can also create a broader beam-driven current profile and produce other changes in the beam ion distribution function
Darrow, Douglas
Experiences Experiences with 100Gbps Network Applications Mehmet Balman, Eric Pouyoul, Yushu Yao, E. Wes Bethel Burlen Loring, Prabhat, John Shalf, Alex Sim, and Brian L. Tierney Lawrence Berkeley National Laboratory One Cyclotron Road Berkeley, CA, 94720, USA {mbalman,epouyoul,yyao,ewbethel,bloring,prabhat,jshalf,asim,firstname.lastname@example.com ABSTRACT 100Gbps networking has finally arrived, and many research and educational institutions have begun to deploy 100Gbps routers and services. ESnet and Internet2 worked together to make 100Gbps networks available to researchers at the Supercomputing 2011 con- ference in Seattle Washington. In this paper, we describe two of the first applications to take advantage of this network. We demon- strate a visualization application that enables remotely located sci- entists to gain insights from large datasets. We also demonstrate climate
White Paper for Massive Gas Injection studies in NSTX-U in support of ITER research University of Washington (19 July 2012)
White Paper for Massive Gas Injection studies in NSTX-U in support of ITER research University of Washington (19 July 2012) 1/2 White email@example.com , firstname.lastname@example.com , firstname.lastname@example.com, firstname.lastname@example.com This white paper describes
The deformations of flat affine structures on the two-torus
The group action which defines the moduli problem for the deformation space of flat affine structures on the two-torus is the action of the affine group $\\Aff(2)$ on $\\bbR^2$. Since this action has non-compact stabiliser $\\GL(2,\\bbR)$, the underlying locally homogeneous geometry is highly non-Riemannian. In this article, we describe the deformation space of all flat affine structures on the two-torus. In this context interesting phenomena arise in the topology of the deformation space, which, for example, is \\emph{not} a Hausdorff space. This contrasts with the case of constant curvature metrics, or conformal structures on surfaces, which are encountered in classical Teichm\\"uller theory. As our main result on the space of deformations of flat affine structures on the two-torus we prove that the holonomy map from the deformation space to the variety of conjugacy classes of homomorphisms from the fundamental group of the two-torus to the affine group is a local homeomorphism.
Baues, Oliver
Equivalence of Two Approaches to Yang-Mills on Non-commutative Torus
There are two notions of Yang-Mills action functional in noncommutative geometry. We show that for noncommutative n-torus both these notions agree. We also prove a structure theorem on the Hermitian structure of a finitely generated projective modules over spectrally invariant subalgebras of $C^*$-algebras.
Partha Sarathi Chakraborty; Satyajit Guin
Phases of a two-dimensional large-N gauge theory on a torus
We consider two-dimensional large N gauge theory with D adjoint scalars on a torus, which is obtained from a D+2-dimensional pure Yang-Mills theory on T{sup D+2} with D small radii. The two-dimensional model has various phases characterized by the holonomy of the gauge field around noncontractible cycles of the 2-torus. We determine the phase boundaries and derive the order of the phase transitions using a method developed in an earlier work (hep-th/0910.4526), which is nonperturbative in the 't Hooft coupling and uses a 1/D expansion. We embed our phase diagram in the more extensive phase structure of the D+2-dimensional Yang-Mills theory and match with the picture of a cascade of phase transitions found earlier in lattice calculations. We also propose a dual gravity system based on a Scherk-Schwarz compactification of a D2 brane wrapped on a 3-torus and find a phase structure which is similar to the phase diagram found in the gauge theory calculation.
Mandal, Gautam [Department of Theoretical Physics, Tata Institute of Fundamental Research, Mumbai 400 005 (India); Morita, Takeshi [Crete Center for Theoretical Physics Department of Physics University of Crete, 71003 Heraklion (Greece)
Calculation of Neoclassical Toroidal Viscosity with a Particle Simulation in the Tokamak Magnetic Breaking Experiments
Accurate calculation of perturbed distribution function #14;?f and perturbed magnetic fi eld #14;?B is essential to achieve prediction of non-ambipolar transport and neoclassical toroidal viscosity (NTV) in perturbed tokamaks. This paper reports a study of the NTV with a #14;?f particle code (POCA) and improved understanding of magnetic braking in tokamak experiments. POCA calculates the NTV by computing #14;f with guiding-center orbit motion and using #14;B from the ideal perturbed equilibrium code (IPEC). POCA simulations are compared with experimental estimations for NTV, which are measured from angular momentum balance (DIII-D) and toroidal rotational damping rate (NSTX). The calculation shows good agreement in total NTV torque for the DIII-D discharge, where an analytic neoclassical theory also gives a consistent result thanks to relatively large aspect-ratio and slow toroidal rotations. In NSTX discharges, where the aspect-ratio is small and the rotation is fast, the theory only gives a qualitative guide for predicting NTV. However, the POCA simulation largely improves the quantitative NTV prediction for NSTX. It is discussed that a self- consistent calculation of ?#14;B using general perturbed equilibria is eventually necessary since a non-ideal plasma response can change the perturbed eld and thereby the NTV torque.
Kimin Kim, et al
Charles L Neumeyer | Princeton Plasma Physics Lab
Charles L Neumeyer Charles L Neumeyer ITER Steady State Electrical Systems WBS Manager, NSTX Project Engineer Charles Neumeyer Jr. is a registered professional engineer with more than 30 years experience in advanced technology research and project management. His experience covers functions ranging from design to procurement and conditioning. Neumeyer has managerial roles in activities associated with ITER and the National Spherical Torus Experiment Upgrade (NSTX-U). He is responsible for U.S. equipment contributions for the ITER Steady State Electrical Network, which will supply AC power to all ITER plant systems. As systems engineer for the NSTX-U, he is responsible for systems integration of the upgrade project. Interests Electromagnetic and high voltage engineering AC/DC power conditioning systems
Topological Invariants and Ground States Wavefunctions of Topological Insulators on a Torus
We define topological invariants in terms of the ground states wavefunctions on a torus. This approach leads to precisely defined formulas for the Hall conductance in four dimensions and the topological magneto-electric $\\theta$ term in three dimensions, and their generalizations in higher dimensions. They are valid in the presence of arbitrary many-body interaction and disorder. These topological invariants systematically generalize the two-dimensional Niu-Thouless-Wu formula, and will be useful in numerical calculations of disordered topological insulators and strongly correlated topological insulators including fractional topological insulators.
Zhong Wang; Shou-Cheng Zhang
Edge Mode Combinations in the Entanglement Spectra of Non-Abelian Fractional Quantum Hall States on the Torus
We present a detailed analysis of bi-partite entanglement in the non-Abelian Moore-Read fractional quantum Hall state of bosons and fermions on the torus. In particular, we show that the entanglement spectra can be decomposed into intricate combinations of different sectors of the conformal field theory describing the edge physics, and that the edge level counting and tower structure can be microscopically understood by considering the vicinity of the thin-torus limit. We also find that the boundary entropy density of the Moore-Read state is markedly higher than in the Laughlin states investigated so far. Despite the torus geometry being somewhat more involved than in the sphere geometry, our analysis and insights may prove useful when adopting entanglement probes to other systems that are more easily studied with periodic boundary conditions, such as fractional Chern insulators and lattice problems in general.
Zhao Liu; Emil J. Bergholtz; Heng Fan; Andreas M. Laeuchli
TORUS: Theory of Reactions for Unstable iSotopes - Year 1 Continuation and Progress Report
The TORUS collaboration derives its name from the research it focuses on, namely the Theory of Reactions for Unstable iSotopes. It is a Topical Collaboration in Nuclear Theory, and funded by the Nuclear Theory Division of the Office of Nuclear Physics in the Office of Science of the Department of Energy. The funding started on June 1, 2010, it will have been running for nine months by the date of submission of this Annual Continuation and Progress Report on March 1, 2011. The extent of funding was reduced from the original application, and now supports one postdoctoral researcher for the years 1 through 3. The collaboration brings together as Principal Investigators a large fraction of the nuclear reaction theorists currently active within the USA. The mission of the TORUS Topical Collaboration is to develop new methods that will advance nuclear reaction theory for unstable isotopes by using three-body techniques to improve direct-reaction calculations, and, by using a new partial-fusion theory, to integrate descriptions of direct and compound-nucleus reactions. This multi-institution collaborative effort is directly relevant to three areas of interest: the properties of nuclei far from stability; microscopic studies of nuclear input parameters for astrophysics, and microscopic nuclear reaction theory.
Arbanas, G; Elster, C; Escher, J; Mukhamedzhanov, A; Nunes, F; Thompson, I J
The Role of the Spherical Tokamak in the U.S. Fusion Energy Sciences Program Organized by J. Menard with contributions from the NSTX-U research team and US ST community members
plasma operation, while being very effective in steady- state divertor heat flux mitigation and impurity prior to D-T operation. As such, NSTX used High Harmonic Fast Wave (HHFW) RF heating (no particle, must be developed. Candidate techniques for steady-state mitigation of divertor heat and particle loads
Fast-wave Power Flow Along SOL Field Lines In NSTX nd The Associated Power Deposition Profile Across The SOL In Front Of The Antenna
Fast-wave heating and current drive efficiencies can be reduced by a number of processes in the vicinity of the antenna and in the scrape off layer (SOL). On NSTX from around 25% to more than 60% of the high-harmonic fast-wave power can be lost to the SOL regions, and a large part of this lost power flows along SOL magnetic field lines and is deposited in bright spirals on the divertor floor and ceiling. We show that field-line mapping matches the location of heat deposition on the lower divertor, albeit with a portion of the heat outside of the predictions. The field-line mapping can then be used to partially reconstruct the profile of lost fast-wave power at the midplane in front of the antenna, and the losses peak close to the last closed flux surface (LCFS) as well as the antenna. This profile suggests a radial standing-wave pattern formed by fast-wave propagation in the SOL, and this hypothesis will be tested on NSTX-U. Advanced RF codes must reproduce these results so that such codes can be used to understand this edge loss and to minimize RF heat deposition and erosion in the divertor region on ITER.
Perkins, Roy
Quantitative perturbative study of convergence to equilibrium for collisional kinetic models in the torus
For a general class of linear collisional kinetic models in the torus, including in particular the linearized Boltzmann equation for hard spheres, the linearized Landau equation with hard and moderately soft potentials and the semi-classical linearized fermionic and bosonic relaxation models, we prove explicit coercivity estimates on the associated integro-differential operator for some modified Sobolev norms. We deduce existence of classical solutions near equilibrium for the full non-linear models associated, with explicit regularity bounds, and we obtain explicit estimates on the rate of exponential convergence towards equilibrium in this perturbative setting. The proof are based on a linear energy method which combines the coercivity property of the collision operator in the velocity space with transport effects, in order to deduce coercivity estimates in the whole phase space.
Cl�ment Mouhot; Lukas Neumann
Dose rates from induced activity in the ELMO Bumpy Torus proof-of-principle device
Calculated results of the dose rates from induced activity in the enclosure of the ELMO Bumpy Torus proof-of-principle device (EBT-P) are presented. A cylindrical model of EBT-P is used. EBT-P will have a hydrogen plasma and thus the plasma will not produce neutrons, but substantial numbers of photoneutrons will be produced and it is the induced activity from these photoneutrons that is considered. The activation dose rates are presented for a variety of operating times and times after shutdown. Dose rates about 5 to 10 mrem/h at 1 h after shutdown are obtained and the major contributor to the dose rate at 1 h after shutdown is found to be /sup 24/Na (half-life=15.0 h).
Alsmiller, R.G.; Barish, J.; Barnes, J.M.; Santoro, R.T.
Dyonic BPS saturated black holes of heterotic string on a six-torus
Within effective heterotic superstring theory compactified on a six-torus we derive minimum energy (supersymmetric), static, spherically symmetric solutions, which are manifestly invariant under the target space O(6,22) and the strong-weak coupling SL(2,I\\!\\!R) duality symmetries with 28 electric and 28 magnetic charges subject to one constraint. The class of solutions with a constant axion corresponds to dyonic configurations subject to two charge constraints, with purely electric [or purely magnetic] and dyonic configurations preserving {1\\over 2} and {1\\over 4} of N=4 supersymmetry, respectively. General dyonic configurations in this class have a space-time of extreme Reissner-Nordstr\\" om black holes while configurations with more constrained charges have a null or a naked singularity.
Cvetic, M; Cveti, Mirjam; Youm, Donam
Torus equivariant spectral triples for odd dimensional quantum spheres coming from $C^*$-extensions.
The torus group $(S^1)^{\\ell+1}$ has a canonical action on the odd dimensional sphere $S_q^{2\\ell+1}$. We take the natural Hilbert space representation where this action is implemented and characterize all odd spectral triples acting on that space and equivariant with respect to that action. This characterization gives a construction of an optimum family of equivariant spectral triples having nontrivial $K$-homology class thus generalizing our earlier results for $SU_q(2)$. We also relate the triple we construct with the $C^*$-extension \\[ 0\\longrightarrow \\clk\\otimes C(S^1)\\longrightarrow C(S_q^{2\\ell+3}) \\longrightarrow C(S_q^{2\\ell+1}) \\longrightarrow 0. \\
Partha Sarathi Chakraborty; Arupkumar Pal
Hydrogen atom in crossed electric and magnetic fields: Phase space topology and torus quantization via periodic orbits
A hierarchical ordering is demonstrated for the periodic orbits in a strongly coupled multidimensional Hamiltonian system, namely the hydrogen atom in crossed electric and magnetic fields. It mirrors the hierarchy of broken resonant tori and thereby allows one to characterize the periodic orbits by a set of winding numbers. With this knowledge, we construct the action variables as functions of the frequency ratios and carry out a semiclassical torus quantization. The semiclassical energy levels thus obtained agree well with exact quantum calculations.
Stephan Gekle; J�rg Main; Thomas Bartsch; T. Uzer
NGC 5548: The AGN Energy Budget Problem and the Geometry of the Broad-Line Region and Torus
We consider in detail the spectral energy distribution (SED) and multi-wavelength variability of NGC5548. Comparison with the SEDs of other AGNs implies that the internal reddening of NGC5548 is E(B-V) = 0.17 mag. The extinction curve is consistent with the mean curve of other AGNs found by Gaskell & Benker, but inconsistent with an SMC-type reddening curve. Because most IR emission originates exterior to the broad-line region (BLR), the SED seen by the inner BLR is different from that seen by the outer BLR and from the earth. The most likely BLR covering factor is ~ 40% and it is not possible to get an overall BLR covering factor of less than 20%. This requires that the BLR is not spherically symmetric and that we are viewing through a hole. Line-continuum variability transfer functions are consistent with this geometry. The covering factor and geometry imply that near the equatorial plane the BLR covering approaches 100%. The spectrum seen by the outer regions of the BLR and by the torus is thus modified by the absorption in the inner BLR. This shielding solves the problem of observed BLR ionization stratification being much greater than implied by photoionization models. The BLR obscuration also removes the problem of the torus covering factor being greater than the BLR covering factor, and gives consistency with the observed fraction of obscured AGNs. The flux reduction at the torus also reduces the problem of AGN dust-reverberation lags giving sizes smaller than the dust-sublimation radii.
C. Martin Gaskell; Elizabeth S. Klimek; Ludmila S. Nazarova
Embedding global barrier and collective in torus network with each node combining input from receivers according to class map for output to senders
Embodiments of the invention provide a method, system and computer program product for embedding a global barrier and global interrupt network in a parallel computer system organized as a torus network. The computer system includes a multitude of nodes. In one embodiment, the method comprises taking inputs from a set of receivers of the nodes, dividing the inputs from the receivers into a plurality of classes, combining the inputs of each of the classes to obtain a result, and sending said result to a set of senders of the nodes. Embodiments of the invention provide a method, system and computer program product for embedding a collective network in a parallel computer system organized as a torus network. In one embodiment, the method comprises adding to a torus network a central collective logic to route messages among at least a group of nodes in a tree structure.
Chen, Dong; Coteus, Paul W; Eisley, Noel A; Gara, Alan; Heidelberger, Philip; Senger, Robert M; Salapura, Valentina; Steinmacher-Burow, Burkhard; Sugawara, Yutaka; Takken, Todd E
David W Johnson | Princeton Plasma Physics Lab
W Johnson W Johnson Principal Research Physicist, Head, ITER Fabrication David Johnson is a principal research physicist with broad experience in techniques and instrumentation for measuring the characteristics of magnetic fusion plasmas. He has specific expertise in laser Thomson scattering systems, and has installed and operated such systems on many fusion devices around the world. He managed a division of plasma diagnostic experts for the Tokamak Fusion Test Reactor (TFTR) and National Spherical Torus Experiment (NSTX) projects, more recently becoming the Work Breakdown Structure Team Leader for US ITER Diagnostics. He has served on numerous national and international committees related to diagnostic development. Interests Plasma diagnostics techniques and instrumentation
Finite Orbit Monte Carlo Simulation with Full Wave Fields for ICRF Wave Heating Experiments in DIII-D, NSTX, KSTAR and ITER
Bull. Am. Phys. Soc. 55, 62 (2010)52nd American Physical Society Annual Meeting of Division of Plasma Physics Chicago Illinois, US, 2010999618200
Choi, M.
Investigations of Low and Moderate Harmonic Fast Wave Physics on CDX-U
Third harmonic hydrogen cyclotron fast wave heating studies are planned in the near term on CDX-U to investigate the potential for bulk ion heating. In preparation for these studies, the available radio-frequency power in CDX-U has been increased to 0.5 MW. The operating frequency of the CDX-U radio-frequency transmitter was lowered to operate in the range of 8-10 MHz, providing access to the ion harmonic range 2* {approx} 4* in hydrogen. A similar regime is accessible for the 30 MHz radio-frequency system on the National Spherical Torus Experiment (NSTX), at 0.6 Tesla in hydrogen. Preliminary computational studies over the plasma regimes of interest for NSTX and CDX-U indicate the possibility of strong localized absorption on bulk ion species.
J. Spaleta; R. Majeski; C.K. Phillips; R.J. Dumont; R. Kaita; V. Soukhanovskii; L. Zakharov
A Compact Torus Fusion Reactor Utilizing a Continuously Generated Strings of CT's. The CT String Reactor, CTSR.
A fusion reactor is described in which a moving string of mutually repelling compact toruses (alternating helicity, unidirectional Btheta) is generated by repetitive injection using a magnetized coaxial gun driven by continuous gun current with alternating poloidal field. An injected CT relaxes to a minimum magnetic energy equilibrium, moves into a compression cone, and enters a conducting cylinder where the plasma is heated to fusion-producing temperature. The CT then passes into a blanketed region where fusion energy is produced and, on emergence from the fusion region, the CT undergoes controlled expansion in an exit cone where an alternating poloidal field opens the flux surfaces to directly recover the CT magnetic energy as current which is returned to the formation gun. The CT String Reactor (CTSTR) reactor satisfies all the necessary MHD stability requirements and is based on extrapolation of experimentally achieved formation, stability, and plasma confinement. It is supported by extensive 2D, MHD calculations. CTSTR employs minimal external fields supplied by normal conductors, and can produce high fusion power density with uniform wall loading. The geometric simplicity of CTSTR acts to minimize initial and maintenance costs, including periodic replacement of the reactor first wall.
Hartman, C W; Reisman, D B; McLean, H S; Thomas, J
Observation of lines above 2000 A in O VIII and C VI in the Princeton Large Torus due to charge-exchange processes: Diagnostic applications
Hydrogenlike oxygen and carbon lines from transitions (..delta..n = 1) between levels of high principal quantum number n, with wavelengths above 2000 A have been observed. Observations of such transitions were possible due to charge-exchange processes during neutral beam injection of hydrogen atoms into the Princeton Large Torus tokamak. The lines are O VIII 2976 A (8--7 transitions), C VI 3434 A (7--6), and C VI 5291 A (8--7). Application of these lines for ion temperature measurements and initial observations of neutral beam vertical distributions in the plasma are presented.
Suckewer, S.; Skinner, C.H.; Stratton, B.; Bell, R.; Cavallo, A.; Hosea, J.; Hwang, D.; Schilling, G.
Rack Number Assignments Location TFTR TFTR NSTX NSTX
and CTWH 590-599 Mechanical Equipment Room CMER 595, 596 FCPC TF Wing CTF1,CTF2 601-609 CTF1,CTF2 601-609 FCPC OH Wing COH1,3,5,CEF1,3,CCPC 651-658 COH1,3,5,CEF1,3,CCPC 651-658 FCPC 2nd Flr CCD Area CEF1, CEF3-003 C-Site MG Basement Red=may go or have gone away Green=change #12;
NSTX Upgrade Project Execution Plan NSTX Upgrade Project
Project. DOE Order 413.3B will provide the basis for the overall management of the Project. 1.2 Key the principles of project management and control systems outlined in this PEP and DOE Order 413.3B ("Program ..............................................................................................................................1 1.2.1 DOE-approved project documents
Project. DOE Order 413.3B will provide the basis for the overall management of the Project. 1.2 Key of project management and control systems outlined in this PEP and DOE Order 413.3B ("Program and Project ..............................................................................................................................1 1.2.1 DOE-approved project documents
Project. DOE Order 413.3B will provide the basis for the overall management of the Project. 1.2 Key of project management and control systems outlined in this PEP and DOE Order 413.3B ("Program and Project 10/12/2012 Update to WBS Level 2 Threshold (top of page 20), Change DOE Federal Project Director
TORUS: Theory of Reactions for Unstable iSotopes Annual Continuation and Progress Report Year-2: March 1, 2011 - February 29, 2012
The TORUS collaboration derives its name from the research it focuses on, namely the Theory of Reactions for Unstable iSotopes. It is a Topical Collaboration in Nuclear Theory, and funded by the Nuclear Theory Division of the Office of Nuclear Physics in the Office of Science of the Department of Energy. The funding supports one postdoctoral researcher for the years 1 through 3. The collaboration brings together as Principal Investigators a large fraction of the nuclear reaction theorists currently active within the USA. The mission of the TORUS Topical Collaboration is to develop new methods that will advance nuclear reaction theory for unstable isotopes by using three-body techniques to improve direct-reaction calculations, and, by using a new partial-fusion theory, to integrate descriptions of direct and compound-nucleus reactions. This multi-institution collaborative effort is directly relevant to three areas of interest: the properties of nuclei far from stability; microscopic studies of nuclear input parameters for astrophysics, and microscopic nuclear reaction theory.
Arbanas, G; Elster, C; Escher, J; Mukhamedzanov, A; Nunes, F; Thompson, I J
NSTX PAC-29 Meeting Debriefing
=0->%*?@%*ABB CD*ABB)B*%!"#$%-4E40-FG%15H4EI.94E 7J0E4 09:%%incremental ; ? KLMIN%O=9%P44QER B; #-09EM
current will double to 2 million amperes as a result of the upgrade. A 100-watt light bulb draws 1 amp of current. * Strategies developed for taming the intensely hot plasma...
Polymorphic-Torus Network
The memo specifies the Hot Standby Router Protocol (HSRP). The goal of the protocol is to allow hosts to appear to use a single router and to maintain connectivity even if the actual first hop router they are using fails. Multiple routers participate in this protocol and in concert create the illusion of a single virtual router. The protocol insures that one and only one of the routers is forwarding packets on behalf of the virtual router. End hosts forward their packets to the virtual router.
Status Of This; P. Morton; D. Li; Cisco Systems; Cisco Systems
Ion cyclotron heating experiments in EBT-S
Fast-wave heating and propagation experiments in the ion cyclotron range of frequencies (ICRF) have been carried out on EBT-S under steady-state conditions at power levels up to 20 kW and under pulsed conditions at power levels up to 100 kW. The waves were launched using a single Faraday-shielded loop antenna installed on the midplane of one of the 24 cavity sectors. Substantial ion heating was observed at frequencies above the second harmonic for hydrogen plasmas and at frequencies above the third harmonic for deuterium plasmas, corresponding with the onset of wave propagation around the torus. The heating under these conditions is anomalous. In the case of deuterium plasmas, a small residual concentration (2 to 5%) of hydrogen was heated, but this component did not appear to affect the deuterium heating.
Baity, F.W.; Davis, W.A.; Eldridge, O.C.; Glowienka, J.C.; Hillis, D.L.; Rasmussen, D.A.; Richards, R.K.; Mullen, J.H.; Owens, T.L.
Fusion scientists gear up to learn how to harness plasma energy | Princeton
Living on the edge Living on the edge Fusion scientists gear up to learn how to harness plasma energy By Kitta MacPherson March 30, 2011 Tweet Widget Facebook Like Google Plus One Researchers working on an advanced experimental fusion machine are readying experiments that will investigate a host of scientific puzzles, including how heat escapes as hot magnetized plasma, and what materials are best for handling intense plasma powers. Scientists conducting research on the National Spherical Torus Experiment (NSTX) at the U.S. Department of Energy's Princeton Plasma Physics Laboratory (PPPL) have mapped out a list of experiments to start in July and run for eight months. The experimental machine is designed to deepen understanding of how plasmas can be mined for energy. A major topic of investigation by scientists for the coming round of
Mechanism of Radial Redistribution of Energetic Trapped Ions Due to m=2/n=1 Internal Reconnection in Joint European Torus Shear Optimized Plasmas
Internal radial redistribution of MeV energy ICRF-driven hydrogen minority ions was inferred from neutral particle analyzer measurements during large amplitude MHD activity leading to internal reconnection in Shear Optimized plasmas in the Joint European Torus (JET). A theory is developed for energetic ion redistribution during a reconnection driven by an m=2/n=1 internal kink mode. Plasma motion during reconnection generates an electric field which can change the energy and radial position of the energetic ions. The magnitude of ion energy change depends on the value of the safety factor at the plasma core from which the energetic ions are redistributed. A relation is found for corresponding change in canonical momentum. P(subscript phi), which leads to radial displacement of the ions. The model yields distinctive new features of energetic ion redistribution under such conditions. Predicted characteristics of ion redistribution are compared with the NPA measurements, and good correlation is found. Sometimes fast ions were transported to the plasma edge due to interaction with a long-lived magnetic island which developed after the reconnection and had chirping frequency in the laboratory frame. Convection of resonant ions trapped in a radially moving phase-space island is modeled to understand the physics of such events.
N.N. Gorelenkov; A. Gondhalekar; A.A. Korotkov; S.E. Sharapov; D. Testa; and Contributors to the EFDA-JET Workprogramme
TRIO experiment
The TRIO experiment is a test of in-situ tritium recovery and heat transfer performance of a miniaturized solid breeder blanket assembly. The assembly (capsule) was monitored for temperature and neutron flux profiles during irradiation and a sweep gas flowed through the capsule to an anaytical train wherein the amounts of tritium in its various chemical forms were determined. The capsule was designed to operate at different temperatures and sweep gas conditions. At the end of the experiment the amount of tritium retained in the solid was at a concentration of less than 0.1 wppM. More than 99.9% of tritium generated during the experiment was successfully recovered. The results of the experiment showed that the tritium inventories at the beginning and at the end of the experiment follow a relationship which appears to be characteristic of intragranular diffusion.
Clemmer, R.G.; Finn, P.A.; Malecha, R.F.; Misra, B.; Billone, M.C.; Bowers, D.L.; Fischer, A.K.; Greenwood, L.R.; Mattas, R.F.; Tam, S.W.
Robert Kaita | Princeton Plasma Physics Lab
Kaita Kaita Principal Research Physicist, P.I., LTX Robert (Bob) Kaita is the head of plasma diagnostic operations and acting head of boundary physics operations for the National Spherical Torus Experiment (NSTX). Kaita is also a co-principal investigator of the Lithium Tokamak Experiment (LTX). He is a Fellow of the American Physical Society and a recipient of the Kaul Foundation Prize for Excellence in Plasma Physics Research. He has supervised the research of many students in the PPPL Program in Plasma Physics in the Department of Astrophysical Sciences at Princeton University. Interests Neutral beam and radiofrequency plasma heating Plasma diagnostics Plasma-surface interactions Solid and liquid plasma-facing components Contact Information Phone: 609-243-3275
Mechanisms of Stochastic Diffusion of Energetic Ions in Spherical Tori
Stochastic diffusion of the energetic ions in spherical tori is considered. The following issues are addressed: (I) Goldston-White-Boozer diffusion in a rippled field; (ii) cyclotron-resonance-induced diffusion caused by the ripple; (iii) effects of non-conservation of the magnetic moment in an axisymmetric field. It is found that the stochastic diffusion in spherical tori with a weak magnetic field has a number of peculiarities in comparison with conventional tokamaks; in particular, it is characterized by an increased role of mechanisms associated with non-conservation of the particle magnetic moment. It is concluded that in current experiments on National Spherical Torus eXperiment (NSTX) the stochastic diffusion does not have a considerable influence on the confinement of energetic ions.
Ya.I. Kolesnichenko; R.B. White; Yu.V. Yakovenko
Approved Experiments
Cycle 31OCT97 Exp Spokesperson Experiment Title Days 666 Clark Magnetic Rotation in 104Sn 5 667 Janssens Unsafe COULEX of the 240Pu Nucleus 3 670 Smith Exotic Structures in very...
'Optical' soft x-ray arrays for fluctuation diagnostics in magnetic fusion energy experiments
We are developing large pixel count, fast ({>=}100 kHz) and continuously sampling soft x-ray (SXR) array for the diagnosis of magnetohydrodynamics (MHD) and turbulent fluctuations in magnetic fusion energy plasmas. The arrays are based on efficient scintillators, high thoughput multiclad fiber optics, and multichannel light amplification and integration. Compared to conventional x-ray diode arrays, such systems can provide vastly increased spatial coverage, and access to difficult locations with small neutron noise and damage. An eight-channel array has been built using columnar CsI:Tl as an SXR converter and a multianode photomultiplier tube as photoamplifier. The overall system efficiency is measured using laboratory SXR sources, while the time response and signal-to-noise performance have been evaluated by recording MHD activity from the spherical tori (ST) Current Drive Experiment-Upgrade and National Spherical Torus Experiment, both at Princeton Plasma Physics Laboratory.
Delgado-Aparicio, L.F.; Stutman, D.; Tritz, K.; Finkenthal, M.; Kaita, R.; Roquemore, L.; Johnson, D.; Majeski, R. [Johns Hopkins University, Department of Physics and Astronomy, Plasma Spectroscopy Group, Bloomberg Center 3400 N. Charles Street, Baltimore, Maryland 21218 (United States); Princeton University Plasma Physics Laboratory, P. O. Box 451, Princeton, New Jersey 08543 (United States)
Ex-vessel remote maintenance development plans for the Burning Plasma Experiment
Remote maintenance (RM) is fundamental to the basic design requirements of the Burning Plasma Experiment (BPX), and an extensive RM development and demonstration program is planned to meet these requirements. The program first draws from the experience base that exists in the fission community and Europe's Joint European Torus (JET) Project. Successful solutions are applied where possible and, in many cases, improved in order to achieve the performance demanded by a multiyear program that must be capable of efficiently executing RM procedures. Early, concurrent efforts in the design and fabrication of prototype remote handling (RH) equipment, remote tooling, and maintainable machine components will precede an extensive use of mock-up equipment in order to test, develop, and demonstrate the technology. 7 refs,. 5 figs.
Burgess, T.W.; Davis, F.C.
Simulation of tokamak SOL and divertor region including heat flux mitigation by gas puffing
Two-dimensional (2D), scrape-off layer (SOL)-divertor transport simulations are performed using the integrated plasma-neutral-impurity code KTRAN developed at Seoul National University. Firstly, the code is applied to reproduce a National Spherical Torus eXperiment (NSTX) discharge by using the prescribed transport coefficients and the boundary conditions obtained from the experiment. The plasma density, the heat flux on the divertor plate, and the D (alpha) emission rate profiles from the numerical simulation are found to follow experimental trends qualitatively. Secondly, predictive simulations are carried out for the baseline operation mode in Korea Superconducting Tokamak Advanced Research (KSTAR) to predict the heat flux on the divertor target plates. The stationary peak heat flux in the KSTAR baseline operation mode is expected to be 6.5 MW/m(2) in the case of an orthogonal divertor. To study the mitigation of the heat flux, we investigated the puffing effects of deuterium and argon gases. The puffing position is assumed to be in front of the strike point at the outer lower divertor plate. In the simulations, mitigation of the peak heat flux at the divertor target plates is found to occur when the gas puffing rate exceeds certain values, similar to 1.0 x 10(20) /s and similar to 5.0 x 10(18) /s for deuterium and argon, respectively. Multi-charged impurity transport is also investigated for both NSTX and KSTAR SOL and divertor regions.
Park, Jin Woo [Seoul National University, Seoul, S. Korea; Na, Y. S. [Seoul National University, Seoul, S. Korea; Hong, S. H. [National Fusion Research Institute, Daejon, South Korea; Ahn, J.W. [Oak Ridge National Laboratory (ORNL); Kim, D. K. [Agency Def Dev, Taejon, South Korea; Han, Hyunsun [National Fusion Research Institute, Taejon, South Korea; Shim, Seong Bo [Pusan National University, Busan, Korea; Lee, Hae June [Pusan National University, Busan, Korea
Facilities | U.S. DOE Office of Science (SC)
Facilities Facilities Fusion Energy Sciences (FES) FES Home About Research Facilities ITER External link DIII-D External link National Spherical Torus Experiment (NSTX) External link Alcator C-Mod External link Science Highlights Benefits of FES Funding Opportunities Fusion Energy Sciences Advisory Committee (FESAC) News & Resources Contact Information Fusion Energy Sciences U.S. Department of Energy SC-24/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-4941 F: (301) 903-8584 E: email@example.com More Information » Facilities Print Text Size: A A A RSS Feeds FeedbackShare Page ITER ITER (Latin for "the way") is a critical step between today's studies of plasma physics and tomorrow's fusion power plants producing electricity and hydrogen. An unprecedented international collaboration of scientists
Ongoing Projects | U.S. DOE Office of Science (SC)
Current Projects Current Projects Project Assessment (OPA) OPA Home About Project Management SC Projects Review Dates (updated November 2013) Project Construction Photos Completed Projects Current Projects Other Links SC Federal Project Directors (FPD) and FPD Resources Contact Information Project Assessment U.S. Department of Energy SC-28/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-4840 F: (301) 903-8520 E: email@example.com Project Construction Photos Current Projects Print Text Size: A A A RSS Feeds FeedbackShare Page Photos of current SC Projects 12 GeV CEBAF Upgrade .pdf file (3.2MB) Daya Bay .pdf file (1.0MB) National Spherical Torus Experiment (NSTX) .pdf file (841KB) National Synchrotron Light Source II (NSLS II) .pdf file (6.4MB)
Ideal magnetohydrodynamic simulations of unmagnetized dense plasma jet injection into a hot strongly magnetized plasma
We present results from three-dimensional ideal magnetohydrodynamic simulations of unmagnetized dense plasma jet injection into a hot strongly magnetized plasma, with the aim of providing insight into core fueling of a tokamak with parameters relevant for ITER (International Thermonuclear Experimental Reactor) and NSTX (National Spherical Torus Experiment). Unmagnetized jet injection is similar to compact toroid injection but with higher possible injection density and total mass, as well as a potentially smaller footprint for the injector hardware. Our simulation results show that the unmagnetized dense jet is quickly magnetized upon injection. The penetration depth of the jet into the tokamak plasma is mostly dependent on the jet's initial kinetic energy while the jet's magnetic field determines its interior evolution. A key requirement for spatially precise fueling is for the jet's slowing-down time to be less than the time for the perturbed tokamak magnetic flux to relax due to magnetic reconnection. Thus ...
Liu, Wei
He Puff System For Dust Detector Upgrade
Local detection of surface dust is needed for the safe operation of next-step magnetic fusion devices such as ITER. An electrostatic dust detector, based on a 5 cm x 5 cm grid of interlocking circuit traces biased to 50 V, has been developed to detect dust on remote surfaces and was successfully tested for the first time on the National Spherical Torus Experiment (NSTX). We report on a helium puff system that clears residual dust from this detector and any incident debris or fibers that might cause a permanent short circuit. The entire surface of the detector was cleared of carbon particles by two consecutive helium puffs delivered by three nozzles of 0.45 mm inside diameter. The optimal configuration was found to be with the nozzles at an angle of 30o with respect to the surface of the detector and a helium backing pressure of 6 bar. __________________________________________________
B. Rais, C.H. Skinner A.L. Roquemore
SANE experiment
The Spin Asymmetries of the Nucleon Experiment (SANE) is a measurement of parallel and near-perpendicular double spin asymmetries in an inclusive electron scattering. The main goal of the experiment was to measure A{sub {parallel}} and A{sub 80} and extract the spin asymmetries of the proton A{sub 1}{sup p}, A{sub 2}{sup p} and spin structure functions g{sub 1}{sup p} and g{sub 2}{sup p}. Using the Thomas Jefferson National Accelerator Facility's polarized electron beam and the University of Virginia's polarized frozen ammonia ({sup 14}NH{sub 3}) target in Hall C, the experiment ran in 2009, collecting data in a Q{sup 2} region from 2.5 to 6.5 GeV{sup 2} and between Bjorken x of 0.3 to 0.8. Particle detection was accomplished using the Big Electron Telescope Array (BETA), a novel non-magnetic detector. This talk will address the progress of the analysis designed to extract the proton spin asymmetries and structure functions. Preliminary results will be presented.
H. Baghdasaryan, SANE Collaboration
Current Trends, DC, 3/24-28/03Progress towards Energy Supported by
Current Trends, DC, 3/24-28/03Progress towards Energy Supported by Columbia U Comp-X GA INEL JHU-term research plan #12;Current Trends, DC, 3/24-28/03Progress towards Energy Spherical Torus Offers High Trends, DC, 3/24-28/03Progress towards Energy NSTX Is to Prove Scientific Principle (PoP) of the Extended
--No Title--
Experiment (NSTX). They have been very supportive in addressing issues with regard to ITER design and operation. PPPL has been very supportive of the Office of Fusion Energy...
PPPL wins R&D 100 Award | Princeton Plasma Physics Lab
right) Jon Menard, the NSTX program director, and Vlad Soukhanovskii, who designed and led the experiments. (Photo by Elle Starkman, PPPL Office of Communications) Award winners:...
Overview of the Initial NSTX Experimental Results
. Takase, ,H. Hayashiya, S. Shiraiwa, Univ. Tokyo, Tokyo, Japan N. Nishino, Hiroshima Univ., Hiroshima
Topics covered include: ray tracing and Fokker-Planck coupling; relativistic and electromagnetic effects in EBW damping (ray-tracing); O-X-EBW mode conversion efficiency limit due to finite beam divergence; general prospects for electron Bernstein wave heating and current drive in spherical tokamaks; sensitivity of EBW H&CD; collisional effects on EBW coupling; and EBW propagation in a high-temperature plasma.
Linda Vahala
Princeton Plasma Physics Laboratory NSTX Machine Proposal
Procedure (ENG-021) Confined Space Permit DCA/DCN (OP-AD-104) Pre-job brief (OP-AD-79) ATI Walkdown USQD (OP: reload shot 115326 #12;DIAGNOSTIC CHECKLIST OP-XMP-44 Diagnostic Need Desire Instructions Bolometer
Procedure (ENG-021) Confined Space Permit DCA/DCN (OP-AD-104) Pre-job brief (OP-AD-79) ATI Walkdown USQD (OP there is no confusion about times or values. #12;DIAGNOSTIC CHECKLIST Title Bring HHFW online and raise power to 6 MW OP
Procedure (ENG-021) Confined Space Permit DCA/DCN (OP-AD-104) Pre-job brief (OP-AD-79) ATI Walkdown USQD (OP and diagnostic capabilities: Physics Operations Request and Diagnostic Checklist are attached. Diagnostic;Diagnostic Checklist OP-XMP-46 Diagnostic Need Desire Instructions Bolometer tangential array Bolometer
Neutral Beam Armor for NSTX Upgrade
In-Vessel Components - FW, Blanket, Shield & VV / Proceedings of the Nineteenth Topical Meeting on the Technology of Fusion Energy (TOFE) (Part 1)
K. Tresemer; T. Stevenson; C. Priniski; J. Winkelman; L. Bryant; R. Wood
Fueling Requirements for Steady State high butane current fraction discharges
The CT injector originally used for injecting CTs into 1T toroidal field discharges in the TdeV tokamak was shipped PPPL from the Affiliated Customs Brokers storage facility in Montreal during November 2002. All components were transported safely, without damage, and are currently in storage at PPPL, waiting for further funding in order to begin advanced fueling experiments on NSTX. The components are currently insured through the University of Washington. Several technical presentations were made to investigate the feasibility of the CT injector installation on NSTX. These technical presentations, attached to this document, were: (1) Motivation for Compact Toroida Injection in NSTX; (2) Assessment of the Engineering Feasibility of Installing CTF-II on NSTX; (3) Assessment of the Cost for CT Installation on NSTX--A Peer Review; and (4) CT Fueling for NSTX FY 04-08 steady-state operation needs.
Review of D-T Experiments Relevant to Burning Plasma lssues
Progress in the performance of tokamak devices has enabled not only the production of significant bursts of fusion energy from deuterium-tritium (D-T) plasmas in the Tokamak Fusion Test Reactor (TFTR) and the Joint European Torus (JET) but, more importantly, the initial study of the physics of burning magnetically confined plasmas. TFTR and JET, in conjunction with the worldwide fusion effort, have studied a broad range of topics including magnetohydrodynamic stability, transport, wave-particle interactions, the confinement of energetic particles, and plasma boundary interactions. D-T experiments differ in three principal ways from previous experiments: isotope effects associated with the use of deuterium-tritium fuel, the presence of fusion-generated alpha particles, and technology issues associated with tritium handling and increased activation. The effect of deuterium-tritium fuel and the presence of alpha particles are reviewed and placed in the perspective of the much larger worldwide database using deuterium fuel and theoretical understanding. Both devices have contributed substantially in addressing the scientific and technical issues associated with burning plasmas. However, future burning plasma experiments will operate with larger ratios of alpha heating power to auxiliary power and will be able to access additional alpha-particle physics issues. The scientific opportunities for extending our understanding ofburning plasmas beyond that provided by current experiments are described. Keywords: deuterium-tritium, alpha-particle physics, isotope scaling, ICRF heating, JET, TFTR
Hawryluk R. J
Princeton Plasma Physics Laboratory Annual Site Environmental Report for Calendar Year 1999
The results of the 1999 environmental surveillance and monitoring program for the Princeton Plasma Physics Laboratory (PPPL) are presented and discussed. The purpose of this report is to provide the U.S. Department of Energy and the public with information on the level of radioactive and non-radioactive pollutants (if any) that are added to the environment as a result of PPPL's operations. The report also summarizes environmental initiatives, assessments, and programs that were undertaken in 1999. The Princeton Plasma Physics Laboratory has engaged in fusion energy research since 1951. The long-range goal of the U.S. Magnetic Fusion Energy Research Program is to create innovations to make fusion power a practical reality--an alternative energy source. 1999 marked the first year of National Spherical Torus Experiment (NSTX) operations and Tokamak Fusion Test Reactor (TFTR) dismantlement and deconstruction activities. A collaboration among fourteen national laboratories, universities, and research institutions, the NSTX is a major element in the U.S. Fusion Energy Sciences Program. It has been designed to test the physics principles of spherical torus (ST) plasmas. The ST concept could play an important role in the development of smaller, more economical fusion reactors. With its completion within budget and ahead of its target schedule, NSTX first plasma occurred on February 12, 1999. The 1999 performance of the Princeton Plasma Physics Laboratory was rated ''outstanding'' by the U.S. Department of Energy in the Laboratory Appraisal report issued early in 2000. The report cited the Laboratory's consistently excellent scientific and technological achievements, its successful management practices, and included high marks in a host of other areas including environmental management, employee health and safety, human resources administration, science education, and communications. Groundwater investigations continued under a voluntary agreement with the New Jersey Department of Environmental Protection. PPPL monitored for the presence of non-radiological contaminants, mainly volatile organic compounds (components of degreasing solvents). Monitoring revealed the presence of low levels of volatile organic compounds in an area adjacent to PPPL. Also, PPPL's radiological monitoring program characterized the ambient, background levels of tritium in the environment and from the TFTR stack; the data are presented in this report.
Virginia Finley
Princeton Plasma Physics Laboratory Annual Site Environmental Report for Calendar Year 2000
The results of the 2000 environmental surveillance and monitoring program for the Princeton Plasma Physics Laboratory (PPPL) are presented and discussed. The purpose of this report is to provide the U.S. Department of Energy and the public with information on the level of radioactive and nonradioactive pollutants (if any) that are added to the environment as a result of PPPL's operations. The report also summarizes environmental initiatives, assessments, and programs that were undertaken in 2000. The Princeton Plasma Physics Laboratory has engaged in fusion energy research since 1951. The long-range goal of the U.S. Magnetic Fusion Energy Research Program is to create innovations to make fusion power a practical reality -- an alternative energy source. The year 2000 marked the second year of National Spherical Torus Experiment (NSTX) operations and Tokamak Fusion Test Reactor (TFTR) dismantlement and deconstruction activities. A collaboration among fourteen national laboratories, universities, and research institutions, the NSTX is a major element in the U.S. Fusion Energy Sciences Program. It has been designed to test the physics principles of spherical torus (ST) plasmas. The ST concept could play an important role in the development of smaller, more economical fusion power plants. With its completion within budget and ahead of its target schedule, NSTX first plasma occurred on February 12, 1999. In 2000, PPPL's radiological environmental monitoring program measured tritium in the air at on-site and off-site sampling stations. PPPL is capable of detecting small changes in the ambient levels of tritium by using highly sensitive monitors. The operation of an in-stack monitor located on D-site is a requirement of the National Emission Standard for Hazardous Air Pollutants (NESHAPs) regulations with limits set by the Environmental Protection Agency (EPA). Also included in PPPL's radiological environmental monitoring program, are precipitation, surface, ground, a nd waste water monitoring. Groundwater investigations continued under a voluntary agreement with the New Jersey Department of Environmental Protection. PPPL monitored for the presence of nonradiological contaminants, mainly volatile organic compounds (components of degreasing solvents). Monitoring revealed the presence of low levels of volatile organic compounds in an area adjacent to PPPL. Also, PPPL's radiological monitoring program characterized the ambient, background levels of tritium in the environment and from the D-site stack; the data are presented in this report.
Virginia L. Finley
to Quizzes 3 Introduction to Basic Components 4 Experiment #1: The Light Bulb 8 More About Resistors 10 Detector 17 Introduction to Capacitors 18 Experiment #8: Slow Light Bulb 20 Experiment #9: Small Dominates Light Bulbs 26 Introduction to Transistors 27 Experiment #14: The Electronic Switch 28 Experiment #15
Kachroo, Pushkin
Operating Experience Summaries
Operating Experience Summaries The Office of Health, Safety and Security (HSS) Office of Analysis publishes the Operating Experience Summary to exchange lessons-learned information...
Fermilab | Science at Fermilab | Experiments & Projects | Experiments...
Particle Physics News Image Bank Fermilab in the News Quantum Diaries In this Section: Energy Frontier Intensity Frontier Cosmic Frontier Experiments at the Cosmic Frontier How...
NSTX Upgrade Project Final Design Review June 22 -24, 2011 1 NSTX Supported by
Photonics New York U Old Dominion U ORNL PPPL PSI Princeton U Purdue U SNL Think Tank, Inc. UC Davis UC Bakeout Gas Injection Cooling Water · Requirements · Description of the Design · Previous Chits · Requirements See Circuit: Resistance calculated of the vessel part 324uOhms Total resistance up to flag
Study of Thermonuclear Alfven Instabilities in Next Step Burning Plasma Experiments
A study is presented for the stability of alpha-particle driven shear Alfven Eigenmodes (AE) for the normal parameters of the three major burning plasma proposals, ITER (International Thermonuclear Experimental Reactor), FIRE (Fusion Ignition Research Experiment), and IGNITOR (Ignited Torus). A study of the JET (Joint European Torus) plasma, where fusion alphas were generated in tritium experiments, is also included to attempt experimental validation of the numerical predictions. An analytic assessment of Toroidal AE (TAE) stability is first presented, where the alpha particle beta due to the fusion reaction rate and electron drag is simply and accurately estimated in 7-20 keV plasma temperature regime. In this assessment the hot particle drive is balanced against ion-Landau damping of the background deuterons and electron collision effects and stability boundaries are determined. Then two numerical studies of AE instability are presented. In one the High-n stability code HINST is used . This code is capable of predicting instabilities of low and moderately high frequency Alfven modes. HINST computes the non-perturbative solution of the Alfven eigenmodes including effects of ion finite Larmor radius, orbit width, trapped electrons etc. The stability calculations are repeated using the global code NOVAK. We show that for these tokamaks the spectrum of the least stable AE modes are TAE that appear at medium-/high-n numbers. In HINST TAEs are locally unstable due to the alphas pressure gradient in all the devices under the consideration except IGNITOR. However, NOVAK calculations show that the global mode structure enhances the damping mechanisms and produces stability in all configurations considered here. A serious question remains whether the perturbation theory used in NOVAK overestimates the stability predictions, so that it is premature to conclude that the nominal operation of all three proposals are stable to AEs. In addition NBI ions produce a strong stabilizing effect for JET. However, in ITER the beam energies needed to penetrate to the core must be high so that a diamagnetic drift frequency comparable to that of the alpha particles is produced by the beam ions which induces a destabilizing effect.
N.N. Gorelenkov; H.L. Berk; R. Budny; C.Z. Cheng; G.-Y. Fu; W.W. Heidbrink; G. Kramer; D. Meade; and R. Nazikian
Particle Physics Experiment
What Is A Particle Physics Experiment? The word "experiment" often makes people envision a scientist in white lab coat and goggles walking into the lab, pouring some test tubes...
Tropical Ocean Circulation Experiments
A primitive equation model of the equatorial Pacific Ocean was forced by realistic wind stress distributions over decades. Results were presented for a set of two experiments. In the first experiment the model was forced by an objectively ...
Mojib Latif
COR Summary of Experience
Energy.gov (U.S. Department of Energy (DOE)) Indexed Site
COR SUMMARY OF EXPERIENCE COR SUMMARY OF EXPERIENCE Effective January 1, 2012 CORs who are applying for certification must demonstrate past contracting, acquisition, procurement, program/project management, and general business experience. This experience is based on a set of competencies. Some of the competencies are listed below to use as a reference when you are documenting your previous experience. Use this template to document your experience. Experience should be supported by a written confirmation from the cognizant Contracting Officer/Contract Specialist showing the contract number, title and date(s) to which the experience applied. Once you have completed this document, please forward it and its supporting statement(s) to your Site Acquisition Career Manager (SACM) as part of your application for COR certification.
Portable controls experiments
Experiments for controls classes like MIT's 2.004 require large lab setups and expensive equipment such as oscilloscopes and function generators. We developed a series of controls experiments based on National Instruments' ...
Larson, Richard Winston
Research Experience for Teachers
... Research Experience for Teachers (RET) program at NIST. NIST launches an initiative designed to give middle school science ...
Fundamental neutrino experiments
We review fundamental open problems in neutrino physics and propose two basic experiments for their possible resolution.
Ruggero Maria Santilli
IRLIB: Information Retrieval Experiment
IRLIB logo, INFORMATION RETRIEVAL EXPERIMENT. By Karen Sparck Jones Book published in 1981 that gives an overview ...
Princeton Plasma Physics Laboratory Annual Site Environmental Report for Calendar Year 1997
The results of the 1997 environmental surveillance and monitoring program for the Princeton Plasma Physics Laboratory (PPPL) are presented and discussed. The purpose of this report is to provide the U.S. Department of Energy and the public with information on the level of radioactive and non-radioactive pollutants, if any, that are added to the environment as a result of PPPL's operations. During Calendar Year 1997, PPPL's Tokamak Fusion Test Reactor (TFTR) completed fifteen years of fusion experiments begun in 1982. Over the course of three and half years of deuterium-tritium (D-T) plasma experiments, PPPL set a world record of 10.7 million watts of controlled fusion power, more than 700 tritium shots pulsed into the reactor vessel generating more than 5.6 x 1020 neutron and 1.6 gigajoules of fusion energy and researchers studied plasma science experimental data, which included "enhanced reverse shear techniques." As TFTR was completing its historic operations, PPPL participated with the Oak Ridge National Laboratory, Columbia University, and the University of Washington (Seattle) in a collaboration effort to design the National Spherical Torus Experiment (NSTX). This next device, NSTX, is located in the former TFTR Hot Cell on D site, and it is designed to be a smaller and more economical torus fusion reactor. Construction of this device began in late 1997, and first plasma in scheduled for early 1999. For 1997, the U.S. Department of Energy in its Laboratory Appraisal report rated the overall performance of Princeton Plasma Physics Laboratory as "excellent." The report cited the Laboratory's consistently excellent scientific and technological achievements and its successful management practices, which included high marks for environmental management, employee health and safety, human resources administration, science education, and communications. Groundwater investigations continued under a voluntary agreement with the New Jersey Department of Environmental Protection. PPPL monitored the presence of non-radiological contaminants, mainly volatile organic compounds (components of degreasing solvents). Monitoring revealed the presence of low levels of volatile organic compounds in an adjacent area to PPPL. Also, PPPL's radiological monitoring program characterized the ambient, background levels of tritium in the environment and from the TFTR stack; the data are presented in this report.
Finley, V.L. and Levine, J.D.
Transformer Ratio Enhancement Experiment
TRANSFORMER RATIO ENHANCEMENT EXPERIMENT A. Kanareykin, Euclid Concepts LLC, Solon, OH 44139, USA W. Gai, J. G. Power. ANL, Argonne, IL, 60439, USA E. Nenasheva, Ceramics Ltd., St....
The GLUEX Experiment
The GLUEX experiment to be constructed in the new Hall D at Jefferson Lab as part of the 12 GeV upgrade
M. R. Shepherd; on behalf of the GLUEX Collaboration
Sharing Smart Grid Experiences
Sharing Smart Grid Experiences through Performance Feedback March 31, 2011 DOENETL- DE-FE0004001 U.S. Department of Energy Office of Electricity Delivery and Energy Reliability...
Franklin: User Experiences
The newest workhorse of the National Energy Research Scientific Computing Center is a Cray XT4 with 9,736 dual core nodes. This paper summarizes Franklin user experiences from friendly early user period to production period. Selected successful user stories along with top issues affecting user experiences are presented.
National Energy Research Supercomputing Center; He, Yun (Helen); Kramer, William T.C.; Carter, Jonathan; Cardo, Nicholas
Experiment 2 Meter Circuits
1 Experiment 2 Meter Circuits Even in these days of digital circuitry, the d'Arsonval meter to stress a spring. The strain of the spring is read as a deflection of a scale. Most d'Arsonval meter the meter. In this experiment, the basic d'Arsonval meter movement and simple passive circuitry will be used
King, Roger
COR SUMMARY OF EXPERIENCE Effective January 1, 2012, the Office of Federal Procurement Policy (OFPP) added a requirement for past COR experience to qualify for FAC-COR Level II (journeyman level) and III (senior/expert level). At least 1 year of COR experience is required to qualify for Level II; 2 years for Level III. OFPP strongly advises that applicants for Level III have prior experience at Level II. Applicants with no prior experience as an appointed COR must demonstrate proficiency in the specific competencies listed below for the same time period, validated by a cognizant Contracting Officer or Contract Specialist by signature below or an accompanying e-mail. Submit this form to your Site Acquisition Career Manager (SACM) as part of your application
Radiochemical solar neutrino experiments
Radiochemical experiments have been crucial to solar neutrino research. Even today, they provide the only direct measurement of the rate of the proton-proton fusion reaction, p + p --> d + e^+ + nu_e, which generates most of the Sun's energy. We first give a little history of radiochemical solar neutrino experiments with emphasis on the gallium experiment SAGE -- the only currently operating detector of this type. The combined result of all data from the Ga experiments is a capture rate of 67.6 +/- 3.7 SNU. For comparison to theory, we use the calculated flux at the Sun from a standard solar model, take into account neutrino propagation from the Sun to the Earth and the results of neutrino source experiments with Ga, and obtain 67.3 ^{+3.9}_{-3.5} SNU. Using the data from all solar neutrino experiments we calculate an electron neutrino pp flux at the earth of (3.41 ^{+0.76}_{-0.77}) x 10^{10}/(cm^2-s), which agrees well with the prediction from a detailed solar model of (3.30 ^{+0.13} _{-0.14}) x 10^{10}/(cm^2-s). Four tests of the Ga experiments have been carried out with very intense reactor-produced neutrino sources and the ratio of observed to calculated rates is 0.88 +/- 0.05. One explanation for this unexpectedly low result is that the cross section for neutrino capture by the two lowest-lying excited states in 71Ge has been overestimated. We end with consideration of possible time variation in the Ga experiments and an enumeration of other possible radiochemical experiments that might have been.
V. N. Gavrin; B. T. Cleveland
Russian Grouting Experience
The final report on Russian Grouting experience provided an opportunity for international cooperation and access to Russian grouting/waste form experience. the data on radiolytic gas generation from grout mixtures was already used in evaluation of the source of hydrogen and methane generation detected in the sampling ports around the SRS high-level waste tanks in 2002. The concept of venting the radiolytic gases from a waste form by adding porous aggregate is being considered for future cement-based TRU waste forms at SRS. The objectives of this work were to document the Russian experience on grouting for waste forms and tank closures or other decommissioning applications.
Langton, C.A.
Reactor Neutrino Experiments
Precisely measuring $\\theta_{13}$ is one of the highest priority in neutrino oscillation study. Reactor experiments can cleanly determine $\\theta_{13}$. Past reactor neutrino experiments are reviewed and status of next precision $\\theta_{13}$ experiments are presented. Daya Bay is designed to measure $\\sin^22\\theta_{13}$ to better than 0.01 and Double Chooz and RENO are designed to measure it to 0.02-0.03. All are heading to full operation in 2010. Recent improvements in neutrino moment measurement are also briefed.
Jun Cao
BNL | Completed ATF Experiments
Completed / Terminated ATF Experiments Completed / Terminated ATF Experiments AE01 - Micro-undulator FEL Experiment. Spokesperson: I. Ben-Zvi, BNL. (1992 - 1997) AE02. - Inverse FEL Accelerator. Spokesperson: A. van Steenbergen, BNL. [Yale, Columbia]. (1992-1997) AE03 - Laser Grating Accelerator Experiment. Spokesperson: R. Fernow, BNL. [Princeton, LANL]. (1992- 1996) AE05 - Nonlinear-Compton Scattering. Spokesperson: K. McDonald, Princeton (1992-) AE06 - Inverse Cherenkov Acceleration. Spokesperson: W. Kimura, STI Optronics. [UCSB,BNL]. (1992-1997) AE08 - Far Infrared Radiation Source. Spokesperson J. Walsh, Dartmouth. [Oxford, BNL]. (1992 - 1994) AE09. - Photocathode R&D. Spokesperson: T. Rao, BNL. (1992 - ) AE10. - High Gain Harmonic Generation FEL. Spokesperson: L.H. Yu, BNL. [ANL] (1992 - 2001)
Complete Experiment Safety Documentation
Pressure limits of an axisymmetric torus
In order to clarify the pressure limit of a toroidal plasma equilibrium in a three-dimensional geometry, an azimuthally symmetric toroidal plasma was considered. In a tokamak-like plasma, the net toroidal current is necessary for a finite ..beta.. plasma equilibrium. If external conductors are used to provide the rotational transform, iota, the plasma pressure is limited to ..beta.. = (iota/2..pi..)/sup 2//2A, where A is the aspect ratio.
Yoshikawa, S.
Chern-Simons Theory on the Torus
We compute explicitly the Schr\\"odinger picture space of states of SU(2) Chern-Simons theory on $T^2\\times R$ in the presence of temporal Wilson lines. Relation with Friedan-Shenker bundle of conformal field theory and the existence of a projective flat connection on this bundle is discussed. Talk given by the first author at the XIX International Colloquium on Group Theoretical Methods in Physics, Salamanca (Spain), June 29-July 4, 1992
Falceto, F
Princeton Plasma Physics Laboratory Annual Site Environmental Report for Calendar Year 2001
The purpose of this report is to provide the U.S. Department of Energy (DOE) and the public with information on the level of radioactive and nonradioactive pollutants (if any) that are added to the environment as a result of the Princeton Plasma Physics Laboratory's (PPPL) operations. The results of the 2001 environmental surveillance and monitoring program for PPPL are presented and discussed. The report also summarizes environmental initiatives, assessments, and programs that were undertaken in 2001. PPPL has engaged in fusion energy research since 1951. The vision of the Laboratory is to create innovations to make fusion power a practical reality--a clean, alternative energy source. The Year 2001 marked the third year of National Spherical Torus Experiment (NSTX) operations and Tokamak Fusion Test Reactor (TFTR) dismantlement and deconstruction activities. A collaboration among fourteen national laboratories, universities, and research institutions, the NSTX is a major element in the U.S. Fusion Energy Sciences Program. It has been designed to test the physics principles of spherical torus (ST) plasmas. The ST concept could play an important role in the development of smaller, more economical fusion reactors. In 2001, PPPL's radiological environmental monitoring program measured tritium in the air at on- and off-site sampling stations. PPPL is capable of detecting small changes in the ambient levels of tritium by using highly sensitive monitors. The operation of an in-stack monitor located on D-site is a requirement of the National Emission Standard for Hazardous Air Pollutants (NESHAPs) regulations; also included in PPPL's radiological environmental monitoring program, are water monitoring--precipitation, ground-, surface-, and waste-waters. PPPL's radiological monitoring program characterized the ambient, background levels of tritium in the environment and from the D-site stack; the data are presented in this report. Groundwater monitoring continue d under a voluntary agreement with the New Jersey Department of Environmental Protection. PPPL monitored for the presence of nonradiological contaminants, mainly volatile organic compounds (components of degreasing solvents). Monitoring revealed the low levels of volatile organic compounds in an area adjacent to PPPL. In 2001, PPPL was in compliance with its permit limits for surface and sanitary discharges and had no reportable releases. Additionally, as part of DOE's program for the purchase of recycled content and other environmentally preferred products, PPPL has ranked in the excellent category of 80 to 90% of the goal.
Hershey-Chase experiment
Hershey-Chase experiment Hershey-Chase experiment Name: pei01 Location: N/A Country: N/A Date: N/A Question: I would like to know the characteristics of Griffth's experiment, and Hershey-Chase experiment. Replies: For the H-C experiment: It was designed to show that the type of virus known as a bacteriophage infected bacteria by injecting its DNA, and not by incorporating the entire virus into the bacterium. This was important because it showed that the entire replication of the virus could be coded for in the DNA of the virus, and not in the coat protein. They labeled with radioactivity the coat of the virus using one type of label 35-S, and the DNA with another, 32-P and then infected bacteria. After infection, the bacteria contained only 32-P, and no 35-S. The viruses went on to destroy the bacteria and reproduce, and the new viruses contained no 35-S in their coats. Source: Biology, 3rd ed., by Solomon et al., although the same information is in almost all texts at the college level
A three-dimensional (3D) numerical experiment of the launching of a hot and fast coronal jet followed by several violent eruptions is analyzed in detail. These events are initiated through the emergence of a magnetic flux rope from the solar interior into a coronal hole. We explore the evolution of the emerging magnetically dominated plasma dome surmounted by a current sheet and the ensuing pattern of reconnection. A hot and fast coronal jet with inverted-Y shape is produced that shows properties comparable to those frequently observed with EUV and X-ray detectors. We analyze its 3D shape, its inhomogeneous internal structure, and its rise and decay phases, lasting for some 15-20 minutes each. Particular attention is devoted to the field line connectivities and the reconnection pattern. We also study the cool and high-density volume that appears to encircle the emerged dome. The decay of the jet is followed by a violent phase with a total of five eruptions. The first of them seems to follow the general pattern of tether-cutting reconnection in a sheared arcade, although modified by the field topology created by the preceding reconnection evolution. The two following eruptions take place near and above the strong-field concentrations at the surface. They show a twisted, {Omega}-loop-like rope expanding in height, with twist being turned into writhe, thus hinting at a kink instability (perhaps combined with a torus instability) as the cause of the eruption. The succession of a main jet ejection and a number of violent eruptions that resemble mini-CMEs and their physical properties suggest that this experiment may provide a model for the blowout jets recently proposed in the literature.
Moreno-Insertis, F. [Instituto de Astrofisica de Canarias, Via Lactea, s/n, E-38205 La Laguna (Tenerife) (Spain); Galsgaard, K. [Niels Bohr Institute, University of Copenhagen, Juliane Mariesvej 30, 2100 Copenhagen (Denmark)
AGS experiments, 1988, 1989, 1990
This report contains: experimental areas layout; table of beam parameters and fluxes; experiment schedule as run''; experiment long range schedule; a listing of experiments by number; two-page summaries of each experiment begin here, also ordered by number; publications of AGS experiments; and list of experimenters.
Depken, J.C.
Venus Fly Trap Experiment
Venus Fly Trap Experiment Venus Fly Trap Experiment Name: Jeremy Bailey Status: N/A Age: N/A Location: N/A Country: N/A Date: N/A Question: My name is Jeremy Bailey, and I am a student of Dorseyville Middle School. I have been working on a science project about Venus' Fly Traps. A recent addition to the project involved designing an experiment about something I found interesting about them. However, I don't know where to get them or how to grow them in the moderate climate of Pittsburgh. Also, I don't know how a successful experiment could be designed. Replies: Jeremy, I believe Venus Fly traps can be found 'in the wild' in the coastal floodplain of the Carolinas. As far as where to buy them, look in the phonebook yellow pages under plants or houseplants and do some calling. I live in eastern Pennsylvania, and over here they even sell them in hardware stores like Hechinger's and Home Depot (in their garden departments). I don't think you will have luck trying to grow them outside, our winters here are a bit too harsh for them. From what I recall they require substantial moisture and more moderate climes. You might try looking for houseplant books at your local library for more detailed information.
Ganges valley aerosol experiment.
In June 2011, the Ganges Valley Aerosol Experiment (GVAX) began in the Ganges Valley region of India. The objective of this field campaign is to obtain measurements of clouds, precipitation, and complex aerosols to study their impact on cloud formation and monsoon activity in the region.
Kotamarthi, V.R.; Satheesh, S.K. (Environmental Science Division); (Indian Institute of Science, Bangalore, India)
The Florida Footprint experiments were a series of field programs in which perfluorocarbon tracers were released in different configurations centered on a flux tower to generate a data set that can be used to test transport and dispersion models. These models are used to determine the sources of the CO{sub 2} that cause the fluxes measured at eddy covariance towers. Experiments were conducted in a managed slash pine forest, 10 km northeast of Gainesville, Florida, in 2002, 2004, and 2006 and in atmospheric conditions that ranged from well mixed, to very stable, including the transition period between convective conditions at midday to stable conditions after sun set. There were a total of 15 experiments. The characteristics of the PFTs, details of sampling and analysis methods, quality control measures, and analytical statistics including confidence limits are presented. Details of the field programs including tracer release rates, tracer source configurations, and configuration of the samplers are discussed. The result of this experiment is a high quality, well documented tracer and meteorological data set that can be used to improve and validate canopy dispersion models.
Semantics, experience and time
The computational hypothesis, with its inherent representationalism, and the dynamical hypothesis, with its apparent absence of representations and its commitment to continuous time, stand at an impasse. It is unclear how the dynamical stance can handle ... Keywords: Computation, Experience, Invariance, Semantics, Situatedness, Time
Stephen E. Robbins
The MAJORANA Experiment
The Majorana Collaboration is assembling an array of HPGe detectors to search for neutrinoless double-beta decay in {sup 76}Ge. Initially, Majorana aims to construct a prototype module to demonstrate the potential of a future 1-tonne experiment. The design and potential reach of this prototype Demonstrator module are presented.
Guiseppe, V.E. [Univ S Dakota; Keller, C. [Univ S Dakota; Mei, D-M [Univ S Dakota; Perevozchikov, O. [Univ S Dakota; Perumpilly, G. [Univ S Dakota; Thomas, K. [Univ S Dakota; Xiang, W. [Univ S Dakota; Zhang, C. [Univ S Dakota; Aalseth, C.E. [Pacific NW Natl Lab Richland, WA; Aguayo, E. [Pacific NW Natl Lab Richland, WA; Ely, J. [Pacific NW Natl Lab Richland, WA; Fast, J.E. [Pacific NW Natl Lab Richland, WA; Hoppe, E.W. [Pacific NW Natl Lab Richland, WA; Hossbach, T.W. [Pacific NW Natl Lab Richland, WA; Keillor, M. [Pacific NW Natl Lab Richland, WA; Kephart, J.D. [Pacific NW Natl Lab Richland, WA; Kouzes, R. [Pacific NW Natl Lab Richland, WA; Miley, H.S. [Pacific NW Natl Lab Richland, WA; Mizouni, L. [Pacific NW Natl Lab Richland, WA; Myers, A.W. [Pacific NW Natl Lab Richland, WA; Reid, D. [Pacific NW Natl Lab Richland, WA; Amman, M. [Lawrence Berkeley National Laboratory (LBNL); Bergevin, M. [Lawrence Berkeley National Laboratory (LBNL); Chan, Y-D [Lawrence Berkeley National Laboratory (LBNL); Detwiler, J.A. [Lawrence Berkeley National Laboratory (LBNL); Loach, J.C. [Lawrence Berkeley National Laboratory (LBNL); Luke, P.N. [Lawrence Berkeley National Laboratory (LBNL); Martin, R.D. [Lawrence Berkeley National Laboratory (LBNL); Poon, A.W.P. [Lawrence Berkeley National Laboratory (LBNL); Prior, G. [Lawrence Berkeley National Laboratory (LBNL); Vetter, K. [Lawrence Berkeley National Laboratory (LBNL); Yaver, H. [Lawrence Berkeley National Laboratory (LBNL); Avignone, F.T. III [University of South Carolina; Creswick, R. [University of South Carolina; Farach, H. [University of South Carolina; Mizouni, L. [University of South Carolina; Avignone, Frank Titus [ORNL; Bertrand Jr, Fred E [ORNL; Capps, Gregory L [ORNL; Cooper, Reynold J [ORNL; Radford, David C [ORNL; Varner Jr, Robert L [ORNL; Wilkerson, John F [University of North Carolina, Chapel Hill; Yu, Chang-Hong [ORNL; Back, H.O. [University of North Carolina; Leviner, L. [North Carolina State University; Young, A.R. [North Carolina State University; Back (et al.), H.O. [Triangle Universities Nuclear Laboratory, Durham, NC; Bai, X. [South Dakota School of Mines and Technology; Hong, H. [South Dakota School of Mines and Technology; Howard, S. [South Dakota School of Mines and Technology; Medlin, D. [South Dakota School of Mines and Technology; Sobolev, V. [South Dakota School of Mines and Technology; Barabash, A.S. [Inst Theort & Expt Phys, Moscow, Russia; Konovalov, S.I. [Inst Theort & Expt Phys, Moscow, Russia; Vanyushin, I. [Inst Theort & Expt Phys, Moscow, Russia; Yumatov, V. [Inst Theort & Expt Phys, Moscow, Russia; Barbeau, P.S. [University of Chicago; Collar, J.I. [University of Chicago; Fields, N. [University of Chicago; Boswell (et al.), M. [Los Alamos National Laboratory (LANL); Brudanin, V. [Joint Institute for Nuclear Research, Dubna, Russia; Egorov, V. [Joint Institute for Nuclear Research, Dubna, Russia; Gusey, K. [Joint Institute for Nuclear Research, Dubna, Russia; Kochetov, O. [Joint Institute for Nuclear Research, Dubna, Russia; Shirchenko, M. [Joint Institute for Nuclear Research, Dubna, Russia; Timkin, V. [Joint Institute for Nuclear Research, Dubna, Russia; Yakushev, E. [Joint Institute for Nuclear Research, Dubna, Russia; Bugg, W. [University of Tennessee, Knoxville (UTK); Efremenko, M. [University of Tennessee, Knoxville (UTK); Burritt (et al.), T.H. [University of Washington, Ctr Expt Nucle Phys & Astrophys; Burritt (et al.), T.H. [University of Washington, Dept Phys, Seattle, WA; Busch, M. [Duke University; Esterline, J. [Duke University; Swift, G. [Duke University; Tornow, W. [Duke University/TUNL; Ejiri, H. [Osaka University; Hazama, R. [Osaka University; Nomachi, M. [Osaka University; Shima, T. [Osaka University; Finnerty (et al.), P. [University of North Carolina; et al.
On generation of Alfvenic-like fluctuations by drift wave-zonal flow system in large plasma device experiments
According to recent experiments, magnetically confined fusion plasmas with ''drift wave-zonal flow turbulence'' (DW-ZF) give rise to broadband electromagnetic waves. Sharapov et al. [Europhysics Conference Abstracts, 35th EPS Conference on Plasma Physics, Hersonissos, 2008, edited by P. Lalousis and S. Moustaizis (European Physical Society, Switzerland, 2008), Vol. 32D, p. 4.071] reported an abrupt change in the magnetic turbulence during L-H transitions in Joint European Torus [P. H. Rebut and B. E. Keen, Fusion Technol. 11, 13 (1987)] plasmas. A broad spectrum of Alfvenic-like (electromagnetic) fluctuations appears from ExB flow driven turbulence in experiments on the large plasma device (LAPD) [W. Gekelman et al., Rev. Sci. Instrum. 62, 2875 (1991)] facility at UCLA. Evidence of the existence of magnetic fluctuations in the shear flow region in the experiments is shown. We present one possible theoretical explanation of the generation of electromagnetic fluctuations in DW-ZF systems for an example of LAPD experiments. The method used is based on generalizing results on shear flow phenomena from the hydrodynamics community. In the 1990s, it was realized that fluctuation modes of spectrally stable nonuniform (sheared) flows are non-normal. That is, the linear operators of the flows modal analysis are non-normal and the corresponding eigenmodes are not orthogonal. The non-normality results in linear transient growth with bursts of the perturbations and the mode coupling, which causes the generation of electromagnetic waves from the drift wave-shear flow system. We consider shear flow that mimics tokamak zonal flow. We show that the transient growth substantially exceeds the growth of the classical dissipative trapped-particle instability of the system.
Horton, W.; Correa, C. [Institute for Fusion Studies, The University of Texas at Austin, Austin, Texas 78712 (United States); Chagelishvili, G. D.; Avsarkisov, V. S.; Lominadze, J. G. [Georgian National Astrophysical Observatory, The Chavchavadze State University, Tbilisi 0160, Georgia and M. Nodia Institute of Geophysics, Tbilisi 0193, Georgia (United States); Perez, J. C.; Kim, J.-H. [Department of Physics, University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States); Carter, T. A. [Department of Physics, University of California, Los Angeles, California 90095 (United States)
Magical experiences in interaction design
This paper is a description of design experiments performed to investigate the use of magical experiences in interaction design of consumer electronics. Magical experiences are usually associated with a passive audience watching a magician, but it is ...
Sam de Jongh Hepworth
Human Radiation Experiments: What's New
of Defense Report Finding Aids Department of Defense Report on Search for Human Radiation Experiments Records 1944-1994 Exit Human Radiation Experiments Site This...
ORISE: Faculty Research Experiences
Faculty Research Experiences Faculty Research Experiences The Oak Ridge Institute for Science and Education (ORISE) provides short- and long-term programs for either faculty or faculty-student teams to collaborate with ORISE's science and engineering partners. The length of the faculty programs can vary-from summer internships to year-long sabbaticals-but all programs enable faculty members to broaden their professional outlook beyond the classroom to the application of laboratory research. For example, these researchers have taken advantage of ORISE opportunities: Dr. Miguel Castro Dr. Miguel Castro Dr. Miguel Castro, of the University of Puerto Rico in Mayaguez, spent three months conducting research on surface tension in Oak Ridge National Laboratory's Faculty Student Team Research program.
Electronics for Satellite Experiments
The tracking detector for the LAT science instrument on the GLAST mission is an example of a large-scale particle detection system built primarily by particle physicists for space flight within the context of a NASA program. The design and fabrication model in most ways reflected practice and experience from particle physics, but the quality assurance aspects were guided by NASA. Similarly, most of the electronics in the LAT as a whole were designed and built by staff at a particle physics lab. This paper reports on many of the challenges and lessons learned in the experience of designing and building the tracking detector and general LAT electronics for use in the NASA GLAST mission.
Johnson, Robert P.; /UC, Santa Cruz
Physics Experiments on NIF
work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344 work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344 ! LLNL Progress towards Ignition & Weapons Physics Experiments on NIF Presentation to: SEAB October 12, 2011 Ed Moses Director, NIF and Photon Science LLNL-PRES-506751 May 30, 2011 Moses_BOG_92811 NIF has broad array of technical and operational capabilities Moses_BOG_92811 Moses_BOG_92811 Laser bay NIF-0210-18489.ppt Moses presentation to Professor Mohamed Abdou, Neil Morley, Alice Ying, Robert Reed UCLA 5 Moses_All_Hands_100511 We are steadily increasing the laser energy and power available for ignition experiments: fy09 Moses_All_Hands_100511 We are steadily increasing the laser energy and power available for ignition experiments: fy10
AGS Experiments: 1989, 1990, 1991
This report contains: Experimental areas layout; table of beam parameters and fluxes; experiment schedule ``as run``; proposed 1992 schedule; a listing of experiments by number; two-page summaries of each experiment begin here, also ordered by number; publications of AGS Experiments begin here; and list of AGS Experimenters begins here.
This report contains: Experimental areas layout; table of beam parameters and fluxes; experiment schedule as run''; proposed 1992 schedule; a listing of experiments by number; two-page summaries of each experiment begin here, also ordered by number; publications of AGS Experiments begin here; and list of AGS Experimenters begins here.
APS Experiment Safety Review Board
Charter for the APS Experiment Safety Review Board May 12, 2011 1. Purpose The APS Experiment Safety Review Board (ESRB) advises the AES Division Director on the safe implementation of experiments performed by APS users on the experiment hall floor. The ESRB reviews each experiment that is submitted to the APS via the APS Experiment Safety Assessment System (ESAF). These experiments are conducted in beamline endstations in the APS Experiment Hall. 2. Membership The ESRB members are appointed by the AES Division Director. The current members of the ESRB are: Bruce Glagola AES - Chair Edmund Chang AES Paul Rossi XSD Nena Moonier AES Tom Barkalow PSC Patricia Pedergnana AES Wendy VanWingeren AES 3. Method After an experiment is submitted to the APS Experiment Safety Review system
2169 steel waveform experiments.
In support of LLNL efforts to develop multiscale models of a variety of materials, we have performed a set of eight gas gun impact experiments on 2169 steel (21% Cr, 6% Ni, 9% Mn, balance predominantly Fe). These experiments provided carefully controlled shock, reshock and release velocimetry data, with initial shock stresses ranging from 10 to 50 GPa (particle velocities from 0.25 to 1.05 km/s). Both windowed and free-surface measurements were included in this experiment set to increase the utility of the data set, as were samples ranging in thickness from 1 to 5 mm. Target physical phenomena included the elastic/plastic transition (Hugoniot elastic limit), the Hugoniot, any phase transition phenomena, and the release path (windowed and free-surface). The Hugoniot was found to be nearly linear, with no indications of the Fe-phase transition. Releases were non-hysteretic, and relatively consistent between 3- and 5-mm-thick samples (the 3 mm samples giving slightly lower wavespeeds on release). Reshock tests with explosively welded impactors produced clean results; those with glue bonds showed transient releases prior to the arrival of the reshock, reducing their usefulness for deriving strength information. The free-surface samples, which were steps on a single piece of steel, showed lower wavespeeds for thin (1 mm) samples than for thicker (2 or 4 mm) samples. A configuration used for the last three shots allows release information to be determined from these free surface samples. The sample strength appears to increase with stress from ~1 GPa to ~ 3 GPa over this range, consistent with other recent work but about 40% above the Steinberg model.
Furnish, Michael David; Alexander, C. Scott; Reinhart, William Dodd; Brown, Justin L.
Health and Safety Plan for NSTX Upgrade Project Tasks
and the DOE Hoisting and Rigging Manual. Herein is our site specific Health and Safety Plan for the work-vessel passive plates hardware. Rev 1 2 11/9111 #12;3.0 RESPONSmILITIES, AUTHORITIES, COMMUNICATIONS The Work
Edge Physics Studies on the NSTX Spherical Tokamak
In this funding period, activities were focused on processing data for publication, writing code to facilitate processing of data in the future as programmatic needs arise, and closing down grant activities.
Boedo, J
Nonthermal Electron Bernstein Emission in NSTX-Like Discharges
Technical Paper / Special Issue on Electron Cyclotron Wave Physics, Technology, and Applications - Part 2
R. W. Harvey; A. P. Smirnov; E. Nelson-Melby; G. Taylor; S. Coda; A. K. Ram
Microtearing Instabilities and Electron Transport in the NSTX Spherical Tokamak
We report a successful quantitative account of the experimentally determined electron thermal conductivity ?e in a beam-heated H mode plasma by the magnetic fluctuations from microtearing instabilities. The calculated ?e based on existing nonlinear theory agrees with the result from transport analysis of the experimental data. Without using any adjustable parameter, the good agreement spans the entire region where there is a steep electron temperature gradient to drive the instability.
K.L. Wong, S. Kaye, D.R. Mikkelsen, J.A. Krommes, K. Hill, R. Bell, and B. LeBlanc
8MAY98 8MAY98 Exp # Spokesperson Experiment Title Days 433-9 Miller Ion Irradiations of Anisotropic High-Tc Superconductors: Probing Dynamics of Magnetic Vortices 2 651-2 Paul Accelerator-Mass-Spectrometry Measurements of Natural 236U Concentrations with the ECR-ATLAS System 4 667-2 Janssens Unsafe Coulex of the 238,239Pu Nuclei 4 669-2 Carpenter Excited States Associated with Different Shapes in 178Hg and Neighboring Odd-A Nuclei 4 673-2 Lister A Study of Radiative Decay from High Lying States in 24Mg 5 689-2 Freeman Spectroscopy of Odd Tin Isotopes Approaching 100Sn 5 693-2 Reiter Structure and Formation Mechanism of Heavy Elements - Request for additional beam time for Experiment 693 - 6 706 Kwok Heavy-Ion Lithography on High Temperature Superconductors 2 708 Yu In-Beam Spectroscopy Study of the Proton Emitter 109I with Recoil-Decay Tagging Technique
Experiences Experiences w ith T ools a t N ERSC Richard G erber NERSC User Services Programming w eather, c limate, a nd e arth---system m odels on h eterogeneous m ul>---core p la?orms September 7 , 2 011 a t t he N a>onal C enter f or A tmospheric R esearch i n B oulder, C olorado 2 * Thanks f or t he i nvita>on * My p rofessional g oal i s t o e nable s cien>sts t o u se H PC easily a nd e ffec>vely * Contribute t o i mportant d iscoveries a bout h ow o ur natural w orld w orks * Make a d ifference * So i t i s a n h onor & m eaningful t o m e t o p ar>cipate i n this c onference * One o f m y p rimary r oles i s a s d eputy o n o ur n ext procurement t eam & w e a re e xtremely i nterested i n learning a bout y our e xperiences w ith h ybrid s ystems and p rogramming 3 * Recent e xperiences p roviding t ools *
Stirling machine operating experience
Numerous Stirling machines have been built and operated, but the operating experience of these machines is not well known. It is important to examine this operating experience in detail, because it largely substantiates the claim that stirling machines are capable of reliable and lengthy operating lives. The amount of data that exists is impressive, considering that many of the machines that have been built are developmental machines intended to show proof of concept, and are not expected to operate for lengthy periods of time. Some Stirling machines (typically free-piston machines) achieve long life through non-contact bearings, while other Stirling machines (typically kinematic) have achieved long operating lives through regular seal and bearing replacements. In addition to engine and system testing, life testing of critical components is also considered. The record in this paper is not complete, due to the reluctance of some organizations to release operational data and because several organizations were not contacted. The authors intend to repeat this assessment in three years, hoping for even greater participation.
Ross, B. [Stirling Technology Co., Richland, WA (United States); Dudenhoefer, J.E. [Lewis Research Center, Cleveland, OH (United States)
Recent radon transient experiments
Radon transient analysis is being developed as a method complementary to pressure transient analysis for evaluation of geothermal reservoirs. The method is based on the observations of Stoker and Kruger (1975) that radon concentration in produced geothermal fluids is related to geothermal reservoir type, production flow rates, and time. Stoker and Kruger showed that radon concentrations were markedly different in vapor-dominated and liquid-dominated systems, and varied not only among wells of different flow rate in an individual reservoir, but also varied timewise in individual wells. The potential uses of radon as an internal tracer for geothermal reservoir engineering were reviewed by Kruger, Stoker, and Umana (1977). Also included were results of the first transient test performed with rapid flow rate change in a vapor-dominated field. The results of the next four radon-flow rate transient experiments were summarized by Kruger (1978) in which effects of well interference and startup production in a new well were demonstrated. Four of these first five radon transient experiments have been carried out in vapor-dominated reservoirs at The Geysers in California and Serrazzano in Italy. The systematics of the transients of radon concentration following abrupt changes in flow rate is being evaluated by Warren and Kruger (1978). The fifth test was at the HGP-A well in Hawaii, the first transient test in a liquid-dominated reservoir. Three additional radon transient tests have been carried out, each in a different type of geothermal resource. The first test was in a petrothermal resource, the reservoir created by hydraulic fracturing by LASL in the hot, dry rock experiment in New Mexico. The results of this first 75-day production test of continuous forced circulation, during January-April, 1978, are given by Tester, et al (1978). The results of the radon concentration measurements made during this test are summarized by Kruger, Cederberg, and Semprini (1978). The second test was a second transient test at the HGP-A well in the liquid-dominated reservoir at Pohoiki, Hawaii, and the third test was a second transient test at the Grottitana well in the Serrazzano field at Larderello, Italy. The general observations of these tests are listed in Table 1. A summary of each of these three tests follows. During the LASL hot dry rock flow test, five samples of recirculating production fluid were obtained by wellhead sampling. Two samples were obtained during the following shutin and venting periods of the test, and one sample of makeup water was analyzed during the test.
Kruger, P.; Semprini, L.; Cederberg, G.; Macias, L.
Experience Report for WOPR
One of the purposes of the SQA effort at LLNL is to attempt to determine the 'goodness' of the research codes used for various scientific applications. Typically these are two and three dimensional multi-physics simulation and modeling codes. These legacy research codes are used for applciations such as atmospheric dispersion modeling and analysis and prediction of the performance of engineered systems. These codes are continually subjected to automated regression test suites consisting of verified and validated expected results. Code is managed in repositories. Experience level of developers is high in the knowledge domain, platforms, and languages used. Code size of the multi-physics code used in this study was 578,242 lines excluding comment and blank lines or 5538.7 function points. Languages were 70% C++, 20% C, and 10% Fortran. The code has 130 users and a development team of 14 and an embedded SQE. The code has achieved 100% prime feature test coverage, 73.6% functional test coverage, and 71.5% statement test coverage. The average cyclomatic complexity of the code was 6.25. The codes have evolved over 10 years. Research codes are challenging because there is a desire to balance agility with discipline as well as compliance with DOE standards. Agility is important to allow experimentation with new algorithms and addition of the latest physics features. Discipline is important to increase the quality of the codes. Automation of processes and defect prevention/detection are deployed throughout the software development process. Since resarch codes are a small segment of the software industry, not much information exists in terms of reliability studies on these types of codes. This paper describes attempts to determine the goodness of these research codes. Goodness defined as both correctness of the codes and their fault densities. Correctness is determined by user interviews, peer review; feature based automated testing, and coverage measurement. This paper focuses on the fault density aspect of goodness and reliability of the codes in particular. The approach taken was to use multiple fault density prediction methods and compare results to actual experimentation and other industry studies on fault density. As a result of the predictions and experiments our confidence in the prediction methods was increased and our confidence in the goodness of the code from a fault density perspective was given more context. A large unintended benefit of these experiments was to find defects hidden for years in the codes when using the Monte Carlo reliability testing results to develop heuristic based bug driven tests.
Pope, G
Research Experience Bibliography
Research Programs Research Programs Found in Profiling Teacher Research Participation Programs: An Approach to Formative Evaluation, The National Center for Improving Science Edcuation of the NETWORK, Inc. with support from the United States Department of Energy, November, 1993. Gottfried, S.: Brown, C.; Markovits, P.; and Changar, J. Undated. "Scientific Work Experience Programs for Science Teachers: A Focus on Research-Related Internships." Unpublished Manuscript. The authors found five factors related to effective implementation of a research internship program: (1) mentors, project staff, and teachers share goals and expectations, have open, frequent communication; (2) teachers have articulated project or research assignment; (3) curriculum development component facilitated by expert, focus on process rather than product; (4)
The German Front Experiment 1987
The German Front Experiment, 1987 (GFE87) is a field experiment using aircraft, radar, surface, and upper-air observations to determine the influence of the European Alps on cold fronts. Measurements are concentrated in the Rhine Valley and in ...
Klaus P. Hoinka; Hans Volkert
Assessment of Project Management Experience
Assessment of Project Management Experience PMCDP for CEG Competency 1.12.2 Assessment of Project Management Experience PMCDP for CEG Competency 1.12.2 Applicant Name: Applicant Supervisor: Date (mm/dd/yyyy): Directions: Step 1: Use this template to show project management experience for CEG competency 1.12.2. Rate your experience (0 - 5) in the following project management related activities using the scale below. Step 2: Sign the completed form and have your supervisor review and sign it. Step 3: Once approved by your supervisor, submit the form as part of your Level I certification package. Note: Project management experience is distinguished from FPD experience and applies to general project management activities and experience. Positions that do not count towards experience in project management include: program manager, property manager, health, safety and security (HSS) positions, and
Optimal designs for conjoint experiments
In conjoint experiments, each respondent receives a set of profiles to rate. Sometimes, the profiles are expensive prototypes that respondents have to test before rating them. Designing these experiments involves determining how many and which profiles ... Keywords: Conjoint experiments, D-optimality, Optimal block design, Optimal block sizes, Prototype testing
Roselinde Kessels; Peter Goos; Martina Vandebroek
Operating experience at CEBAF
CEBAF, the Continuous Electron Beam Accelerator Facility, is a 5-pass, recirculating, superconducting rf linac designed to provide exceptional beam quality at 4 GeV up to 200 {mu}A CW. It is made up of an injector, two 400-MeV linacs, and 9 recirculation arcs having a total beamline length of more than 4.5 km. On Nov. 5, 1995, CEBAF delivered a 4 GeV, 25-{mu}A CW electron beam to the first of 3 experimental halls and the experimental physics program was started 10 days later. Accelerator availability during the first month of the experimental run exceeded 75%. Beam properties measured in the experimental hall to date are a one sigma momentum spread of 5{times}10{sup -5} and an rms emittance of 0.2 nanometer-radians, better than design specification. CW beam has been provided from all 5 passes at 800 MeV intervals. Outstanding performance of the superconducting linacs suggests a machine energy upgrade to 6 GeV in the near term with eventual machine operation at 8-10 GeV. Results from commissioning and operations experience since the last conference are presented.
Legg, R.
Nuclear Reactor Severe Accident Experiments
Nuclear Reactor Severe Accident Experiments Nuclear Reactor Severe Accident Experiments Capabilities Engineering Experimentation Reactor Safety Testing and Analysis Overview Nuclear Reactor Severe Accident Experiments MAX NSTF SNAKE Aerosol Experiments System Components Laser Applications Robots Applications Other Facilities Other Capabilities Work with Argonne Contact us For Employees Site Map Help Join us on Facebook Follow us on Twitter NE on Flickr Nuclear Reactor Severe Accident Experiments 1 2 3 4 5 6 7 We perform experiments simulating reactor core melt phenomena in which molten core debris ("corium") erodes the concrete floor of a containment building. This occurred during the Fukushima nuclear power plant accident though the extent of concrete damage is yet unknown. This video shows the top view of a churning molten pool of uranium oxide at 2000°C (3600°F) seen during an experiment at Argonne. Corium behaves much like lava.
Experiment Hazard Class 11 - Hydrogen
1 - Hydrogen 1 - Hydrogen Applicability This hazard classification applies to all experiments and processes involving the use of gaseous hydrogen. This class includes work performed in the Experiment Hall Beamline Stations and any preparatory/setup/testing work performed in the LOM laboratories. Other hazard controls such as fire protection and life safety regulations may apply to experiments of this hazard class. A summary of controls for hydrogen use is available in the hydrogen summary document. Experiment Category Experiments involving previously reviewed hazard controls qualify for categorized as medium risk. Experiments involving new equipment or modified hazard control schemes are categorized as high risk. Experiment Hazard Control Verification Statements Engineered Controls - Applicable controls for storage and use of
GNF2 Operating Experience
GNF's latest generation fuel product, GNF2, is designed to deliver improved nuclear efficiency, higher bundle and cycle energy capability, and more operational flexibility. But along with high performance, our customers face a growing need for absolute fuel reliability. This is driven by a general sense in the industry that LWR fuel reliability has plateaued. Too many plants are operating with fuel leakers, and the impact on plant operations and operator focus is unacceptable. The industry has responded by implementing an INPO-coordinated program aimed at achieving leaker-free reliability by 2010. One focus area of the program is the relationship between fuel performance (i.e., duty) and reliability. The industry recognizes that the right balance between performance and problem-free fuel reliability is critical. In the development of GNF2, GNF understood the requirement for a balanced solution and utilized a product development and introduction strategy that specifically addressed reliability: evolutionary design features supported by an extensive experience base; thoroughly tested components; and defense-in-depth mitigation of all identified failure mechanisms. The final proof test that the balance has been achieved is the application of the design, initially through lead use assemblies (LUAs), in a variety of plants that reflect the diversity of the BWR fleet. Regular detailed surveillance of these bundles provides the verification that the proper balance between performance and reliability has been achieved. GNF currently has GNF2 lead use assemblies operating in five plants. Included are plants that have implemented extended power up-rates, plants on one and two-year operating cycles, and plants with and without NobleChem{sup TM} and zinc injection. The leading plant has undergone three pool-side inspections outages to date. This paper reviews the actions taken to insure GNF2's reliability, and the lead use assembly surveillance data accumulated to date to validate the adequacy/expected behavior of the design. (authors)
Schardt, John [GE Energy, Nuclear, 3901 Castle Hayne Road, Wilmington, NC 28402 (United States)
Tracking in Antiproton Annihilation Experiments
A major ingredient of the planned new accelerator complex FAIR, to be constructed at the GSI, Darmstadt, Germany, is the availability of antiproton beams with high quality and intensity. Among the experiments which will make use of this opportunity is PANDA, a dedicated experiment to study antiproton annihilations on nucleons and nuclei. This article gives an overview on the foreseen techniques to perform charged particle tracking in the high rate environment of this experiment.
O. N. Hartmann
The PICASSO Dark Matter Experiment
The PICASSO experiment searches for cold dark matter through the direct detection of weakly interacting massive particles (WIMPs) via their spin?dependent interactions with fluorine at SNOLAB
Ubi Wichoski; The PICASSO Collaboration
Experiment Hazard Class 9 - Magnets
hazard classification applies to all experiments involving magnets, magnetic fields, and electric fields. Other hazard classifications such as electrical safety and their...
Window Functions for CMB Experiments
We discuss the applicability and derivation of window functions for cosmic microwave background experiments on large and intermediate angular scales. These window functions describe the response of the experiment to power in a particular mode of the fluctuation spectrum. We give general formulae, illustrated with specific examples, for the most common observing strategies.
Martin White; Mark Srednicki
Abstract: Experiment Design for Scientists and Engineers
Education and Training: Experiment Design for Engineers and ... Experiment design is a systematic, rigorous, data-based approach to scientific ...
CIIR Experiments for TREC Legal 2007
... Four baseline experiments using standard In- dri retrieval facilities and simple query formula- tion techniques and two experiments using more ...
Disposition Schedule: Human Radiation Experiments | Department...
Schedule: Human Radiation Experiments Disposition Schedule: Human Radiation Experiments This database contains information on records collections related to human radiation...
LANL | Physics | Dynamic Plutonium Experiments
Dynamic plutonium experiments Dynamic plutonium experiments Since the end of nuclear testing the nation has had to rely on sophisticated computer models to ensure the safety and reliability of the nuclear weapons stockpile. This program is known as science-based stockpile stewardship. Despite possessing the world's fastest computers and most advanced modeling capability, the behavior of materials under dynamic loads that occur in a nuclear weapon are difficult to accurately model. The Dynamic Plutonium experimental program carries out experiments at the Nevada National Security Site on plutonium driven by high explosives. These experiments are needed to measure and understand the behavior of plutonium under extreme conditions. Physics Division has unique capabilities in high-speed x-ray imaging and velocimetry (measuring the
The FIFE Data Publication Experiment
The First ISLSCP Field Experiment (FIFE) provided an opportunity to test the concept of data publication for long-term access to valuable scientific data. In analogy with the procedures used in research publication, the FIFE Information System ...
Donald E. Strebel; David R. Landis; K. Fred Huemmrich; Jeffrey A. Newcomer; Blanche W. Meeson
Computer Experiments in Finite Algebra
The experiments described here concern an initial design for a computer system specifically for the handling of finite groups, rings, fields, semigroups, and vector spaces. The usefulness of such a system was discussed in ...
Maurer, W.D.
Progress in Compact Toroid Experiments
The term "compact toroids" as used here means spherical tokamaks, spheromaks, and field reversed configurations, but not reversed field pinches. There are about 17 compact toroid experiments under construction or operating, with approximate parameters listed in Table 1.
Dolan, Thomas James
San Antonio Mountain Experiment (SAMEX)
The San Antonio Mountain Experiment (SAMEX) involves a 3325 m. conically shaped, isolated mountain in north-central New Mexico where hourly observations of temperature, relative humidity, wind speed, wind direction, and precipitation are being ...
Morris H. McCutchan; Douglas G. Fox; R. William Furman
Crucial Experiments in Climate Science
This article discusses the interplay between computational experiments and scientific advancement in dynamical meteorology and climate dynamics. In doing so, the emphasis is on the dual role of computations in prediction and experimentation, ...
A. Navarra; J. L. Kinter III; J. Tribbia
Maintenance FUSION IGNITION RESEARCH EXPERIMENT
to refine the system details, interfaces and the requirements for remote handling. Table 1. FIRE RadialInsulation Enclosure Remote Maintenance Module FUSION IGNITION RESEARCH EXPERIMENT SYSTEM objectives and subsystem requirements in an arrangement that allows remote maintenance of in
Essays in macroeconomics and experiments
This dissertation consists of four chapters on empirical and experimental macroeconomics and other experimental topics. Chapter 1 uses a laboratory experiment to test the predictions of a dynamic global game designed to ...
Shurchkov, Olga
Tokamak Fusion Test Reactor experiment
A brief review of the TFTR is given in terms of the physical size of the experiment in relation to existing and future tokamaks. Some break-even criteria are mentioned. (MOW)
Furth, H.P.
Manhattan Project: Fast Neutron Experiment
Office of Scientific and Technical Information (OSTI)
An experiment to determine the cross section of uranium-235 for fast neutrons. The target is the small pile of cubes of uranium hydride. The uranium target is surrounded by larger...
Experiments on Cryogenic Complex Plasma
Experiments on a cryogenic complex plasma have been performed. Preliminary experiments include production of a plasma in a liquid helium or in a cryogenic helium gas by a pulsed discharge. The extended production of a plasma has been realized in a vapor of liquid helium or in a cryogenic helium gas by rf discharge. The charge of dust particles injected in such a plasma has been studied in detail.
Ishihara, O.; Sekine, W.; Kubota, J.; Uotani, N.; Chikasue, M.; Shindo, M. [Faculty of Engineering, Yokohama National University Yokohama, 240-8501 (Japan)
Retail Choice Experiments: Comparing Early-AdopterExperience
This paper reviews the experience with retail choice of non-residential electricity customers during the period from early 1998 through the first few months of 2000. Key findings include: (1) customers in California received a significantly smaller discount from utility tariffs than customers in other competitive markets; (2) this sample of large commercial/industrial customers believed they were benefiting significantly more from commodity savings from contracts with retail electricity service providers (RESP) than from value-added services; and,(3) market rules appear to be critical to customer experiences with retail competition, yet the relationship between market rules and market development is inadequately understood.
Golove, William
Optimizing New Dark Energy Experiments
Next generation �Stage IV� dark energy experiments under design during this grant, and now under construction, will enable the determination of the properties of dark energy and dark matter to unprecedented precision using multiple complementary probes. The most pressing challenge in these experiments is the characterization and understanding of the systematic errors present within any given experimental configuration and the resulting impact on the accuracy of our constraints on dark energy physics. The DETF and the P5 panel in their reports recommended �Expanded support for ancillary measurements required for the long-term program and for projects that will improve our understanding and reduction of the dominant systematic measurement errors.� Looking forward to the next generation Stage IV experiments we have developed a program to address the most important potential systematic errors within these experiments. Using data from current facilities it has been feasible and timely to undertake a detailed investigation of the systematic errors. In this DOE grant we studied of the source and impact of the dominant systematic effects in dark energy measurements, and developed new analysis tools and techniques to minimize their impact. Progress under this grant is briefly reviewed in this technical report. This work was a necessary precursor to the coming generations of wide-deep probes of the nature of dark energy and dark matter. The research has already had an impact on improving the efficiencies of all Stage III and IV dark energy experiments.
Tyson, J. Anthony [University of California, Davis
Mass modification experiment definition study
This report summarizes an attempt to find an experiment that would test the Haisch, Rueda, and Puthoff (HRP) conjecture that the mass and inertia of a body are induced effects brought about by changes in the quantum-fluctuation energy of the vacuum. It was not possible, however, to identify a definitive experiment. But, it was possible to identify an experiment that might be able to prove or disprove that the inertial mass of a body can be altered by making changes in the vacuum surrounding the body. Other experiments, which do not involve mass modification, but which teach something about the vacuum, were also defined and included in a ranked list of experiments. This report also contains an annotated bibliography. An interesting point raised by this paper is this: We can estimate the `vacuum energy density` to be 10{sup 108} J/cc, and the vacuum mass density to be 10{sup 94} g/cc, much higher numbers than those associated with nuclear energy. Although the field of `electromagnetic fluctuation energy of the vacuum` is admittedly an esoteric, little-understood field, it does seem to have definite potential as an energy source. 47 refs.
Forward, R.L. [Forward Unlimited, Malibu, CA (United States)
Maine Yankee Decommissioning - Experience Report: Detailed Experiences 1997-2004
Several U.S. nuclear power plants began the decommissioning process in the 1990s. Based on current information, it will be several years before the next group of plant licenses expires, and the plants begin decommissioning. This report provides detailed information on the decommissioning of one power reactor, Maine Yankee, in order to document their experience for future plants.
UNIRIB Participant Experiences: Ron Goans
Ron Goans Ron Goans Ron Goans Ron Goans Ron Goans is a graduate research assistant working on the thesis component of his master's degree in physics while performing experiments at the Holifield Radioactive Ion Beam Facility (HRIBF) at Oak Ridge National Laboratory (ORNL). His thesis research specifically relates to the field of radioactive ion beam development. The purpose of radioactive ion beam development is to study and produce high-intensity, high-purity beams of radioactive nuclides. These beams are used by nuclear physicists to study the structure of short-lived nuclei. Below is a question and answer dialog about Goans' experience in Oak Ridge. The video featured on the right side of this page also spotlights his experience with the University Radioactive Ion Beam (UNIRIB)
D and D Operational Experience
This paper describes the operational experience gained from more than 25 million man-hours of Decontamination and Decommissioning (D and D) work on both Department of Energy sites and commercial nuclear facilities in the United States. Nuclear D and D activities encompass some of the most hazardous activities imaginable - protecting workers from a huge range and endless combinations of industrial safety, radiological, nuclear safety, and industrial hygiene issues which challenges managers and safety professionals. Performing D and D activities safely is essential to project success. Managers must ensure that work is properly planned and executed, that hazards are identified and mitigated, and that operational experience is captured and utilized on future projects. Many of the lessons learned directly relate to the principles of behavioral-based safety. Our experience indicates that improved safety performance leads to improved productivity. (authors)
Meyer, K.A.; Smith, C.B. [BNG America, 9781 S. Meridian Blvd., Suite 100, Englewood, CO 80112 (United States)
Solar neutrino experiments: An update
The situation in solar neutrino physics has changed drastically in the past few years, so that now there are four neutrino experiments in operation, using different methods to look at different regions of the solar neutrino energy spectrum. These experiments are the radiochemical {sup 37}Cl Homestake detector, the realtime Kamiokande detector, and the different forms of radiochemical {sup 71}Ga detectors used in the GALLEX and SAGE projects. It is noteworthy that all of these experiments report a deficit of observed neutrinos relative to the predictions of standard solar models (although in the case of the gallium detectors, the statistical errors are still relatively large). This paper reviews the basic principles of operation of these neutrino detectors, reports their latest results and discusses some theoretical interpretations. The progress of three realtime neutrino detectors that are currently under construction, SuperKamiok, SNO and Borexino, is also discussed.
Hahn, R.L.
Major Milestone: PPPL completes first quadrant of the heart of...
Major Milestone: PPPL completes first quadrant of the heart of the National Spherical Torus Experiment Upgrade By John Greenwald March 18, 2013 Tweet Widget Facebook Like Google...
The Lead Radius Experiment PREX
The proposed PREX experiment at Jefferson Lab will measure the parity-violating electroweak asymmetry in the elastic scattering of polarized electrons at an energy of 850 MeV and a scattering angle of 6 degrees. Since the Z0 boson couples mainly to neutrons, this asymmetry provides a clean measurement of R{sub n} with a projected experimental precision of 1 %. In addition to being a fundamental test of nuclear theory, a precise measurement of R{sub n} pins down the density dependence of the symmetry energy of neutron rich nuclear matter which has impacts on neutron star structure, heavy ion collisions, and atomic parity violation experiments.
Robert Michaels
A Home Experiment in Elasticity
We analyze a simple problem in elasticity: the \\emph{initial} motion of an elastic bar that after being hanged from an end is suddenly released. In a second problem a point mass is attached on the top of the bar. The analytical solutions uncover some unexpected properties, which can be checked, with a digital camera or camcorder, in an alternative setup in which a spring is substituted for the bar. The theoretical model and the experiments are useful to understand the similarities and differences between the elastic properties of bar and spring. Students can take advantage of the home experiments to improve their understanding of elastic waves.
J. M. Aguirregabiria; A. Hern�ndez; M. Rivas
Industrial experience with design patterns
A design pattern is a particular prose form of recording design information such that designs which have worked well in the past can be applied again in similar situations in the future. The availability of a collection of design patterns can help both ... Keywords: best practices, design information recording, design patterns, design reuse, industrial experience, information sharing, software architecture documentation, software reusability, system documentation
Kent Beck; Ron Crocker; Gerard Meszaros; John Vlissides; James O. Coplien; Lutz Dominick; Frances Paulisch
Status of the MEG Experiment
The MEG experiment which searches for ?? e ? decays at the sensitivity level of 10 ?13 is now in its final stage of the preparation. Some data run is expected by the end of the year 2007. The statuses of each detector components are described.
Aki Maki; MEG Group
Connecticut Yankee Decommissioning Experience Report
Several U.S. nuclear power plants entered decommissioning in the 1990's. Based on current information, the next group of plants whose license will expire will not begin decommissioning for nearly a decade. This report provides detailed information on the decommissioning of one power reactor - Connecticut Yankee, in order to provide their experience for future plants.
The MAXIMA and MAXIPOL experiments
MAXIMA is a balloon-based bolometric experiment to measure the temperature anisotropy of the CMB over spatial frequency range 36?l?1235. The MAXIMA-1 flight produced a 124 square degree temperature anisotropy map with a beam diameter of 10 arcmin. These data have been used to produce a power spectrum which is in excellent agreement with data from BOOMERANG and DASI
P. L. Richards; M. Abroe; P. Ade; A. Balbi; J. Bock; J. Borrill; A. Boscaleri; J. Collins; P. G. Ferreira; S. Hanany; V. V. Hristov; A. H. Jaffe; B. Johnson; A. T. Lee; T. Matsumu; P. D. Mauskopf; C. B. Netterfield; E. Pascale; B. Rabii; G. F. Smoot; R. Stompor; C. D. Winant; J. H. P. Wu
Experiment 7: Heat Phase Changes
Experiment 7: Heat Phase Changes Matter has 4 phases or states: solid, liquid, gas, and plasma. This lab looks at the phase transitions from solid to liquid to gas. 1. Obtain the following materials: 600mL beaker of ice, thermometer, hot plate, timer. 2. Add a very small amount of water to the ice so
Peterson, Blake R.
Economics of quality of experience
While the recent strong increase of interest in Quality of Experience both in industry and academia has managed to place the end user again into the center of service quality evaluation, corresponding economic implications have not received similar attention ... Keywords: WQL hypothesis, Weber-Fechner law, charging for QoE, telecommunication ecosystem, utility function
Peter Reichl; Bruno Tuffin; Patrick Maill�
The Boardman Regional Flux Experiment
A field campaign was carried out near Boardman, Oregon, to study the effects of subgrid-scale variability of sensible-and latent-heat fluxes on surface boundary-layer properties. The experiment involved three U.S. Department of Energy ...
J. C. Doran; J. M. Hubbe; R. R. Kirkham; W. J. Shaw; C. D. Whiteman; F. J. Barnes; D. Cooper; W. Porch; R. L. Coutler; D. R. Cook; R. L. Hart; W. Gao; T. J. Martin; J. D. Shannon; T. L. Crawford; D. D. Baldocchi; R. J. Dobosy; T. P. Meyers; L. Balick; W. A. Dugas; R. Hicks; L. Fritschen; L. Hipps; E. Swiatek; K. E. Kunkel
The New Zealand Southern Alps Experiment
The Southern Alps Experiment is being mounted to study the influence of New Zealand's Southern Alps on local weather and climate. This paper describes these alpine influences and outlines proposed field and modeling experiments. Experiment goals ...
D. S. Wratt; R. N. Ridley; M. R. Sinclair; H. Larsen; S. M. Thompson; R. Henderson; G. L. Austin; S. G. Bradley; A. Auer; A. P. Sturman; I. Owens; B. Fitzharris; B. F. Ryan; J-F. Gayet
Design and Analysis of Numerical Experiments
Calculations with numerical models are often referred to as numerical experiments, by analogy to classical laboratory experiments. Usually, many numerical experiments are carried out to determine the response of a numerical model to variations of ...
Kenneth P. Bowman; Jerome Sacks; Yue-Fang Chang
Fermilab at Work | Experiments and Projects
Working Group U.S. Long-Baseline Neutrino Experiment Study U.S. Lattice QCD Very Large Hadron Collider WFIRST Accelerator Experiments FermilabNICADD Photoinjector Laboratory...
Former Workers Medical Facilities with Experience Evaluating...
Former Workers Medical Facilities with Experience Evaluating Chronic Beryllium Disease Former Workers Medical Facilities with Experience Evaluating Chronic Beryllium Disease April...
SLAC National Accelerator Laboratory - LCLS Graphite Experiment...
LCLS Graphite Experiment Poses New Questions for Researchers By Glenn Roberts Jr. May 21, 2012 In experiments at SLAC National Accelerator Laboratory, a powerful X-ray laser...
Meson Photoproduction Experiments with CLAS
A large part of the experimental program in Hall B of the Jefferson Lab is dedicated to light baryon spectroscopy. Meson photoprodcution experiments are essential part of this program. CEBAF Large Acceptance Spectrometer (CLAS) and availability of circularly and linearly polarized tagged photon beams and frozen spin polarized targets provide unique conditions for this type of experiments. This combination of experimental tools gives a remarkable opportunity to measure double polarization observables for different pseudo-scalar meson photoproduction processes. For the first time, a complete or nearly complete measurement became possible and will facilitate model independent extraction of the reaction amplitude. An overview of the experimental program and its current status together with recent results on double polarization measurements in ?{sup +} photoproduction are presented.
Eugene Pasyuk
Nuclide-migration field experiments
When considering groundwater flow and radionuclide retention in the complex flow systems that can occur in geologic formations, one has a serious problem in determining if laboratory studies are being performed under conditions appropriate to natural systems. This document is the project plan for a program designed to begin to address these problems. The project is being carried out jointly by the Los Alamos National Laboratory, Sandia National Laboratories, and Argonne National Laboratory. The work has three principal objectives: (1) to develop the experimental, instrumental, and safety techniques necessary to conduct controlled, small-scale radionuclide migration field experiments, including those involving actinides; (2) to use these techniques to define radionuclide migration through rock by performing generic, at-depth experiments under closely monitored conditions; and (3) to determine whether available lithologic, geochemical, and hydrologic properties together with existing or developing transport models are sufficient and appropriate to describe real field conditions.
Erdal, B.R.; Wolfsberg, K.; Johnstone, J.K.; Erickson, K.L.; Friedman, A.M.; Fried, S.; Hines, J.J.
Human Radiation Experiments: Related Sites
Experiment Experiment Related Sites Related Links Home Roadmap What's New Search HREX Multimedia Related Sites Federal DOE DOE Sites & National Laboratories Federal Other The following are organizations which provide related information and links to databases, electronic documents, and servers. FEDERAL - DOE U.S. Department of Energy (DOE) homepage (http://www.doe.gov/)contains information on DOE's Departmental Resources, Programs, Offices, National Labs and other DOE related topics. DOE's Environment, Safety and Health (ES&H) Technical Information Services (TIS) homepage (http://nattie.eh.doe.gov/) is a collection of information services designed to provide safety and health professionals with reliable, accurate and current information to assist them in performing their jobs.
UNIRIB Participant Experiences: Cara Jost
Cara Jost Cara Jost Cara Jost Cara Jost Cara Jost is a Ph.D. student in chemistry from the University of Mainz in Germany, and is involved with ion source development at the University Radioactive Ion Beam (UNIRIB) consortium as a research scholar. Jost and UNIRIB team members are researching new ways to develop radioactive ion beams for the Holifield Radioactive Ion Beam Facility (HRIBF) at Oak Ridge National Laboratory. Below is a question and answer dialog about Jost's experience in Oak Ridge. The video featured on the right side of this page also spotlights Jost's experience with UNIRIB. What is your research focus at UNIRIB? My focus is on chemical reactions in the transfer line of the target-ion source, which can be used to improve the purity of radioactive beams.
Reactor Internals Segmentation Experience Report
Several U.S. nuclear power plants entered decommissioning in the 1990's. Based on current information, the next group of plants will not begin this process for nearly a decade. This report provides detailed information on projects involving the segmentation of the Reactor Vessel Internal Subassemblies conducted at a number of plants undergoing decommissioning. Utilities have found this task very challenging from both a technological and radiation exposure perspective. This report documents the experience...
Design of the START experiment
The START experiment (Small Tight Aspect Ratio Tokamak) is a low-budget device under construction that is specifically intended to investigate MHD behavior at extremely tight aspect ratios (as low as R/a-1.2) as well as the effectiveness of a major radius compression technique to produce high toroidal current in such plasmas. The main components of the START assembly are described along with the mode of operation.
Smith, R.T.C. [UKAEA Fusion, Culham UK; Peng, Yueng Kay Martin [ORNL
Experience Based Seismic Equipment Qualification
This report provides guidelines that can be used to perform an experience-based seismic equipment qualification for verification of seismic adequacy of active electrical and mechanical equipment consistent with requirements of American Society of Civil Engineers (ASCE)-7. The report summarizes what requirements are sufficient to ensure that an item of equipment can perform its intended safety function after a design earthquake. The report also provides additional guidance on ensuring that an item of equi...
AMIE (ACRF MJO Investigation Experiment)
AMIE AMIE (ACRF MJO Investigation Experiment) Planning Meeting AMIE Science Steering Committee Chuck Long, Tony DelGenio, Bill Gustafson, Bob Houze, Mike Jensen, Steve Klein, Ruby Leung, Xaihong Liu, Ed Luke, Peter May, Sally McFarlane, Pat Minnis, Courtney Schumacher, Andy Vogelmann, Yi Wang, Xiaoqing Wu, Shaohong Xie Agenda * Proposal due May 1 !!!!!! * Primary purpose of this meeting is discussions and planning in support of
NREL: Technology Transfer - NREL Experiments Advance Hydrogen ...
Recent experiments by National Renewable Energy Laboratory (NREL) researcher Heli Wang, however, ...
NIST Experiments Challenge Fundamental Understanding of ...
NIST Experiments Challenge Fundamental Understanding of Electromagnetism. From NIST Tech Beat: November 27, 2012. ...
Experiences with 100Gbps Network Applications
directory structure. Di- rectories are arranged according to experiments, metadata characteristics, organization
Balman, Mehmet
AGS experiments: 1990, 1991, 1992. Ninth edition
This report contains a description of the following: AGS Experimental Area - High Energy Physics FY 1993 and Heavy Ion Physics FY 1993; Table of Beam Parameters and Fluxes; Experiment Schedule ``as run``; Proposed 1993 Schedule; A listing of experiments by number; Two-page summaries of each experiment begin here, also ordered by number; Publications of AGS Experiments; and List of AGS Experimenters.
HFIR Experiment Facilities | ORNL Neutron Sciences
Experiment Facilities Experiment Facilities HFIR Experiment Facilities Neutron Scattering Facilities Target Positions Experiment Facilities in the Beryllium Reflector Large Removable Beryllium Facilities Small Removable Beryllium Facilities Control-Rod Access Plug Facilities Small Vertical Experiment Facilities Large Vertical Experiment Facilities Hydraulic Tube Facility Peripheral Target Positions Neutron Activation Analysis (NAA) Laboratory and Pneumatic Tube Facilities Slant Engineering Facilities Gamma Irradiation Facility Quality Assurance Requirements Contact Information Neutron Scattering Facilities The fully instrumented HFIR will eventually include 15 state-of-the-art neutron scattering instruments, seven of which will be designed exclusively for cold neutron experiments, located in a guide hall south of the reactor
Deuterium Experiments in the Sustained Spheromak Physics Experiment
In this paper we report on the results of isotope exchange experiments in the Sustained Spheromak Physics Experiment (SSPX). We have compared {approx}500 deuterium discharges with similar discharges in hydrogen. Typically, we produce plasmas with peak toroidal currents in the range of 0.6 MA, electron temperatures (T{sub e}) of {approx}200 eV and energy confinement times ({tau}{sub E}) of {approx}200 {micro}s. The D{sub 2} fueled discharges show similar results to those with H{sub 2} fueling with no obvious differences in confinement time. Electron temperatures of {approx}200 eV with similar electron densities were observed. Both the deuterium and hydrogen fueled discharges have a calculated thermal conduction below {chi}{sub e}<10 m{sup 2}/s. However, the D{sub 2} fueled discharges had a modest increase in high-Z (titanium) impurity content suggesting an increase of physical sputtering. We find no significant mass scaling effects.
Wood, R; Hill, D N; Hooper, E; McLean, H; Ryutov, D; Woodruff, S
Experiments with the Dragon Machine
The basic characteristics of a self-sustaining chain reaction were demonstrated with the Chicago Pile in 1943, but it was not until early 1945 that sufficient enriched material became available to experimentally verify fast-neutron cross-sections and the kinetic characteristics of a nuclear chain reaction sustained with prompt neutrons alone. However, the demands of wartime and the rapid decline in effort following the cessation of hostilities often resulted in the failure to fully document the experiments or in the loss of documentation as personnel returned to civilian pursuits. When documented, the results were often highly classified. Even when eventually declassified, the data were often not approved for public release until years later.2 Even after declassification and approval for public release, the records are sometimes difficult to find. Through a fortuitous discovery, a set of handwritten notes by ''ORF July 1945'' entitled ''Dragon - Research with a Pulsed Fission Reactor'' was found by William L. Myers in an old storage safe at Pajarito Site of the Los Alamos National Laboratory3. Of course, ORF was identified as Otto R. Frisch. The document was attached to a page in a nondescript spiral bound notebook labeled ''494 Book'' that bore the signatures of Louis Slotin and P. Morrison. The notes also reference an ''Idea LS'' that can only be Louis Slotin. The discovery of the notes led to a search of Laboratory Archives, the negative files of the photo lab, and the Report Library for additional details of the experiments with the Dragon machine that were conducted between January and July 1945. The assembly machine and the experiments were carefully conceived and skillfully executed. The analyses--without the crutch of computers--display real insight into the characteristics of the nuclear chain reaction. The information presented here provides what is believed to be a complete collection of the original documentation of the observations made with the Dragon Machine in early 1945.
R.E. Malenfant
Commissioning of the ATLAS Experiment
The status of the commissioning of the ATLAS experiment as of May 2008 is presented. The sub-detector integration in recent milestone weeks is described. Cosmic commissioning in milestone week M6 included simultaneous data-taking and combined track analysis of the muon detector and inner detector, as well as combined analysis of muon detector and muon trigger. The calorimeters have achieved near-full operation, and are integrated with the calorimeter trigger. The high-level-trigger infrastructure is being installed and algorithms tested in technical runs.
Juergen Thomas; for the ATLAS Collaboration at CERN
Special Experiments: AES-UES
Special Experiments at the APS Special note is made of the following experimental activities. (Updated 2/19/2012 17:00) BEAMLINE DATES SPOKESPERSON COMMENTS 2BM-B rad #92404 2/24- 2/27 Patrick LaReviere U of C *Approvals pending *No special procedure, samples must be surveyed before and after experiment by APS-HP. 10ID-B #92409 2/29- 3/05 Ken Kemner ANL-203 *Approvals pending *Samples may be left unattended for up to 12 hours with beam ON when hutch door is secured with lock and chain. 10BM-B rad #92408 3/01- 3/06 Ken Kemner ANL-203 *Approvals Pending *Samples may be left unattended for up to 12 hours with beam ON when hutch door is secured with lock and chain. 1ID-B rad #91277 3/07- 3/12 Don Brown- LANL Mark Daymond Queen's University *Approvals Pending 3ID-B #92107 3/10- 3/19 Valentin Iota UNLV
Quantum bouncer: theory and experiment
The quantum bouncer (QB) concept is a known QM textbook example of confined particle, namely, a solution to the 1D Schroedinger equation for a linear potential (the so-called Airy equation). It would be a great methodological challenge to create such a QM object in laboratory. An attempt of observation of the QB ``running'' in the horizontal direction was recently made by the international team at the Laue-Langevin Institute, Grenoble. The experiment was performed with ultra-cold neutrons. In this paper, the experiment is analyzed in view of the authors' claim that ``neutron quantum states in Earth gravitational field'' are observed. The experimental apparatus is designed for measurements of horizontal flux of neutrons passing through an absorbing wave guide with a variable height of absorber. From our analysis, it follows, however, that in such a layout measured data are not sensitive to quantum probability density in the vertical direction. The overall conclusion is made that the experimental data do not contain sufficient information to justify the claim.
Anatoli Andrei Vankov
Stack Monitor Operating Experience Review
Stack monitors are used to sense radioactive particulates and gases in effluent air being vented from rooms of nuclear facilities. These monitors record the levels and types of effluents to the environment. This paper presents the results of a stack monitor operating experience review of the U.S. Department of Energy (DOE) Occurrence Reporting and Processing System (ORPS) database records from the past 18 years. Regulations regarding these monitors are briefly described. Operating experiences reported by the U.S. DOE and in engineering literature sources were reviewed to determine the strengths and weaknesses of these monitors. Electrical faults, radiation instrumentation faults, and human errors are the three leading causes of failures. A representative �all modes� failure rate is 1E-04/hr. Repair time estimates vary from an average repair time of 17.5 hours (with spare parts on hand) to 160 hours (without spare parts on hand). These data should support the use of stack monitors in any nuclear facility, including the National Ignition Facility and the international ITER project.
L. C. Cadwallader; S. A. Bruyere
The Polarized SRF Gun Experiment
RF electron guns are capable of producing electron bunches with high brightness, which outperform DC electron guns and may even be able to provide electron beams for the ILC without the need for a damping ring. However, all successful existing guns for polarized electrons are DC guns because the environment inside an RF gun is hostile to the GaAs cathode material necessary for polarization. While the typical vacuum pressure in a DC gun is better than 10{sup -11} torr the vacuum in an RF gun is in the order of 10{sup -9} torr. Experiments at BINP Novosibirsk show that this leads to strong ion back-bombardment and generation of dark currents, which destroy the GaAs cathode in a short time. The situation might be much more favorable in a (super-conducting) SRF gun. The cryogenic pumping of the gun cavity walls may make it possible to maintain a vacuum close to 10{sup -12} torr, solving the problem of ion bombardment and dark currents. Of concern would be contamination of the gun cavity by evaporating cathode material. This report describes an experiment that Brookhaven National Laboratory (BNL) in collaboration with Advanced Energy Systems (AES) is conducting to answer these questions.
Kewisch, Joerg; Ben-Zvi, Ilan; Rao, Triveni; Burrill, Andrew; Pate, David; Grover, Ranjan [Brookhaven National Laboratory, Upton, NY 11973 (United States); Todd, Rob; Bluem, Hans; Holmes, Doug; Schultheiss, Tom [Advanced Energy Systems, Medford, NY 11763 (United States)
The polarized SRF gun experiment.
Kewisch,J.; Ben-Zvi, I.; Rao, T.; Burrill, A.; Pate, D.; Grover, R.; Todd, R.; Bluem, H.; Holmes, D.; Schultheiss, T.
Idaho National Laboratory carried out air ingress experiments as part of validating computational fluid dynamics (CFD) calculations. An isothermal test loop was designed and set to understand the stratified-flow phenomenon, which is important as the initial air flow into the lower plenum of the very high temperature gas cooled reactor (VHTR) when a large break loss-of-coolant accident occurs. The unique flow characteristics were focused on the VHTR air-ingress accident, in particular, the flow visualization of the stratified flow in the inlet pipe to the vessel lower plenum of the General Atomic�s Gas Turbine-Modular Helium Reactor (GT-MHR). Brine and sucrose were used as heavy fluids, and water was used to represent a light fluid, which mimics a counter current flow due to the density difference between the stimulant fluids. The density ratios were changed between 0.87 and 0.98. This experiment clearly showed that a stratified flow between simulant fluids was established even for very small density differences. The CFD calculations were compared with experimental data. A grid sensitivity study on CFD models was also performed using the Richardson extrapolation and the grid convergence index method for the numerical accuracy of CFD calculations . As a result, the calculated current speed showed very good agreement with the experimental data, indicating that the current CFD methods are suitable for predicting density gradient stratified flow phenomena in the air-ingress accident.
Chang H Oh; Eung S Kim
The boardman regional flux experiment
A field campaign was carried out near Boardman, Oregon, to study the effects of subgrid-scale variability of sensible- and latent-heat fluxes on surface boundary-layer properties. The experiment involved three U.S. Department of Energy laboratories, one National Oceanic and Atmospheric Administration laboratory, and several universities. The experiment was conducted in a region of severe contrasts in adjacent surface types that accentuated the response of the atmosphere to variable surface forcing. Large values of sensible-heat flux and low values of latent-heat flux characterized a sagebrush steppe area; significantly smaller sensible-heat fluxes and much larger latent-heat fluxes were associated with extensive tracts of irrigated farmland to the north, east, and west of the steppe. Data were obtained from an array of surface flux stations, remote-sensing devices, an instrumented aircraft, and soil and vegetation measurements. The data will be used to address the problem of extrapolating from a limited number of local measurements to area-averaged values of fluxes suitable for use in global climate models. 16 refs., 13 figs.
Doran, J.C.; Hubbe, J.M.; Kirkham, R.R.; Shaw, W.J.; Whiteman, C.D. (Pacific Northwest Lab., Richland, WA (United States)); Barnes, F.J.; Cooper, D.; Porch, W. (Los Alamos National Lab., NM (United States)); Coulter, R.L.; Cook, D.R.
HERS experiment cause for confidence.
At last April's Affordable Comfort conference, I conducted a small HERS (home energy ratings) experiment to examine the relative variability of ratings in new and older homes. The experiment grew out of discussions with Oak Ridge National Laboratory Senior Researcher Mark Ternes and EPA Energy Specialist Mia South about how good the HERS tools currently employed in the new homes market are at identifying cost-effective conservation measures in existing homes. Older homes present challenges for raters that may not generally exist in new construction. These include the absence of blueprints, the inability to interview the builder, the difficulty of identifying the operating efficiency of installed equipment, and different envelope characteristics within the home caused by partial remodels over the years. For precisely these reasons, the need for accurate ratings of older homes is acute. The efficacy of ratings in existing homes hinges on two questions: How accurate are the ratings in existing homes? and, How much does accuracy matter to the selection of conservation measures? A small experiment was organized to test the variability of ratings. Two homes were chosen to represent the very broad spectra that raters can find in the new-construction and existing-home housing stock. The new home in Park Ridge, Illinois, is typical in size and layout of the homes being built in the suburbs around Chicago. This four-bedroom, two-story house with finished basement measures slightly more than 4,000 ft{sup 2}, including the basement. The older home is located in Elgin, Illinois, and was built before 1940, probably sometime in the '20s or '30s. This two-bedroom house has a basement in which the furnace, water heater, clothes washer, and dryer are located. The raters disagreed as to whether the basement should be considered part of the conditioned space. Excluding the basement area, the house measurement approximately 1,000 ft{sup 2}. The rating process included a site visit to measure the homes features, inspection of the blueprints for the new home (none existed for the Elgin home), and a blower door test. After the raters completed their analysis, I examined the effect that the variability of ratings for the Elgin home had on choices for energy conservation measures. Although the sample was small, the results of this experiment are valuable. They may be summarized as follows: First, the ratings that different analysts estimated varied more widely for the older home than they did for the new home. Second, for the older home, the identification of cost-effective energy conservation measures was insensitive to the variation in ratings. Clearly, these findings need to be verified in further experiments. But it is noteworthy that the separate ratings of the new home were in such good agreement, and that cost-effective efficiency recommendations can be arrived at even when divergences exist in the absolute rating value. These findings also suggest that it is appropriate to have confidence in ratings as a tool for identifying cost-effective energy measures in older housing stock.
Cavallo, J. D.; Energy Systems
ARM MJO Investigation Experiment on
5 5 ARM MJO Investigation Experiment on Gan Island (AMIE-Gan) Science Plan October 2011-March 2012 C Long Principal Investigator A Del Genio P May M Deng S McFarlane X Fu P Minnis W Gustafson C Schumacher R Houze A Vogelmann C Jakob Y Wang M Jensen P Webster R Johnson S Xie X Liu C Zhang E Luke April 2011 DISCLAIMER This report was prepared as an account of work sponsored by the U.S. Government. Neither the United States nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights.
AMIE (ARM MJO Investigation Experiment):
7 7 AMIE (ARM MJO Investigation Experiment): Observations of the Madden-Julian Oscillation for Modeling Studies Science Plan ARM Climate Research Facility Tropical Western Pacific Manus Site October 2011-March 2012 C Long Principal Investigator A DelGenio P May W Gustafson S McFarlane R Houze P Minnis C Jakob C Schumacher M Jensen A Vogelmann S Klein Y Wang L Ruby Leung X Wu X Liu S Xie E Luke March 2010 DISCLAIMER This report was prepared as an account of work sponsored by the U.S Government Neither the United States nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed,
Experiment Profile: Mu2e
Mu2e Mu2e NAME: Muon-to-electron conversion, or Mu2e WHAT IS THE EXPERIMENT LOOKING FOR? A muon that does not follow the traditional weak- force decay pattern into a lighter electron and two neutrinos, but converts wholly into an electron. WHAT WILL THIS TELL US ABOUT THE WORLD? * Observing Mu2e conversion would point the way to a unification of all the forces of nature controlling the interactions of matter. This unification of the four existing forces we observe today - gravity, the electromagnetic force, and the weak and strong forces - is considered Albert Einstein's dream of "grand unification. * Finding signs of this "grand unification" could explain how the universe evolved from being
Flatback airfoil wind tunnel experiment.
A computational fluid dynamics study of thick wind turbine section shapes in the test section of the UC Davis wind tunnel at a chord Reynolds number of one million is presented. The goals of this study are to validate standard wind tunnel wall corrections for high solid blockage conditions and to reaffirm the favorable effect of a blunt trailing edge or flatback on the performance characteristics of a representative thick airfoil shape prior to building the wind tunnel models and conducting the experiment. The numerical simulations prove the standard wind tunnel corrections to be largely valid for the proposed test of 40% maximum thickness to chord ratio airfoils at a solid blockage ratio of 10%. Comparison of the computed lift characteristics of a sharp trailing edge baseline airfoil and derived flatback airfoils reaffirms the earlier observed trend of reduced sensitivity to surface contamination with increasing trailing edge thickness.
Mayda, Edward A. (University of California, Davis, CA); van Dam, C.P. (University of California, Davis, CA); Chao, David D. (University of California, Davis, CA); Berg, Dale E.
Review of Solar Neutrino Experiments
This paper reviews the constraints on the solar neutrino mixing parameters with data collected by the Homestake, SAGE, GALLEX, Kamiokande, SuperKamiokande, and SNO experiments. An emphasis will be given to the global solar neutrino analyses in terms of matter-enhanced oscillation of two active flavors. The results to-date, including both solar model dependent and independent measurements, indicate that electron neutrinos are changing to other active types on route to the Earth from the Sun. The total flux of solar neutrinos is found to be in very good agreement with solar model calculations. Future measurements will focus on greater accuracy for mixing parameters and on better sensitivity to low neutrino energies.
Alain Bellerive
Fermilab SRF cryomodule operational experience
Fermi National Accelerator Laboratory is constructing an Advanced Accelerator Research and Development facility at New Muon Lab. The cryogenic infrastructure in support of the initial phase of the facility consists of two Tevatron style standalone refrigerators, cryogenic distribution system as well as an ambient temperature pumping system to achieve 2K operations with supporting purification systems. During this phase of the project a single Type III plus 1.3 GHz cryomodule was installed, cooled and tested. Design constraints of the cryomodule required that the cryomodule individual circuits be cooled at predetermined rates. These constraints required special design solutions to achieve. This paper describes the initial cooldown and operational experience of a 1.3 GHz cryomodule using the New Muon Lab cryogenic system.
Martinez, A.; Klebaner, A.L.; Theilacker, J.C.; DeGraff, B.D.; White, M.; Johnson, G.S.; /Fermilab
Spherical Torus (Spherical Tokamak) on the Path to Fusion Energy
USBPO-ITPA activities in preparation for burning plasma research in ITER using physics breadth provided and benefits from USBPO-ITPA in preparing for burning plasma research on ITER "Locked mode" threshold n
Dealiasing of Doppler Radar Velocities Using a Torus Mapping
A novel dealiasing algorithm for Doppler radar velocity data has been developed at the Swedish Meteorological and Hydrological Institute (SMHI). Unlike most other methods, it does not need independent wind information from other instruments (e.g.,...
G�nther Haase; Tomas Landelius
Quantum Unique Ergodicity for maps on the torus
When a map is classically uniquely ergodic, it is expected that its quantization will posses quantum unique ergodicity. In this paper we give examples of Quantum Unique Ergodicity for the perturbed Kronecker map, and an upper bound for the rate of convergence.
Lior Rosenzweig
espèces et la sélection naturelleo De là, il en- trona sa correspondance avec DARïdIN 0 On trouvera d
Sprott, Julien Clinton
Monsoon Trough Boundary Layer Experiment (MONTBLEX)
The Monsoon Trough Boundary Layer Experiment (MONTBLEX) is a multi-institutional, all-India coordinated program to study the atmospheric boundary-layer processes in the monsoon trough (MT) area of northern India. The experiment is being organized ...
Malti Goel; H. N. Srivastava
The BMRC Australian Monsoon Experiment: AMEX
The Bureau of Meteorology Research Centre (BMRC) willbe conducting a major research effort in the Australian tropics during 1986-1988 including a two-phase field experiment, the Australian Monsoon Experiment (AMEX). This will be done in ...
Greg J. Holland; John L. McBride; Roger K. Smith; David Jasper; Thomas D. Keenan
Experiments Concerning Variability among Subjective Analyses
The variability of subjective (hand) analyses is explored by examining the results of two synoptic laboratory experiments. Two groups of analysts participated in the first experiment, one consisting of 13 senior meteorology students (1977), the ...
Dayton G. Vincent; Herbert Borenstein
The Monterey Area Ship Track Experiment
In June 1994 the Monterey Area Ship Track (MAST) experiment was conducted off the coast of California to investigate the processes behind anthropogenic modification of cloud albedo. The motivation for the MAST experiment is described here, as ...
Philip A. Durkee; Kevin J. Noone; Robert T. Bluth
Experiment Hall & Beamline | Advanced Photon Source
Experiment Hall & Beamlines The ratchet-shaped radiation-shielding wall between the APS storage ring and the experiment hall serves as a line of demarcation. Thirty-five "sectors"...
The Lidars in Flat Terrain (LIFT) Experiment
The authors describe and present early results from the July_August 1996 Lidars in Flat Terrain (LIFT) experiment. LIFT was a boundary layer experiment that made use of recently developed Doppler, aerosol backscatter, and ozone lidars, along with ...
Stephen A. Cohn; Shane D. Mayor; Christian J. Grund; Tammy M. Weckwerth; Christoph Senff
Experience with Commissioning New Generation Gas Suspension ...
About this Abstract. Meeting, 2013 TMS Annual Meeting & Exhibition. Symposium , Alumina and Bauxite. Presentation Title, Experience with Commissioning�...
Preparations for Muon Experiments at Fermilab
The use of existing Fermilab facilities to provide beams for two muon experiments--the Muon to Electron Conversion Experiment (Mu2e) and the New g-2 Experiment--is under consideration. Plans are being pursued to perform these experiments following the completion of the Tevatron Collider Run II, utilizing the beam lines and storage rings used today for antiproton accumulation without considerable reconfiguration.
Syphers, M.J.; Popovic, M.; Prebys, E.; /Fermilab; Ankenbrandt, C.; /Muons Inc., Batavia
The 1981 ocean tomography experiment: Preliminary results
Preliminary results from a 1981 test ocean acoustic tomography experiment are presented. The system deployed in the southern North Atlantic
The Ocean Tomography Group; R. C. Spindel
Current experiments in elementary particle physics. Revision
This report contains summaries of 568 current and recent experiments in elementary particle physics. Experiments that finished taking data before 1988 are excluded. Included are experiments at BEPC (Beijing), BNL, CEBAF, CERN, CESR, DESY, FNAL, INS (Tokyo), ITEP (Moscow), IUCF (Bloomington), KEK, LAMPF, Novosibirsk, PNPI (St. Petersburg), PSI, Saclay, Serpukhov, SLAC, and TRIUMF, and also several underground and underwater experiments. Instructions are given for remote searching of the computer database (maintained under the SLAC/SPIRES system) that contains the summaries.
Galic, H. [Stanford Linear Accelerator Center, Menlo Park, CA (United States); Armstrong, F.E. [Lawrence Berkeley Lab., CA (United States); von Przewoski, B. [Indiana Univ. Cyclotron Facility, Bloomington, IN (United States)] [and others
Institute of Computer Science Computational experience with ...
Institute of Computer Science. Academy of Sciences of the Czech Republic. Computational experience with modified. conjugate gradient methods for.
Experiments with Wind to Produce Energy
Nat EXPERIMENTS WITH WIND TO PRODUCE ENERGY Curriculum: Wind Power (simple machines, weatherclimatology, aerodynamics, leverage, mechanics, atmospheric pressure, and energy...
Neutrino properties from reactor and accelerator experiments
In this talk, I discuss the general theory of neutrino oscillation experiments, putting special emphasis on the momentum distribution of the incoming neutrino beam. Then I discuss recent neutrino oscillation experiments, viz., LSND, KARMEN and CHOOZ. Experiments foreseeable in the near future have also been discussed at the end.
Pal, P B
Toward an experiment engine for lightweight grids
This paper presents a case study conducted on the Grid'5000 platform, a lightweight grid. The goal was to make a rather simple experiment, and study how difficult it was to carry out correctly. This means it had to be correct, reproducible and efficient. ... Keywords: experiment framework, experiment methodology, lightweight grid, performance study
Brice Videau; Corinne Touati; Olivier Richard
PXIE: Project X Injector Experiment
A multi-MW proton facility, Project X, has been proposed and is currently under development at Fermilab. We are planning a program of research and development aimed at integrated systems testing of critical components comprising the front end of the Project X. This program is being undertaken as a key component of the larger Project X R&D program. The successful completion of this program will validate the concept for the Project X front end, thereby minimizing a primary technical risk element within Project X. Integrated systems testing, known as the Project X Injector Experiment (PXIE), will be accomplished with a new test facility under construction at Fermilab and will be completed over the period FY12-16. PXIE will include an H{sup -} ion source, a CW 2.1-MeV RFQ and two superconductive RF (SRF) cryomodules providing up to 25 MeV energy gain at an average beam current of 1 mA (upgradable to 2 mA). Successful systems testing will also demonstrate the viability of novel front end technologies that are expected find applications beyond Project X.
Ostroumov, P.N.; /Argonne; Holmes, S.D.; Kephart, R.D.; Kerby, J.S.; Lebedev, V.A.; Mishra, C.S.; Nagaitsev, S.; Shemyakin, A.V.; Solyak, N.; Stanek, R.P.; /Fermilab; Li, D.; /LBL, Berkeley
Yuan T. Lee's Crossed Molecular Beam Experiment
Yuan T. Lee's Crossed Molecular Beam Experiment Yuan T. Lee's Crossed Molecular Beam Experiment Home | Staff | Search | Advisory Committee | User Facilities | Laboratories | Congress | Budget Yuan T. Lee's Crossed Molecular Beam Experiment http://web.archive.org/web/20000902074635/www.er.doe.gov/production/bes/YuanLee_Exp.html (1 of 4)4/7/2006 2:46:13 PM Yuan T. Lee's Crossed Molecular Beam Experiment The above illustration was drawn by Professor Yuan T. Lee, who shared the 1986 Nobel Prize in Chemistry. It shows the design for his crossed molecular beam experiment described in the story beginning on page 27 of "Basic Energy Sciences: Summary of Accomplishments" (DOE/ER-0455P, May 1990); the story is also copied below. The purpose of this experiment was to study the chemical reaction of sodium atoms with oxygen molecules. In the experiment, a beam of sodium atoms (green,
LCLS CDR Chapter 3 - Scientific Experiments
3 3 Scientific Basis for Optical Systems TECHNICAL SYNOPSIS The LCLS Scientific Advisory Committee (SAC) has recommended experiments in five scientific disciplines for the initial operation of the LCLS. These experiments cover a variety of scientific disciplines: atomic physics, plasma physics, chemistry, biology and materials science. The x-ray optics and detectors needed to verify the LCLS capability to address these five disciplines will be constructed and installed as part of the LCLS project. The experiments are described in detail in the document "LCLS: The First Experiments" referenced earlier. Two classes of experiments are proposed for the LCLS. The first class consists of experiments where the x-ray beam is used to probe the sample, as is done in most experiments at current
Today and Future Neutrino Experiments at Krasnoyarsk Nuclear Reactor
The results of undergoing experiments and new experiment propositions at Krasnoyarsk underground nuclear reactor are presented
Yu. V. Kozlov; S. V. Khalturtsev; I. N. Machulin; A. V. Martemyanov; V. P. Martemyanov; A. A. Sabelnikov; V. G. Tarasenkov; E. V. Turbin; V. N. Vyrodov; L. A. Popeko; A. V. Cherny; G. A. Shishkina
2XIIB plasma confinement experiments
This paper reports results of 2XIIB neutral-beam injection experiments with plasma-stream stabilization. The plasma stream is provided either by a pulsed plasma generator located on the field lines outside the plasma region or by ionization of neutral gas introduced at the mirror throat. In the latter case, the gas is ionized by the normal particle flux through the magnetic mirror. A method of plasma startup and sustenance in a steady-state magnetic field is reported in which the plasma stream from the pulsed plasma generator serves as the initial target for the neutral beams. After an energetic plasma of sufficient density is established, the plasma generator stream is replaced by the gas-fed stream. Lifetimes of the stabilized plasma increase with plasma temperature in agreement with the plasma stabilization of the drift-cyclotron loss-cone mode. The following plasma parameters are attained using the pulsed plasma generator for stabilization: n approximately 5 x 10/sup 13/ cm/sup -3/, anti W/sub i/ approximately 13 keV, T/sub e/ = 140 eV, and ntau/sub p/ approximately 7 x 10/sup 10/ cm/sup -3/.s. With the gas feed, the mean deuterium ion energy is 9 keV and the peak density n approximately 10/sup 14/ cm/sup -3/. In the latter case, the energy confinement parameter reaches ntau/sub E/ = 7 x 10/sup 10/ cm/sup -3/.s, and the particle confinement parameter reaches ntau/sub p/ = 1 x 10/sup 11/ cm/sup -3/.s.
Coensgen, F.H.; Clauser, J.F.; Correll, D.L.
The BigBoss Experiment
BigBOSS is a Stage IV ground-based dark energy experiment to study baryon acoustic oscillations (BAO) and the growth of structure with a wide-area galaxy and quasar redshift survey over 14,000 square degrees. It has been conditionally accepted by NOAO in response to a call for major new instrumentation and a high-impact science program for the 4-m Mayall telescope at Kitt Peak. The BigBOSS instrument is a robotically-actuated, fiber-fed spectrograph capable of taking 5000 simultaneous spectra over a wavelength range from 340 nm to 1060 nm, with a resolution R = {lambda}/{Delta}{lambda} = 3000-4800. Using data from imaging surveys that are already underway, spectroscopic targets are selected that trace the underlying dark matter distribution. In particular, targets include luminous red galaxies (LRGs) up to z = 1.0, extending the BOSS LRG survey in both redshift and survey area. To probe the universe out to even higher redshift, BigBOSS will target bright [OII] emission line galaxies (ELGs) up to z = 1.7. In total, 20 million galaxy redshifts are obtained to measure the BAO feature, trace the matter power spectrum at smaller scales, and detect redshift space distortions. BigBOSS will provide additional constraints on early dark energy and on the curvature of the universe by measuring the Ly-alpha forest in the spectra of over 600,000 2.2 < z < 3.5 quasars. BigBOSS galaxy BAO measurements combined with an analysis of the broadband power, including the Ly-alpha forest in BigBOSS quasar spectra, achieves a FOM of 395 with Planck plus Stage III priors. This FOM is based on conservative assumptions for the analysis of broad band power (k{sub max} = 0.15), and could grow to over 600 if current work allows us to push the analysis to higher wave numbers (k{sub max} = 0.3). BigBOSS will also place constraints on theories of modified gravity and inflation, and will measure the sum of neutrino masses to 0.024 eV accuracy.
Schelgel, D.; Abdalla, F.; Abraham, T.; Ahn, C.; Allende Prieto, C.; Annis, J.; Aubourg, E.; Azzaro, M.; Bailey, S.; Baltay, C.; Baugh, C.; Bebek, C.; Becerril, S.; Blanton, M.; Bolton, A.; Bromley, B.; Cahn, R.; Carton, P.-H.; Cervanted-Cota, J.L.; Chu, Y.; Cortes, M.; /APC, Paris /Brookhaven /IRFU, Saclay /Marseille, CPPM /Marseille, CPT /Durham U. / /IEU, Seoul /Fermilab /IAA, Granada /IAC, La Laguna / /IAC, Mexico / / /Madrid, IFT /Marseille, Lab. Astrophys. / / /New York U. /Valencia U.
Current Experiments in Particle Physics (September 1996)
This report contains summaries of current and recent experiments in Particle Physics. Included are experiments at BEPC (Beijing), BNL, CEBAF, CERN, CESR, DESY, FNAL, Frascati, ITEP (Moscow), JINR (Dubna), KEK, LAMPF, Novosibirsk, PNPI (St. Petersburg), PSI, Saclay, Serpukhov, SLAC, and TRIUMF, and also several proton decay and solar neutrino experiments. Excluded are experiments that finished taking data before 1991. Instructions are given for the World Wide Web (WWW) searching of the computer database (maintained under the SLAC-SPIRES system) that contains the summaries. This report contains full summaries of 180 approved current and recent experiments in elementary particle physics. The focus of the report is on selected experiments which directly contribute to our better understanding of elementary particles and their properties such as masses, widths or lifetimes, and branching fractions.
Galic, H.; Lehar, F.; Klyukhin, V.I.; Ryabov, Yu.G.; Bilak, S.V.; Illarionova, N.S.; Khachaturov, B.A.; Strokovsky, E.A.; Hoffman, C.M.; Kettle, P.-R.; Olin, A.; Armstrong, F.E.
Software engineering: What do experiments need?
This paper will review the use of software engineering in High Energy Physics experiments and will suggest ways in which that use will change significantly in the future. In Principle, experiments do not need software engineering. We can verify this by looking at a long series of experiments that have succeeded without it. Some experiments that have tried to apply formal engineering methods have given them up before the software was complete. Future experiments, however, face many new challenges in the larger data samples, larger and more distributed collaborations and longer time scales. In addition, new tools are available to aid in the development of complex software systems. It is appropriate, therefore, to examine whether there is now a better match between software engineering and the needs of experiments.
Loken, S.C.
Software engineering: What do experiments need
The XENON100 Dark Matter Experiment
The XENON100 experiment is searching for WIMPs, which are particles that may consist dark matter. It is located in the underground laboratory of Gran Sasso (LNGS) in Italy at a depth of {approx}3600 m.w.e.. The experiment description, its performance and the expected background based on Monte Carlo simulations and material screening along with the projected sensitivities of the experiment are presented. In addition, a brief description of the upgrade XENON100 detector is given.
Tziaferi, E. [Physics Institute, University of Zuerich, Winterthurerstr. 190, Zuerich (Switzerland)
Kilauea Iki lava lake experiment plans
Twelve experimental studies are proposed to complete field laboratory work at Kilauea Iki lava lake. Of these twelve experiments, eleven do not require the presence of melt. Some studies are designed to use proven techniques in order to expand our existing knowledge, while others are designed to test new concepts. Experiments are grouped into three main categories: geophysics, energy extraction, and drilling technology. Each experiment is described in terms of its location, purpose, background, configuration, operation, and feasibility.
Dunn, J.C.; Hills, R.G.
Magnet operating experience review for fusion applications
This report presents a review of magnet operating experiences for normal-conducting and superconducting magnets from fusion, particle accelerator, medical technology, and magnetohydrodynamics research areas. Safety relevant magnet operating experiences are presented to provide feedback on field performance of existing designs and to point out the operational safety concerns. Quantitative estimates of magnet component failure rates and accident event frequencies are also presented, based on field experience and on performance of similar components in other industries.
Cadwallader, L.C.
Systematic errors in long baseline oscillation experiments
This article gives a brief overview of long baseline neutrino experiments and their goals, and then describes the different kinds of systematic errors that are encountered in these experiments. Particular attention is paid to the uncertainties that come about because of imperfect knowledge of neutrino cross sections and more generally how neutrinos interact in nuclei. Near detectors are planned for most of these experiments, and the extent to which certain uncertainties can be reduced by the presence of near detectors is also discussed.
Harris, Deborah A.; /Fermilab
WIPP Gas-Generation Experiments
An experimental investigation was conducted for gas generation in contact-handled transuranic (CH TRU) wastes subjected for several years to conditions similar to those expected to occur at the Waste Isolation Pilot Plant (WIPP) should the repository eventually become inundated with brine. Various types of actual CH TRU wastes were placed into 12 corrosion-resistant vessels. The vessels were loosely filled with the wastes, which were submerged in synthetic brine having the same chemical composition as that in the WIPP vicinity. The vessels were also inoculated with microbes found in the Salado Formation at WIPP. The vessels were sealed, purged, and the approximately 750 ml headspace in each vessel was pressurized with nitrogen gas to approximately 146 atmospheres to create anoxic conditions at the lithostatic pressure estimated in the repository were it to be inundated. The temperature was maintained at the expected 30�C. The test program objective was to measure the quantities and species of gases generated by metal corrosion, radiolysis, and microbial activity. These data will assist in the specification of the rates at which gases are produced under inundated repository conditions for use in the WIPP Performance Assessment computer models. These experiments were very carefully designed, constructed, instrumented, and performed. Approximately 6 1/2 years of continuous, undisturbed testing were accumulated. Several of the vessels showed significantly elevated levels of generated gases, virtually all of which was hydrogen. Up to 4.2% hydrogen, by volume, was measured. Only small quantities of other gases, principally carbon dioxide, were detected. Gas generation was found to depend strongly on the waste composition. The maximum hydrogen generation occurred in vessels containing carbon steel. Visual examination of carbon-steel coupons confirmed the correspondence between the extent of observable corrosion and hydrogen generation. Average corrosion penetration rates in carbon-steel of up to 2.3 microns per year were deduced. Conversion of carbon to carbon dioxide was calculated to be as high as 4.7 �g mol/yr/g carbon. Carbon monoxide was detected in only two waste compositions, and methane was detected in only one. In all three of these cases, the concentrations of these lesser gases detected were barely above the detection limits. No hydrogen sulfide was ever detected. Initial rates of hydrogen generation measured in the carbon-steel-bearing wastes during the first year of testing did not always correspond to rates measured over the longer term. Compared to the long-term trends, the initial gas-generation rates for some waste types were higher, for some lower, and for others remained constant. Although carbon-steel corrosion was clearly the dominant hydrogen generator, the rates of generation were found to be reduced in test vessels where the same quantity of carbon steel was co-mingled with other waste types. This is a beneficial phenomenon relative to performance of the WIPP repository. Statistical analyses of the results were made to quantify these negative interaction effects. Electron microscopy analyses of the carbon-steel coupons revealed that corrosion products were predominantly iron chlorides and oxides. Iron, chlorine, oxygen, uranium, magnesium, calcium, aluminum, silicon were all present in the corrosion products. No americium nor neptunium, both present in the wastes, were detected in any of the corrosion products. All
Frank S. Felicione; Steven M. Frank; Dennis D. Keiser
Roadmap to the Project: Experiments List
into the environment. These releases were designed to characterize the dispersion of radiation. The purpose of the experiment was to enable scientists to determine the fraction...
Walker Branch Throughfall Displacement Experiment Data Report...
M. E. Wolfe, and E. G. O'Neill. 2001. Walker Branch Throughfall Displacement Experiment Data Report: Site Characterization, System Performance, Weather, Species Composition, and...
Fermilab | Science at Fermilab | Experiments & Projects
main content Science at Fermilab Frontiers of Particle Physics Experiments & Projects Energy Frontier Tevatron at Fermilab Fermilab and the LHC Intensity Frontier Cosmic Frontier...
Current experiments in elementary particle physics. Revised
This report contains summaries of 584 current and recent experiments in elementary particle physics. Experiments that finished taking data before 1986 are excluded. Included are experiments at Brookhaven, CERN, CESR, DESY, Fermilab, Tokyo Institute of Nuclear Studies, Moscow Institute of Theoretical and Experimental Physics, KEK, LAMPF, Novosibirsk, Paul Scherrer Institut (PSI), Saclay, Serpukhov, SLAC, SSCL, and TRIUMF, and also several underground and underwater experiments. Instructions are given for remote searching of the computer database (maintained under the SLAC/SPIRES system) that contains the summaries.
Galic, H. [Stanford Univ., CA (United States). Stanford Linear Accelerator Center; Wohl, C.G.; Armstrong, B. [Lawrence Berkeley Lab., CA (United States); Dodder, D.C. [Los Alamos National Lab., NM (United States); Klyukhin, V.I.; Ryabov, Yu.G. [Inst. for High Energy Physics, Serpukhov (Russian Federation); Illarionova, N.S. [Inst. of Theoretical and Experimental Physics, Moscow (Russian Federation); Lehar, F. [CEN Saclay, Gif-sur-Yvette (France); Oyanagi, Y. [Univ. of Tokyo (Japan). Faculty of Sciences; Olin, A. [TRIUMF, Vancouver, BC (Canada); Frosch, R. [Paul Scherrer Inst., Villigen (Switzerland)
Fermilab | Science at Fermilab | Experiments & Projects | Intensity...
to main content Science at Fermilab Frontiers of Particle Physics Experiments & Projects Energy Frontier Tevatron at Fermilab Fermilab and the LHC Intensity Frontier Cosmic...
Incorporating Experience Curves in Appliance Standards Analysis
experience curves for wind farms. Energy Policy 33, 133-150.curves for wind power. Energy Policy 30, 1181- Jakob, M. ,
Desroches, Louis-Benoit
ORISE: Graduate Student Research Experiences - Benjamin Martin
Experiences program at Oak Ridge National Laboratory, is trying to improve emergency response by developing computer codes to fuse together two different kinds of satellite...
Current experiments in elementary particle physics
This report contains summaries of 736 current and recent experiments in elementary particle physics (experiments that finished taking data before 1982 are excluded). Included are experiments at Brookhaven, CERN, CESR, DESY, Fermilab, Tokyo Institute of Nuclear Studies, Moscow Institute of Theoretical and Experimental Physics, Joint Institute for Nuclear Research (Dubna), KEK, LAMPF, Novosibirsk, PSI/SIN, Saclay, Serpukhov, SLAC, and TRIUMF, and also several underground experiments. Also given are instructions for searching online the computer database (maintained under the SLAC/SPIRES system) that contains the summaries. Properties of the fixed-target beams at most of the laboratories are summarized.
Wohl, C.G.; Armstrong, F.E.; Trippe, T.G.; Yost, G.P. (Lawrence Berkeley Lab., CA (USA)); Oyanagi, Y. (Tsukuba Univ., Ibaraki (Japan)); Dodder, D.C. (Los Alamos National Lab., NM (USA)); Ryabov, Yu.G.; Slabospitsky, S.R. (Gosudarstvennyj Komitet po Ispol'zovaniyu Atomnoj Ehnergii SSSR, Serpukhov (USSR). Inst. Fiziki Vysokikh Ehnergij); Frosch, R. (Swiss Inst. for Nuclear Research, Villigen (Switzerla
SLAC National Accelerator Laboratory - Experiment Finds Ulcer...
10, 2012 Menlo Park, Calif. - Experiments at the U.S. Department of Energy's (DOE) SLAC National Accelerator Laboratory have revealed a potential new way to attack common...
Office of Human Radiation Experiments - Archived Website
documents cold war metabolism of lethal dose studies with rates dose experiments medical research program Iodine-131 Iron-59 For further information regarding information...
Spatial Patterns Confound Experiments in Orchard Crops
patterns differ among sites, crops, and process of interest,currently lacking in the tree crops, specifically, and thecommonly used in tree crop experiments and in fertilizer
Rosenstock, Todd S; Plant, Richard E; Brown, Patrick H
Efficient designs for constrained mixture experiments
Many practical experiments on mixtures (where the components sum to one) include additional lower or upper bounds on components, or on linear combinations of them. Usually theory cannot be used to obtain a good design, and algorithmic methods are necessary. ... Keywords: Algorithms, mixture experiments, optimal design
R. J. Martin; M. C. Bursnall; E. C. Stillman
Title of dissertation: ROTATING, HYDROMAGNETIC LABORATORY EXPERIMENT
understanding, and if I live a decade beyond that, everything I paint -- every dot and line -- will be alive. I experiments. In fact, the predominance of inertial modes in our experiments and in other recent work leads, and around the age of fifty, I began to work in earnest, producing numerous designs. It was not until after
Lathrop, Daniel P.
Yankee Rowe Decommissioning Experience Record: Volume 1
This report describes Yankee Atomic's experiences in the process of decommissioning the Yankee Rowe nuclear power plant. This volume presents lessons learned during work finished by September 1997. A second volume, to be published in 1998, will complete the experience record. The recommendations and insights in this report will be valuable to other utilities with permanently shutdown plants.
Experiences of Wiki use in Finnish companies
The objective of our study was two-fold. The first and most important objective was to gather experiences on the use of wiki software in Finnish companies. The second objective was to study the frequency of the use of wikis among Finland's 50 biggest ... Keywords: adoption, company use, motivation, user experience, wiki software
Jani Henriksson; Teemu Mikkonen; Tere Vad�n
User Experience Design Guidelines for Windows Phone
User Experience Design Guidelines for Windows Phone The UI Design and Interaction Guide for Windows superseded by the User Experience Design Guidelines for Windows Phone on MSDN ® . There are six parts to the new guidelines: 1. The Windows Phone Platform: Takes a brief look at the types of applications
Narasayya, Vivek
Ris-M-2874 Neutron Diffraction Experiments
;1. Introduction The nuclear spin systems in metals provide ideal models to test theoretical ideas by experiments Roskilde, Denmark August 1990 #12;Abstract Nuclear spins in silver constitute an ideal antiferromagnetic study the feasibility of neutron diffraction experiments on nuclear magnetic order in silver
Operating and maintenance experience in tritium environments
This presentation is a summary of practical experience gained over more than twenty years from analyzing failures of process equipment operated in tritium and deuterium environments. Significant improvements have been achieved in design and procurement of new equipment, testing and selection of materials, and gradually more favorable maintenance experience. Preferred materials and inspection methods are described. 6 tabs.
Tuer, G.L.
Preliminary results of the echo-seeding experiment at SLAC
experiment at NLCTA�, SLAC LDRD programme, �http://EEHG experiment (ECHO-7) at SLAC has gone from the designgeneration experiment at SLAC�, These proceedings, [9] J.H.
Xiang, D.
Discovering New Light States at Neutrino Experiments
Experiments designed to measure neutrino oscillations also provide major opportunities for discovering very weakly coupled states. In order to produce neutrinos, experiments such as LSND collide thousands of Coulombs of protons into fixed targets, while MINOS and MiniBooNE also focus and then dump beams of muons. The neutrino detectors beyond these beam dumps are therefore an excellent arena in which to look for long-lived pseudoscalars or for vector bosons that kinetically mix with the photon. We show that these experiments have significant sensitivity beyond previous beam dumps, and are able to partially close the gap between laboratory experiments and supernovae constraints on pseudoscalars. Future upgrades to the NuMI beamline and Project X will lead to even greater opportunities for discovery. We also discuss thin target experiments with muon beams, such as those available in COMPASS, and show that they constitute a powerful probe for leptophilic PNGBs.
Essig, Rouven; /SLAC; Harnik, Roni; /Fermilab; Kaplan, Jared; /SLAC; Toro, Natalia; /Stanford U., Phys. Dept.
Hierarchical Control of the ATLAS Experiment
Control systems at High Energy Physics (HEP) experiments are becoming increasingly complex mainly due to the size, complexity and data volume associated to the front-end instrumentation. In particular, this becomes visible for the ATLAS experiment at the LHC accelerator at CERN. ATLAS will be the largest particle detector ever built, result of an international collaboration of more than 150 institutes. The experiment is composed of 9 different specialized sub-detectors that perform different tasks and have different requirements for operation. The system in charge of the safe and coherent operation of the whole experiment is called Detector Control System (DCS). This thesis presents the integration of the ATLAS DCS into a global control tree following the natural segmentation of the experiment into sub-detectors and smaller sub-systems. The integration of the many different systems composing the DCS includes issues such as: back-end organization, process model identification, fault detection, synchronization ...
Barriuso-Poy, Alex; Llobet-Valero, E
Electrical Transport Experiments at High Pressure
High-pressure electrical measurements have a long history of use in the study of materials under ultra-high pressures. In recent years, electrical transport experiments have played a key role in the study of many interesting high pressure phenomena including pressure-induced superconductivity, insulator-to-metal transitions, and quantum critical behavior. High-pressure electrical transport experiments also play an important function in geophysics and the study of the Earth's interior. Besides electrical conductivity measurements, electrical transport experiments also encompass techniques for the study of the optoelectronic and thermoelectric properties of materials under high pressures. In addition, electrical transport techniques, i.e., the ability to extend electrically conductive wires from outside instrumentation into the high pressure sample chamber have been utilized to perform other types of experiments as well, such as high-pressure magnetic susceptibility and de Haas-van Alphen Fermi surface experiments. Finally, electrical transport techniques have also been utilized for delivering significant amounts of electrical power to high pressure samples, for the purpose of performing high-pressure and -temperature experiments. Thus, not only do high-pressure electrical transport experiments provide much interesting and valuable data on the physical properties of materials extreme compression, but the underlying high-pressure electrical transport techniques can be used in a number of ways to develop additional diagnostic techniques and to advance high pressure capabilities.
Weir, S
IEA Workshop (W60) on Burning Plasmas and Simulation Name Institute Speaker/ C Title talk
IEA Workshop (W60) on Burning Plasmas and Simulation Name Institute Speaker/ C Title talk Start End 04-Jul-05 Session 1 Transport and Confinement in Burning Plasmas 8.30 8.40 Miura Y. JAERI- Naka chair Experiments on JET 10.00 10.20 Peng M. PPPL speaker NSTX Results relevant for Burning Plasmas 10.20 10
Requirements for the GCFR plenum streaming experiment
This report gives the experiment objectives and generic descriptions of experimental configurations for the gas-cooled fast breeder reactor (GCFR) plenum shield experiment. This report defines four experiment phases. Each phase represents a distinct area of uncertainty in computing radiation transport from the GCFR core to the plenums, through the upper and lower plenum shields, and ultimately to the prestressed concrete reactor vessel (PCRV) liner: (1) the shield heterogeneity phase; (2) the exit shield simulation phase; (3) the plenum streaming phase; and (4) the plenum shield simulation phase.
Perkins, R.G.; Rouse, C.A.; Hamilton, C.J.
AGS experiments -- 1995, 1996 and 1997
This report contains (1) FY 1995 AGS schedule as run; (2) FY 1996 AGS schedule as run; (3) FY 1997 AGS schedule as run; (4) FY 1998--1999 AGS schedule (proposed); (5) AGS beams 1997; (6) AGS experimental area FY 1995 physics program; (7) AGS experimental area FY 1996 physics program; (8) AGS experimental area FY 1997 physics program; (9) AGS experimental area FY 1998--1999 physics program (proposed); (10) a listing of experiments by number; (11) two-page summaries of each experiment, in order by number; and (12) listing of publications of AGS experiments.
Depken, J.C.; Presti, P.L.
Scanning and Mapping Strategies for CMB Experiments
CMB anisotropy experiments seeking to make maps with more pixels than the 6144 pixels used by the COBE DMR need to address the practical issues of the computer time and storage required to make maps. A simple, repetitive scan pattern reduces these requirements but leaves the experiment vulnerable to systematic errors and striping in the maps. In this paper I give a time-ordered method for map-making with one-horned experiments that has reasonable memory and CPU needs but can handle complex COBE-like scans paths and 1/f noise.
Edward L. Wright
Student Career Experience Program | National Nuclear Security
National Nuclear Security Administration (NNSA)
Our Jobs > Opportunities for Students > Student Our Jobs > Opportunities for Students > Student Career Experience Program Student Career Experience Program The Student Career Experience Program (SCEP) is a great way to start your NNSA career while pursuing your studies in college or graduate school. This program gives you the opportunity to combine your academic studies with on-the-job training and experience directly related to your academic program. You will have the opportunity to work on exciting NNSA projects, earn money while serving your nation and take advantage of an excellent benefits package, all while maintaining your student status and completing your education. SCEP allows our managers to evaluate your performance in real work situations and discover first-hand your abilities as a potential
Documentation Requirements for Pressurized Experiment Equipment
Documentation Requirements for Pressurized Experiment Apparatus Documentation Requirements for Pressurized Experiment Apparatus PSSC NOTE01 15-Jan-2013 When bringing a piece of apparatus to the APS for an experiment that will involve pressure, whether it is to be used on a beamline during a measurement or in a laboratory to prepare the sample prior to the experiment, the hazards associated with the equipment must be reviewed. To review the equipment and make any recommendations, a certain level of documentation must be provided by the experimenter. The length and depth of the documentation should be commensurate with the complexity of the system. 1. Description of apparatus a. Description of the assembly and operation of the system. b. State the maximum working pressure, working fluid (liquid or gas) used to
From design experiments to formative interventions
The discussion of design experiments has largely ignored the Vygotskian tradition of formative interventions based on the principle of double stimulation. This tradition offers a radical approach to learning reasearch which focuses on the agency of the ...
Yrj� Engestr�m
Confined volume blasting experiments: Description and analysis
A series of bench-scale blasting experiments was conducted to produce rubble beds for use in retorting experiments. The experiments consisted of blasting oil shale with explosives within a confined volume containing 25% void. A variety of blasting geometries was used to control the fragment size distribution and void distribution in the rubble. The series of well controlled tests provided excellent data for use in validating rock fragmentation models. Analyses of the experiments with PRONTO, a dynamic finite element computer code, and a newly developed fracturing model provided good agreement between code predictions and experimental measurements of fracture extent and fragment size. CAROM, a dynamic distinct element code developed to model rock motion during blasting, was used to model the fully fragmented tests. Calculations of the void distribution agreed well with experimentally measured values. 9 refs., 11 figs., 1 tab.
Gorham-Bergeron, E.; Kuszmaul, J.S.; Bickel, T.C.; Shirey, D.L.
Oceanographic Experiment Design by Simulated Annealing
The oceanographic experiment design problem is discussed in the context of several simple examples drawn from acoustic tomography. The optimization of an objective function�chosen to characterize the array design� is carried out using the ...
Norman Barth; Carl Wunsch
GNSS radio occultation constellation observing system experiments
Observing system experiments within the operational ECMWF data assimilation framework have been performed for summer 2008 when the largest recorded number of GNSS radio occultation observations from both operational and experimental satellites ...
Peter Bauer; G�bor Radn�ti; Sean Healy; Carla Cardinali
State of work on the AMBAL experiment
A diagram of the AMBAL tandem mirror experiment is given. The main topics discussed are the vapor jet, titanium vaporizer, plasma gun, startup injectors, main injectors, diagnostics, and numerical modeling. (MOW)
Hamilton, G.W.
Summer Monsoon Experiment�A Review
This paper presents a short summary of the Summer Monsoon Experiment (MONEX). The review is largely based on those papers that have made use of the summer MONEX observations during 1979. 0bservational aspects of this study emphasize the annual ...
T. N. Krishnamurti
Early Experiences with the EGrid Testbed
The Testbed and Applications working group of the European Grid Forum (EGrid) is actively building and experimenting with a grid infrastructure connecting several research-based supercomputing sites located in Europe. This paper reports on our first ...
Gabrielle Allen; Thomas Dramlitsch; Tom Goodale; Gerd Lanfermann; Thomas Radke; Ed Seidel; Thilo Kielmann; Kees Verstoep; Zoltan Balaton; Peter Kacsuk; Ferenc Szalai; Joern Gehring; Axel Keller; Achim Streit; Ludek Matyska; Miroslav Ruda; Ales Krenek; Harald Knipp; Andr� Merzky; Alexander Reinefeld; Florian Schintke; Bogdan Ludwiczak; Jarek Nabrzyski; Juliusz Pukacki; Hans-Peter Kersken; Giovanni Aloisio; Massimo Cafaro; Wolfgang Ziegler; Michael Russell
The Terrain-Induced Rotor Experiment
The Terrain-Induced Rotor Experiment (T-REX) is a coordinated international project, composed of an observational field campaign and a research program, focused on the investigation of atmospheric rotors and closely related phenomena in complex ...
Vanda Grubi�i?; James D. Doyle; Joachim Kuettner; Richard Dirks; Stephen A. Cohn; Laura L. Pan; Stephen Mobbs; Ronald B. Smith; C. David Whiteman; Stanley Czyzyk; Simon Vosper; Martin Weissmann; Samuel Haimov; Stephan F. J. De Wekker; Fotini Katopodes Chow
ORISE: Recent Graduate Research Experiences - Lindsay Gabbert
by the U.S. Department of Homeland Security (DHS) and the U.S. Department of Agriculture, accepts scientists at all levels and provides them with laboratory experience and...
The Tropical Warm Pool International Cloud Experiment
A comprehensive dataset describing tropical cloud systems and their environmental setting and impacts has been collected during the Tropical Warm Pool International Cloud Experiment (TWP-ICE) and Aerosol and Chemical Transport in Tropical ...
Peter T. May; James H. Mather; Geraint Vaughan; Keith N. Bower; Christian Jakob; Greg M. McFarquhar; Gerald G. Mace
Plasma Dynamo Experiments Cary Forest PPPL Colloquium
Dynamo Experiments Cary Forest PPPL Colloquium 5 th June 2013 Wednesday, June 5, 13 So many dynamos (s men dnuh-mz), 1. a phrase which reads the same backwards and...
ATLAS distributed computing: experience and evolution
The ATLAS experiment has just concluded its first running period which commenced in 2010. After two years of remarkable performance from the LHC and ATLAS, the experiment has accumulated more than 25/fb of data. The total volume of beam and simulated data products exceeds 100~PB distributed across more than 150 computing centres around the world, managed by the experiment's distributed data management system. These sites have provided up to 150,000 computing cores to ATLAS's global production and analysis processing system, enabling a rich physics programme including the discovery of the Higgs-like boson in 2012. The wealth of accumulated experience in global data-intensive computing at this massive scale, and the considerably more challenging requirements of LHC computing from 2015 when the LHC resumes operation, are driving a comprehensive design and development cycle to prepare a revised computing model together with data processing and management systems able to meet the demands of higher trigger rates, e...
Nairz, A; The ATLAS collaboration
Student Career Experience Program | National Nuclear Security...
This program gives you the opportunity to combine your academic studies with on-the-job training and experience directly related to your academic program. You will have the...
Solar axion search with the CAST experiment
The CAST (CERN Axion Solar Telescope) experiment is searching for solar axions by their conversion into photons inside the magnet pipe of an LHC dipole. The analysis of the data recorded during the first phase of the experiment with vacuum in the magnet pipes has resulted in the most restrictive experimental limit on the coupling constant of axions to photons. In the second phase, CAST is operating with a buffer gas inside the magnet pipes in order to extent the sensitivity of the experiment to higher axion masses. We will present the first results on the $^{4}{\\rm He}$ data taking as well as the system upgrades that have been operated in the last year in order to adapt the experiment for the $^{3}{\\rm He}$ data taking. Expected sensitivities on the coupling constant of axions to photons will be given for the recent $^{3}{\\rm He}$ run just started in March 2008.
CAST Collaboration; E. Arik; S. Aune; D. Autiero; K. Barth; A. Belov; B. Beltr�n; S. Borghi; F. S. Boydag; H. Br�uninger; G. Cantatore; J. M. Carmona; S. A. Cetin; J. I. Collar; T. Dafni; M. Davenport; L. Di Lella; O. B. Dogan; C. Eleftheriadis; N. Elias; G. Fanourakis; E. Ferrer-Ribas; H. Fischer; J. Franz; J. Gal�n; E. Gazis; T. Geralis; I. Giomataris; S. Gninenko; H. G�mez; M. Hasinoff; F. H. Heinsius; I. Hikmet; D. H. H. Hoffmann; I. G. Irastorza; J. Jacoby; K. Jakov?i?; D. Kang; T. Karageorgopoulou; M. Karuza; K. K�nigsmann; R. Kotthaus; M. Kr?mar; K. Kousouris; M. Kuster; B. Laki?; C. Lasseur; A. Liolios; A. Ljubi?i?; V. Lozza; G. Lutz; G. Luz�n; D. Miller; J. Morales; T. Niinikoski; A. Nordt; A. Ortiz; T. Papaevangelou; M. J. Pivovaroff; A. Placci; G. Raiteri; G. Raffelt; H. Riege; A. Rodr�guez; J. Ruz; I. Savvidis; Y. Semertzidis; P. Serpico; S. K. Solanki; R. Soufli; L. Stewart; M. Tsagri; K. van Bibber; J5D. Villar; J. Vogel; L. Walckiers; K. Zioutas
The Mixed-Phase Arctic Cloud Experiment
The Mixed-Phase Arctic Cloud Experiment (M-PACE) was conducted from 27 September through 22 October 2004 over the Department of Energy's Atmospheric Radiation Measurement (ARM) Climate Research Facility (ACRF) on the North Slope of Alaska. The ...
J. Verlinde; J. Y. Harrington; V. T. Yannuzzi; A. Avramov; S. Greenberg; S. J. Richardson; C. P. Bahrmann; G. M. McFarquhar; G. Zhang; N. Johnson; M. R. Poellot; J. H. Mather; D. D. Turner; E. W. Eloranta; D. C. Tobin; R. Holz; B. D. Zak; M. D. Ivey; A. J. Prenni; P. J. DeMott; J. S. Daniel; G. L. Kok; K. Sassen; D. Spangenberg; P. Minnis; T. P. Tooman; M. Shupe; A. J. Heymsfield; R. Schofield
HEPEX: The Hydrological Ensemble Prediction Experiment
The Hydrological Ensemble Prediction Experiment (HEPEX) is an international project to advance technologies for hydrological forecasting. Its goal is �to bring the international hydrological and meteorological communities together to demonstrate ...
John C. Schaake; Thomas M. Hamill; Roberto Buizza; Martyn Clark
Lagged Average Predictions in a Predictability Experiment
Lagged average predictions are examined here within the context of an idealized predictability experiment. Lagged predictions contribute to making better forecasts than the forecasts obtained from using only the latest initial state. Analytic ...
John O. Roads
SLAC National Accelerator Laboratory - CERN: Experiments Observe...
CERN: Experiments Observe Particle Consistent with Long-sought Higgs Boson July 5, 2012 from CERN At a seminar held at CERN as a curtain raiser to the year's major particle physics...
TELEX The Thunderstorm Electrification and Lightning Experiment
The field program of the Thunderstorm Electrification and Lightning Experiment (TELEX) took place in central Oklahoma, May�June 2003 and 2004. It aimed to improve understanding of the interrelationships among microphysics, kinematics, ...
Donald R. MacGorman; W. David Rust; Conrad L. Ziegler; Edward R. Mansell; Terry J. Schuur; Michael I. Biggerstaff; Jerry M. Straka; Eric C. Bruning; Kristin M. Kuhlman; Nicole R. Lund; Clark Payne; Nicholas S. Biermann; William H. Beasley; Larry D. Carey; Paul R. Krehbiel; William Rison; Kenneth B. Eack
Exploring the user experience through collage
We explore the use of collage in requirements elicitation, as a tool to support potential end-users in expressing their impressions, understanding, and emotions regarding a system. Keywords: cultural probes, experience-centered design, phenomenology, requirements elicitation, thematic analysis
Dana McKay; Sally Jo Cunningham; Kirsten Thomson
The Immigration Experience in Saskatchewan's Labour Market
The Immigration Experience in Saskatchewan's Labour Market Douglas Durst Faculty of Social Work April 2008 #12;© April 2008, Douglas Durst All rights reserved Douglas Durst doug.durst
Argerami, Martin
Data Assimilation and Model Evaluation Experiment Datasets
The Institute for Naval Oceanography, in cooperation with Naval Research Laboratories and universities, executed the Data Assimilation and Model Evaluation Experiment (DAM�E) for the Gulf Stream region during fiscal years 1991�1993. Enormous ...
Chung-Chieng A. Lai; Wen Qian; Scott M. Glenn
Operating Experience Summary 2003-17
OPERATING EXPERIENCE SUMMARY U.S. Department of Energy Office of Environment, Safety and Health OE Summary 2003-17 August 25, 2003 * Underrated and unmaintained hoist used to lift...
Large-Scale Hydrogen Combustion Experiments
Large-scale combustion experiments show that deliberate ignition can limit hydrogen accumulation in reactor containments. The collected data allow accurate evaluation of containment pressures and temperatures associated with hydrogen combustion.
The Atlantic Stratocumulus Transition Experiment�ASTEX
The Atlantic Stratocumulus Experiment (ASTEX) was conducted over the northeast Atlantic Ocean during June 1992 with substantial international collaboration. The main goal of ASTEX was to study the climatologically important transition between ...
Bruce A. Albrecht; Christopher S. Bretherton; Doug Johnson; Wayne H. Scubert; A. Shelby Frisch
User experience design of complex systems
Over recent years, the global marketplace and its consumers have developed a mutual recognition for the rising prominence of design that delivers high quality user experience. For the provider of products and services, ...
Reily, Todd R. (Todd Richard)
Fermilab | Science at Fermilab | Experiments & Projects | Proposed...
Frontier Proposed Projects and Experiments LBNE Mu2e Project X NOvA MicroBooNE MICE Dark Energy Survey LSST The MINERvA Full Module Prototype plane moves into the NuMI...
The First Experiment at the LCLS
| 2003 | 2002 | 2001 2000 Subscribe to APS News rss feed The First Experiment at the LCLS SEPTEMBER 29, 2009 Bookmark and Share Standing left to right: Elliot Kanter, Robin...
The CarboEurope Regional Experiment Strategy
Quantification of sources and sinks of carbon at global and regional scales requires not only a good description of the land sources and sinks of carbon, but also of the synoptic and mesoscale meteorology. An experiment was performed in Les ...
A. J. Dolman; L. Tolk; R. Ronda; J. Noilhan; C. Sarrat; A. Brut; B. Piguet; P. Durand; A. Butet; N. Jarosz; Y. Brunet; D. Loustau; E. Lamaud; F. Miglietta; B. Gioli; V. Magliulo; M. Esposito; C. Gerbig; S. K�rner; P. Glademard; M. Ramonet; P. Ciais; B. Neininger; R. W. A. Hutjes; J. A. Elbers; R. Macatangay; O. Schrems; G. P�rez-Landa; M. J. Sanz; Y. Scholz; G. Facon; E. Ceschia; P. Beziat
The THORPEX Observation Impact Intercomparison Experiment
An experiment is being conducted to directly compare the impact of all assimilated observations on short-range forecast errors in different forecast systems using an adjoint-based technique. The technique allows detailed comparison of observation ...
Ronald Gelaro; Rolf H. Langland; Simon Pellerin; Ricardo Todling
Students gain work experience at WIPP
Students Gain Work Experience at WIPP Students Gain Work Experience at WIPP CARLSBAD, N.M., January 10, 2000 -- Students from two Eddy County high schools are gaining valuable experience by spending time with employees of the Westinghouse Waste Isolation Division and Day & Zimmermann, LLC at the Waste Isolation Pilot Plant (WIPP). Six students from Carlsbad High School and four students from Loving High School are participating in the 1999-2000 WIPP Shadow Program. A "shadow" is a student who teams up with an employee to gain hands-on experience in the workplace. This activity helps the students identify career options and develop confidence. Each student spends three days during the school year with a volunteer mentor at the work location. "This program offers our employees the opportunity to share their knowledge and
ARM - Field Campaign - Aerosol Lidar Validation Experiment -...
govCampaignsAerosol Lidar Validation Experiment - ALIVE Campaign Links ALIVE Website Comments? We would love to hear from you Send us a note below or call us at 1-888-ARM-DATA....
Experiments with interacting Bose and Fermi gases
In the past few years, the study of trapped fermionic atoms evolved from the first cooling experiments which produced quantum degenerate samples to becoming one of the most exciting branches of current atomic physics ...
Stan, Claudiu Andrei
Yankee Rowe Decommissioning Experience Record: Volume 2
This report describes Yankee Atomic Electric Company's (YAEC) recent experiences in the process of decommissioning the Yankee Rowe nuclear power plant. This volume supplements Volume 1 by presenting more lessons learned during work finished by September 1998. In 1999, EPRI will publish a final report completing the experience record. The recommendations and insights in this report will be valuable to other utilities with permanently shut down plants.
Plasma flow switch experiment on Procyon
This report presents the results obtained from a series of plasma flow switch experiments done on the Procyon explosive pulse power generator. These experiments involved switching into a fixed inductance dummy load and also into a dynamic implosion load. The results indicated that the switch did fairly well at switching current into the load, but the results for the implosion are more ambiguous. The results are compared to calculations and the implications for future plasma flow switch work are discussed.
Benage, J.F. Jr.; Bowers, R.; Peterson, D. [and others
The KATRIN Experiment: Status and Outlook
The KATRIN experiment, presently under construction in Karlsruhe, Germany, will improve on previous laboratory limits on the neutrino mass by a factor of ten. KATRIN will use a high-activity, gaseous T2 source and a very high-resolution spectrometer to measure the shape of the high-energy tail of the tritium-decay beta spectrum. The shape measurement will also be sensitive to new physics, including sterile neutrinos and Lorentz violation. This report summarizes recent progress in the experiment.
Parno, D S
D. S. Parno
The ATLAS Experiment on YouTube
DOE Data Explorer (OSTI)
ATLAS is a particle physics experiment at the Large Hadron Collider at CERN. The ATLAS detector is searching for new discoveries in the head-on collisions of protons of extraordinarily high energy. ATLAS will learn about the basic forces that have shaped our Universe since the beginning of time and that will determine its fate. Among the possible unknowns are the origin of mass, extra dimensions of space, unification of fundamental forces, and evidence for dark matter candidates in the Universe [copied from http://atlas.ch/]. Approximately 700 physicists, engineers and graduate students from 44 U.S. institutions, including four DOE laboratories, participate in the ATLAS collaboration. In addition to the Collaboration's home page and numerous ATLAS-related pages at the various research organizations involved, there are two primary ATLAS websites that provide the full range of information about this experiment at the Large Hadron Collider in at CERN, Switzerland. The main ATLAS Experiment page hosted by CERN is found at http://atlas.ch/, while the home page specifically for the U.S. contribution to ATLAS is at http://www.uslhc.us/The_US_and_the_LHC/Experiments/ATLAS. Likewise, videos and multimedia from the inception and construction of ATLAS and continuing on through current operations and scientific discoveries are found everywhere from Brookhaven Lab to YouTube to an official collection at the ATLAS Experiment page at CERN. This DDE record guides you to the ATLAS Experiment Channel on YouTube.
Statistical design of a uranium corrosion experiment
This work supports an experiment being conducted by Roland Schulze and Mary Ann Hill to study hydride formation, one of the most important forms of corrosion observed in uranium and uranium alloys. The study goals and objectives are described in Schulze and Hill (2008), and the work described here focuses on development of a statistical experiment plan being used for the study. The results of this study will contribute to the development of a uranium hydriding model for use in lifetime prediction models. A parametric study of the effect of hydrogen pressure, gap size and abrasion on hydride initiation and growth is being planned where results can be analyzed statistically to determine individual effects as well as multi-variable interactions. Input to ESC from this experiment will include expected hydride nucleation, size, distribution, and volume on various uranium surface situations (geometry) as a function of age. This study will also address the effect of hydrogen threshold pressure on corrosion nucleation and the effect of oxide abrasion/breach on hydriding processes. Statistical experiment plans provide for efficient collection of data that aids in understanding the impact of specific experiment factors on initiation and growth of corrosion. The experiment planning methods used here also allow for robust data collection accommodating other sources of variation such as the density of inclusions, assumed to vary linearly along the cast rods from which samples are obtained.
Wendelberger, Joanne R [Los Alamos National Laboratory; Moore, Leslie M [Los Alamos National Laboratory
AGR-1 Irradiation Experiment Test Plan
This document presents the current state of planning for the AGR-1 irradiation experiment, the first of eight planned irradiations for the Advanced Gas Reactor (AGR) Fuel Development and Qualification Program. The objectives of the AGR-1 experiment are: 1. To gain experience with multi-capsule test train design, fabrication, and operation with the intent to reduce the probability of capsule or test train failure in subsequent irradiation tests. 2. To irradiate fuel produced in conjunction with the AGR fuel process development effort. 3. To provide data that will support the development of an understanding of the relationship between fuel fabrication processes, fuel product properties, and irradiation performance. In order to achieve the test objectives, the AGR-1 experiment will be irradiated in the B-10 position of the Advanced Test Reactor (ATR) at the Idaho National Laboratory (INL). The test will contain six independently controlled and monitored capsules. Each capsule will contain a single type, or variant, of the AGR coated fuel. The irradiation is planned for about 700 effective full power days (approximately 2.4 calendar years) with a time-averaged, volume-average temperature of approximately 1050 �C. Average fuel burnup, for the entire test, will be greater than 17.7 % FIMA, and the fuel will experience fast neutron fluences between 2.4 and 4.5 x 1025 n/m2 (E>0.18 MeV).
John T. Maki
The technical analyses in support of U.S. energy conservation standards for residential appliances and commercial equipment have typically assumed that manufacturing costs and retail prices remain constant during the projected 30-year analysis period. There is, however, considerable evidence that this assumption does not reflect real market prices. Costs and prices generally fall in relation to cumulative production, a phenomenon known as experience and modeled by a fairly robust empirical experience curve. Using price data from the Bureau of Labor Statistics, and shipment data obtained as part of the standards analysis process, we present U.S. experience curves for room air conditioners, clothes dryers, central air conditioners, furnaces, and refrigerators and freezers. These allow us to develop more representative appliance price projections than the assumption-based approach of constant prices. These experience curves were incorporated into recent energy conservation standards for these products. The impact on the national modeling can be significant, often increasing the net present value of potential standard levels in the analysis. In some cases a previously cost-negative potential standard level demonstrates a benefit when incorporating experience. These results imply that past energy conservation standards analyses may have undervalued the economic benefits of potential standard levels.
Garbesi, Karina; Chan, Peter; Greenblatt, Jeffery; Kantner, Colleen; Lekov, Alex; Meyers, Stephen; Rosenquist, Gregory; Buskirk, Robert Van; Yang, Hung-Chia; Desroches, Louis-Benoit
Data Quality of Quality Measurement Experiments
Data Quality of Quality Measurement Experiments Data Quality of Quality Measurement Experiments S. Bottone and S. Moore Mission Research Corporation Santa Barbara, California Introduction Quality Measurement Experiments (QME) are a special class of Value-Added Products (VAP). QMEs add value to Atmospheric Radiation Measurement (ARM) Program datastreams by providing for continuous assessment of the quality of incoming data based on internal consistency checks, comparisons between independent similar measurements, or comparisons between measurements and modeled results. Like any datastream, QME datastreams need to be checked for data quality. For each QME, we analyze a representative sample of files from the ARM data archive to determine 'typical' values of the QME variables. We then design outlier tests, specific to each variable, to be applied to
Fuel Cell Power Plant Experience Naval Applications
clean clean Fuel Cell Power Plant Experience Naval Applications US Department of Energy/ Office of Naval Research Shipboard Fuel Cell Workshop Washington, DC March 29, 2011 FuelCell Energy, the FuelCell Energy logo, Direct FuelCell and "DFC" are all registered trademarks (®) of FuelCell Energy, Inc. *FuelCell Energy, Inc. *Renewable and Liquid Fuels Experience *HTPEM Fuel Cell Stack for Shipboard APU *Solid Oxide Experience and Applications DOE-ONR Workshop FuelCell Energy, the FuelCell Energy logo, Direct FuelCell and "DFC" are all registered trademarks (®) of FuelCell Energy, Inc. FuelCell Energy, Inc. * Premier developer of fuel cell technology - founded in 1969 * Over 50 power installations in North America, Europe, and Asia * Industrial, commercial, utility
Research Laboratory Experiments with Energy Efficiency Upgrades |
Research Laboratory Experiments with Energy Efficiency Upgrades Research Laboratory Experiments with Energy Efficiency Upgrades Research Laboratory Experiments with Energy Efficiency Upgrades August 30, 2012 - 11:52am Addthis Energy efficiency upgrades -- such as geothermal heating and cooling, nanogel-filled windows, and lighting sensors -- will help the University of Kentucky Center for Applied Energy Research reduce energy use and save money. | Photo courtesy of the University of Kentucky. Energy efficiency upgrades -- such as geothermal heating and cooling, nanogel-filled windows, and lighting sensors -- will help the University of Kentucky Center for Applied Energy Research reduce energy use and save money. | Photo courtesy of the University of Kentucky. Julie McAlpin Communications Liaison, State Energy Program
Argonne CNM: End-of-Experiment Survey
End-of-Experiment Survey End-of-Experiment Survey Project Information 1. What is your proposal number? Administrative Support 1. The processing of my experiment proposal was: Excellent Satisfactory Marginal Unsatisfactory 2. The efficiency of the processing and orientation procedure was: Excellent Satisfactory Marginal Unsatisfactory 3. The documentation available on the CNM web site to prepare you for your visit was: Excellent Satisfactory Marginal Unsatisfactory Comments about overall support: Environment, Safety and Health (ES&H) 1. The safety review/work authorization process was: Excellent Satisfactory Marginal Unsatisfactory Comments on safety review, including suggested improvements to the forms used: 2. With respect to stated objectives, the content provided in ESH 100U and CNM User Orientation is:
Apply for Our Jobs > How to Apply > Student Apply for Our Jobs > How to Apply > Student Jobs > Student Career Experience Program Student Career Experience Program We have a limited number of Student Career Experience Program (SCEP) positions that are located in the greater Washington, D.C. area and in Albuquerque, N.M. Other locations may include Kansas City, Mo.; Livermore, Calif.; Los Alamos, N.M.; Las Vegas, Nev.; Amarillo, Texas; Aiken, S.C.; and Oak Ridge, Tenn. We work with local universities to recruit students for this program. Please contact your university's career center to see if NNSA is a partner with your school. SCEP positions must be directly related to your academic program. For SCEP eligibility you must be: a United States citizen; enrolled as a diploma or degree-seeking undergraduate or graduate
Microprocessors in physics experiments at SLAC
The increasing size and complexity of high energy physics experiments is changing the way data are collected. To implement a trigger or event filter requires complex logic which may have to be modified as the experiment proceeds. Simply to monitor a detector, large amounts of data must be processed on line. The use of microprocessors or other programmable devices can help to achieve these ends flexibly and economically. At SLAC, a number of microprocessor-based systems have been built and are in use in experimental setups, and others are now being developed. This talk is a review of existing systems and their use in experiments, and of developments in progress and future plans.
Rochester, L.S.
The problem of current continuity and viscous drag at the boundaries in rotating-plasma experiments is discussed. A hypothetical model having a steady state with axial symmetry is emphasized; it is shown that the discharge impedance derived from this model does not agree with many observations. The Homopolar III'' experiment is described in which the flux surfaces were strongly convex and parallel to the toroidal-shaped electrodes. In this way friction at the insulators was reduced. But the structure of the discharge deviated drastically from axial symmetry near the outer surface. Several studies led to the conclusion that the flow pattern probably involved secondary flows. A detailed analysis of this structure was not possible. It was also found that the rotational speed could not be raised above a few cm/ mu sec because the insulators failed in spite of the special design of the experiment. 28 references. (auth)
Kunkel, W.B.; Baker, W.R.; Bratenahl, A.; Halbach, K.
Neutrino Oscillation Experiments at Nuclear Reactors
In this paper I give an overview of the status of neutrino oscillation experiments performed using nuclear reactors as sources of neutrinos. I review the present generation of experiments (Chooz and Palo Verde) with baselines of about 1 km as well as the next generation that will search for oscillations with a baseline of about 100 km. While the present detectors provide essential input towards the understanding of the atmospheric neutrino anomaly, in the future, the KamLAND reactor experiment represents our best opportunity to study very small mass neutrino mixing in laboratory conditions. In addition KamLAND with its very large fiducial mass and low energy threshold, will also be sensitive to a broad range of different physics.
Giorgio Gratta
The Washington State Experience Energy Code Compliance
Washington State Experience Washington State Experience Residential Energy Code Compliance Gary Nordeen Senior Building Science Specialist April 4, 2013 WSU Energy Program Provides energy services, products, education and information for: * Businesses * Utilities ̶ public and private * Governments ̶ state and local * Tribes * Federal agencies * Manufacturing plants * Educational facilities * National laboratories WSU Energy Program Building Science Team * Residential energy code technical assistance * Voluntary programs, Northwest ENERGYSTAR Homes * Research and development, Building America * Community-based upgrade programs * Industry training and certifications ̶ HERS, BPI, ENERGY STAR, PTCS Staff provides building science expertise for: WSU Energy Program
ABSTRACT: The author experimented with the dehasiddhi using mercury. The interesting experiment is narrated in this article. The land of Bharath is the only place which developed the science dealing with the metal remedies for holistic health during the Vedic period when people in other parts of the world continued to use potions and witchcraft to cure diseases of the body. This science in Vedic language is termed rasa sastra. It uses metals such as iron, copper, silver, gold mercury, elements such as iron, copper, silver, gold mercury, elements such as sulphur, mica and other materials such as shells, pearls corals jewels, salts, etc in a purified and processed form for internal
M. P Alexander
Status and Commissioning of the CMS Experiment
After a brief overview of the Compact Muon Solenoid (CMS) experiment, the status of construction and installation is described in the first part of the note. The second part of the document is devoted to a discussion of the general commissioning strategy of the CMS experiment, with a particular emphasis on trigger, calibration and alignment. Aspects of b-physics, as well as examples for early physics with CMS are also presented. CMS will be ready for data taking in time for the first collisions in the Large Hadron Collider (LHC) at CERN in late 2007.
O. Buchmueller; F. -P. Schilling
Low Energy Antiproton Experiments - A Review
Low energy antiprotons offer excellent opportunities to study properties of fundamental forces and symmetries in nature. Experiments with them can contribute substantially to deepen our fundamental knowledge in atomic, nuclear and particle physics. Searches for new interactions can be carried out by studying discrete symmetries. Known interactions can be tested precisely and fundamental constants can be extracted from accurate measurements on free antiprotons (p-bar's) and bound two- and three-body systems such as antihydrogen (H-bar = p-bare-), the antprotonic helium ion (He++p-bar)+ and the antiprotonic atomcule (He++p-bare-) . The trapping of a single p-bar in a Penning trap, the formation and precise studies of antiprotonic helium ions and atoms and recently the production of H-bar have been among the pioneering experiments. They have led already to precise values for p-bar parameters, accurate tests of bound two- and three-body Quantum Electrodynamics (QED), tests of the CPT theorem and a better understanding of atom formation from their constituents. Future experiments promise more precise tests of the standard theory and have a robust potential to discover new physics. Precision experiments with low energy p-bar's share the need for intense particle sources and the need for time to develop novel instrumentation with all other experiments, which aim for high precision in exotic fundamental systems. The experimental programs - carried out in the past mostly at the former LEAR facility and at present at the AD facility at CERN - would benefit from intense future sources of low energy p-bar's. The highest possible p-bar fluxes should be aimed for at new facilities such as the planned FLAIR facility at GSI in order to maximize the potential of delicate precision experiments to influence model building. Examples of key p-bar experiments are discussed here and compared with other experiments in the field. Among the central issues is their potential to obtain important information on basic symmetries such as CPT and to gain insights into antiparticle gravitation as well as the possibilities to learn about nuclear neutron distributions.
Jungmann, Klaus P. [Kernfysisch Versneller Instituut, Rijksuniversiteit Groningen, Zernikelaan 25, 9747AA Groningen (Netherlands)
Analysis of the Impurity Flow Reversal Experiment
Experiments performed on the Impurity Study Experiment (ISX-A) tokamak have shown that poloidally asymmetric injection of hydrogen gas can alter the inward transport of injected impurity atoms. We have compared the observed transport times and the magnitude of the flow reversal effect with a model based on the neoclassical theory of impurity transport and find that the observations are consistent with the theory. However, uncertainities in the radial profiles and the atomic rate coefficients do not permit a truly definitive test of the theory.
Burrell, K.H.; Wong, S.K.; Amano, T.
Monitoring hydraulic fracture growth: Laboratory experiments
The authors carry out small-scale hydraulic fracture experiments to investigate the physics of hydraulic fracturing. The laboratory experiments are combined with time-lapse ultrasonic measurements with active sources using both compressional and shear-wave transducers. For the time-lapse measurements they focus on ultrasonic measurement changes during fracture growth. As a consequence they can detect the hydraulic fracture and characterize its shape and geometry during growth. Hence, this paper deals with fracture characterization using time-lapse acoustic data. Hydraulic fracturing is used in the oil and gas industry to stimulate reservoir production.
Groenenboom, J.; Dam, D.B. van
Steady-State Flows in Two-Fluid Models of NSTX and DIII-D Plasmas
Presented At The 2009 International Sherwood Fusion Theory Conf., Denver, Colorado (2009)International Sherwood Fusion Theory Conference(2009) Denver Colorado, US, 2009999616425
Ferraro, N.M.
Work Control Center Operating Procedure page 1 D-NSTX-OP-AD-129 Rev.OO
drawings to be included in the EWP shall be stamped "Approved for Fabrication". (Reference: ENG-OIO. (Reference: ENG·OIO, "Control of Drawings, Software, and Finnware") 10.1.1 RevisedlVoided Drawings: 10
Particle and Energy Transport in the SOL of DIII-D and NSTX
Bull. Am. Phys. Soc. 51, 237 (2006)48th American Physical Society Annual Meeting of Division of Plasma Physics Philadelphia Pennsylvania, US, 2006999612805
Boedo, J.A.
Particle and Energy Transport in the SOL of DIII-D and NSTX (A25604)
Proc. Of 21st IAEA Fusion Energy Conf., Chengdu, China, 2006, To Be Published In Nucl. Fusion999613325
meeting of the NSTX Program Advisory Committee Princeton Plasma Physics Laboratory
lithium divertor (LLD) for particle pumping, higher-power fast-wave heating for current ramp-up studies to inform the design of a demonstration #12;fusion power plant." The ST physics issues identified to "Tame the plasma material interface" (such as NHTX), for an ST-based demonstration power plant (ST- Demo
(ESH-016) Lift Procedure (ENG-021) ES&H Review (NEPA, IH, etc.) Independent Review Pre-Job Brief D-SITE SPECIFIC: D-Site Work Permit (OP-AD-09) Door Permit (OP-G-93) USQD (OP-AD-63) Pre-Job Brief (OP-AD-79) T of the Day Meetings 12 7.2 Weekly Progress Meetings 12 7.3 Pre-job Briefings
Fast 2-D camera control, data acquisition, and database techniques for edge studies on NSTX
-by-frame examination is not practical. This paper describes image analysis, database techniques, and visualization (typically referred to as "blobs") near the plasma edge. Software tools that generate statistics of blob affect plasma confinement and heat loads on plasma facing components, and are thus of particular interest
Fast 2-D Camera Control, Data Acquisition, and Database Techniques for Edge Studies on NSTX
. This paper describes image analysis, database techniques, and visualization methods used to organize the fast") near the plasma edge. Software tools that generate statistics of blob speed, shape, amplitude, size, and orientation are described. The characteristics of emitted blobs affect plasma confinement and heat loads
Simulation of Non-resonant Internal Kink Mode with Toroidal Rotation in NSTX
Plasmas in spherical and conventional tokamaks, with weakly reversed shear q pro le and minimum q above but close to unity, are susceptible to an non-resonant (m, n ) = (1, 1) internal kink mode. This mode can saturate and persist and can induce a (2; 1) seed island for Neoclassical Tearing Mode (NTMs)1 . The mode can also lead to large energetic particle transport and signi cant broadening of beam-driven current. Motivated by these important e ects, we have carried out extensive nonlinear simulations of the mode with nite toroidal rotation using parameters and pro les of an NTSX plasma with a weakly reversed shear pro le. The numerical results show that, at the experimental level, plasma rotation has little e ect on either equilibrium or linear stability. However, rotation can signi cantly inuence the nonlinear dynamics of the (1, 1) mode and the the induced (2, 1) magnetic island. The simulation results show that a rotating helical equilibrium is formed and maintained in the nonlinear phase at nite plasma rotation. In contrast, for non-rotating cases, the nonlinear evolution exhibits dynamic oscillations between a quasi-2D state and a helical state. Furthermore, the e ects of rotation are found to greatly suppress the (2, 1) magnetic island even at a low level.
Fu, Guoyong
Phase-one experiment test plan solar photovoltaic/thermal residential experiment
Objectives, rationale, and method of a one-year experiment using a residential photovoltaic/thermal power system are presented. Data will be both archived and processed to investigate: (1) series heat pump system performance, and (2) electric utility impacts. A parallel heat pump system will be investigated in a subsequent experiment.
Kern, E.C. Jr.
Heart Failure:Heart Failure: The Patient's ExperienceThe Patient's Experience
1 Heart Failure:Heart Failure: The Patient's ExperienceThe Patient's Experience Jason Ryan, MD, MPHJason Ryan, MD, MPH CoCo--director, UCONN Heart Failure Centerdirector, UCONN Heart Failure Center,084,000 $34.8 billion Background on Heart FailureBackground on Heart Failure 1 Heart failure (HF) is a major
Oliver, Douglas L.
A Microscopic Double-Slit Experiment
A Microscopic Double-Slit Experiment Print A Microscopic Double-Slit Experiment Print Two centuries ago, Thomas Young performed the classic demonstration of the wave nature of light. He placed a screen with two tiny slits in front of a single light source, effectively converting it into a two-centered source. On a second screen far away, he saw a pattern of light and dark diffraction fringes, a well-known hallmark of wave interference. Along with later studies using particles instead of light, the experiment played a crucial role in establishing the validity of wave-particle duality, a puzzling concept that has ultimately become central to the interpretation of complementarity in quantum mechnanics. In a new twist on this classic experiment, the double slit (with light waves) has been replaced by a diatomic molecule (with electron waves). At ALS Beamline 10.0.1, researchers have shown that diatomic molecules can serve as two-center emitters of electron waves and that traces of electron-wave interference can be directly observed in precise measurements of vibrationally resolved photoionization spectra.
A Microscopic Double-Slit A Microscopic Double-Slit Experiment A Microscopic Double-Slit Experiment Print Wednesday, 29 February 2012 00:00 Two centuries ago, Thomas Young performed the classic demonstration of the wave nature of light. He placed a screen with two tiny slits in front of a single light source, effectively converting it into a two-centered source. On a second screen far away, he saw a pattern of light and dark diffraction fringes, a well-known hallmark of wave interference. Along with later studies using particles instead of light, the experiment played a crucial role in establishing the validity of wave-particle duality, a puzzling concept that has ultimately become central to the interpretation of complementarity in quantum mechnanics. In a new twist on this classic experiment, the double slit (with light waves) has been replaced by a diatomic molecule (with electron waves). At ALS Beamline 10.0.1, researchers have shown that diatomic molecules can serve as two-center emitters of electron waves and that traces of electron-wave interference can be directly observed in precise measurements of vibrationally resolved photoionization spectra.
The Earth Radiation Budget Experiment (ERBE)
The Earth Radiation Budget Experiment (ERBE) is the first multi-satellite system designed to measure the Earth's radiation budget. It will fly on a low-inclination NASA satellite and two Sun-synchronous NOAA satellites during the mid-1980s. Each ...
Bruce R. Barkstrom
The ambient wood journals: replaying the experience
The Ambient Wood project aims to facilitate a learning experience using an adaptive infrastructure in an outdoor environment. This involves sensor technology, virtual world orchestration, and a wide range of devices ranging from hand-held computers to ... Keywords: adaptive infrastructure, consolidation, record and replay, storytelling
Mark J. Weal; Danius T. Michaelides; Mark K. Thompson; David C. DeRoure
Idealized Test Cases for Dynamical Core Experiments
Idealized Test Cases for Dynamical Core Experiments Christiane Jablonowski (University of Michigan-13/2006 #12;Motivation · Test cases for 3D dynamical cores on the sphere are hard to find in the literature groups lack standardized & easy-to-use analysis techniques · Idea: Establish a collection of test cases
Jablonowski, Christiane
ALEGRA -- code validation: Experiments and simulations
In this study, the authors are providing an experimental test bed for validating features of the ALEGRA code over a broad range of strain rates with overlapping diagnostics that encompass the multiple responses. A unique feature of the Arbitrary Lagrangian Eulerian Grid for Research Applications (ALEGRA) code is that it allows simultaneous computational treatment, within one code, of a wide range of strain-rates varying from hydrodynamic to structural conditions. This range encompasses strain rates characteristic of shock-wave propagation (10{sup 7}/s) and those characteristic of structural response (10{sup 2}/s). Most previous code validation experimental studies, however, have been restricted to simulating or investigating a single strain-rate regime. What is new and different in this investigation is that the authors have performed well-instrumented experiments which capture features relevant to both hydrodynamic and structural response in a single experiment. Aluminum was chosen for use in this study because it is a well characterized material--its EOS and constitutive material properties are well defined over a wide range of loading rates. The current experiments span strain rate regimes of over 10{sup 7}/s to less than 10{sup 2}/s in a single experiment. The input conditions are extremely well defined. Velocity interferometers are used to record the high strain-rate response, while low strain rate data were collected using strain gauges.
Chhabildas, L.C.; Konrad, C.H.; Mosher, D.A.; Reinhart, W.D; Duggins, B.D.; Rodeman, R.; Trucano, T.G.; Summers, R.M.; Peery, J.S.
Turning exams into a learning experience
Most students see exams as a stressful experience, having crammed as much as they possibly can and hoping that the material they have studied would indeed be on the exams, and the material that they did not have the time to study for, nor understand, ... Keywords: assessment, learning, midterms, peer-instruction, two-stage exams
Benjamin Yu; George Tsiknis; Meghan Allen
MEG Experiment?New Result and Prospects?
The MEG Experiment searches for a lepton flavour violating muon decay ? + ???e + ? with a branching ratio sensitivity of 10 ?13 in order to explore the parameter region predicted by many theoretical models beyond the Standard Model. The first physics run has been performed in 2008
Hajime Nishiguchi; The MEG collaboration
Light Duty Truck Aftertreatment - Experience and Challenges
Detroit Diesel's test experience on light duty truck PM aftertreatment technology development will be presented. The Tier-II extremely low emissions standards combined with the light-duty test cycle impose a significant challenge for the development of production-viable emissions technologies. A robust general path to achieve these emissions targets will be outlined.
Redon, Fabien
Combustion Turbine Experience and Intelligence Report: 2011
Along with up-to-date information on trends in gas markets in the United States and around the world, the 2011 edition of the Combustion Turbine Experience and Intelligence Report (CTEIR) addresses the impact of shales on natural gas markets and associated risks and includes an overview of boiler windbox repowering using gas turbines.
APPENDIX 47 APPENDIX MAGNETIC EXPERIMENTS1,2 INTRODUCTION As noted in the Handbook for Shipboard. It has frequently been suggested that the repeated banging of the APC bar- rel as it passes up the pipe, the core is in the magnetic field of the APC barrel and the field of the drill pipe that leaks through
Preparing for Decommissioning: The Oyster Creek Experience
This report chronicles the process of preparing GPU Nuclear's Oyster Creek Nuclear Generating Station for early retirement and decommissioning. The Oyster Creek experience has great relevance to the nuclear industry, as future decommissioning projects will benefit from the comprehensive preplanning work performed there.
Decommissioning Experiences and Lessons Learned: Decommissioning Costs
In 1995, the United States (US) Nuclear Regulatory Commission (NRC) issued revised decommissioning regulations that provided a dose-based site release limit and detailed supporting regulatory guidance. This report summarizes the decommissioning cost experiences at US nuclear plants, including information about radwaste volumes and the cost of radwaste disposal based on the current regulatory situation in the US.
US graphite reactor D&D experience
This report describes the results of the U.S. Graphite Reactor Experience Task for the Decommissioning Strategy Plan for the Leningrad Nuclear Power Plant (NPP) Unit 1 Study. The work described in this report was performed by the Pacific Northwest National Laboratory (PNNL) for the Department of Energy (DOE).
Garrett, S.M.K.; Williams, N.C.
Dry Ice vs. Pipette Experiment Description
Dry Ice vs. Pipette Experiment Description Dry ice (solid) is put into the bulb of a pipette, plastic pipette 1 ice cube sized piece of dry ice Butter knife (or some object to break dry ice) Gloves (surgical gloves will not work, they must protect hands from dry ice) Safety glasses for demonstrator
Determining Supersymmetric Parameters With Dark Matter Experiments
In this article, we explore the ability of direct and indirect dark matter experiments to not only detect neutralino dark matter, but to constrain and measure the parameters of supersymmetry. In particular, we explore the relationship between the phenomenological quantities relevant to dark matter experiments, such as the neutralino annihilation and elastic scattering cross sections, and the underlying characteristics of the supersymmetric model, such as the values of {mu} (and the composition of the lightest neutralino), m{sub A} and tan {beta}. We explore a broad range of supersymmetric models and then focus on a smaller set of benchmark models. We find that by combining astrophysical observations with collider measurements, {mu} can often be constrained far more tightly than it can be from LHC data alone. In models in the A-funnel region of parameter space, we find that dark matter experiments can potentially determine m{sub A} to roughly {+-}100 GeV, even when heavy neutral MSSM Higgs bosons (A, H{sub 1}) cannot be observed at the LHC. The information provided by astrophysical experiments is often highly complementary to the information most easily ascertained at colliders.
Hooper, Dan; /Fermilab; Taylor, Andrew M.; /Oxford U.
Combustion Turbine Experience and Intelligence Reports: 2009
Along with up-to-date information on trends in gas markets in the United States and around the world, the 2009 edition of the Combustion Turbine Experience and Intelligence Report (CTEIR) addresses developments in natural gas supply fundamentals, extending plant depreciable life, and CO2 capture for combined cycles.
Convection Initiation and Downburst Experiment (CINDE)
The Convection Initiation and Downburst Experiment (CINDE) was conducted in the Denver, Colorado area from 22 June to 7 August 1987 to study processes leading to the formation of deep convection and the physics of downbursts. A total of 6 Doppler ...
James W. Wilson; James A. Moore; G. Brant Foote; Brooks Martner; Taneil Uttal; James M. Wilczak; Alfred R. Rodi
Managing ERP configuration variants: an experience report
The concepts of Software Product Line Engineering (SPLE) have been adapted and applied to enterprise IT systems, in particular the ERP systems of a production company. Based on a 2-layer feature model for the domain of the company's business processes, ... Keywords: IT management, enterprise resource planning, experience report, software product line engineering
Andrea Leitner; Christian Kreiner
Organizational Learning: From Experience to Knowledge
Organizational learning has been an important topic for the journal Organization Science and for the field. We provide a theoretical framework for analyzing organizational learning. According to the framework, organizational experience interacts ... Keywords: creativity, innovation, knowledge transfer, learning curves, organizational learning, organizational memory
Linda Argote; Ella Miron-Spektor
Liner target interaction experiments on Pegasus II
The Los Alamos High Energy Density Physics program uses capacitively driven low voltage, inductive-storage pulse power to implode cylindrical targets for hydrodynamics experiments. Once a precision driver liner was characterized an experimental series characterizing the aluminum target dynamics was performed. The target was developed for shock-induced quasi-particle ejecta experiments including holography. The concept for the Liner shock experiment is that the driver liner is used to impact the target liner which then accelerates toward a collimator with a slit in it. A shock wave is set up in the target liner and as the shock emerges from the back side of the target liner, ejecta are generated. By taking a laser hologram the particle distribution of the ejecta are hoped to be determined. The goal for the second experimental series was to characterize the target dynamics and not to measure and generate the ejecta. Only the results from the third shot, Pegasus II-26 fired April 26th, 1994, from the series is discussed in detail. The second experimental series successfully characterized the target dynamics necessary to move forward towards the planned quasi-ejecta experiments.
Hockaday, M.P.; Chrien, R.E.; Bartsch, R. [and others
Belle II Experiment Network and Computing
The Belle experiment, part of a broad-based search for new physics, is a collaboration of approximately 400 physicists from 55 institutions across four continents. The Belle detector is located at the KEKB accelerator in Tsukuba, Japan. The Belle detector was operated at the asymmetric electron-positron collider KEKB from 1999-2010. The detector accumulated more than 1/ab of integrated luminosity corresponding to more than 2 PB of data near 10 GeV center-of-mass energy. Recently, KEK has initiated a $400 million accelerator upgrade to be called SuperKEKB, designed to produce instantaneous and integrated luminosity two orders of magnitude greater than KEKB. The new international collaboration at SuperKEKB is called Belle II. The first data from Belle II/SuperKEKB is expected in 2015. In October 2012, senior members of the Belle II collaboration gathered at PNNL to discuss the computing and networking requirements of the Belle II experiment with ESnet staff and other computing and networking experts. The day-and-a-half-long workshop characterized the instruments and facilities used in the experiment, the process of science for Belle II, and the computing and networking equipment and configuration requirements to realize the full scientific potential of the collaboration's work. The requirements identified at the Belle II Experiment Requirements workshop are summarized in this report.
David M. Asner; Eli Dart; Takanori Hara
Pebble Flow Experiments For Pebble Bed Reactors
Pebble Flow Experiments For Pebble Bed Reactors Andrew C. Kadak1 Department of Nuclear Engineering of Technology 2nd International Topical Meeting on High Temperature Reactor Technology Institute of Nuclear in such a reactor would conform to granular flow theory which suggested rapid mixing as opposed to linear flow lines
Bazant, Martin Z.
Gain International Work Experience in China
Gain International Work Experience in China www.StudyCLI.org "The CLI internship gave me a huge boost both personally and professionally. At 21 years old, I've lived in China and can speak basic city of Guilin, China. CLIinternsengageinadynamicrangeofprojects: Y Establishnewrelationshipswith
Virginia Tech
Sharing the viewing experience through second screens
Despite the ever expanding forms of digital entertainment and the emergence of consumer recording facilities, allowing viewers to time shift their TV viewing habits, there are still certain TV shows and events that create an audience desire to be part ... Keywords: interactive, mobile, narrative, performance, second screen, shared experience, television, twitter
Mark Lochrie; Paul Coulton
Reactor-based Neutrino Oscillation Experiments
The status of neutrino oscillation searches employing nuclear reactors as sources is reviewed. This technique, a direct continuation of the experiments that proved the existence of neutrinos, is today an essential tool in investigating the indications of oscillations found in studying neutrinos produced in the sun and in the earth's atmosphere. The low-energy of the reactor \
Carlo Bemporad; Giorgio Gratta; Petr Vogel
Dynamic Analysis of Learning in Behavioral Experiments
Understanding how an animal�s ability to learn relates to neural activity or is altered by lesions, different attentional states, pharmacological interventions, or genetic manipulations are central questions in neuroscience. Although learning is a dynamic process, current analyses do not use dynamic estimation methods, require many trials across many animals to establish the occurrence of learning, and provide no consensus as how best to identify when learning has occurred. We develop a state�space model paradigm to characterize learning as the probability of a correct response as a function of trial number (learning curve). We compute the learning curve and its confidence intervals using a state�space smoothing algorithm and define the learning trial as the first trial on which there is reasonable certainty (?0.95) that a subject performs better than chance for the balance of the experiment. For a range of simulated learning experiments, the smoothing algorithm estimated learning curves with smaller mean integrated squared error and identified the learning trials with greater reliability than commonly used methods. The smoothing algorithm tracked easily the rapid learning of a monkey during a single session of an association learning experiment and identified learning 2 to 4 d earlier than accepted criteria for a rat in a 47 d procedural learning experiment. Our state�space paradigm estimates learning curves for single animals, gives a precise definition of learning, and suggests a coherent statistical framework for the design and analysis of learning experiments that could reduce the number of animals and trials per animal that these studies require.
Anne C. Smith; Loren M. Frank; Sylvia Wirth; Marianna Yanike; Dan Hu; Yasuo Kubota; Ann M. Graybiel; Wendy A. Suzuki; Emery N. Brown
The Particle Adventure | How do we experiment with tiny particles...
Accelerators and particle detectors - How do we experiment with tiny particles? - Fixed target experiments In a fixed-target experiment, a charged particle such as an electron or a...
EA-1340: Conducting Astrophysics and Other Basic Science Experiments...
40: Conducting Astrophysics and Other Basic Science Experiments at the WIPP Site, Carlsbad, New Mexico EA-1340: Conducting Astrophysics and Other Basic Science Experiments at the...
A Survey of Utility Experience with Real Time Pricing
Survey of Utility Experience with Real Time Pricing List ofUtility Experience with Real Time Pricing Table of Contents Acknowledgements iii Table of Contents..v List
Barbose, Galen; Goldman, Charles; Neenan, Bernie
APS Experiment Safety Approval System Instructions for Users
form and Experiment Hazard Control Plan? Part VII: What If... APS Experiment Safety Approval System Instructions for Users version 2.0 January 21, 2005 Contacts...
EA-1108: The National Spherical Tokamah Experiment at the Princeton...
8: The National Spherical Tokamah Experiment at the Princeton Plasma Physics Laboratory, Plainsboro Township, New Jersey EA-1108: The