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Office of Scientific and Technical Information
Bio-SANS: the Biological Small-Angle Neutron Scattering Instrument...
NLE Websites -- All DOE Office Websites (Extended Search)
Biological Small-Angle Neutron Scattering Instrument at HFIR Detector tanks for the new SANS instruments at HFIR. The Bio-SANS detector is on the right. Detector tanks for the SANS...
EQ-SANS: the Extended Q-Range Small-Angle Neutron Scattering Diffractometer
The Extended Q-Range Small-Angle Neutron Scattering Diffractometer at SNS The Extended Q-Range Small-Angle Neutron Scattering Diffractometer at SNS Extended Q-Range Small Angle Diffractometer EQ-SANS detector array The EQ-SANS Diffractometer is designed to study non-crystalline, nano-sized materials in solid, liquid, or gas forms such as polymers, micelles, proteins, and other large biological molecular complexes in solution. It offers high neutron flux, high wavelength resolution (precision), and wide Q-coverage. EQSANS is located on beam line 6, viewing the top-downstream, coupled supercritical hydrogen moderator. It has a curved multichannel beam bender to avoid the direct line of sight of the moderator, which cleans out the background from the prompt neutron pulse quite effectively. The cutoff wavelength of the optics is ~1.5 Å. Above this minimum wavelength, the
The Extended Q-Range Small Angle Neutron Scattering ...
Science Conference Proceedings (OSTI)
Abstract Scope, The Extended Q-Range Small Angle Neutron Scattering Diffractometer (EQ-SANS) at the Spallation Neutron Source (SNS) is a high intensity�...
Imaging with Scattered Neutrons
E-Print Network (OSTI)
We describe a novel experimental technique for neutron imaging with scattered neutrons. These scattered neutrons are of interest for condensed matter physics, because they permit to reveal the local distribution of incoherent and coherent scattering within a sample. In contrast to standard attenuation based imaging, scattered neutron imaging distinguishes between the scattering cross section and the total attenuation cross section including absorption. First successful low-noise millimeter-resolution images by scattered neutron radiography and tomography are presented.
H. Ballhausen; H. Abele; R. Gaehler; M. Trapp; A. Van Overberghe
Neutron Scattering Facilities 1982
NEUTRON SOURCES NEUTRON SOURCES Types of Sources U.S. Sources Available for Users Plans for the Future The Neutron Scattering Society of America (NSSA) SNS/ANL School on Neutron and x-Ray Scattering, June 2011 Jim Rhyne Lujan Neutron Scattering Center Los Alamos National Lab. What do we need to do neutron scattering? * Neutron Source - produces neutrons * Diffractometer or Spectrometer - Allows neutrons to interact with sample - Sorts out discrete wavelengths by monochromator (reactor) or by time of flight (pulse source) - Detectors pick up neutrons scattered from sample * Analysis methods to determine material properties * Brain power to interpret results Sources of neutrons for scattering * Nuclear Reactor - Neutrons produced from fission of 235 U - Fission spectrum neutrons
Physics @ Oxford SCATTERING NEUTRONS
1 Neutron Scattering Society of America (NSSA) Purpose and New Initiatives www.neutronscattering.org SNS/ANL School on Neutron and X-Ray Scattering June 2011 Visit us now on Facebook #12;2 What is the NSSA? NSSA is an organization of scientists and engineers with a common interest in using neutron
Herz, Laura M.
Neutron Scattering Template
Acknowledgements The graphics used on the Neutron Scattering Web Pages were designed by Tami Sharley (Information and Publishing Services Division) and Jack Carpenter (Intense...
Neutron Scattering Web
at neutronsources.org. The information contained here in the Neutron Scattering Web has been transferred to the new site. We will leave the current content here for...
Neutron Scattering Software
Software Software A new portal for neutron scattering has just been established at neutronsources.org. The information contained here in the Neutron Scattering Web has been transferred to the new site. We will leave the current content here for archival purposes but no new content will be added. We encourage everyone interested in neutron scattering to take full advantage of this exciting new resource for our community. Neutronsources.org Data Formats NeXus: Neutron and X-ray Data Format Crystallographic Binary Format (CBF/imgCIF) Hierarchical Data Format (HDF) Data Analysis and Visualization Data Analysis for Neutron Scattering Experiments (DANSE): distributed data analysis project Large Array Manipulation Program (LAMP): IDL-based data analysis and visualization
SciTech Connect
Much of our understanding of the atomic-scale magnetic structure and the dynamical properties of solids and liquids was gained from neutron-scattering studies. Elastic and inelastic neutron spectroscopy provided physicists with an unprecedented, detailed access to spin structures, magnetic-excitation spectra, soft-modes and critical dynamics at magnetic-phase transitions, which is unrivaled by other experimental techniques. Because the neutron has no electric charge, it is an ideal weakly interacting and highly penetrating probe of matter's inner structure and dynamics. Unlike techniques using photon electric fields or charged particles (e.g., electrons, muons) that significantly modify the local electronic environment, neutron spectroscopy allows determination of a material's intrinsic, unperturbed physical properties. The method is not sensitive to extraneous charges, electric fields, and the imperfection of surface layers. Because the neutron is a highly penetrating and non-destructive probe, neutron spectroscopy can probe the microscopic properties of bulk materials (not just their surface layers) and study samples embedded in complex environments, such as cryostats, magnets, and pressure cells, which are essential for understanding the physical origins of magnetic phenomena. Neutron scattering is arguably the most powerful and versatile experimental tool for studying the microscopic properties of the magnetic materials. The magnitude of the cross-section of the neutron magnetic scattering is similar to the cross-section of nuclear scattering by short-range nuclear forces, and is large enough to provide measurable scattering by the ordered magnetic structures and electron spin fluctuations. In the half-a-century or so that has passed since neutron beams with sufficient intensity for scattering applications became available with the advent of the nuclear reactors, they have became indispensable tools for studying a variety of important areas of modern science, ranging from large-scale structures and dynamics of polymers and biological systems, to electronic properties of today's technological materials. Neutron scattering developed into a vast field, encompassing many different experimental techniques aimed at exploring different aspects of matter's atomic structure and dynamics. Modern magnetic neutron scattering includes several specialized techniques designed for specific studies and/or particular classes of materials. Among these are magnetic reflectometry aimed at investigating surfaces, interfaces, and multilayers, small-angle scattering for the large-scale structures, such as a vortex lattice in a superconductor, and neutron spin-echo spectroscopy for glasses and polymers. Each of these techniques and many others offer exciting opportunities for examining magnetism and warrant extensive reviews, but the aim of this chapter is not to survey how different neutron-scattering methods are used to examine magnetic properties of different materials. Here, we concentrate on reviewing the basics of the magnetic neutron scattering, and on the recent developments in applying one of the oldest methods, the triple axis spectroscopy, that still is among the most extensively used ones. The developments discussed here are new and have not been coherently reviewed. Chapter 2 of this book reviews magnetic small-angle scattering, and modern techniques of neutron magnetic reflectometry are discussed in Chapter 3.
Growth Kinetics of Lipid-Based Nanodiscs to Unilamellar Vesicles: A Time-Resolved Small Angle Neutron Scattering (SANS) Study
Mixtures of dimyristoyl-phosphatidylcholine (DMPC), dimyristoyl-phosphatidylglycerol (DMPG) and dihexanoylphosphatidylcholine (DHPC) in aqueous solutions spontaneously form monodisperse, bilayered nanodiscs (also known as bicelles ) at or below the melting transition temperature of DMPC (TM ~23 C). In dilute systems above the main transition temperature TM of DMPC, bicelles coalesce (increasing their diameter) and eventually self-fold into unilamellar vesicles (ULVs). Time resolved small angle neutron scattering was used to study the growth kinetics of nanodiscs below and equal to TM over a period of hours as a function of temperature at two lipid concentrations in presence or absence of NaCl salt. Bicelles seem to undergo a sudden initial growth phase with increased temperature, which is then followed by a slower reaction-limited growth phase that depends on ionic strength, lipid concentration and temperature. The bicelle interaction energy was derived from the colloidal theory of Derjaguin and Landau, and Verwey and Overbeek (DLVO). While the calculated total energy between discs is attractive and proportional to their growth rate, a more detailed mechanism is proposed to describe the mechanism of disc coalescence. After annealing at low temperature (low-T), samples were heated to 50 C in order to promote the formation of ULVs. Although the low-T annealing of samples has only a marginal effect on the mean size of end-state ULVs, it does affect their polydispersity, which increases with increased T, presumably driven by the entropy of the system.
Mahabir, Suanne [University of Western Ontario, The; Small, Darcy [University of Western Ontario, The; Li, Ming [University of Connecticut, Storrs; Wan, Wankei [University of Western Ontario, The; Kucerka, Norbert [Canadian Neutron Beam Centre and Comelius University (Slovakia); Littrell, Ken [ORNL; Katsaras, John [ORNL; Nieh, Mu-Ping [University of Connecticut, Storrs
Neutron Scattering Conference Archive
Conference Archive Conference Archive A new portal for neutron scattering has just been established at neutronsources.org. The information contained here in the Neutron Scattering Web has been transferred to the new site. We will leave the current content here for archival purposes but no new content will be added. We encourage everyone interested in neutron scattering to take full advantage of this exciting new resource for our community. Neutronsources.org 2000 | 2001 | 2002 | 2003 | 2004 | 2005 | 2006 | 2007 | 2008 | 2009 | 2010 | 2011 | 2012 2000 June 12-14, 2000 Workshop on "New Opportunities for Better User Group Software (NOBUGS III)" Location Daresbury Laboratory, Cheshire, UK Contact Mark Enderby, Daresbury Laboratory Email email@example.com URL http://nobugs.dl.ac.uk/
Highlights from Research Conducted at Bio-SANS | ORNL Neutron...
Highlights from Research Conducted at Bio-SANS Neutrons help shed light on critical protein activity that protects our DNA New detector array improves neutron count capability at...
New detector array improves neutron count capability at HFIR's Bio-SANS |
Bio-SANS neutron count capability improves Bio-SANS neutron count capability improves New detector array improves neutron count capability at HFIR's Bio-SANS Agatha Bardoel - June 29, 2012 Bio-SANS team that worked on installation of the new detector system. Front row, left to right: Doug Selby, Steve Hicks, Shuo Qian, Sai Venkatesh Pingali, Kathy Bailey, Amy Black Jones, and Derrick Williams. Back row, left to right: Ed Blackburn, John Palatinus, William Brad O'Dell, Mike Humphreys, Justin Beal, Ken Littrell, Greg Jones, Kevin Berry, Volker Urban, Randy Summers, and Ron Maples. Bio-SANS, the Biological Small-Angle Neutron Scattering Instrument at HFIR recently had a detector upgrade that will provide significantly improved performance that is more in line with the instrument's capability. Shorter experiment times are expected, which means more experiments can be
NXS 2010 - Neutron Scattering School
2-26, 2010 2-26, 2010 Argonne National Laboratory, Argonne, IL Oak Ridge National Laboratory, Oak Ridge, TN NXS2010 Travel Airport Shuttles Departure Flights Schedule Participants Lectures Lecturers Lecture Notes/Videos Experiments Schedule, Desc, Groups Student Presentations ANL Facilities APS Facility ANL Map ANL Visitor's Guide ORNL Facilities HFIR Facility SNS Facility HFIR/SNS Map Access Requirements ANL ORNL Rad Worker Training Study Guide Wireless Networks ANL ORNL Safety & Security Rules ANL ORNL NSSA New Initiatives NSSA Weblink Contacts ANL ORNL 12th National School on Neutron & X-ray Scattering 2009 Neutron Scattering School participants 2010 National School Participants Students share their thoughts about NXS 2010. Purpose: The main purpose of the National School on Neutron and X-ray Scattering is to educate graduate students on the utilization of major neutron and x-ray facilities. Lectures, presented by researchers from academia, industry, and national laboratories, will include basic tutorials on the principles of scattering theory and the characteristics of the sources, as well as seminars on the application of scattering methods to a variety of scientific subjects. Students will conduct four short experiments at Argonne's Advanced Photon Source and Oak Ridge's Spallation Neutron Source and High Flux Isotope Reactor facilities to provide hands-on experience for using neutron and synchrotron sources.
Neutron Scattering Facilities
Gaithersburg, Maryland, USA Peruvian Institute of Nuclear Energy (IPEN), Lima, Peru Spallation Neutron Source, Oak Ridge National Laboratory, Tennessee, USA University of...
History of EQ-SANS | ORNL Neutron Sciences
History of EQ-SANS On December 23, 2008, EQ-SANS received its first neutrons. participants in the commissioning of EQ-SQNS Among those present for the start-up were (left to right)...
Neutron Scatter Camera for Radiaton Detection - Energy ...
Patent 7,741,613: Neutron scatter camera An instrument that will directly image the fast fission neutrons from a special nuclear material source has ...
NXS 2013 - Neutron Scattering School
5th National School on Neutron and X-Ray Scattering 5th National School on Neutron and X-Ray Scattering August 10-24, 2013 Argonne National Laboratory, Argonne, IL Oak Ridge National Laboratory, Oak Ridge, TN NXS2013 Schedule Participants Image Gallery Travel Info Thank you Lectures Lecture Notes/Videos Experiments ANL Facilities ANL Map (jpg) ANL Map (pdf) ANL Visitor's Guide ORNL Facilities HFIR Facility SNS Facility HFIR/SNS Map Wireless Networks ORNL Safety & Security Rules ORNL NSSA Weblink Contacts ANL ORNL 2013 NXS School Participants 2013 NXS Participants. NXS interveiws 2013 Click the image to download the video. Video Interviews: Participants answer questions about their experiences at NXS 2011. Your feedback about lectures and experiments is important for evaluating this year's Neutron and X-ray Scattering School and for making improvements for future participants. We sincerely hope that each of you will complete the survey by the end of the school.
Neutron Scattering Science User ...
Proposals for beam time at Oak Ridge National Laboratory's High Flux Isotope Reactor (HFIR) and Spallation Neutron Source (SNS) will be accepted via the web-based proposal system...
Neutron Scattering Home Page (Low-Graphics)
Home Page A new portal for neutron scattering has just been established at neutronsources.org. The information contained here in the Neutron Scattering Web has been transferred to...
LANSCE | Lujan Neutron Scattering Center
Department of Energy, National Office of Science Department of Energy, National Office of Science science.energy.gov Department of Energy, National Nuclear Security Administration nnsa.energy.gov Lujan Neutron Scattering Center Logo Lujan Center Mission The Lujan Center delivers science by exploiting the unique characteristics of intense beams of pulsed neutrons for academia, national security, and industry. Lujan Center Vision The Lujan Center will operate a world class user program in the service of the nation. Lujan Center scientists will be recognized for their leadership and innovation in neutron scattering. Lujan Center at LANSCE The Lujan Center is one of five user facilities supported by the LANSCE accelerator which is stewarded. Funding to operate 10 instruments in a national user program is provided by the Department of Energy's Office of
Geek-Up[1.28.2011]: Neutron Scattering and Full-Spectrum Solar Cells |
Energy.gov (U.S. Department of Energy (DOE)) Indexed Site
.28.2011]: Neutron Scattering and Full-Spectrum Solar .28.2011]: Neutron Scattering and Full-Spectrum Solar Cells Geek-Up[1.28.2011]: Neutron Scattering and Full-Spectrum Solar Cells January 28, 2011 - 5:11pm Addthis Detector tanks for the new SANS instruments at the High Flux Isotope Reactor. The Bio-SANS detector is on the right. Source: ORNL Detector tanks for the new SANS instruments at the High Flux Isotope Reactor. The Bio-SANS detector is on the right. Source: ORNL Niketa Kumar Niketa Kumar Public Affairs Specialist, Office of Public Affairs Oak Ridge National Lab and North Carolina State University scientists are helping to develop medicines that will block the spread of viruses. Using the Bio-SANS instrument at ORNL's High Flux Isotope Reactor, these researchers are studying how viruses change their structure as they move
SANS Publications - 2009
... 11, Characterization of the CO2 fluid adsorption in coal as a function of pressure using neutron scattering techniques (SANS and USANS), YB ...
American Conference on Neutron Scattering 2010 - ORNL Neutron...
Update on Sample Environment Plenary Session: Thom Mason: Neutron Scattering and Energy ACNS website with Program Back to Top an error occurred while processing this directive...
ORNL Neutron Scattering User Meeting (ONSUM 2011)
and learning about the capabilities of neutron scattering instruments at SNS and HFIR Meeting fellow user scientists and engineers to discuss ongoing research and R&D needs...
International Neutron Scattering Instrumentation School (INSIS...
INSIS 2012 International Neutron Scattering Instrumentation School (INSIS) 15 - 27 July, 2012 INSIS 2012 INFN - Laboratori Nazionali di Frascati * Rome, Italy About the School How...
Characterization of photosynthetic supramolecular assemblies using small angle neutron scattering
DOE Green Energy (OSTI)
We are using small angle neutron scattering (SANS) to resolve structural features of supramolecular assemblies of photosynthetic proteins in liquid and frozen solutions. SANS resolves the size, shape, and structural homogeneity of macromolecular assemblies in samples identical to those used for spectroscopic assays of photosynthetic function. Likely molecular structures of the supramolecular assemblies can be identified by comparing experimental scattering data with scattering profiles calculated for model supramolecular assemblies built from crystal structures of the individual proteins. SANS studies of the Rhodobacter sphaeroides reaction center, RC, presented here, show that the detergent solubilized RC exists in a variety of monomeric and aggregation states. The distribution between monomer and aggregate was found to depend strongly upon detergent, temperature and nature of additives, such as ethylene glycol used for low temperature spectroscopy and polyethylene glycol used for crystallization. Likely aggregate structures are being identified by fitting the experimental scattering profiles with those calculated for model aggregates built-up using the RC crystal structure. This work establishes the foundation for using SANS to identify intermediates in the RC crystallization pathways, and for determining likely structures of complexes formed between the RC and its physiological reaction partners, cytochrome c, and the LHI antenna complex.
Tiede, D.M.; Marone, P.; Wagner, A.M.; Thiyagarajan, P.
Workshop on Neutron Scattering Applications in Structural Biology...
Workshop on Neutron Scattering Applications in Structural Biology Workshop on Neutron Scattering Applications in Structural Biology For the fourth consecutive year, NScD and JINS...
Phonon Studies with Inelastic Neutron Scattering and First ...
Presentation Title, Phonon Studies with Inelastic Neutron Scattering and .... by Asynchronous In-Situ Neutron Diffraction at the Spallation Neutron Source.
Publications from Research Conducted at GP-SANS | ORNL Neutron Sciences
Publications from Research Conducted at GP-SANS Publications from Research Conducted at GP-SANS 2013 Publications Anovitz L. M., Cole D. R., Rother G., Allard L. F., Jackson A. J., Littrell K. C., "Diagenetic changes in macro- to nano-scale porosity in the St. Peter sandstone: an (ultra) small angle neutron scattering and backscattered electron imaging analysis", Geochimica et Cosmochimica Acta 102, 280-305 (2013). Black S. B., Chang Y., Bae C., Hickner M. A., "FTIR characterization of water-polymer interactions in superacid polymers", Journal of Physical Chemistry B 117, 16266-16274 (2013). Boukhalfa S., He L., Melnichenko Y. B., Yushin G., "Small-angle neutron scattering for in situ probing of ion adsorption inside micropores", Angewandte Chemie International Edition 52, 4618-4622 (2013).
NIST CNR SANS NG7 30 Meter SANS Instrument
... 7, Characterization of the CO2 fluid adsorption in coal as a function of pressure using neutron scattering techniques (SANS and USANS), YB ...
In a concerted effort supported by the National Science Foundation, the Department of Commerce, and the Department of Energy, the United States is rebuilding its leadership in neutron scattering capability through a significant investment in U.S. neutron scattering user facilities and related instrumentation. These unique facilities provide opportunities in neutron scattering to a broad community of researchers from academic institutions, federal laboratories, and industry. However, neutron scattering is often considered to be a tool for 'experts only' and in order for the U.S. research community to take full advantage of these new and powerful tools, a comprehensive education and outreach program must be developed. The workshop described below is the first step in developing a national program that takes full advantage of modern education methods and leverages the existing educational capacity at universities and national facilities. During March 27-28, 2008, a workshop entitled 'Building a Network for Neutron Scattering Education' was held in Washington, D.C. The goal of the workshop was to define and design a roadmap for a comprehensive neutron scattering education program in the United States. Successful implementation of the roadmap will maximize the national intellectual capital in neutron sciences and will increase the sophistication of research questions addressed by neutron scattering at the nation's forefront facilities. (See Appendix A for the list of attendees, Appendix B for the workshop agenda, Appendix C for a list of references. Appendix D contains the results of a survey given at the workshop; Appendix E contains summaries of the contributed talks.) The workshop brought together U.S. academicians, representatives from neutron sources, scientists who have developed nontraditional educational programs, educational specialists, and managers from government agencies to create a national structure for providing ongoing neutron scattering education. A concerted effort was made to involve representatives from historically black colleges and universities (HBCUs) and minority educational institutions (MEIs). The roadmap contained herein provides the path to a national infrastructure for education of students, faculty, and professional researchers who wish to make use of national neutron scattering facilities but do not have (or do not believe they have) the educational background to do so. Education of other stakeholders, including the public, students in kindergarten through twelfth grade (K-12), and policy makers is also included. The opening sessions of the workshop provided the current status of neutron scattering education in North America, Europe, and Australia. National neutron sources have individually developed outreach and advertising programs aimed at increasing awareness among researchers of the potential applications of neutron scattering. However, because their principal mission is to carry out scientific research, their outreach efforts are necessarily self-limiting. The opening session was designed to build awareness that the individual programs need to be coupled with, and integrated into, a broader education program that addresses the complete range of experience, from the student to the experienced researcher, and the wide range of scientific disciplines covered by neutron scattering. Such a program must also take full advantage of existing educational programs and expertise at universities and expand them using modern distance learning capabilities, recognizing that the landscape of education is changing.
Pynn, Roger [ORNL; Baker, Shenda Mary [ORNL; Louca, Despo A [ORNL; McGreevy, Robert L [ORNL; Ekkebus, Allen E [ORNL; Kszos, Lynn A [ORNL; Anderson, Ian S [ORNL
Small-Angle Neutron Scattering Studies of a-Si:H and a-Si:D
The heterogeneity of hydrogen and deuterium on the nanometer scale has been probed by samll-angle neutron scattering (SANS) from a-Si:H and a-Si:D films. Films were depsoited by two techniques, plasma-enhanced chemical vapor deposition (PECVD) and hot-wire chemical vapor deposition (HWCVD) using conditions that yield high quality films and devices.
Williamson, D. L.; Marr, D. W. M.; Nelson, B. P.; Iwaniczko, E.; Yang, J.; Yan, B.; Guha, S.
The General-Purpose Small-Angle Neutron Scattering Diffractometer at HFIR -
General-Purpose Small-Angle Neutron Scattering Diffractometer at HFIR General-Purpose Small-Angle Neutron Scattering Diffractometer at HFIR Instrument scientist Ken Littrell at GP-SANS. Instrument scientist Ken Littrell at GP-SANS. The General-Purpose Small-Angle Neutron Scattering Diffractometer (GP-SANS) instrument is optimized for providing information about structure and interactions in materials in the size range of 0.5 - 200 nm. It has a cold neutron flux on sample and capabilities comparable to those of the best SANS instruments worldwide, including a wide range of neutron wavelengths λ 5 - 30 Å, resolution Δλ ⁄ λ 9=45%, and a 1m2 area detector with 5 × 5mm2 pixel resolution with a maximum counting capability of up to 2.5 kHz. The sample-to-detector distance can be varied from 1 to 20 m, and the detector can be offset horizontally by up to 45 cm, allowing
Publications from Research Conducted at EQ-SANS | ORNL Neutron Sciences
Publications from Research Conducted at EQ-SANS Publications from Research Conducted at EQ-SANS 2013 Publications Banuelos J. L., Feng G., Fulvio P. F., Li S., Rother G., Dai S., Cummings P. T., Wesolowski D. J., "Densification of ionic liquid molecules within a hierarchical nanoporous carbon structure revealed by small angle scattering and molecular dynamics simulation", Chemistry of Materials , (2013). Choi I., Malak S. T., Xu W., Heller W. T., Tsitsilianis C., Tsukruk V. V., "Multicompartmental microcapsules from star copolymer micelles", Macromolecules 46, 1425-1436 (2013). Do C., Chen W.-R., Hong K., Smith G. S., "Equilibrium structure of a triblock copolymer system revealed by mesoscale simulation and neutron scattering", Physica B: Condensed Matter 430, 87-94 (2013).
Introduction to the EQ-SANS Workshop (EQSANS 2011)
Summary Purpose Schedule Important Dates Application Form Contact Information EQ-SANS at SNS filler Workshop Summary The EQ-SANS is the newest small-angle neutron scattering (SANS)...
Industrial Applications at Small Angle Neutron Scattering and ...
... at Small Angle Neutron Scattering and Neutron Diffraction of HANARO Reactor .... Structure/Microstructure Analysis of Faulted and Modular Materials from�...
Neutron Sciences - Neutron Scattering Dynamics in Polymer Family
Neutron scattering characterizes dynamics in polymer family Neutron scattering characterizes dynamics in polymer family Research Contact: Christine Gerstl December 2012, Written by Agatha Bardoel Understanding the interplay between structure and dynamics is the key to obtaining tailor-made materials. In the last few years, a large effort has been devoted to characterizing and relating the structure and dynamic properties in families of polymers with alkyl side groups. Now researchers have used quasielastic neutron scattering to investigate the hydrogen dynamics in poly(alkylene oxide)s with different side-chain lengths at temperatures below, as well as above, the glass transition. The combination of techniques and instruments used is bringing a more complete understanding of multiple contributions to system dynamics. The results
Application of neutron scattering to biological and hydrogen ...
... Application of neutron scattering to biological and hydrogen storage materials. Yun Liu, NCNR, NIST. This talk covers two ...
Attosecond neutron Compton scattering from protons
The effect of "anomalous" scattering of neutrons and electrons from protons in the electron-volt energy-transfer range is considered, and related experimental results are mentioned. A recent independent confirmation of this effect with a new data analysis procedure is presented. Due to the very short characteristic scattering time, there is no well defined separation of time scales of electronic and protonic motions. An outline of a proposed theoretical interpretation is presented, which is based on the fact that scattering protons represent \\textit{open} quantum systems, thus being subject to decoherence.
C. Aris Chatzidimitriou-Dreismann
Neutron Scattering Experiment Automation with Python
The Spallation Neutron Source (SNS) at Oak Ridge National Laboratory currently holds the Guinness World Record as the world most powerful pulsed spallation neutron source. Neutrons scattered off atomic nuclei in a sample yield important information about the position, motions, and magnetic properties of atoms in materials. A neutron scattering experiment usually involves sample environment control (temperature, pressure, etc.), mechanical alignment (slits, sample and detector position), magnetic field controllers, neutron velocity selection (choppers) and neutron detectors. The SNS Data Acquisition System (DAS) consists of real-time sub-system (detector read-out with custom electronics, chopper interface), data preprocessing (soft real-time) and a cluster of control and ancillary PCs. The real-time system runs FPGA firmware and programs running on PCs (C++, LabView) typically perform one task such as motor control and communicate via TCP/IP networks. PyDas is a set of Python modules that are used to integrate various components of the SNS DAS system. It enables customized automation of neutron scattering experiments in a rapid and flexible manner. It provides wxPython GUIs for routine experiments as well as IPython command line scripting. Matplotlib and numpy are used for data presentation and simple analysis. We will present an overview of SNS Data Acquisition System and PyDas architectures and implementation along with the examples of use. We will also discuss plans for future development as well as the challenges that have to be met while maintaining PyDas for 20+ different scientific instruments.
Zolnierczuk, Piotr A [ORNL; Riedel, Richard A [ORNL
Characterization of the Neutron Detector Upgrade to the GP-SANS and BIO-SANS Instruments at HFIR
Over the past year, new 1 m x 1 m neutron detectors have been installed at both the General Purpose SANS (GP-SANS) and the Bio-SANS instruments at HFIR, each intended as an upgrade to provide improved high rate capability. This paper presents the results of characterization studies performed in the detector test laboratory, including position resolution, linearity and background, as well as a preliminary look at high count rate performance.
Berry, Kevin D [ORNL; Bailey, Katherine M [ORNL; Beal, Justin D [ORNL; Diawara, Yacouba [ORNL; Funk, Loren L [ORNL; Hicks, J Steve [ORNL; Jones, Amy Black [ORNL; Littrell, Ken [ORNL; Summers, Randy [ORNL; Urban, Volker S [ORNL; Vandergriff, David H [ORNL; Johnson, Nathan [GE Energy Services; Bradley, Brandon [GE Energy Services
Inelastic neutron scattering in valence fluctuation compounds
The valence fluctuation compounds are rare earth intermetallics where hybridization of the nearly-localized 4f electrons with the conduction electrons leads to incorporation of the 4f's into the itinerant states. This hybridization slows down the conduction electrons and hence gives them a heavy effective mass, justifying application of the term 'heavy Fermion' (HF) to these materials. During the project period, we grew large single crystals of several such compounds and measured their properties using both standard thermodynamic probes and state-of-the-art inelastic neutron scattering. We obtained three main results. For the intermediate valence compounds CePd{sub 3} and YbAl{sub 3}, we showed that the scattering of neutrons by the fluctuations of the 4f magnetic moment does not have the momentum dependence expected for the itinerant heavy mass state; rather, the scattering is more typical of a localized spin fluctuation. We believe that incoherent scattering localizes the excitation. For the heavy Fermion compound Ce(Ni{sub 0.935}Pd{sub 0.065}){sub 2}Ge{sub 2}, which sits at a T = 0 critical point for transformation into an antiferromagnetic (AF) phase, we showed that the scattering from the AF fluctuations does not exhibit any of the divergences that are expected at a phase transition. We speculate that alloy disorder profoundly suppresses the growth of the fluctuating AF regions, leading to short range clusters rather than regions of infinite size. Finally, we explored the applicability of key concepts used to describe the behavior of rare earth heavy Fermions to uranium based HF compounds where the 5f electrons are itinerant as opposed to localized. We found that scaling laws relating the spin fluctuation energy measured in neutron scattering to the low temperature specific heat and susceptibility are valid for the uranium compounds, once corrections are made for AF fluctuations; however, the degeneracy of the high temperature moment is smaller than expected for rare-earth-like Hund's rule behavior, essentially because the orbital moment is suppressed for itinerant 5f electrons. We also found that the standard local-moment-based theory of the temperature dependence of the specific heat, susceptibility and neutron scattering fails badly for URu{sub 2}Zn{sub 20} and UCo{sub 2}Zn{sub 20}, even though the theory is phenomenally successful for the closely related rare earth compound YbFe{sub 2}Zn{sub 20}. Both these results highlight the distinction between the itineracy of the 5f's and the localization of the 4f's. It is our hope that these results are sufficiently significant as to stimulate deeper investigation of these compounds.
Jon M Lawrence
Topology of forward scattering of neutrons from imperfect multilayers
Neutrons sent at grazing incidence on imperfect multilayers of polymers are scattered both out of and within the plane of reflection. In the latter geometry the scattered intensity is highly structured in two series of ridges, whose loci can be labeled in terms of the neutron momenta. Intersecting ridges show evidence of mode coupling. Similar topology is expected for x-ray scattering.
Felcher, G.P.; Goyette, R.J. (Argonne National Laboratory, Argonne, Illinois 60439 (United States)); Anastasiadis, S.; Russell, T.P. (IBM Almaden Research Center, San Jose, California 95120 (United States)); Foster, M.; Bates, F. (Department of Chemical Engineering, University of Minnesota, Minneapolis, Minnesota 55455 (United States))
Development of Lithium Lanthanide Borate Scintillator for Neutron Scattering Applications
We have completed the design and testing of neutron scattering instrument detectors for powder diffractometers and single crystal diffractometers. These detectors meet the performance requirements for these types of instruments at the Department of Energy Spallation Neutron Source facility.
Czirr, J.B.; McKnight, T.; Merrill, D.
ORNL study uses neutron scattering, supercomputing to demystify...
ORNL study uses neutron scattering, supercomputing to demystify forces at play in biofuel production This graphical representation of lignocellulosic biomass based on...
USANS: the Ultra-Small-Angle Neutron Scattering Instrument at...
USANS-Ultra-Small-Angle Neutron Scattering Instrument USANS is designed for the study of hierarchical structures in natural and artificial materials. It can be considered an...
NCNR NG3-SANS Instrument Schedule B. Hammouda Tel ...
... Poly(acrylic acid) in 10CB Hammouda various solvents Jun 15 3 M. Diwekar +J. Shi 4602 Small Angle Neutron DI Kline (U. Utah) Scattering (SANS ...
Research Highlights | ORNL Neutron Sciences
Polytechnic Institute used small-angle neutron scattering (SANS) at the High-Flux Isotope Reactor at Oak Ridge National Laboratory to identify these early stage aggregates in...
techniques with neutron scattering at the General-Purpose SANS instrument at the ORNL High Flux Isotope Reactor. The cell mimics were vesicles (hollow spheres) made of...
Documentation for EQ-SANS | ORNL Neutron Sciences
the usage of high-speed choppers in the future. Optical Components for the EQ-SANS Diffractometer Supplement documentation Manuals Data collection on EQ-SANS EQ-SANS Cheat Sheet...
XII SoNS School of Neutron Scattering
XII School of Neutron Scattering (SoNS) XII School of Neutron Scattering (SoNS) "Francesco Paolo Ricci" "Introduction to the theory and techniques of neutron scattering and applications to Cultural Heritage" 30 April - 9 May 2014 A Course within the International School of Solid State Physics ETTORE MAJORANA FOUNDATION AND CENTRE FOR SCIENTIFIC CULTURE, Erice (I) Application deadline: 1 st April 2014 Application is now open for the XII School of Neutron Scattering (SoNS) "Francesco Paolo Ricci": Introduction to the theory and techniques of neutron scattering and applications to Cultural Heritage. The school will be held at the ETTORE MAJORANA FOUNDATION AND CENTRE FOR SCIENTIFIC CULTURE, Erice (Sicily, I) as a specialized course within the International School of Solid State Physics (Director: Giorgio Benedek), between the 30
Scattering of Ultra Cold Neutrons on Nano-size Bubbles
Inelastic scattering of ultra cold neutrons on bubbles with the size of nanometers is considered. It is shown that neutron-bubble cross section is large and sensitive to different vibration modes of bubbles. This process could be used for study of dynamics of nano-size bubbles and for new methods of ultra cold neutron production.
Vladimir Gudkov
Deterministic Multigroup Modeling of Thermal Effect on Neutron Scattering by Heavy Nuclides.
??The principal physical phenomenon underlying the computation of neutron spectra is the nuclear reaction in which neutrons lose or gain energy, i.e., the neutron scattering� (more)
Ghrayeb, Shadi
Neutron Scattering | U.S. DOE Office of Science (SC)
Office of Science (SC) Website
Neutron Scattering Neutron Scattering Materials Sciences and Engineering (MSE) Division MSE Home About Research Areas Energy Frontier Research Centers (EFRCs) DOE Energy Innovation Hubs BES Funding Opportunities The Computational Materials and Chemical Sciences Network (CMCSN) Theoretical Condensed Matter Physics Scientific Highlights Reports and Activities Principal Investigators' Meetings BES Home Research Areas Neutron Scattering Print Text Size: A A A RSS Feeds FeedbackShare Page This activity supports basic research on the fundamental interactions of neutrons with matter to achieve an understanding of the atomic, electronic, and magnetic structures and excitations of materials and their relationship to materials properties. Major emphasis is on the application of neutron scattering, spectroscopy, and imaging for materials research, primarily at
... 4 NG-7 30 m SANS Small Angle Neutron Scattering instrument for microstructure measurement sponsored by NIST, the ExxonMobil Research ...
... 4 NG-7 30m SANS Small Angle Neutron Scattering instrument for microstructure measurement sponsored by NIST, the Exxon Research and ...
News Releases and Features | Neutron Science | ORNL
June 29, 2012 - Bio-SANS, the Biological Small-Angle Neutron Scattering Instrument at HFIR recently had a detector upgrade that will provide significantly improved performance...
Neutron beam characterization measurements at the Manuel Lujan Jr. neutron scattering center
We have measured the neutron beam characteristics of neutron moderators at the Manuel Lujan Jr. Neutron Scattering Center at LANSCE. The absolute thermal neutron flux, energy spectra and time emission spectra were measured for the high resolution and high intensity decoupled water, partially coupled liquid hydrogen and partially coupled water moderators. The results of our experimental study will provide an insight into aging of different target-moderator-reflector-shield components as well as new experimental data for benchmarking of neutron transport codes.
Mocko, Michal [Los Alamos National Laboratory; Muhrer, Guenter [Los Alamos National Laboratory; Daemen, Luke L [Los Alamos National Laboratory; Kelsey, Charles T [Los Alamos National Laboratory; Duran, Michael A [Los Alamos National Laboratory; Tovesson, Fredrik K [Los Alamos National Laboratory
Neutron-deuteron elastic scattering and three-nucleon force
The differential cross section for neutron-deuteron elastic scattering was measured at six angles over the center-of-mass angular range 65? - 1300? and incident neutron energies 140 - 240 MeV at the LANSCE/WNR facility of ...
Chtangeev, Maxim B
Measurements of the Thermal Neutron Scattering Kernel
world's most powerful neutron source, the $1.4 billion Spallation Neutron Source At 1.4MW, SNS produces. SNS will feature 24 beamlines for physics, chemistry, biology, materials research. www.sns.gov #12 · Coproduction of epithermal, thermal and cold neutrons #12;SNS Instrument Beam Lines 1st experimentproposed 2nd
Danon, Yaron
Bio-SANS Instrument Team | ORNL Neutron Sciences
Instrument Team Instrument team Bio-SANS Team (left to right): Qiu Zhang, Student Volker Urban, Lead Instrument Scientist Sai Venkatesh Pingali, Instrument Scientist Shuo Qian,...
SANS at the NIST Center for Neutron Research
... run an FTP server, but a quick search on the ... Password: Enter your sans username here. ... or unauthorized, constitutes consent to 230-these terms. ...
The 30 m Small-Angle Neutron Scattering Instruments at the ...
... The 30 m SANS instrument on neutron guide NG-7, in operation since May 1991, was developed jointly by NIST, the Exxon Research and ...
Investigating Microscopic Heat Transport with Neutron Scattering
In-Situ Neutron Diffraction and Crystal Plasticity Modeling of a-Uranium � In-Situ Studies of the ... Thermal Residual Stresses and Strains in Depleted Uranium.
Neutron Scattering Analysis of Magnetostructural Phase ...
Experiments to observe the structural and magnetic phase transformations were performed at the Spallation Neutron Source (SNS) at Oak Ridge National�...
New detector array improves neutron count capability at HFIR...
and Ron Maples. Bio-SANS, the Biological Small-Angle Neutron Scattering Instrument at HFIR recently had a detector upgrade that will provide significantly improved performance...
Initial characterization of mudstone nanoporosity with small angle neutron scattering using caprocks from carbon sequestration sites.
Geological carbon sequestration relies on the principle that CO{sub 2} injected deep into the subsurface is unable to leak to the atmosphere. Structural trapping by a relatively impermeable caprock (often mudstone such as a shale) is the main trapping mechanism that is currently relied on for the first hundreds of years. Many of the pores of the caprock are of micrometer to nanometer scale. However, the distribution, geometry and volume of porosity at these scales are poorly characterized. Differences in pore shape and size can cause variation in capillary properties and fluid transport resulting in fluid pathways with different capillary entry pressures in the same sample. Prediction of pore network properties for distinct geologic environments would result in significant advancement in our ability to model subsurface fluid flow. Specifically, prediction of fluid flow through caprocks of geologic CO{sub 2} sequestration reservoirs is a critical step in evaluating the risk of leakage to overlying aquifers. The micro- and nanoporosity was analyzed in four mudstones using small angle neutron scattering (SANS). These mudstones are caprocks of formations that are currently under study or being used for carbon sequestration projects and include the Marine Tuscaloosa Group, the Lower Tuscaloosa Group, the upper and lower shale members of the Kirtland Formation, and the Pennsylvanian Gothic shale. Total organic carbon varies from shale and Kirtland Formation, respectively. Neutrons effectively scatter from interfaces between materials with differing scattering length density (i.e. minerals and pores). The intensity of scattered neutrons, I(Q), where Q is the scattering vector, gives information about the volume of pores and their arrangement in the sample. The slope of the scattering data when plotted as log I(Q) vs. log Q provides information about the fractality or geometry of the pore network. Results from this study, combined with high-resolution TEM imaging, provide insight into the differences in volume and geometry of porosity between these various mudstones.
McCray, John (Colorado School of Mines); Navarre-Sitchler, Alexis (Colorado School of Mines); Mouzakis, Katherine (Colorado School of Mines); Heath, Jason E.; Dewers, Thomas A.; Rother, Gernot (Oak Ridge National Laboratory)
Introduction to Small-Angle Neutron Scattering and Neutron ...
... where g(r) is the pair correlation function for the scattering objects and lng(r) is directly related to the potential energy function that describes the ...
Publications from Research Conducted at Bio-SANS | ORNL Neutron...
Specifications of the Bio-SANS Instrument Wavelength: 6 < < 25 Wavelength resolution: 9- 45% Q range: 0.0009 -0.8 -1 Sample-to-detector distance: 1.1 - 15.3 m...
Neutron and X-Ray Scattering - Argonne National Laboratories, Materials
Home Home Neutron and X-Ray Scattering Neutron and X-ray Scattering Science Recent advances in neutron and x-ray scattering instrumentation at major DOE facilities such as the Spallation Neutron Source and Advanced Photon Source provide unprecedented insights into complex phenomena in bulk and interfacial materials. The vision of our group is to harness the complementarity of neutrons and x-rays to study how materials respond on a range of length and time scales to phase competition, so that we can learn to control emergent behavior and generate functional properties in energy-related materials. We use neutrons and x-rays to investigate the structure and dynamics of bulk and interfacial materials with properties that are useful for energy applications, such as superconductivity, magnetism and thermoelectricity. Phase competition can generate or enhance such properties, but it is extremely challenging to characterize fluctuations in the competing order, whether in bulk disordered materials, or artificial heterostructures. Our goal is to utilize efficient techniques that we have been developing for measuring nanoscale phase fluctuations, both static and dynamic, to enable the rational design of new materials for energy within MSD.
Pore accessibility by methane and carbon dioxide in coal as determined by neutron scattering
Contrast-matching ultrasmall-angle neutron scattering (USANS) and small-angle neutron scattering (SANS) techniques were used for the first time to determine both the total pore volume and the fraction of the pore volume that is inaccessible to deuterated methane, CD{sub 4}, in four bituminous coals in the range of pore sizes between {approx}10 {angstrom} and {approx}5 {micro}m. Two samples originated from the Illinois Basin in the U.S.A., and the other two samples were commercial Australian bituminous coals from the Bowen Basin. The total and inaccessible porosity were determined in each coal using both Porod invariant and the polydisperse spherical particle (PDSP) model analysis of the scattering data acquired from coals both in vacuum and at the pressure of CD{sub 4}, at which the scattering length density of the pore-saturating fluid is equal to that of the solid coal matrix (zero average contrast pressure). The total porosity of the coals studied ranged from 7 to 13%, and the volume of pores inaccessible to CD{sub 4} varied from {approx}13 to {approx}36% of the total pore volume. The volume fraction of inaccessible pores shows no correlation with the maceral composition; however, it increases with a decreasing total pore volume. In situ measurements of the structure of one coal saturated with CO{sub 2} and CD{sub 4} were conducted as a function of the pressure in the range of 1-400 bar. The neutron scattering intensity from small pores with radii less than 35 {angstrom} in this coal increased sharply immediately after the fluid injection for both gases, which demonstrates strong condensation and densification of the invading subcritical CO{sub 2} and supercritical methane in small pores.
He, Lilin [ORNL; Melnichenko, Yuri B [ORNL; Mastalerz, Maria [Indiana Geological Survey; Sakurovs, Richard [ORNL; Radlinski, Andrzej Pawell [ORNL; Blach, Tomasz P [ORNL
SANS for Biology William T. Heller, Ph.D.
SANS for Biology A Tutorial William T. Heller, Ph.D. SNS-HFIR Users Meeting October 10, 2007 #12 probed Detector: Collects the neutrons scattered by the sample SNS and HFIR have large area detectors #12;SANS Instruments The HFIR SANS instrument control program is based on Spice, originally developed
Neutron Form Factor from Neutrino-Nucleus Coherent Elastic Scattering
We analyze the prospect of measuring the neutron form factor of a nucleus through the detection of neutrino-nucleus coherent elastic scattering. We predict numbers of events in a liquid noble nuclear recoil detector at a stopped pion neutrino source. We discuss the precision required to distinguish between different theoretical models for the form factor.
Philip S. Amanik; Gail C. McLaughlin
A workshop on enhanced national capability for neutron scattering
This two-day workshop will engage the international neutron scattering community to vet and improve the Lujan Center Strategic Plan 2007-2013 (SP07). Sponsored by the LANL SC Program Office and the University of California, the workshop will be hosted by LANSCE Professor Sunny Sinha (UCSD). Endorsement by the Spallation Neutron Source will be requested. The discussion will focus on the role that the Lujan Center will play in the national neutron scattering landscape assuming full utilization of beamlines, a refurbished LANSCE, and a 1.4-MW SNS. Because the Lujan Strategic Plan is intended to set the stage for the Signature Facility era at LANSCE, there will be some discussion of the long-pulse spallation source at Los Alamos. Breakout groups will cover several new instrument concepts, upgrades to present instruments, expanded sample environment capabilities, and a look to the future. The workshop is in keeping with a request by BES to update the Lujan strategic plan in coordination with the SNS and the broader neutron community. Workshop invitees will be drawn from the LANSCE User Group and a broad cross section of the US, European, and Pacific Rim neutron scattering research communities.
Hurd, Alan J [Los Alamos National Laboratory; Rhyne, James J [Los Alamos National Laboratory; Lewis, Paul S [Los Alamos National Laboratory
Instrument - NG7 SANS - Small Angle Neutron Scattering
... Jointly developed and sponsored by the NCNR, the ExxonMobil Research and Engineering Co., and the University of Minnesota, the instrument ...
2009 International Conference on Neutron Scattering (ICNS 2009)
The ICNS provides a focal point for the worldwide neutron user community to strengthen ties within this diverse group, while at the same time promoting neutron research among colleagues in related disciplines identified as �?¢�?�?�?�?would-be�?¢�?�?�? neutron users. The International Conference on Neutron Scattering thus serves a dual role as an international user meeting and a scientific meeting. As a venue for scientific exchange, the ICNS showcases recent results and provides forums for scientific discussion of neutron research in diverse fields such as hard and soft condensed matter, liquids, biology, magnetism, engineering materials, chemical spectroscopy, crystal structure, and elementary excitations, fundamental physics and development of neutron instrumentation through a combination of invited talks, contributed talks and poster sessions. Each of the major national neutron facilities (NIST, LANSCE, ANL, HFIR and SNS), along with their international counterparts, has an opportunity to exchange information with each other and to update users, and potential users, of their facility. This is also an appropriate forum for users to raise issues that relate to the facilities.
Gopal Rao, PhD; Donna Gillespie
A Neutron Scattering Kernel of Solid Methane in phase II
A neutron scattering cross section model for solid methane was studied in the temperature ranges of 20.4$\\sim$4K. The analytical scattering kernel was adapted from Ozaki.$\\it{et al.}$\\cite{ozaki:3442}\\cite{ozaki2} to describe molecular rotation in this temperature range. This model includes a molecular translation and intramolecular vibration as well as the rotational degree of freedom in effective ways. Total scattering cross sections were calculated from the model and evaluated by comparing with the cross section measurement of Grieger\\cite{grieger:3161} and Whittemore\\cite{Wittemore} for incident neutron energy of 0.1 \\textit{meV} $\\sim$ 1\\textit{eV}. We produced frequency spectra from the model in the temperature range. The results were also compared with the Harker $&$ Brugger frequency spectrum at 22K\\cite{HARKER1967}. For broader applications, neutron scattering kernels for MCNP (Monte Carlo N Particle Transport Code) were produced at 20K and 4K from the frequency spectra using NJOY code. The scatt...
Shin, Yunchang; Liu, Chen-yu; Lavelle, Christopher M; Baxter, David V
Introduction to Neutron and X-Ray Scattering
Scattering Studies of Thin Scattering Studies of Thin Polymer Films Introduction to Neutron and X-Ray Scattering Sunil K. Sinha UCSD/LANL Acknowledgements: Prof. R.Pynn( Indiana U.) Prof. M.Tolan (U. Dortmund) Wilhelm Conrad Röntgen 1845-1923 1895: Discovery of X-Rays 1901 W. C. Röntgen in Physics for the discovery of x-rays. 1914 M. von Laue in Physics for x-ray diffraction from crystals. 1915 W. H. Bragg and W. L. Bragg in Physics for crystal structure determination. 1917 C. G. Barkla in Physics for characteristic radiation of elements. 1924 K. M. G. Siegbahn in Physics for x-ray spectroscopy. 1927 A. H. Compton in Physics for scattering of x-rays by electrons. 1936 P. Debye in Chemistry for diffraction of x-rays and electrons in gases.
CORELLI: the Elastic Diffuse Scattering Spectrometer at SNS | ORNL Neutron
The Elastic Diffuse Scattering Spectrometer The Elastic Diffuse Scattering Spectrometer CORELLI The CORELLI instrument. CORELLI is a statistical chopper spectrometer with energy discrimination. It's designed and optimized to probe complex disorder in crystalline materials through diffuse scattering of single-crystal samples. The momentum transfer ranges from 0.5 to 12 Å-1, and the energy of incident neutrons ranges from 10 to 200 meV. This instrument combines the high efficiency of white-beam Laue diffraction with energy discrimination by modulating the beam with a statistical chopper. A cross-correlation method is used to reconstruct the elastic signal from the modulated data. Accurate modeling of the short-range order associated with the diffuse scattering requires measurements over large volumes of three-dimensional reciprocal space, with sufficient momentum
School on Neutron and X-ray Scattering Oak Ridge 10-24 August 2013 John M. Carpenter ANL, ORNLSNS 18 August 2013 2 Neutron Detection How does one detect a neutron? - It is...
Neutrons for Catalysis: A Workshop on Neutron Scattering Techniques for Studies in Catalysis
This report summarizes the Workshop on Neutron Scattering Techniques for Studies in Catalysis, held at the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory (ORNL) on September 16 and 17, 2010. The goal of the Workshop was to bring experts in heterogeneous catalysis and biocatalysis together with neutron scattering experimenters to identify ways to attack new problems, especially Grand Challenge problems in catalysis, using neutron scattering. The Workshop locale was motivated by the neutron capabilities at ORNL, including the High Flux Isotope Reactor (HFIR) and the new and developing instrumentation at the SNS. Approximately 90 researchers met for 1 1/2 days with oral presentations and breakout sessions. Oral presentations were divided into five topical sessions aimed at a discussion of Grand Challenge problems in catalysis, dynamics studies, structure characterization, biocatalysis, and computational methods. Eleven internationally known invited experts spoke in these sessions. The Workshop was intended both to educate catalyst experts about the methods and possibilities of neutron methods and to educate the neutron community about the methods and scientific challenges in catalysis. Above all, it was intended to inspire new research ideas among the attendees. All attendees were asked to participate in one or more of three breakout sessions to share ideas and propose new experiments that could be performed using the ORNL neutron facilities. The Workshop was expected to lead to proposals for beam time at either the HFIR or the SNS; therefore, it was expected that each breakout session would identify a few experiments or proof-of-principle experiments and a leader who would pursue a proposal after the Workshop. Also, a refereed review article will be submitted to a prominent journal to present research and ideas illustrating the benefits and possibilities of neutron methods for catalysis research.
Overbury, Steven {Steve} H [ORNL; Coates, Leighton [ORNL; Herwig, Kenneth W [ORNL; Kidder, Michelle [ORNL
Neutron and Synchrotron X-Ray Scattering Studies of Superconductors
Superconductors hold the promise for a more stable and efficient electrical grid, but new isotropic, high-temperature superconductors are needed in order to reduce cable manufacturing costs. The effort to understand high-temperature superconductivity, especially in the layered cuprates, provides guidance to the search for new superconductors. Neutron scattering has long provided an important probe of the collective excitations that are involved in the pairing mechanism. For the cuprates, neutron and x-ray diffraction techniques also provide information on competing types of order, such as charge and spin stripes, that appear to be closely connected to the superconductivity. Recently, inelastic x-ray scattering has become competitive for studying phonons and may soon provide valuable information on electronic excitations. Examples of how these techniques contribute to our understanding of superconductivity are presented.
Scientific opportunities with advanced facilities for neutron scattering
The present report documents deliberations of a large group of experts in neutron scattering and fundamental physics on the need for new neutron sources of greater intensity and more sophisticated instrumentation than those currently available. An additional aspect of the Workshop was a comparison between steady-state (reactor) and pulsed (spallation) sources. The main conclusions were: (1) the case for a new higher flux neutron source is extremely strong and such a facility will lead to qualitatively new advances in condensed matter science and fundamental physics; (2) to a large extent the future needs of the scientific community could be met with either a 5 x 10/sup 15/ n cm/sup -2/s/sup -1/ steady state source or a 10/sup 17/ n cm/sup -2/s/sup -1/ peak flux spallation source; and (3) the findings of this Workshop are consistent with the recommendations of the Major Materials Facilities Committee.
Lander, G.H.; Emery, V.J. (eds.)
Neutron Scattering Facilities | U.S. DOE Office of Science (SC)
Neutron Scattering Facilities Neutron Scattering Facilities Scientific User Facilities (SUF) Division SUF Home About User Facilities X-Ray Light Sources Neutron Scattering Facilities Nanoscale Science Research Centers Electron-Beam Microcharacterization Centers Accelerator & Detector Research & Development Principal Investigators' Meetings Scientific Highlights Construction Projects BES Home User Facilities Neutron Scattering Facilities Print Text Size: A A A RSS Feeds FeedbackShare Page This activity supports the operation of three DOE neutron scattering facilities, which are unique and effective tools for probing the structure of matter. Neutron scattering is particularly well-suited for determining the atomic positions of both light and heavy atoms in a solid and thermal fluctuations in these positions. In addition the neutron
Clifford G. Shull: A Memoir of a Pioneer in Neutron Scattering
Clifford G. Shull: A Memoir of a Pioneer in Neutron Scattering. ... The memoir is a history, a love story, and an allegory on how to practice science. ...
Instruments | Neutron Science | ORNL
NScD Careers NScD Careers Supporting Organizations Neutron Science Home | Science & Discovery | Neutron Science | Instruments SHARE Instruments at SNS and HFIR SNS Instrument Name HFIR Instrument Name 1B NOMAD - Nanoscale-Ordered Materials Diffractometer CG-1 Development Beam Line 2 BASIS - Backscattering Spectrometer CG-1D IMAGING - Neutron Imaging Prototype Facility 3 SNAP - Spallation Neutrons and Pressure Diffractometer CG-2 GP-SANS - General-Purpose Small-Angle Neutron Scattering Diffractometer 4A MR - Magnetism Reflectometer CG-3 Bio-SANS - Biological Small-Angle Neutron Scattering Instrument 4B LR - Liquids Reflectometer CG-4C CTAX - Cold Neutron Triple-Axis Spectrometer 5 CNCS - Cold Neutron Chopper Spectrometer HB-1 PTAX - Polarized Triple-Axis Spectrometer
Digenetic Changes in Macro- to Nano-Scale Porosity in the St. Peter Sandstone:L An (Ultra) Small Angle Neutron Scattering and Backscattered Electron Imagining Analysis
Small- and Ultra-Small Angle Neutron Scattering (SANS and USANS) provide powerful tools for quantitative analysis of porous rocks, yielding bulk statistical information over a wide range of length scales. This study utilized (U)SANS to characterize shallowly buried quartz arenites from the St. Peter Sandstone. Backscattered electron imaging was also used to extend the data to larger scales. These samples contain significant volumes of large-scale porosity, modified by quartz overgrowths, and neutron scattering results show significant sub-micron porosity. While previous scattering data from sandstones suggest scattering is dominated by surface fractal behavior over many orders of magnitude, careful analysis of our data shows both fractal and pseudo-fractal behavior. The scattering curves are composed of subtle steps, modeled as polydispersed assemblages of pores with log-normal distributions. However, in some samples an additional surface-fractal overprint is present, while in others there is no such structure, and scattering can be explained by summation of non-fractal structures. Combined with our work on other rock-types, these data suggest that microporosity is more prevalent, and may play a much more important role than previously thought in fluid/rock interactions.
Anovitz, Lawrence {Larry} M [ORNL; Cole, David [Ohio State University; Rother, Gernot [ORNL; Allard Jr, Lawrence Frederick [ORNL; Jackson, Andrew [NIST Center for Neutron Research (NCRN), Gaithersburg, MD; Littrell, Ken [ORNL
Calibration of neutron-yield diagnostics in attenuating and scattering environments
We have performed absolute calibrations of a fusion-neutron-yield copper-activation diagnostic in environments that significantly attenuate and scatter neutrons. We have measured attenuation and scattering effects and have compared the measurements to Monte Carlo simulations using the Monte Carlo N-Particle code. We find that measurements and simulations are consistent within 10%.
Hahn, K. D.; Ruiz, C. L.; Chandler, G. A.; Leeper, R. J.; McWatters, B. R.; Smelser, R. M.; Torres, J. A. [Sandia National Laboratories, Diagnostics and Target Physics, Albuquerque, New Mexico 87111 (United States); Cooper, G. W.; Nelson, A. J. [University of New Mexico, Department of Chemical and Nuclear Engineering, Albuquerque, New Mexico 87131 (United States)
Dr. Yuri B. Melnichenko | ORNL Neutron Sciences
Scientist: General-Purpose Small-Angle Neutron Scattering Spectrometer (CG-2GP-SANS), HFIR Senior Research Staff Education PhD in Polymer Physics, Institute for Macromolecular...
Naysaying the Neutron Scattering Society Lawrence Cranberg, Jill Trewhella, and Henry R. Glyde
The New Munich Neutron Source FRM II: Overview and Uses for Biological Studies Wolfgang Doster Technical University Munich, Physics Department E 13, D-85748 Garching, Email: firstname.lastname@example.com Abstract. The application of neutron scattering to biological systems using the new neutron source in Munich is discussed
Glyde, Henry R.
A brief History of Neutron Scattering at the Oak Ridge High Flux Isotope Reactor
Neutron scattering at the Oak Ridge National Laboratory dates back to 1945 when Ernest Wollan installed a modified x-ray diffractometer on a beam port of the original graphite reactor. Subsequently, Wollan and Clifford Shull pioneered neutron diffraction and laid the foundation for an active neutron scattering effort that continued through the 1950s, using the Oak Ridge Research reactor after 1958, and, starting in 1966, the High Flux Isotope Reactor, or HFIR.
Nagler, Stephen E [ORNL; Mook Jr, Herbert A [ORNL
Neutron scattering analysis with microscopic optical model potentials
A review of microscopic optical model potentials used in the analysis of neutron scattering and analyzing power data below 100 MeV (5 {le}E{sub n}{le}100 MeV) is presented. The quality of the fits to the data over a wide massd ({sup 6}Li-{sup 239}Pu) and energy range is discussed. It is shown that reasonably good agreement with the data is obtained with only three parameters, {lambda}{sub V}, {lambda}{sub W}, and {lambda}{sub SO}, which show a smooth mass and energy dependence. These parameters are normalizing constants to the real (V), and imaginary (W) central potentials and the real spin-orbit (V{sub SO}) potential. 14 refs., 7 figs.
Hansen, L.F.
Thirteenth National School on Neutron and X-ray Scattering
Spallation-Driven Cold Neutron Sources Dr. Bradley J. Micklich Senior Physicist, Physics Division physics research Want neutron wavelengths about the dimensions of interest, or neutron energies that can using an intense source of longerwavelength neutrons fundamental nuclear physics (neutron halflife
In-Situ Observation of Solid Electrolyte Interphase Formation in Ordered Mesoporous Hard Carbon by Small-Angle Neutron Scattering
The aim of this work was to better understand the electrochemical processes occurring during the cycling of a lithium-ion half-cell containing ordered mesoporous hard carbon using time-resolved in situ small-angle neutron scattering (SANS). Utilizing electrolytes containing mixtures of deuterated (2H) and non-deuterated (1H) carbonates, we have addressed the challenging task of monitoring the formation and evolution of the solid-electrolyte interphase (SEI) layer. An evolution occurs in the SEI layer during discharge from a composition dominated by a higher scattering length density (SLD) lithium salt, to a lower SLD lithium salt for the ethylene carbonate/dimethyl carbonate (EC/DMC) mixture employed. By comparing half-cells containing different solvent deuteration levels, we show that it is possible to observe both SEI formation and lithium intercalation occurring concurrently at the low voltage region in which lithium intercalates into the hard carbon. These results demonstrate that SANS can be employed to monitor complicated electrochemical processes occurring in rechargeable batteries, in a manner that simultaneously provides information on the composition and microstructure of the electrode.
Bridges, Craig A [ORNL; Paranthaman, Mariappan Parans [ORNL; Sun, Xiao-Guang [ORNL; Zhao, Jinkui [ORNL; Dai, Sheng [ORNL
Applied Neutron Scattering in Engineering and Materials Science ...
Neutron Diffraction Studies of Residual Stresses around Gouges and Gouged Dents in Pipelines � Neutron Diffraction Study and EVPSC Modeling of the�...
Directional Stand-off Detection of Fast Neutrons and Gammas Using Angular Scattering Distributions
We have investigated the response of a DoubleScatter Neutron Spectrometer (DSNS) for sources at long distances (gr than 200 meters). We find that an alternative method for analyzing double scatter data avoids some uncertainties introduced by amplitude measurements in plastic scintillators.Time of flight is used to discriminate between gamma and neutron events, and the kinematic distributions of scattering angles are assumed to apply. Non-relativistic neutrons are most likely to scatter at 45�, while gammas with energies greater than 2 MeV are most likely to be forward scattered. The distribution of scattering angles of fission neutrons arriving from a distant point source generates a 45� cone, which can be back-projected to give the source direction. At the same time, the distribution of Compton-scattered gammas has a maximum in the forward direction, and can be made narrower by selecting events that deposit minimal energy in the first scattering event. We have further determined that the shape of spontaneous fission neutron spectra at ranges gr than 110 m is still significantly different from thecosmic ray background.
Vanier P. e.; Dioszegi, I.; Salwen, C.; Forman, L.
Corrections on energy spectrum and scatterings for fast neutron radiography at NECTAR facility
Neutron spectrum and scattered neutrons caused distortions are major problems in fast neutron radiography and should be considered for improving the image quality. This paper puts emphasis on the removal of these image distortions and deviations for fast neutron radiography performed at the NECTAR facility of the research reactor FRM-II in Technische Universit\\"at M\\"unchen (TUM), Germany. The NECTAR energy spectrum is analyzed and established to modify the influence caused by neutron spectrum, as well as the Point Scattered Function (PScF) simulated by the Monte-Carlo program MCNPX is used to evaluate scattering effects from the object and improve images qualities. Good analysis results prove the sounded effects of above two corrections.
Shu-Quan, Liu; Hang, Li; Yu-Bin, Zou; Yuan-Rong, Lu; Zhi-Yu, Guo
Workshop For Analyzing SANS Data
HFIR Center for Neutron Scattering HFIR Center for Neutron Scattering Workshop for Analyzing SANS Data April 18 - 20, 2011 SNS Logo Spallation Neutron Source * Oak Ridge National Laboratory * Oak Ridge TN, USA Workshop Home Workshop Agenda Information Contacts Pre-Workshop Installation & Reading filler Workshop summary and purpose Since its inception the BIO-SANS and GP-SANS instruments have supported over 440 unique users and thus a need arose to supply users with additional support via data analysis and reduction to expedite the publication of new science. A continuation of this kind of user support is being done by our upcoming workshop to help past users reduce and analyze data from our SANS instruments using the established data acquisition software. We will be using Igor Pro and our in house routines to do the data reduction and fitting. The goal is that everyone who attends will leave the workshop with completely analyzed data and meaningful results. To accomplish this feat, we will focus the first day on data reduction and the following two days on analysis. We will go over in detail all the different fitting functions that are currently supported in Igor and set-aside time to discuss what other functions need to be inputted into Igor. Finally, there will be a demonstration of the new NSSD data reduction/analysis software, MANTID, that will be implemented in the near future across the SANS beam lines.
The Manuel Lujan, Jr. Neutron Scattering Center LANSCE experiment reports 1989 run cycle
This report contains a listing and description of experiments carried on at the LANSCE neutron scattering facility in the following areas: High Density Powder Diffraction; Neutron Powder Diffractometer, (NPD); Single Crystal Diffractometer, (SCD); Low-Q Diffractometer, (LQD); Surface Profile Analysis Reflectometer, (SPEAR); Filter Difference Spectrometer, (FDS); and Constant-Q Spectrometer.
Hyer, D.K.; DiStravolo, M.A. (comps.)
A slow-neutron-transmission method fro dertermining the hydrogen content of fluorcarbons is described (G.Y.).
Rainwater, L.J.; Havens, W.W. Jr.
Improved Technique of Hydrogen Content Analysis by Slow Neutron Scattering
DOE R&D Accomplishments (OSTI)
A slow-neutron-transmission method fro determining the H content of fluorcarbons is described (G.Y.)
Rainwater, L. J.; Havens, W. W. Jr.
2011 U.S. National School on Neutron and X-ray Scattering
The 13th annual U.S. National School on Neutron and X-ray Scattering was held June 11 to 25, 2011, at both Oak Ridge and Argonne National Laboratories. This school brought together 65 early career graduate students from 56 different universities in the US and provided them with a broad introduction to the techniques available at the major large-scale neutron and synchrotron x-ray facilities. This school is focused primarily on techniques relevant to the physical sciences, but also touches on cross-disciplinary bio-related scattering measurements. During the school, students received lectures by over 30 researchers from academia, industry, and national laboratories and participated in a number of short demonstration experiments at Argonne's Advanced Photon Source (APS) and Oak Ridge's Spallation neutron Source (SNS) and High Flux Isotope Reactor (HFIR) facilities to get hands-on experience in using neutron and synchrotron sources. The first week of this year's school was held at Oak Ridge National Lab, where Lab director Thom Mason welcomed the students and provided a shitorical perspective of the neutron and x-ray facilities both at Oak Ridge and Argonne. The first few days of the school were dedicated to lectures laying out the basics of scattering theory and the differences and complementarity between the neutron and x-ray probes given by Sunil Sinha. Jack Carpenter provided an introduction into how neutrons are generated and detected. After this basic introduction, the students received lectures each morning on specific techniques and conducted demonstration experiments each afternoon on one of 15 different instruments at either the SNS or HFIR. Some of the topics covered during this week of the school included inelastic neutron scattering by Bruce Gaulin, x-ray and neutron reflectivity by Chuck Majkrazak, small-angle scattering by Volker Urban, powder diffraction by Ashfia Huq and diffuse scattering by Gene Ice.
Lang, Jonathan [Argonne National Laboratory (ANL); te Vethuis, Suzanne [Argonne National Laboratory (ANL); Ekkebus, Allen E [ORNL; Chakoumakos, Bryan C [ORNL; Budai, John D [ORNL
Fourteenth National School on Neutron and X-ray Scattering
either nuclear physics parameters such as the effective delayed neutron fraction, or the so- called several new features in the physics of the ADS that require further development of the theory of neutron / q 3.784= #12;Neutron Fluctuations in Reactors R111 The physical reason for the above
Pennycook, Steve
National School on Neutron and X-ray Scattering
Cooling of isolated neutron stars as a probe of superdense matter physics Alexander Kaminker physics Alexander Kaminker 1. Introduction Microscopic theories of superdense matter in neutron star cores #12;Cooling of isolated neutron stars as a probe of superdense matter physics Alexander Kaminker
Neutron Scattering Society of America Purpose and New Initiatives
's personal copy Dosimetry and spectrometry at accelerator based neutron source for boron neutron capture Institute of Nuclear Physics, 11 Lavrentiev Ave., 630090 Novosibirsk, Russia Federation a r t i c l e i n f Keywords: Epithermal neutrons Accelerator Time-of-flight technique a b s t r a c t An innovative
Design Analyses and Shielding of HFIR Cold Neutron Scattering Instruments
Research reactor geometries and special characteristics present unique dosimetry analysis and measurement issues. The introduction of a cold neutron moderator and the production of cold neutron beams at the Oak Ridge National Laboratory High Flux Isotope Reactor have created the need for modified methods and devices for analyzing and measuring low energy neutron fields (0.01 to 100 meV). These methods include modifications to an MCNPX version to provide modeling of neutron mirror reflection capability. This code has been used to analyze the HFIR cold neutron beams and to design new instrument equipment that will use the beams. Calculations have been compared with time-of-flight measurements performed at the start of the neutron guides and at the end of one of the guides. The results indicate that we have a good tool for analyzing the transport of these low energy beams through neutron mirror and guide systems for distance up to 60 meters from the reactor. (authors)
Gallmeier, F.X.; Selby, D.L.; Winn, B.; Stoica, D.; Jones, A.B.; Crow, L. [Neutron Sciences Directorate, Oak Ridge National Laboratory (United States)
Neutron scattering study of MnSi proving no exchange hole
Neutron scattering experiments have been performed in MnSi below T/sub c/ with the double-axis powder scattering technique using unpolarized neutrons, and also with the polarization analysis technique. The magnetic scattering intensity has not shown any anomaly around q = 0.5 A/sup -1/, in contrast to the previous results of Ziebeck et al. who found a large intensity peak at this momentum transfer. Thus the hypothesis of Ziebeck et al. of observing an Exchange Hole is excluded.
Uemura, Y.J.; Majkrzak, C.F.; Shirane, G.; Ishikawa, Y.
Neutron Scattering Studies of Fundamental Processes in Earth Materials, Final Report
The aim of this work was to use neutron scattering techniques to explore the dynamics and structure of water in rock samples. The dynamics of water in rock at low (residual) saturation are directly related to the transport properties of fluids within the host rock. The structure of water in rock may be related to the elastic behavior of the rock, which in many cases is nonlinear and hysteretic. Neutron scattering techniques allow us to study water in intact rock samples at both the molecular and microstructural scales. Our samples were Berea sandstone, Calico Hills and Prow Pass tuffs from Yucca Mountain, NV, and pure samples of the tuff constituents, specifically mordenite and clinoptilolite. We chose Berea sandstone because its macroscopic elastic behavior is known to be highly unusual, and the microscopic mechanisms producing this behavior are not understood. We chose Yucca Mountain tuff, because the fluid transport properties of the geologic structure at Yucca Mountain, Nevada could be relevant to the performance of a high level nuclear waste repository at that site. Neutron scattering methods have a number of properties that are extremely useful for the study of earth materials. In contrast to X-rays, neutrons have very low absorption cross-sections for most elements so that entire bulk samples of considerable size can be 'illuminated' by the neutron beam. Similarly, samples that are optically opaque can be readily investigated by inelastic neutron scattering techniques. Neutrons are equally sensitive to light atoms as to heavy atoms, and can, for example, readily distinguish between Al and Si, neighboring atoms in the periodic table that are difficult to tell apart by X-ray diffraction. Finally, neutrons are particularly sensitive to hydrogen and thus can be used to study the motions, both vibrational and diffusive, of H-containing molecules in rocks, most notably of course, water. Our studies were primarily studies of guest molecules (in our case, water) in a host material (rock). We used three neutron scattering techniques: quasielastic neutron scattering (QNS), inelastic neutron scattering (INS), and neutron powder diffraction (NPD). We used QNS to measure the translational and rotational diffusional motion of water in rock; INS vibrational spectra allowed us to determine the nature of residual water in a sample (disassociated, chemisorbed, or physisorbed); and NPD measurements may allow us to determine the locations of residual water molecules (and the associated dynamic disorder), and thereby understand the binding of water molecules in our samples.
McCall, K. R.
Doing Neutron Scattering Science with the Multi-Axis Crystal ...
... at the NIST Center for Neutron Research began commissioning operation on ... and Internal Stress Analysis after High Temperature Corrosion in Power Plants.
A High Intensity Neutron Scattering Techniques for Hydrogen ...
Nucleation and Growth Observed by Ultrafast SAXS and WAXS � O10: Effect of Nickel on the Neutron Irradiation Sensitivity of Nuclear Reactor Pressure Vessel�...
Microsoft PowerPoint - Herwig-QuasielasticNeutronScattering.pptx
Ken Herwig Ken Herwig Deputy Director Neutron Facilities Development Division p Oak Ridge National Laboratory J 14 2011 June 14, 2011 OUTLINE * Background - the incoherent...
The Neutron Scattering Society www.neutronscattering.org
Abstract submitted to the XXXIst International Conference on High Energy Physics 24--31 July 2002, Amsterdam, The Netherlands Abstract: 000 Parallel Sessions: 0,0 Leading neutron production in e + p collisions at HERA ZEUS Collaboration Abstract The production of neutrons carrying at least 20% of the proton
Chen, Sow-Hsin
Educational Programs - National School on Neutron & X-ray Scattering
and national laboratories, will include basic tutorials on the principles of scattering theory and the characteristics of the sources, as well as seminars on the application of...
MCNP benchmarking of an inelastic neutron scattering system for...
carbon signal depends on the transport conditions of neutrons and gamma rays in the soil matrix, which are affected by the soil moisture and bulk density. While variations in the...
Neutron scattering workshop promotes high-pressure research ...
long-term goals in these areas closer to reality, Oak Ridge National Laboratory (ORNL), home of the Spallation Neutron Source (SNS) and the High Flux Isotope Reactor, is hosting...
Determination of hydrogen in niobium by cold neutron prompt gamma ray activation analysis and neutron incoherent scattering
The presence of trace amounts of hydrogen in niobium is believed to have a detrimental effect on the mechanical and superconducting properties. Unfortunately, few techniques are capable of measuring hydrogen at these levels. We have developed two techniques for measuring hydrogen in materials. Cold neutron prompt gamma-ray activation analysis (PGAA) has proven useful for the determination of hydrogen and other elements in a wide variety of materials. Neutron incoherent scattering (NIS), a complementary tool to PGAA, has been used to measure trace hydrogen in titanium. Both techniques were used to study the effects of vacuum heating and chemical polishing on the hydrogen content of superconducting niobium.
R.L. Paul; H.H. Cheu-Maya; G.R. Myneni
Neutron scattering characterization of pure and rare-earth modified zirconia catalysis.
The combined application of neutron powder diffraction, small angle neutron scattering and neutron inelastic scattering has led to improved understanding of the crystal phases, defect structure, microstructure and hydroxyl/water dynamics in pure and lanthanide-modified zirconia catalysts. Powder diffraction experiments quantified the degree of stabilization and provided evidence for static, oxygen vacancy-induced atomic displacements in stabilized zirconia. Quantitative assessment of Bragg peak breadths led to measurements of ''grain size'', representing coherency length of long-range ordered atomic arrangements (crystals). Small angle neutron scattering provided a separate measurement of ''grain size'', representing the average size of the primary particles in the aggregates, and the evolution of porosity (micro- versus meso-) and surface roughness caused by RE modification and heat treatment. Finally, the dynamics of hydrogen atoms associated with surface hydroxyls and adsorbed water was investigated by neutron-inelastic scattering, revealing changes in frequency and band breadth of O-H stretch, H-O-H bend, and librational motion of water molecules.
Loong, C.-K.; Ozawa, M.; Richardson, J. W., Jr.; Suzuki, S.; Thiyagarajan, P.
Coherent Scattering Investigations at the Spallation Neutron Source: a Snowmass White Paper
The Spallation Neutron Source (SNS) at Oak Ridge National Laboratory, Tennessee, provides an intense flux of neutrinos in the few tens-of-MeV range, with a sharply-pulsed timing structure that is beneficial for background rejection. In this white paper, we describe how the SNS source can be used for a measurement of coherent elastic neutrino-nucleus scattering (CENNS), and the physics reach of different phases of such an experimental program (CSI: Coherent Scattering Investigations at the SNS).
D. Akimov; A. Bernstein; P. Barbeau; P. Barton; A. Bolozdynya; B. Cabrera-Palmer; F. Cavanna; V. Cianciolo; J. Collar; R. J. Cooper; D. Dean; Y. Efremenko; A. Etenko; N. Fields; M. Foxe; E. Figueroa-Feliciano; N. Fomin; F. Gallmeier; I. Garishvili; M. Gerling; M. Green; G. Greene; A. Hatzikoutelis; R. Henning; R. Hix; D. Hogan; D. Hornback; I. Jovanovic; T. Hossbach; E. Iverson; S. R. Klein; A. Khromov; J. Link; W. Louis; W. Lu; C. Mauger; P. Marleau; D. Markoff; R. D. Martin; P. Mueller; J. Newby; J. Orrell; C. O'Shaughnessy; S. Pentilla; K. Patton; A. W. Poon; D. Radford; D. Reyna; H. Ray; K. Scholberg; V. Sosnovtsev; R. Tayloe; K. Vetter; C. Virtue; J. Wilkerson; J. Yoo; C. H. Yu
Is there an Ay problem in low-energy neutron-proton scattering?
We calculate Ay in neutron-proton scattering for the interactions models WJC-1 and WJC-2 in the Covariant Spectator Theory. We find that the recent 12 MeV measurements performed at TUNL are in better agreement with our results than with the Nijmegen Phase Shift Analysis of 1993, and after reviewing the low-energy data, conclude that there is no Ay problem in low-energy np scattering.
Gross, Franz
Franz Gross; Alfred Stadler
Use of a high repetition rate neutron generator for in vivo body composition measurements via neutron inelastic scattering
A small D-T neutron generator with a high pulse rate is used for the in vivo measurement of body carbon, oxygen and hydrogen. The core of the neutron generator is a 13 cm-long Zetatron tube pulsed at a rate of 10 kHz delivering 10/sup 3/ to 10/sup 4/ neutrons per pulse. A target-current feedback system regulates the source of the accelerator to assure constant neutron output. Carbon is measured by detecting the 4.44 MeV ..gamma..-rays from inelastic scattering. The short half-life of the 4.44 MeV state of carbon requires detection of the ..gamma..-rays during the 10 ..mu..s neutron pulse. Generators with low pulsing rate were found inappropriate for carbon measurements because of their low duty-cycle (high neutron output during the pulse). In vivo measurements were performed with normal volunteers using a scanning bed facility for a dose less than 25 mrem. This technique offers medical as well as general bulk analysis applications. 8 refs., 5 figs.
Kehayias, J.J.; Ellis, K.J.; Cohn, S.H.; Weinlein, J.H.
Neutron scattered dose equivalent to a fetus from proton radiotherapy of the mother
Scattered neutron dose equivalent to a representative point for a fetus is evaluated in an anthropomorphic phantom of the mother undergoing proton radiotherapy. The effect on scattered neutron dose equivalent to the fetus of changing the incident proton beam energy, aperture size, beam location, and air gap between the beam delivery snout and skin was studied for both a small field snout and a large field snout. Measurements of the fetus scattered neutron dose equivalent were made by placing a neutron bubble detector 10 cm below the umbilicus of an anthropomorphic Rando[reg] phantom enhanced by a wax bolus to simulate a second trimester pregnancy. The neutron dose equivalent in milliSieverts (mSv) per proton treatment Gray increased with incident proton energy and decreased with aperture size, distance of the fetus representative point from the field edge, and increasing air gap. Neutron dose equivalent to the fetus varied from 0.025 to 0.450 mSv per proton Gray for the small field snout and from 0.097 to 0.871 mSv per proton Gray for the large field snout. There is likely to be no excess risk to the fetus of severe mental retardation for a typical proton treatment of 80 Gray to the mother since the scattered neutron dose to the fetus of 69.7 mSv is well below the lower confidence limit for the threshold of 300 mGy observed for the occurrence of severe mental retardation in prenatally exposed Japanese atomic bomb survivors. However, based on the linear no threshold hypothesis, and this same typical treatment for the mother, the excess risk to the fetus of radiation induced cancer death in the first 10 years of life is 17.4 per 10 000 children.
Mesoloras, Geraldine; Sandison, George A.; Stewart, Robert D.; Farr, Jonathan B.; Hsi, Wen C. [School of Health Sciences, Purdue University, West Lafayette, Indiana 47906 (United States); Midwest Proton Radiotherapy Institute (MPRI), Bloomington, Indiana 47408 (United States)
HFIR Experiment Facilities | ORNL Neutron Sciences
Scattering Scattering Neutron Scattering Facilities at HFIR 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 building. The currently available instruments and the status of new instruments can be found on the HFIR Instrument Systems pages. Particularly prominent in the cold neutron guide hall are the two small-angle neutron scattering (SANS) instruments, each terminating in a 70-ft-long evacuated cylinder containing a large moveable neutron detector. In addition to the instruments, laboratories are equipped for users to prepare samples. Perhaps the most exciting development at HFIR is the successfully
phase behavior in carbon pores phase behavior in carbon pores Neutrons measure phase behavior in pores at angstrom size Compelling new methods for assessing carbon pores for hydrogen storage in fuel cells Research Contact: Yuri Melnichenko Jan. 2012, Written by Agatha Bardoel Yuri Melnichenko and Lilin He GP-SANS instrument scientist Yuri Melnichenko (left) and postdoctoral associate Lilin He. Researchers have measured the phase behavior of green house gases in pores at the angstrom level, using small-angle neutron scattering (SANS) at the Oak Ridge National Laboratory's High Flux Isotope Reactor. Yuri Melnichenko, an instrument scientist on the General-Purpose Small-Angle Neutron Scattering (GP-SANS) Diffractometer at ORNL's High Flux Isotope Reactor, his postdoctoral associate Lilin He and collaborators
The Los Alamos Neutron Scattering Center data acquisition system
The FASTBUS subsystem of the LANSCE data acquisition system consists of a single FASTBUS crate segment with four custom modules and a QPI interface for the VAX. Since experiments at the LANSCE facility always include a time-of-flight parameter for the detected neutron and may optionally include additional position parameters characterizing the event, a time stamp is generated for each event by the Programmable Master Clock (PMC) module. The time and any position information are latched into the Time-Of-Flight buffer (TOF) module. After all events associated with a single neutron burst have been captured in a frame buffer internal to the TOF module, each event is analyzed by the MAPPER module and reduced to a histogram address to increment in the BULKSTORE module. Software access to the histogram is provided through the QPI interface.
Nelson, R.O.; Cort, G.; Gjovig, A.; Goldstone, J.A.; McMillan, D.E.; Ross, J.; Seal, J.; Machen, D.R.
Collocation method for the solution of the neutron transport equation with both symmetric and asymmetric scattering
A collocation method is developed for the solution of the one-dimensional neutron transport equation in slab geometry with both symmetric and polarly asymmetric scattering. For the symmetric scattering case, it is found that the collocation method offers a combination of some of the best characteristics of the finite-element and discrete-ordinates methods. For the asymmetric scattering case, it is found that the computational cost of cross-section data processing under the collocation approach can be significantly less than that associated with the discrete-ordinates approach. A general diffusion equation treating both symmetric and asymmetric scattering is developed and used in a synthetic acceleration algorithm to accelerate the iterative convergence of collocation solutions. It is shown that a certain type of asymmetric scattering can radically alter the asymptotic behavior of the transport solution and is mathematically equivalent within the diffusion approximation to particle transport under the influence of an electric field. The method is easily extended to other geometries and higher dimensions. Applications exist in the areas of neutron transport with highly anisotropic scattering (such as that associated with hydrogenous media), charged-particle transport, and particle transport in controlled-fusion plasmas. 23 figures, 6 tables.
Morel, J.E.
The LANSCE (Los Alamos Neutron Scattering Center) target system
During the summer of 1985, we replaced the WNR T-shaped target/moderator scheme with the LANSCE split-target/flux-trap-moderator design. The intent of this 'LANSCE upgrade' was to increase (to 12) the number of neutron beam lines serviced simultaneously, and to enhance the target area shielding and target system to accept 200 ..mu..A of 800-MeV protons. The four LANSCE moderators consist of three (chilled) water moderators, and a liquid hydrogen (20 K) moderator. The LANSCE target is machinable tungsten.
Russell, G.J.; Robinson, H.; Legate, G.L.; Woods, R.; Whitaker, E.R.; Bridge, A.; Hughes, K.J.
Review of the Lujan neutron scattering center: basic energy sciences prereport February 2009
The Lujan Neutron Scattering Center (Lujan Center) at LANSCE is a designated National User Facility for neutron scattering and nuclear physics studies with pulsed beams of moderated neutrons (cold, thermal, and epithermal). As one of five experimental areas at the Los Alamos Neutron Science Center (LANSCE), the Lujan Center hosts engineers, scientists, and students from around the world. The Lujan Center consists of Experimental Room (ER) 1 (ERl) built by the Laboratory in 1977, ER2 built by the Office of Basic Energy Sciences (BES) in 1989, and the Office Building (622) also built by BES in 1989, along with a chem-bio lab, a shop, and other out-buildings. According to a 1996 Memorandum of Agreement (MOA) between the Defense Programs (DP) Office of the National Nuclear Security Agency (NNSA) and the Office of Science (SC, then the Office of Energy Research), the Lujan Center flight paths were transferred from DP to SC, including those in ERI. That MOA was updated in 2001. Under the MOA, NNSA-DP delivers neutron beam to the windows of the target crypt, outside of which BES becomes the 'landlord.' The leveraging nature of the Lujan Center on the LANSCE accelerator is a substantial annual leverage to the $11 M BES operating fund worth approximately $56 M operating cost of the linear accelerator (LINAC)-in beam delivery.
Scattering Print Scattering Print When a crystalline sample is illuminated with x-rays, the x-rays are scattered (diffracted) into very specific directions with various intensities. Detectors are used to measure this "diffraction pattern," which is then processed by computers to deduce the arrangement of atoms within the crystal. Hard x-rays have wavelengths comparable to the distance between atoms. Essentially everything we know about the atomic structure of materials is based on results from x-ray and neutron diffraction. From advanced ceramics to catalysts, from semiconductor technology to the frontiers of medicine, and from new magnetic materials and devices to framework compounds used to sequester radioactive waste, crystallography using hard x-ray diffraction techniques at synchrotron radiation facilities plays a crucial role in our ability to understand and control the world in which we live.
Kinetic energy of hydrogen in. beta. -V sub 2 H studied by neutron Compton scattering
Hydrogen dissolves in nearly all metals in large quantities, occupying interstitial sites which are energetic minima of the hydrogen potential. Experimentally, this potential can be determined by neutron vibrational spectroscopy (NVS) and, recently, by neutron Compton scattering (NCS) i.e. either by a measurement of the excitation energies of the localized hydrogen vibrations or by a measurement of the hydrogen momentum distribution. In this brief communication we report on what we believe is the first NCS experiment on a metal hydride. For the system to be investigated we chose {beta}-V{sub 2}H, an ordered hydride phase with hydrogen on pseudotetragonal octahedral sites. 3 figs., 7 refs.
Hempelmann, R.; Richter, D. (Forschungszentrum Juelich GmbH (Germany, F.R.). Inst. fuer Festkoerperforschung); Price, D.L. (Argonne National Lab., IL (USA))
Dynamic behavior of hydration water in calcium-silicate-hydrate gel: A quasielastic neutron scattering spectroscopy investigation
The translational dynamics of hydration water confined in calcium-silicate-hydrate (C-S-H) gel was studied by quasielastic neutron scattering spectroscopy in the temperature range from 280 to 230 K. The stretch exponent ...
Li, Hua
Measurement of the neutron magnetic form factor from inclusive quasielastic scattering of polarized electrons from polarized [sup 3]He
We report a measurement of the asymmetry in spin-dependent quasielastic scattering of longitudinally polarized electrons from a polarized [sup 3]He target. The neutron magnetic form factor [ital G][sup [ital n
Gao, H.; Arrington, J.; Beise, E.J.; Bray, B.; Carr, R.W.; Filippone, B.W.; Lung, A.; McKeown, R.D.; Mueller, B.; Pitt, M.L. (California Institute of Technology, Pasadena, California 91125 (United States)); Jones, C.E. (Argonne National Laboratory, Argonne, Illinois 60439 (United States)); DeSchepper, D.; Dodson, G.; Dow, K.; Ent, R.; Farkhondeh, M.; Hansen, J.; Korsch, W.; Kramer, L.H.; Lee, K.; Makins, N.; Milner, R.G.; Tieger, D.R.; Welch, T.P. (Bates Linear Accelerator Center, Laboratory for Nuclear Science and Department of Physics, Massachusetts Institute of Technology, Cambridge, Masschusetts 02139 (United States)); Candell, E.; Napolitano, J.; Wojtsekhowski, B.B.; Tripp, C. (Rensselaer Polytechnic Institute, Troy, New York 12180 (United States)); Lorenzon, W. (TRIUMF, Vancouver, British Columbia, V6T 2A3 (Canada))
Neutron scattering from elemental indium, the optical model, and the bound-state potential
Neutron differential elastic-scattering cross sections of elemental indium are measured from 4.5 to 10 MeV at incident-energy intervals of {approx}500 keV. Seventy or more differential values are obtained at each incident energy, distributed between {approx}18{degree} and 160{degree}. These experimental results are combined with lower-energy values previously obtained at this laboratory, and with 11 and 14 MeV results in the literature, to form a comprehensive elastic-scattering database extending from {approx}1.5 to 14 MeV. These data are interpreted in terms of a conventional spherical optical model. The resulting potential is extrapolated to the bound-state regime. It is shown that in the middle of the 50--82 neutron shell, the potential derived from the scattering results adequately describes the binding energies of article states, but does not do well for hole states. The latter shortcoming is attributed to the holes states having occupational probabilities sufficiently different from unity, so that the exclusion principle become a factor, and to the rearrangement of the neutron core. 68 refs.
Chiba, S. (Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan)); Guenther, P.T.; Lawson, R.D.; Smith, A.B. (Argonne National Lab., IL (USA))
Method for improving the angular resolution of a neutron scatter camera
DOE Patents (OSTI)
An instrument that will directly image the fast fission neutrons from a special nuclear material source wherein the neutron detection efficiency is increased has been described. Instead of the previous technique that uses a time-of-flight (TOF) between 2 widely spaced fixed planes of neutron detectors to measure scatter neutron kinetic energy, we now use the recoil proton energy deposited in the second of the 2 scatter planes which can now be repositioned either much closer together or further apart. However, by doubling the separation distance between the 2 planes from 20 cm to a distance of 40 cm we improved the angular resolution of the detector from about 12.degree. to about 10.degree.. A further doubling of the separation distance to 80 cm provided an addition improvement in angular resolution of the detector to about 6.degree. without adding additional detectors or ancillary electronics. The distance between planes also may be dynamically changed using a suitable common technique such as a gear- or motor-drive to toggle between the various positions. The angular resolution of this new configuration, therefore, is increased at the expanse of detection sensitivity. However, the diminished sensitivity may be acceptable for those applications where the detector is able to interrogate a particular site for an extended period.
Mascarenhas, Nicholas; Marleau, Peter; Gerling, Mark; Cooper, Robert Lee; Mrowka, Stanley; Brennan, James S.
ORNL Neutron Sciences
ORNL's Neutron Science Future: Integrating Neutron Scattering Across the Laboratory Greg Smith, HFIR Center for Neutron Scattering Upgrade Status and Scientific Opportunities...
Publications from Research Conducted at Bio-SANS | ORNL Neutron Sciences
Publications from Research Conducted at Bio-SANS Publications from Research Conducted at Bio-SANS 2013 Publications Brosey C. A., Yan C., Tsutakawa S. E., Heller W. T., Rambo R. P., Tainer J. A., Ivanov I., Chazin W. J., "A new structural framework for integrating replication protein A into DNA processing machinery", Nucleic Acids Research 41, 2313-2327 (2013). Crawford M.K., Smalley R.J., Cohen G., Hogan B., Wood B., Kumar S.K., Melnichenko Y.B., He L., Guise W., Hammouda and B., "Chain conformation in polymer nanocomposites with uniformly dispersed nanoparticles", Physical Review Letters 110, 196001 (2013). Dergunov S., Richter A. G., Kim M. D., Pingali S. V., Urban V., Pinkhassik E., "Synergistic self-assembly of scaffolds and building blocks for directed synthesis of organic nanomaterials", Chemical Communications
Nanostructure of a-Si:H and related alloys by small-angle scattering of neutrons and X-rays: Annual technical progress report: May 22, 1998 -- May 21, 1999
This report describes work being performed to provide details of the microstructure in high-quality hydrogenated amorphous silicon and related alloys on the nanometer scale. The materials under study are being prepared by state-of-the-art deposition methods, as well as by new and emerging deposition techniques. The purpose is to establish the role of nanostructural features in controlling opto-electronic and photovoltaic properties. The approach centers around the use of the uncommon technique of small-angle scattering of both X-rays (SAXS) and neutrons (SANS). SAXS has already been established as highly sensitive to microvoids and columnar-like microstructure. A major goal of this research is to establish the sensitivity of SANS to the hydrogen nanostructure. Conventional X-ray diffraction techniques are being used to examine medium-range order and microcrystallinity, particularly near the boundary between amorphous and microcrystalline material.
Williamson, D. L.
Education | ORNL Neutron Sciences
Education banner Education banner Sunil Sinha A Chat with Sunil Sinha, Distinguished Professor of Physics at the University of California-San Diego and speaker at the recent CNMS-SNS Research Forum more... The purpose of the Spallation Neutron Source and the High Flux Isotope Reactor is to facilitate neutron scattering as an integral tool for scientific research and technological development across many scientific and engineering domains within the scientific, academic,and industrial communities. Coupled with this role is a recognized need to inspire, educate, and facilitate the next generation of users and hence foster enhanced use of the unique neutron scattering facilities at ORNL. This is the central theme of the education activities within the Neutron Sciences Directorate (NScD).
ORNL neutron facilities deliver neutrons
The High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory (ORNL) resumed full power operations on May 16, 2007. There were three experiment cycles of 23 to 25 days in FY2007 and another six are proposed for FY2008 beginning in November 2007. During FY 2007, the High Flux Isotope Reactor delivered 1178 operating hours to users. Commissioning of two SANS instruments is under way and these instruments will join the user program in 2008. The Neutron Scattering Science Advisory Committee endorsed language encouraging development of the science case for two instruments proposed for HFIR.
Ekkebus, Allen E [ORNL
Quasielastic neutron scattering of -NH3 and -BH3 rotational dynamics in orthorhombic ammonia borane
Neutrons scattering techniques are ideally suited to directly probe H in materials due to the large incoherent scattering cross-section of hydrogen atom, and have been invaluable in providing direct insight into the local fluctuations and large amplitude motions in AB. Dihydrogen bonding may have a significant affect on materials to be used to store hydrogen for fuel-cell powered applications. We have noticed a trend of low temperature release of H2 in materials composed of hydridic and protonic hydrogen. This phenomenon has caught our attention and motivated our interest to gain more insight into dihydrogen bonding interactions in AB. We present results from a thorough Quasielastic Neutron Scattering (QENS) investigation of diffusive hydrogen motion in NH311BH3 and ND311BH3 to obtain (1) a direct measure of the rotational energy barriers the protonated species and (2) a confirmation of the 3-site jump model for rotational motion. The amplitude of the energy barrier of rotation of BH3 and NH3 determined by QENS are compared to those determined for BD3 and ND3 determined by 2H NMR studies.
Hess, Nancy J.; Hartman, Michael R.; Brown, Craig; Mamontov, Eugene; Karkamkar, Abhijeet J.; Heldebrant, David J.; Daemen, Luke L.; Autrey, Thomas
Exploration of deeply virtual Compton scattering on the neutron in the Hall A of Jefferson Laboratory
Generalized Parton Distributions (GPDs) are universal functions which provide a comprehensive description of hadron properties in terms of quarks and gluons. Deeply Virtual Compton Scattering (DVCS) is the simplest hard exclusive process involving GPDs. In particular, the DVCS on the neutron is mostly sensitive to E, the less constrained GPD, wich allows to access to the quark angular momentum. The first dedicated DVCS experiment on the neutron ran in the Hall A of Jefferson Lab in fall 2004. The high luminosity of the experiment and the resulting background rate recquired specific devices which are decribed in this document. The analysis methods and the experiment results, leading to preliminary constraints on the GPD E, are presented.
Malek Mazouz
Deeply virtual Compton scattering on longitudinally polarized protons and neutrons at CLAS
This paper focuses on a measurement of deeply virtual Compton scattering (DVCS) performed at Jefferson Lab using a nearly-6-GeV polarized electron beam, two longitudinally polarized (via DNP) solid targets of protons (NH{sub 3}) and deuterons (ND{sub 3}) and the CEBAF Large Acceptance Spectrometer. Here, preliminary results for target-spin asymmetries and double (beam-target) asymmetries for proton DVCS, as well as a very preliminary extraction of beam-spin asymmetry for neutron DVCS, are presented and linked to Generalized Parton Distributions.
Silvia Niccolai
Synthesis and characterization of nanophase zirconia : reverse micelle method and neutron scattering study.
Zirconia is an important transition-metal oxide for catalytic applications. It has been widely used in automotive exhaust treatment, methanol synthesis, isomerization, alkylation, etc. [1]. Nanophase materials have unique physiochemical properties such as quantum size effects, high surface area, uniform morphology, narrow size distribution, and improvement of sintering rates[2]. Microemulsion method provides the means for controlling the microenvironment under which specific chemical reactions may occur in favoring the formation of homogeneous, nanometer-size particles. In this paper, we report the synthesis of nanophase zirconia and the characterization of the microemulsions as well as the powders by small- and wide-angle neutron scattering techniques.
Li, X.
Use of Small Angle Neutron Scattering to Study Various Properties of Wool and Mohair Fibres
To maintain a competitive edge in the wool and mohair industry, a detailed knowledge and understanding of the properties of wool fibres is essential. Standard techniques are used to determine fibre diameter, length and strength; however, properties such as hydroscopicity, lustre and changes in fibre structure following chemical or mechanical treatment are not so well understood. The unique capabilities of small angle neutron scattering to study changes in the supermolecular structure of wool fibres, particularly at the level of the microfibril-matrix complex, have been used to provide previously unknown features of the fibres. The results of these studies are presented.
Franklyn, C. B. [Radiation Science Department, Necsa, PO Box 582, Pretoria 0001 (South Africa); Toeroek, Gy. [Research Institute for Solid State Physics and Optics, H-1525 Budapest, POB 49 (Hungary)
Data Processing for the SNS EQ-SANS Diffractometer
The scattering data on the Extended Q-Range Small Angle Scattering Diffractometer at the Spallation Neutron Source are stored as neutron events. Each event has two parts: the time of fight of the detected neutron, and an identifier for the neutron's location on the detector. In addition, each event is associated with the source pulse from which the neutron is originated. Due to the high neutron beam intensity at the SNS, the size of the stored data files can easily exceed several Gigabytes. Processing and reducing these data can be very time consuming. The standard way of handling the data at the SNS has been to first transform the data into histograms. On the EQ-SANS, these histograms are further processed into intensity I vs. neutron momentum transfer Q files, I(Q). For a large data, the whole process can take many minutes to hours to complete, which severely limits the turnaround time of an experiment. Experimenters often want to reduce the data quickly and depending on the result, make decisions on the setup of next measurements. They may also need to reduce the data using different inputs and conditions. In this work, we present the implementation of a fast data processing scheme for the EQ-SANS diffractometer. The scattering data are processed directly from neutron event files into I(Q) or other desired formats, greatly reducing the needed computation time. Further speed gains are obtained by the implementation of parallel computing under the Message Passing Interface framework. Most data on the EQ-SANS can now be handled in mere seconds. The process is highly automated. All relevant experimental information that is stored in instrument configuration files are read and processed. In addition, the new implementation is highly flexible. All the data corrections and handlings can be controlled transparently through user inputs. Finally, software implementation enables the slicing of neutron event, which can be used for the study of time dependent phenomena.
Zhao, Jinkui [ORNL
New thermal neutron scattering files for ENDF/B-VI release 2
At thermal neutron energies, the binding of the scattering nucleus in a solid, liquid, or gas affects the cross section and the distribution of secondary neutrons. These effects are described in the thermal sub-library of Version VI of the Evaluated Nuclear Data Files (ENDF/B-VI) using the File 7 format. In the original release of the ENDF/B-VI library, the data in File 7 were obtained by converting the thermal scattering evaluations of ENDF/B-III to the ENDF-6 format. These original evaluations were prepared at General Atomics (GA) in the late sixties, and they suffer from accuracy limitations imposed by the computers of the day. This report describes new evaluations for six of the thermal moderator materials and six new cold moderator materials. The calculations were made with the LEAPR module of NJOY, which uses methods based on the British code LEAP, together with the original GA physics models, to obtain new ENDF files that are accurate over a wider range of energy and momentum transfer than the existing files. The new materials are H in H{sub 2}O, Be metal, Be in BeO, C in graphite, H in ZrH, Zr in ZrH, liquid ortho-hydrogen, liquid para-hydrogen, liquid ortho-deuterium, liquid para-deuterium liquid methane, and solid methane.
MacFarlane, R.E.
The use of chopper spectrometers for cold-to-epithermal neutron scattering at IPNS
A multi-detector chopper spectrometer enables measurements of the scattering function S(Q,E) to be made over a wide range of momentum and energy transfer (Q,E). The application of pulsed-source chopper spectrometers for inelastic measurements at thermal and epithermal energies (50 meV < E < 1000 meV) is well known. Recently at IPNS, we have extended the energy-transfer region down to about 0.5 meV with a resolution of the order of 150 {mu}eV. It is made possible by utilizing the cold-neutron incident spectrum of the 100 K methane moderator in conjunction with a dual beryllium-body rotor system. Neutron incident energies can be changed efficiently over the 4 to 1000 meV region while maintaining an undisturbed sample environment. We describe the operation of the IPNS chopper spectrometers (HRMECS and LRMECS), the instrumental resolution and the background-suppression performance. The capability of measuring inelastic features from 0.5 to 100 meV with an energy resolution of {Delta}E/E{sub 0} = 2.5% is demonstrated by experimental results of crystal-field excitation spectra of a high-Tc superconductor ErBa{sub 2}Cu{sub 3}O{sub 7}. Preliminary data of quasielastic scattering from a room-temperature molten salt AlCl{sub 3}-EMIC are presented.
Loong, C.K.; Donley, L.I.; Ostrowski, G.E.; Kleb, R.; Hammonds, J.P.; Soderholm, L.; Takahashi, S.
The Manuel Lujan Jr. Neutron Scattering Center (LANSCE) experiment reports 1993 run cycle. Progress report
This year the Manuel Lujan Jr. Neutron Scattering Center (LANSCE) ran an informal user program because the US Department of Energy planned to close LANSCE in FY1994. As a result, an advisory committee recommended that LANSCE scientists and their collaborators complete work in progress. At LANSCE, neutrons are produced by spallation when a pulsed, 800-MeV proton beam impinges on a tungsten target. The proton pulses are provided by the Clinton P. Anderson Meson Physics Facility (LAMPF) accelerator and a associated Proton Storage Ring (PSR), which can Iter the intensity, time structure, and repetition rate of the pulses. The LAMPF protons of Line D are shared between the LANSCE target and the Weapons Neutron Research (WNR) facility, which results in LANSCE spectrometers being available to external users for unclassified research about 80% of each annual LAMPF run cycle. Measurements of interest to the Los Alamos National Laboratory (LANL) may also be performed and may occupy up to an additional 20% of the available beam time. These experiments are reviewed by an internal program advisory committee. This year, a total of 127 proposals were submitted. The proposed experiments involved 229 scientists, 57 of whom visited LANSCE to participate in measurements. In addition, 3 (nuclear physics) participating research teams, comprising 44 scientists, carried out experiments at LANSCE. Instrument beam time was again oversubscribed, with 552 total days requested an 473 available for allocation.
Farrer, R.; Longshore, A. [comps.
Development and Validation of Temperature Dependent Thermal Neutron Scattering Laws for Applications and Safety Implications in Generation IV Reactor Designs
The overall obljectives of this project are to critically review the currently used thermal neutron scattering laws for various moderators as a function of temperature, select as well documented and representative set of experimental data sensitive to the neutron spectra to generate a data base of benchmarks, update models and models parameters by introducing new developments in thermalization theory and condensed matter physics into various computational approaches in establishing the scattering laws, benchmark the results against the experimentatl set. In the case of graphite, a validation experiment is performed by observing nutron slowing down as a function of temperatures equal to or greater than room temperature.
Ayman Hawari
Dr. George Wignall | ORNL Neutron Sciences
Dr. George D. Wignall Dr. George D. Wignall Consultant: General-Purpose SANS Instrument (CG-2), HFIR Education Ph.D. in Physics, Sheffield University, England Description of Research Dr. Wignall uses small-angle neutron scattering (SANS) to study the structure of homo-polymers, block-copolymers and polymer blends, using deuterium labeling techniques to "color" polymer molecules and make them "visible" in the condensed state. He makes SANS techniques and instrumentation available to the scientific community through the operation of user-friendly facilities. Selected Publications (from over 240) Y. B. Melnichenko and G. D. Wignall, "Small Angle Neutron Scattering in Materials Science: Recent Practical Applications," Journal of Applied Physics 102 021102 (2007)
FUNDAMENTAL STUDIES OF CO2-COAL INTERACTIONS USING NEUTRON SCATTERING AT CONDITIONS RELEVANT sites CARBON CAPTURE AND STORAGE IN UNMINABLE COAL SEAMS IS IMPORTANT COMPONENT OF A PORTFOLIO OF CO2 AND SORPTION CAPACITY FOR CO2 IN DIFFERENT COAL SEAMS NEEDS: ACHIEVE FUNDAMENTAL UNDERSTANDING OF FLUID
Neutron Scattering Study of Quantum Phase Transitions inIntegral Spin Chains.
Quite a few low-dimensional magnets are quantum-disordered 'spin liquids' with a characteristic gap in the magnetic excitation spectrum. Among these are antiferromagnetic chains of integer quantum spins. Their generic feature are long-lived massive (gapped) excitations (magnons) that are subject to Zeeman splitting in external magnetic fields. The gap in one of the magnon branches decreases with field, driving a soft-mode quantum phase transition. The system then enters a qualitatively new high-field phase. The actual properties at high fields, particularly the spin dynamics, critically depend on the system under consideration. Recent neutron scattering studies of organometallic polymer crystals NDMAP (Haldane spin chains with anisotropy) and NTENP (dimerized S = 1 chains) revealed rich and unique physics.
Zheludev, Andrey I [ORNL
Small angle neutron scattering analysis of novel carbons for lithium secondary batteries.
Small angle neutron scattering analyses of carbonaceous materials used as anodes in lithium ion cells have been performed. The carbons have been synthesized using pillared clays (PILCs) as inorganic templates. Pillared clays are layered silicates whose sheets have been permanently propped open by sets of thermally stable molecular props. The calcined PILC was loaded with five different organic precursors and heated at 700 C under nitrogen. When the inorganic pillars were removed by acid treatment, carbon sheets are produced with holes. The fitting of the data in the high q region suggested that the carbon sheets have voids with radii ranging from 4 to 8 {angstrom}. Similar radii were obtained for the PILC and PILC/organic precursor, which suggests that the carbon was well distributed in the clay prior to pyrolysis.
Sandi, G.; Thiyagarajan, P.; Winans, R.; Carrado, K.
In situ determination of soil carbon pool by inelastic neutron scattering: Comparison with dry combustion
There is a well-documented need for new in situ technologies for elemental analysis of soil, particularly for carbon (C), that overcome the limitations of the currently established chemical method by dry combustion (DC). In this work, we evaluated the concordance between the new INS (inelastic neutron scattering) technology and the DC method. The comparisons were carried out in the high C content (30-40%) organic soils of Willard, Ohio (4 sites), in natural forest in Willard, Ohio (1 site), and in a watershed pasture, with an {approx} 10{sup o} slope, in Coshocton, Ohio (5 sites). In addition to these stationary measurements, the organic soil and the pasture were continuously scanned with the inelastic neutron scattering (INS) system to obtain the transects mean C value. Both types of measurements, INS and DC, registered a decline in the surface density of C along transects in the watershed and in the organic soil. Similarly, both recorded a drop in C in the organic soil of about 0.16%. In the pastureland, declines in C levels of 0.08% and 0.10% were observed, respectively, by DC and INS. Combining the results from the three sites yielded a very satisfactory correlation between the INS- and DC-responses, with a regression coefficient, r{sup 2}, value of about 0.99. This suggests the possibility of establishing a universal regression line for various soil types. In addition, we demonstrated the ability of INS to measure the mean value over transect. In organic soil the mean value of an INS scan agreed, {approx} 0.5%, with the mean values of the DC analysis, whereas large discrepancy between these two was recorded in the pastureland. Overall, the various trends observed in C measurements by INS concurred with those determined by the DC method, so enhancing the confidence in the new INS technology.
Wielopolski, L.; Mitra, S.; Chatterjee, A.; Lal, R.
Neutron Physics Group
... spectrum and fluencies is essential for several ... Neutron Interferometer and Optics Facility performed a ... other neutron scattering facilities depends on ...
ORNL Neutron Sciences Instruments
Instruments banner Instruments banner ORNL Neutron Sciences Instruments SNS and HFIR provide researchers with two complementary world-class suites of neutron scattering instruments and beam lines. All the instruments are supported by a variety of sample environments and data analysis and visualization capabilities. Before submitting a proposal for a specific instrument, please contact the appropriate instrument scientist to make sure your research is feasible for that instrument. Instruments Currently Available to Users SNS Beam Line Instrument Name HFIR Beam Line Instrument Name 1B NOMAD Nanoscale-Ordered Materials Diffractometer CG-1 Development Beam Line 2 BASIS Backscattering Spectrometer CG-1D IMAGING Neutron Imaging Prototype Facility 3 SNAP Spallation Neutrons and Pressure Diffractometer CG-2 GP-SANS
Characterization of nanostructured zirconia prepared by hydrolysis and reverse micelle synthesis by small-angle neutron and X-ray scattering
Low temperature techniques such as hydrolysis and reverse micelle syntheses provide the opportunity to determine the relationship between the structural properties and preparation conditions of zirconia powders as well as to tailor their physicochemical properties. The authors have performed small-angle neutron and synchrotron X-ray scattering (SANS and SAXS) experiments to study the nucleation and organization of zirconia nanoparticles via different preparation routes. First, the formation of reverse micelles in individual and mixed solutions of (ZrOCl{sub 2}+D{sub 2}O)/AOT/C{sub 6}D{sub 5}CD{sub 3}, and (NH{sub 4}OH+H{sub 2}O)/AOT/C{sub 6}D{sub 5}CD{sub 3} systems at water/AOT molar ratio of 20 was characterized. Second, the aggregation of zirconia gels obtained from the reaction of the reverse micelle solutions after heat treatments was studied. Third, the nanostructure of zirconia powders prepared by the reverse micelle method is compared with the corresponding powders prepared by hydrolysis after different heat treatments.
Thiyagarajan, P.; Li, X.; Littrell, K.; Seifert, S.; Csencsits, R.; Loong, C.
Neutron total and scattering cross sections of /sup 6/Li in the few MeV region
Neutron total cross sections of /sup 6/Li are measured from approx. 0.5 to approx. 4.8 MeV at intervals of approx. 10 scattering angles and at incident-neutron intervals of approx.< 100 keV. Neutron differential inelastic-scattering cross sections are measured in the incident-energy range 3.5 to 4.0 MeV. The experimental results are extended to lower energies using measured neutron total cross sections recently reported elsewhere by the authors. The composite experimental data (total cross sections from 0.1 to 4.8 MeV and scattering cross sections from 0.22 to 4.0 MeV) are interpreted in terms of a simple two-level R-matrix model which describes the observed cross sections and implies the reaction cross section in unobserved channels; notably the (n;..cap alpha..)t reaction (Q = 4.783 MeV). The experimental and calculational results are compared with previously reported results as summarized in the ENDF/B-V evaluated nuclear data file.
Smith, A.; Guenther, P.; Whalen, J.
Neutron and x-ray scattering studies of the metallurgical condition and residual stresses in Weldalite welds
Weldalite is a lithium-containing aluminum alloy which is being considered for aerospace applications because its favorable strength-to-weight ratio. Successful welding of this alloy depends on the control of the metallurgical condition and residual stresses in the heat affected zone. Neutron and x-ray scattering methods of residual stress measurement were applied to plasma arc welds made in aluminum-lithium alloy test panels as part of an evaluation of materials for use in welded structures. In the course of these studies discrepancies between x-ray and neutron results from the heat affected zone (HAZ) of the weld were found. Texture changes and recovery from the cold work, indicated in peak widths, were found in the HAZ as well. The consideration of x-ray and neutron results leads to the conclusion that there is a change in solute composition which modifies the d-spacings in the HAZ which affects the neutron diffraction determination of residual stresses. The composition changes give the appearance of significant compressive strains in the HAZ. This effect and sharp gradients in the texture give severe anomalies in the neutron measurement of residual stress. The use of combined x-ray and neutron techniques and the solution to the minimizing of the neutron diffraction anomalies are discussed.
Spooner, S. [Oak Ridge National Lab., TN (United States); Pardue, E.B.S. [Technology for Energy Corp., Knoxville, TN (United States)
Dr. J. K. (Jinkui) Zhao - ORNL Neutron Sciences
Dr. J.K. (Jinkui) Zhao Dr. J.K. (Jinkui) Zhao Research Staff Dr. Zhao is a research staff in the Neutron Facility Development Division at the Spallation Neutron Source. He has broad interests in many areas ranging from biophysics to neutrons scattering techniques. He was the lead scientist for Extended Q-Range Small-Angle Neutron Scattering Diffractometer (EQ-SANS) instrument during its design, construction and commissioning phases. Resources Software by J.K. Zhao EQ-SANS design documentation Selected Publications Metabolic Scaling in Biology Zhao, Jinkui. "A common origin for 3/4- and 2/3-power rules in metabolic scaling" Submitted Zhao, Jinkui. "Plants' metabolism and metabolic scaling" Submitted Zhao, Jinkui. "Tree growth model" In preparation Biomolecular Structures
A Search for non-Newtonian force in a precision measurement of the scattering of slow neutrons in Xenon gas
An experimental search for non-newtonian, gravity-like force in a precision measurement of the scattering of slow neutrons in Xenon gas is proposed. A preliminary experiment with small statistics of 25 hours irradiation time was performed and the observed scattering distribution is consistent with the expectation with no additional forces. A 95% CL limit on the coupling strength for a hypothetical force of 1 nm interaction range was evaluated to be 2*10^-15. The expected sensitivity for a planned high statistics runs is discussed.
Yoshio Kamiya; Misato Tani; Sachio Komamiya; Guinyun Kim; Kyungsuk Kim
''Inelastic Neutron Scattering and Periodic Density Functional Studies of Hydrogen Bonded Structures''
This project is directed at a fundamental understanding of hydrogen bonding, the primary reversible interaction leading to defined geometries, networks and supramolecular aggregates formed by organic molecules. Hydrogen bonding is still not sufficiently well understood that the geometry of such supramolecular aggregates can be predicted. In the approach taken existing quantum chemical methods capable of treating periodic solids have been applied to hydrogen bonded systems of known structure. The equilibrium geometry for the given space group and packing arrangement were computed and compared to that observed. The second derivatives and normal modes of vibration will then be computed and from this inelastic neutron scattering (INS) spectra were computed using the normal mode eigenvectors to compute spectral intensities. Appropriate inclusion of spectrometer line width and shape was made in the simulation and overtones, combinations and phonon wings were be included. These computed spectra were then compared with experimental results obtained for low-temperature polycrystalline samples at INS spectrometers at several facilities. This procedure validates the computational methodology for describing these systems including both static and dynamic aspects of the material. The resulting description can be used to evaluate the relative free energies of two or more proposed structures and so ultimately to be able to predict which structure will be most stable for a given building block.
Bruce S. Hudson
Soluble Hydrogen-bonding Interpolymer Complexes in Water: A Small-Angle Neutron Scattering Study
The hydrogen-bonding interpolymer complexation between poly(acrylic acid) (PAA) and the poly(N,N-dimethylacrylamide) (PDMAM) side chains of the negatively charged graft copolymer poly(acrylic acid-co-2-acrylamido-2-methyl-1-propane sulfonic acid)-graft-poly(N, N dimethylacrylamide) (P(AA-co-AMPSA)-g-PDMAM), containing 48 wt % of PDMAM, and shortly designated as G48, has been studied by small-angle neutron scattering in aqueous solution. Complexation occurs at low pH (pH hydrogen-bonding interpolymer complexes, whose radius is estimated to be around 165 A. As these particles involve more than five graft copolymer chains, they act as stickers between the anionic chains of the graft copolymer backbone. This can explain the characteristic thickening observed in past rheological measurements with these mixtures in the semidilute solution, with decreasing pH. We have also examined the influence of pH and PAA molecular weight on the formation of these nanoparticles.
Maria Sotiropoulou; Julian Oberdisse; Georgios Staikos
Status report on the analysis of inelastic neutron scattering from carbon, iron, yttrium and lead at 96 MeV
This work is part of an effort to provide more experimental data for the (n,n'x) reaction. The experiments were carried out at The Svedberg Laboratory in Uppsala, Sweden, at the quasi-mono-energetic neutron beam of 96 MeV, before the facility was upgraded in 2004. Using an extended data analysis of data primarily intended for measuring elastic neutron scattering only, it was found to be possible to extract information on the inelastic scattering from several nuclei. In the preliminary data analysis, an iterative forward-folding technique was applied, in which a physically reasonable trial spectrum was folded with the response function of the detector system and the output was compared to the experimental data. As a result, double-differential cross sections and angular distributions of inelastic neutron scattering from 12-C, 56-Fe, 89-Y and 208-Pb could be obtained. In this paper, a status update on the efforts to improve the description of the detector response function is given.
C. Gustavsson; C. Hellesen; S. Pomp; A. �hrn; J. Blomgren; U. Tippawan
Most of current computer-generated imagery represents scenes with clear atmospheres, neglecting light scattering effects, and most computer-vision systems have not enjoyed success when deployed in uncontrolled outdoor environments. Nevertheless, scattering ...
Diego Gutierrez; Wojciech Jarosz; Craig Donner; Srinivasa G. Narasimhan
Most computer-generated imagery represents scenes with clear atmospheres, neglecting light scattering effects. But scattering is a fundamental aspect of light transport in a wide range of applications, whether one is simulating it or interpreting it, ...
Diego Gutierrez; Henrik Wann Jensen; Wojciech Jarosz; Craig Donner
Characterization of the Neutron Fields in the Lawrence Livermore National Laboratory (LLNL) Radiation Calibration Laboratory Low Scatter Calibration Facility
In June 2007, the Department of Energy (DOE) revised its rule on Occupational Radiation Protection, Part 10 CFR 835. A significant aspect of the revision was the adoption of the recommendations outlined in International Commission on Radiological Protection (ICRP) Report 60 (ICRP-60), including new radiation weighting factors for neutrons, updated internal dosimetric models, and dose terms consistent with the newer ICRP recommendations. ICRP-60 uses the quantities defined by the International Commission on Radiation Units and Measurements (ICRU) for personnel and area monitoring including the ambient dose equivalent H*(d). A Joint Task Group of ICRU and ICRP has developed various fluence-to-dose conversion coefficients which are published in ICRP-74 for both protection and operational quantities. In February 2008, Lawrence Livermore National Laboratory (LLNL) replaced its old pneumatic transport neutron irradiation system in the Radiation Calibration Laboratory (RCL) Low Scatter Calibration Facility (B255, Room 183A) with a Hopewell Designs irradiator model N40. The exposure tube for the Hopewell system is located close to, but not in exactly the same position as the exposure tube for the pneumatic system. Additionally, the sources for the Hopewell system are stored in Room 183A where, prior to the change, they were stored in a separate room (Room 183C). The new source configuration and revision of the 10 CFR 835 radiation weighting factors necessitate a re-evaluation of the neutron dose rates in B255 Room 183A. This report deals only with the changes in the operational quantities ambient dose equivalent and ambient dose rate equivalent for neutrons as a result of the implementation of the revised 10 CFR 835. In the report, the terms 'neutron dose' and 'neutron dose rate' will be used for convenience for ambient neutron dose equivalent and ambient neutron dose rate equivalent unless otherwise stated.
Radev, R
Diffuse Scattering
Diffuse Scattering Diffuse Scattering * Anticipatory (trick) question: If you have an x-ray or neutron detector looking at a small sample volume, which will scatter more x- rays or neutrons into the detector 1 atom 100 atoms or 1000 atoms? X-ray or neutron beam Answer: Depends! Diffuse Scattering Gene E. Ice Materials Science and Technology Division Oak Ridge National Laboratory, USA National School on Neutron and X-ray Scattering ORNL/SNS June 2011 Presentation concentrates year graduate-level course into 1 hour * Skip mathematical complexities * Expose to range of applications * Develop intuition for length scales * Talk like x-ray/neutron scattering guru - Reciprocal space - Debye Temperature - Laue monotonic - Krivoglaz defects of 1st/2nd kinds! Great for cocktail parties or impressing attractive strangers-
National School on Neutron and X-Ray Scattering Held at APS&IPNS
Science and Chemistry Divisions but also from several Collaborative Access Teams (CATS) and the Spallation Neutron Source generously provided their time and expertise. We are...
A Survey of Students from the National School on Neutron and X-ray Scattering: Communication Habits and Preferences
Oak Ridge National Laboratory (ORNL) offers the scientific community unique access to two types of world-class neutron sources at a single site - the Spallation Neutron Source (SNS) and the High Flux Isotope Reactor (HFIR). The 85-MW HFIR provides one of the highest steady-state neutron fluxes of any research reactor in the world. And the SNS is one of the world's most intense pulse neutron beams. Management of these resources is the responsibility of the Neutron Sciences Directorate (NScD). NScD started conducting the National School on Neutron and X-ray Scattering (NXS) in conjunction with the Advanced Photon Source (APS) at Argonne National Laboratory in 2007. This survey was conducted to determine the most effective ways to reach students with information about what SNS and HFIR offer the scientific community, including content and communication vehicles. The emphasis is on gaining insights into compelling messages and the most effective channels, e.g., Web sites and social media, for communicating with students about neutron science The survey was conducted in two phases using a classic qualitative investigation to confirm language and content followed by a survey designed to quantify issues, assumptions, and working hypotheses. Phase I consisted of a focus group in late June 2010 with students attending NXS. The primary intent of the group was to inform development of an online survey. Phase two consisted of an online survey that was developed and pre-tested in July 2010 and launched on August 9, 2010 and remained in the field until September 9, 2010. The survey achieved an overall response rate of 48% for a total of 157 completions. The objective of this study is to determine the most effective ways to reach students with information about what SNS and HFIR offer the scientific community, including content and communication vehicles. The emphasis is on gaining insights into compelling messages and the most effective channels, e.g., Web sites, social media, for communicating with students about neutron science.
Bryant, Rebecca [Bryant Research, LLC
Scattering Length Density Calculator
... For energy dependent cross sections please go to ... The neutron scattering length density is defined ... To calculate scattering length densities enter a ...
Exploring local atomic arrangements in amorphous and metastable phase change materials with x-ray and neutron total scattering
Very little experimental work has conclusively explored the structural transformation between the amorphous and metastable crystalline phases of phase change chalcogenides. A recent flurry of theoretical work has supported likely mechanisms for the phase transition process in Ge-Sb-Te (GST) compositions and invigorated efforts at probing local atomic arrangements experimentally. The pair distribution function (PDF) formalism of total scattering data provides directly both local structure correlations at low real-space dimensions, and intermediate range order at higher length scales, a distinct advantage for following the relevant phase transition in phase change materials (PCM). A challenge facing the field is the difficulty in distinguishing separate peak contributions to pair correlation functions in amorphous and highly disordered samples. For example, various types of local order have been reported for Ge{sub x}Te{sub 1-x} phases, including both random mixtures and discrete structural units, and both 4-fold and 6-fold coordination around Ge. We describe our efforts in advancing capabilities for extracting and refining differential or partial pair distribution function data sets by combining neutron and x-ray total scattering, with extensions to isotopic substitution and anomalous x-ray scattering. Our results combining neutron and x-ray scattering for the Ge{sub x}Te{sub 1-x} series, for example, clearly distinguish Ge-Te and Te-Te contributions in nearest neighbor correlations. Presenting an additional challenge, phase change materials with fast switching speeds (those arguably of greatest technological interest) have stable bulk crystalline phases and do not readily form glasses until reduced to small dimensions. Thin film samples are inherently difficult to probe with conventional crystallographic methods. We demonstrate successful synchrotron x-ray total scattering experiments for PCM thin films with thicknesses between 100 nm and 1 um and describe how chemical short-range order and local bonding environments vary in amorphous, metastable and crystalline GeSb{sub 2}Te{sub 4} films. Total scattering methods for powders and thin films allow for a direct comparison of PCM properties (crystallization temperature, optical contrast between phases, phase change speed, etc.) with observed local structure and motivate further exploration into the atomic configurations enabling this fascinating class of materials.
Page, Katharine [Los Alamos National Laboratory; Daemen, Luc [Los Alamos National Laboratory; Proffen, Thomas [Los Alamos National Laboratory
NIST CNR SANS NG3 30 Meter SANS Instrument
... 3, Characterization of Fly Ash Reactivity in Hydrating Cement by Neutron Scattering, W. Bumrongjaroen, RA Livingston, DA Neumann, AJ Allen, J ...
Structural and magnetic properties of transition metal substituted BaFe{sub 2}As{sub 2} compounds studied by x-ray and neutron scattering
The purpose of my dissertation is to understand the structural and magnetic properties of the newly discovered FeAs-based superconductors and the interconnection between superconductivity, antiferromagnetism, and structure. X-ray and neutron scattering techniques are powerful tools to directly observe the structure and magnetism in this system. I used both xray and neutron scattering techniques on di#11;erent transition substituted BaFe2As2 compounds in order to investigate the substitution dependence of structural and magnetic transitions and try to understand the connections between them.
Kim, Min Gyu [Ames Laboratory
Time-of-Flight Bragg Scattering from Aligned Stacks of Lipid Bilayers using the Liquids Reflectometer at the Spallation Neutron Source
Time-of-flight (TOF) neutron diffraction experiments on aligned stacks of lipid bilayers using the horizontal Liquids Reflectometer at the Spallation Neutron Source are reported. Specific details are given regarding the instrumental setup, data collection and reduction, phase determination of the structure factors, and reconstruction of the one-dimensional neutron scattering length density (NSLD) profile. The validity of using TOF measurements to determine the one-dimensional NSLD profile is demonstrated by reproducing the results of two well known lipid bilayer structures. The method is then applied to show how an antimicrobial peptide affects membranes with and without cholesterol.
Pan, Jianjun [ORNL; Heberle, Frederick A [ORNL; Carmichael, Justin R [ORNL; Ankner, John Francis [ORNL; Katsaras, John [ORNL
Structure of light neutron-rich nuclei and mechanism of elastic proton scattering
Differential cross sections for elastic p{sup 6}He, p{sup 8}Li, and p{sup 9}Li scattering at two energies of 70 and 700 MeV per nucleon were calculated within the Glauber theory of multiple diffractive scattering. Threeparticle wave functions ({alpha}-n-n for {sup 6}He, {alpha}-t-n for {sup 8}Li, and {sup 7}Li-n-n for {sup 9}Li) were used for realistic potentials of intercluster interactions. The sensitivity of elastic scattering to proton-nucleus interaction and to the structure of nuclei was explored. In particular, the dependence of the differential cross section on the contribution of higher order collisions, on scattering on the core and peripheral nucleons, and on the contribution of small wave-function components and their asymptotic behavior was determined. A comparison with available experimental data and with the results of calculations within different formalisms was performed.
Ibraeva, E. T., E-mail: firstname.lastname@example.com [National Nuclear Center of the Republic of Kazakhstan, Institute of Nuclear Physics (Kazakhstan); Zhusupov, M. A. [Al-Farabi Kazakh National University (Kazakhstan); Imambekov, O. [National Nuclear Center of the Republic of Kazakhstan, Institute of Nuclear Physics (Kazakhstan)
Polyelectrolyte biomaterials - Research Highlights | ORNL Neutron Sciences
Home › Research › Highlights › Polyelectrolyte biomaterials Home › Research › Highlights › Polyelectrolyte biomaterials Detecting the shape of polymer chains inside polyelectrolyte biomaterials Bio-SANS research for replacing cartilage in the spine and knees Research Contact: Marie Markarian Feb. 2012, Written by Agatha Bardoel Left: neutron scattering with contrast variation reveals the coil conformation of single polymer molecules in a blend of PSS and PDADMA. Contrast variation is achieved by deuteration of some of the PSS molecules (D-PSS) in the mixture. Right: The slope of the scattering curve exhibits a power law dependence Q-2, which is a characteristic signature of the random coil conformation of a polymer chain molecule. Left: neutron scattering with contrast variation reveals the coil conformation of single polymer molecules in a blend of PSS and PDADMA.
Neutrons in Biology, ORNL
Scattering Sciences Division Oak Ridge National Laboratory Phone: 865.241.2897 SNS Logo HFIR Logo General Information The unique potential of neutron scattering in structural...
Scattering Sciences Division Oak Ridge National Laboratory Phone: 865.576.2779 SNS Logo HFIR Logo General Information The unique potential of neutron scattering in structural...
Journal of the Korean Physical Society, Vol. 55, No. 4, October 2009, pp. 13891393 Measurements of the Neutron Scattering Spectrum from 238
scattering, Resonance, Time-of-flight, Depleted uranium, LINAC experiment DOI: 10.3938/jkps.55.1389 I and p = 1.2. Two different thickness depleted uranium, with 0.3% U-235, samples were used the neutron time-of-flight (TOF) method and a 6 Li scintillation detector. Two different thickness depleted
Structure of neutron-rich Isotopes {sup 8}Li and {sup 9}Li and allowance for it in elastic scattering
The differential cross sections for elastic proton scattering on the unstable neutron-rich nuclei {sup 8}Li and {sup 9}Li at E = 700 and 60 MeV per nucleon were considered. The {sup 8}Li nucleus was treated on the basis of the three-body {alpha}-t-n model, while the {sup 9}Li nucleus was considered within the {alpha}-t-n and {sup 7}Li-n-n models. The cross sections in question were calculated within Glauber diffraction theory. A comparison of the results with available experimental data made it possible to draw conclusions on the quality of the wave functions and potential used in the calculations.
Ibraeva, E. T., E-mail: email@example.com [National Nuclear Center of the Republic of Kazakhstan, Institute for Nuclear Physics (Kazakhstan); Zhusupov, M. A.; Imambekov, O.; Sagindykov, Sh. Sh. [Al Farabi Kazakh National University (Kazakhstan)
A unified view of coherent and incoherent dihydrogen exchange in transition metal hydrides by nuclear resonance and inelastic neutron scattering
In this paper a unified view of coherent and incoherent dihydrogen exchange in transition metal hydrides by nuclear magnetic resonance (NMR) and inelastic neutron scattering (INS) is presented. It is shown that both exchange processes coexist i.e. do not transform into each other although they may dominate the spectra in different temperature ranges. This superposition is the consequence of the incorporation of the tunnel frequency J of the coherent process into the nuclear two-spin hamiltonian of hydrogen pairs which allows to treat the problem using the well known density matrix theory of NMR line-shapes developed by Alexander and Binsch. It is shown that this theory can also be used to predict the line-shapes of the rotational tunneling transitions observed in the INS spectra of transition metal dihydrogen complexes and that both NMR and INS spectra depend on similar parameters.
Limbach, H.H.; Ulrich, S.; Buntkowsky, G. [Freie Univ. Berlin (Germany). Inst. fuer Organische Chemie; Sabo-Etienne, S.; Chaudret, B. [Toulouse-3 Univ., 31 (France). Lab. de Chimie de Coordination du C.N.R.S.; Kubas, G.J.; Eckert, J. [Los Alamos National Lab., NM (United States)
A Measurement of the neutron electric form factor at very large momentum transfer using polaried electrions scattering from a polarized helium-3 target
Knowledge of the electric and magnetic elastic form factors of the nucleon is essential for an understanding of nucleon structure. Of the form factors, the electric form factor of the neutron has been measured over the smallest range in Q{sup 2} and with the lowest precision. Jefferson Lab experiment 02-013 used a novel new polarized {sup 3}He target to nearly double the range of momentum transfer in which the neutron form factor has been studied and to measure it with much higher precision. Polarized electrons were scattered off this target, and both the scattered electron and neutron were detected. G{sup n}{sub E} was measured to be 0.0242 � 0.0020(stat) � 0.0061(sys) and 0.0247 � 0.0029(stat) � 0.0031(sys) at Q{sup 2} = 1.7 and 2.5 GeV{sup 2}, respectively.
Aidan Kelleher
The quantum nature of the OH stretching mode in ice and water probed by neutron scattering experiments
The OH stretching vibrational spectrum of water was measured in a wide range of temperatures across the triple point, 269 K < T < 296 K, using Inelastic Neutron Scattering (INS). The hydrogen projected density of states and the proton mean kinetic energy, _OH, were determined for the first time within the framework of a harmonic description of the proton dynamics. We found that in the liquid the value of _OH is nearly constant as a function of T, indicating that quantum effects on the OH stretching frequency are weakly dependent on temperature. In the case of ice, ab initio electronic structure calculations, using non-local van der Waals functionals, provided _OH values in agreement with INS experiments. We also found that the ratio of the stretching (_OH) to the total (_exp) kinetic energy, obtained from the present measurements, increases in going from ice, where hydrogen bonding is the strongest, to the liquid at ambient conditions and then to the vapour phase, where hydrogen bonding is the weakest. The same ratio was also derived from the combination of previous deep inelastic neutron scattering data, which does not rely upon the harmonic approximation, and the present measurements. We found that the ratio of stretching to the total kinetic energy shows a minimum in the metastable liquid phase. This finding suggests that the strength of intermolecular interactions increases in the supercooled phase, with respect to that in ice, contrary to the accepted view that supercooled water exhibits weaker hydrogen bonding than ice.
Senesi, Roberto [ORNL; Flammini, Davide [ORNL; Kolesnikov, Alexander I [ORNL; Murray, Eamonn D. [University of California, Davis; Galli, Giulia [University of California, Davis; Andreani, Carla [ORNL
Science | ORNL Neutron Sciences
Neutron Science Neutron Science Neutron Scattering Science Neutrons are one of the fundamental particles that make up matter and have properties that make them ideal for certain types of research. In the universe, neutrons are abundant, making up more than half of all visible matter. Neutron scattering provides information about the positions, motions, and magnetic properties of solids. When a beam of neutrons is aimed at a sample, many neutrons will pass through the material. But some will interact directly with atomic nuclei and "bounce" away at an angle, like colliding balls in a game of pool. This behavior is called neutron diffraction, or neutron scattering. Using detectors, scientists can count scattered neutrons, measure their energies and the angles at which they scatter, and map their final position
Introduction to Neutron Spin Echo Spectroscopy
... Nuclear Interaction Neutrons are scattered by the nuclei. Scattering power varies �randomly� from isotope to isotope. ... segment dynamics hydro gels ...
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The Manuel Lujan, Jr. Neutron Scattering Center (LANSCE) experiment reports 1992 run cycle. Progress report
This year was the fifth in which LANSCE ran a formal user program. A call for proposals was issued before the scheduled run cycles, and experiment proposals were submitted by scientists from universities, industry, and other research facilities around the world. An external program advisory committee, which LANSCE shares with the Intense Pulsed Neutron Source (IPNS), Argonne National Laboratory, examined the proposals and made recommendations. At LANSCE, neutrons are produced by spallation when a pulsed, 800-MeV proton beam impinges on a tungsten target. The proton pulses are provided by the Clinton P. Anderson Meson Physics Facility (LAMPF) accelerator and an associated Proton Storage Ring (PSR), which can alter the intensity, time structure, and repetition rate of the pulses. The LAMPF protons of Line D are shared between the LANSCE target and the Weapons Neutron Research (WNR) facility, which results in LANSCE spectrometers being available to external users for unclassified research about 80% of each annual LAMPF run cycle. Measurements of interest to the Los Alamos National Laboratory may also be performed and may occupy up to an additional 20% of the available beam time. These experiments are reviewed by an internal program advisory committee. One hundred sixty-seven proposals were submitted for unclassified research and twelve proposals for research of a programmatic interest to the Laboratory; six experiments in support of the LANSCE research program were accomplished during the discretionary periods. Oversubscription for instrument beam time by a factor of three was evident with 839 total days requested and only 371 available for allocation.
DiStravolo, M.A. [comp.
SNS Instrument System Beam Lines | ORNL Neutron Sciences
SNS Instrument Beam Lines SNS Instrument Beam Lines This diagram shows the beam lines designated for currently funded instruments. Clicking on an instrument description will take you to the page for that instrument. Clicking anywhere else on the image will open a full-size, printable PDF file. SNS Instrument Layout Backscattering Spectrometer (BASIS) Disordered Materials Diffractometer (NOMAD) Wide Angular-Range Chopper Spectrometer (ARCS) Fine-Resolution Fermi Chopper Spectrometer (SEQUOIA) Coming Soon - Vibrational Spectrometer (VISION) Neutron Spin Echo (NSE) Hybrid Spectrometer (HYSPEC) Fundamental Neutron Physics Beamline (FNPB) Single Crystal Diffractometer (TOPAZ) Versatile Neutron Imaging Instrument (VENUS) Macromolecular Diffractometer (MaNDi) Powder Diffractometer (POWGEN3) Engineering Diffractometer (VULCAN) Extended Q-Range Small Angle Neutron Diffractometer (EQ-SANS) Cold Neutron Chopper Spectrometer (CNCS) Liquids (horizontal surface) Reflectometer (LR) Magnetic Advanced Grazing InCidence Spectrometer (MAGICS) High Pressure Diffractometer (SNAP) Coming Soon - Elastic Diffuse Scattering Spectrometer (CORELLI)
A small angle neutron scattering investigation of the kinetics of phase separation in an Fe-27. 5 at. % Cr-5. 6 at. % Ni alloy
The small angle neutron scattering has been investigated in situ at 450{degree} and 500{degree}C for a polycrystalline, duplex Fe-27.5 at. % Cr-5.6 at. % Ni steel. A broad diffuse maximum in the scattering function is the signature of the {alpha}{prime}-phase formation, and this maximum is superimposed on a strong, temperature-dependent component due to critical magnetic scattering. The time dependence of the shift in the peak intensity position to lower scattering vectors and the increase in peak intensity obey power law scaling behavior. Furthermore, the structure function exhibits dynamical scaling, after about three hours annealing. It is suggested that this behavior could be utilized to predict the microstructure, and hence some of the properties, after significantly longer annealing times. 21 refs., 3 figs.
Epperson, J.E. (Argonne National Lab., IL (USA)); Rainey, V.S.; Windsor, C.G. (UKAEA Atomic Energy Research Establishment, Harwell (UK). Materials Physics and Metallurgy Div.); Hawick, K.A. (Edinburgh Univ. (UK). Dept. of Physics); Chen, H. (Illinois Univ., Urbana, IL (USA). Dept. of Materials Science and Engineering)
For more information: Neutron Scattering Science User Office, email@example.com or (865) 574-4600.
of operat- ing temperatures. One type of nickel-based superalloy studied at HFIR is Waspaloy®.This heat Littrell, lead scientist for the GP-SANS instru- ment at HFIR, and Rosario Gerhardt and Ricky Whelchel and measurement times demonstrate that the GP-SANS system at HFIR is suitable for more complex ex- periments
Structure and dynamics of water adsorbed in carbon nanotubes : a joint neutron scattering and molecular-dynamics study.
The advent of nanocarbons, from single- and multiple-walled nanotubes to nanohorns, avails model studies of confined molecules on the nanoscale. Water encapsulated inside the quasi-one-dimensional channels of these materials is expected to exhibit anomalous behavior due to the unique geometry of nanotubes and the weak interaction between the water molecules and the carbon atoms. We have employed neutron small-to-wide angle diffraction, quasielastic and inelastic scattering in conjunction with molecular-dynamics simulations to characterize the structures and dynamics of water adsorbed in open-ended single- and double-walled nanotubes over a wide range of spatial and temporal scales. We find that a square-ice sheet wrapped next to the inner nanotube wall and a water chain in the interior are the key structural elements of nanotube-confined water/ice. This configuration results in a hydrogen-bond connectivity that markedly differs from that in bulk water. This significantly softened hydrogen-bond network manifests in strong energy shifts of the observed and simulated inter- and intra-molecular vibrations. The very large mean-square displacement of hydrogen atoms observed experimentally and the strong anharmonicity inferred from simulations explain the fluid-like behavior at temperatures far below the freezing point of normal water.
de Souza, N. R.; Kolesnikov, A. I.; Loong, C.-K.; Moravsky, A. P.; Loutfy, R. O.; Burnham, C. J.; Intense Pulsed Neutron Source; MER Corp.; Univ. of Utah
... Scattering Studies on Blends of Poly Jul 21 1 S. Krueger, Z. 6965 SANS Studies of DNA 10CB Krueger Kelman, K. Rubinson NIST Helicase and Its ...
Neutrons for Materials Science and Engineering - ASM Oak Ridge...
of NST2 Attendees Click for full Size Image Welcome Overview - Michelle Buchanon Fundamentals of Neutron Scattering Research - Ian Anderson Neutron Scattering on Magnetic...
The physics of photons and neutrons with applications of deuterium labeling methods to polymers
Over the past decade small-angle neutron scattering (SANS), has found numerous applications in the fields of biology, polymer science, physical chemistry, materials science, metallurgy, colloids, and solid state physics. A number of excellent references are available which contain basic neutron scattering theory though these text books reflect the origins of the technique and the examples are largely drawn from physics e.g., single crystals, simple liquids, monatomic gases, liquid metals, magnetic materials, etc. in view of the large numbers of nonspecialists who are increasingly using neutron scattering, the need has become apparent for presentations which can provide rapid access to the method without unnecessary detail and mathematical rigor. This article is meant to serve as a general introduction to the symposium ''Scattering Deformation and Fracture in Polymers,'' and is intended to aid potential users who have a general scientific background, but no specialist knowledge of scattering, to apply the technique to provide new information in areas of their own particular interests. In view of space limitations, the general theory will be given in the case for neutron scattering and analogies and differences with photon scattering (x-rays) will be pointed out at the appropriate point. 90 refs., 6 figs.
Wignall, G.D.
SANS Training Voucher Program Registration Procedures For Federal Employees/Contractors Process: Currently, under this program, the OCIO will cover only registration fees for SANS courses. All travel costs are the responsibility of the Federal Employee/Contractor's employing organization. Every effort must be made to complete classes within the allotted time frame. Extension of on-line courses may be granted by SANS; however, this expense is to be covered by the employing organization. The employing organization must also reimburse the OCIO fees for any registered course the student does not complete. In addition, the OCIO will not pay for certification. Costs for certification testing related to the training must be covered by the employee or employing organization and submitted to SANS directly, no through the OCIO
Analytical Calculation of the Neutrons Spectrum for Direct Measurement of N-N Scattering at Pulsed Reactor Yaguar
Analytical calculation of a single neutron detector counts per YAGUAR reactor pulse is presented and comparison with coincidence scheme is given.
V. K. Ignatovich
Procurement - ORNL Neutron Sciences
for the acquisition of goods and services for neutron scattering operations at SNS and HFIR. If you're interested in conducting business with the Neutron Sciences Directorate or...
Neutron Scattering and Dynamics
... "Molecule" H2O (N2)0.8(O2)0.2 Al Cd sigma_s barn 168.3 20.1 1.5 6.5 ... 31 Collective dynamics Animation courtesy of A. Zheludev (ORNL) ...
Dynamics and Neutron Scattering
... energy window ... if there is more than one isotope and/or nonzero nuclear ... Comparisons with theory and/or computer simulations are commonly ...
Neutron Scattering Conferences
8-12, 2013 International Workshop: Powder & Electron Crystallography Location Patras, Greece Contact Partha Pratim Das Email firstname.lastname@example.com URL http:crystallographypatras.wor...
Neutron Activation Calculator
... and incoherent scattering cross sections). Source neutrons (Ang, meV or m/s), Density (g/cm 3 or lattice), Thickness (cm). ...
Matter Physics Neutron Scattering in Quantum Condensed Matter Physics flyer The first cyber enabled collaborative graduate course was launched in Fall semester 2012. It addresses...
Materials Division Oak Ridge National Laboratory Phone: 865.241.5176 SNS Logo HFIR Logo General Information The unique potential of neutron scattering in structural...
Test of the consistency of various linearized semiclassical initial value time correlation functions in application to inelastic neutron scattering from liquid para-hydrogen
The linearized approximation to the semiclassical initial value representation (LSC-IVR) is used to calculate time correlation functions relevant to the incoherent dynamic structure factor for inelastic neutron scattering from liquid para-hydrogen at 14 K. Various time correlations functions were used which, if evaluated exactly, would give identical results, but they do not because the LSC-IVR is approximate. Some of the correlation functions involve only linear operators, and others involve non-linear operators. The consistency of the results obtained with the various time correlation functions thus provides a useful test of the accuracy of the LSC-IVR approximation and its ability to treat correlation functions involving both linear and nonlinear operators in realistic anharmonic systems. The good agreement of the results obtained from different correlation functions, their excellent behavior in the spectral moment tests based on the exact moment constraints, and their semi-quantitative agreement with the inelastic neutron scattering experimental data all suggest that the LSC-IVR is indeed a good short-time approximation for quantum mechanical correlation functions.
Miller, William; Liu, Jian; Miller, William H.
HFIR Instrument Systems | ORNL Neutron Sciences
Click for more information about the HFIR beamline Experiment Hall Click for more information about the HFIR beamline Experiment Hall HFIR instrument layout. Click for details. Instruments at the High Flux Isotope Reactor The instrument suite at HFIR is supported by a variety of sample environments and on-site laboratories for user convenience. If you're unsure which instrument(s) would most benefit your research, or if you would like to request capabilities that you don't see here, please contact our user office. All HFIR Instrument fact sheets are also available in this single PDF document. Available to Users Beam Line Fact Sheet Instrument Name Contact CG-1 Development Beam Line Lee Robertson CG-1D PDF IMAGING - Neutron Imaging Prototype Facility Hassina Bilheux CG-2 PDF GP-SANS - General-Purpose Small-Angle Neutron Scattering Diffractometer Ken Littrell
Proceedings of the Oak Ridge National Laboratory/Brookhaven National Laboratory workshop on neutron scattering instrumentation at high-flux reactors
For the first three decades following World War II, the US, which pioneered the field of neutron scattering research, enjoyed uncontested leadership in the field. By the mid-1970's, other countries, most notably through the West European consortium at Institut Laue-Langevin (ILL) in Grenoble, France, had begun funding neutron scattering on a scale unmatched in this country. By the early 1980's, observers charged with defining US scientific priorities began to stress the need for upgrading and expansion of US research reactor facilities. The conceptual design of the ANS facility is now well under way, and line-item funding for more advanced design is being sought for FY 1992. This should lead to a construction request in FY 1994 and start-up in FY 1999, assuming an optimal funding profile. While it may be too early to finalize designs for instruments whose construction is nearly a decade removed, it is imperative that we begin to develop the necessary concepts to ensure state-of-the-art instrumentation for the ANS. It is in this context that this Instrumentation Workshop was planned. The workshop touched upon many ideas that must be considered for the ANS, and as anticipated, several of the discussions and findings were relevant to the planning of the HFBR Upgrade. In addition, this report recognizes numerous opportunities for further breakthroughs on neutron instrumentation in areas such as improved detection schemes (including better tailored scintillation materials and image plates, and increased speed in both detection and data handling), in-beam monitors, transmission white beam polarizers, multilayers and supermirrors, and more. Each individual report has been cataloged separately.
McBee, M.R. (ed.); Axe, J.D.; Hayter, J.B.
Neutron Imaging of Hydrogen in Steels
Symposium, Applied Neutron Scattering in Engineering and Materials Science Research. Presentation Title, Neutron Imaging of Hydrogen in Steels. Author(s)�...
Data Management Practices | ORNL Neutron Sciences
to data generated from neutron scattering experiments at the High Flux Isotope Reactor (HFIR) and the Spallation Neutron Source (SNS). Any changes to these guidelines will be...
Coal Pores: Greenhouse Gases and Coal Pores: Greenhouse Gases and Methane Energy and Environmental Solutions Under Our Feet Mix of neutron scattering techniques helps resolve critical problems of confining greenhouse gases and extracting methane Research Contact: Yuri Melnichenko August 2011, Written by Agatha Bardoel Yuri Melnichenko at the GPSANS instrument GP-SANS instrument scientist Yuri Melnichenko (left) and postdoctoral associate Lilin He. When you heat water in a kettle, you can make tea or coffee. But what happens if the vessel is sealed? Ultimately, at a temperature called the liquid-gas critical point, the density of the liquid and the vapor become identical: There is no more water, there is no more gas. What you have is a supercritical fluid. The phenomenon of liquid-liquid and liquid-gas coexistence was a
Structural hierarchy of chromatin in chicken erythrocyte nuclei based on small-angle neutron scattering: Fractal nature of the large-scale chromatin organization
The chromatin organization in chicken erythrocyte nuclei was studied by small-angle neutron scattering in the scattering-vector range from 1.5 x 10{sup -1} to 10{sup -4} A{sup -1} with the use of the contrast-variation technique. This scattering-vector range corresponds to linear dimensions from 4 nm to 6 {mu}m and covers the whole hierarchy of chromatin structures, from the nucleosomal structure to the entire nucleus. The results of the present study allowed the following conclusions to be drawn: (1) both the chromatin-protein structure and the structure of the nucleic acid component in chicken erythrocyte nuclei have mass-fractal properties, (2) the structure of the protein component of chromatin exhibits a fractal behavior on scales extending over two orders of magnitude, from the nucleosomal size to the size of an entire nucleus, and (3) the structure of the nucleic acid component of chromatin in chicken erythrocyte nuclei is likewise of a fractal nature and has two levels of organization or two phases with the crossover point at about 300-400 nm.
Lebedev, D. V., E-mail: email@example.com; Filatov, M. V. [Russian Academy of Sciences, Petersburg Nuclear Physics Institute (Russian Federation); Kuklin, A. I.; Islamov, A. Kh. [Joint Institute of Nuclear Research (Russian Federation); Stellbrink, J. [Research Centre Juelich (Germany); Pantina, R. A.; Denisov, Yu. Yu.; Toperverg, B. P.; Isaev-Ivanov, V. V. [Russian Academy of Sciences, Petersburg Nuclear Physics Institute (Russian Federation)
Clifford G. Shull, Neutron Diffraction, Hydrogen Atoms, and Neutron
Office of Scientific and Technical Information (OSTI)
Clifford Shull, Neutron Diffraction, and Neutron Scattering Clifford Shull, Neutron Diffraction, and Neutron Scattering Resources with Additional Information Clifford G. Shull was awarded the 1994 Nobel Prize in Physics "for the development of the neutron diffraction technique". 'Professor Shull's prize was awarded for his pioneering work in neutron scattering, a technique that reveals where atoms are within a material like ricocheting bullets reveal where obstacles are in the dark. Clifford Shull Photo Courtesy of Oak Ridge National Laboratory When a beam of neutrons is directed at a given material, the neutrons bounce off, or are scattered by, atoms in the sample being investigated. The neutrons' directions change, depending on the location of the atoms they hit, and a diffraction pattern of the atoms' positions can then be obtained.
A system for differential neutron scattering experiments in the energy range from 0.5 to 20 MeV
piece of depleted uranium was used to attenuate the intense gamma flash. With the sample placed for the experiment. To eliminate gamma flash associated recovery issues, 2.54 cm (1 in.) of depleted uranium, the neutron flux was measured through a one inch thick piece of depleted uranium. By a simple calculation
Level crossings and zero-field splitting in the {Cr8}-cubane spin-cluster studied using inelastic neutron scattering and magnetization
Inelastic neutron scattering (INS) in variable magnetic field and high-field magnetization measurements in the millikelvin temperature range were performed to gain insight into the low-energy magnetic excitation spectrum and the field-induced level crossings in the molecular spin cluster {Cr8}-cubane. These complementary techniques provide consistent estimates of the lowest level-crossing field. The overall features of the experimental data are explained using an isotropic Heisenberg model, based on three distinct exchange interactions linking the eight CrIII paramagnetic centers (spins s = 3/2), that is supplemented with a relatively large molecular magnetic anisotropy term for the lowest S = 1 multiplet. It is noted that the existence of the anisotropy is clearly evident from the magnetic field dependence of the excitations in the INS measurements, while the magnetization measurements are not sensitive to its effects.
Vaknin, D. [Ames Laboratory; Garlea, Vasile O [ORNL; Demmel, F. [ISIS Facility, Rutherford Appleton Laboratory; Mamontov, Eugene [ORNL; Nojiri, H [Institute for Materials Research, Tohoku University, Sendai, Japan; Martin, Catalin [Florida State University; Chiorescu, Irinel [Florida State University; Qiu, Y. [National Institute of Standards and Technology (NIST); Luban, M. [Ames Laboratory; Kogerler, P. [Ames Laboratory; Fielden, J. [Ames Laboratory; Engelhardt, L [Francis Marion University, Florence, South Sarolina; Rainey, C [Francis Marion University, Florence, South Sarolina
A New Control System Software for SANS BATAN Spectrometer in Serpong, Indonesia
The original main control system of the 36 meter small-angle neutron scattering (SANS) BATAN Spectrometer (SMARTer) has been replaced with the new ones due to the malfunction of the main computer. For that reason, a new control system software for handling all the control systems was also developed in order to put the spectrometer back in operation. The developed software is able to control the system such as rotation movement of six pinholes system, vertical movement of four neutron guide system with the total length of 16.5 m, two-directional movement of a neutron beam stopper, forward-backward movement of a 2D position sensitive detector (2D-PSD) along 16.7 m, etc. A Visual Basic language program running on Windows operating system was employed to develop the software and it can be operated by other remote computers in the local area network. All device positions and command menu are displayed graphically in the main monitor or window and each device control can be executed by clicking the control button. Those advantages are necessary required for developing a new user-friendly control system software. Finally, the new software has been tested for handling a complete SANS experiment and it works properly.
Bharoto; Putra, Edy Giri Rachman [Neutron Scattering Laboratory, Center for Technology of Nuclear Industrial Materials, National Nuclear Energy Agency of Indonesia (BATAN) Gedung 40, Kawasan Puspiptek Serpong, Tangerang 15314 (Indonesia)
Diffusion and adsorption of methane confined in nanoporous carbon aerogel: a combined quasi-elastic and small-angle neutron scattering study
The diffusion of methane confined in nano-porous carbon aerogel with the average pore size 48 {angstrom} and porosity 60% was investigated as a function of pressure at T = 298 K using quasi-elastic neutron scattering (QENS). The diffusivity of methane shows a clear effect of confinement: it is about two orders of magnitude lower than in bulk at the same thermodynamic conditions and is close to the diffusivity of liquid methane at 100 K (i.e. {approx} 90 K below the liquid-gas critical temperature T{sub C} {approx} 191 K). The diffusion coefficient (D) of methane initially increases with pressure by a factor of {approx}2.5 from 3.47 {+-} 0.41 x 10{sup -10} m{sup 2} s{sup -1} at 0.482 MPa to D = 8.55 {+-} 0.33 x 10{sup -10} m{sup 2} s{sup -1} at 2.75 MPa and starts to decrease at higher pressures. An explanation of the observed non-monotonic behavior of the diffusivity in the confined fluid is based on the results of small-angle neutron scattering experiments of the phase behavior of methane in a similar carbon aerogel sample. The initial increase of the diffusion coefficient with pressure is explained as due to progressive filling of bigger pores in which molecular mobility in the internal pore volume is less affected by the sluggish liquid-like molecular mobility in the adsorbed phase. Subsequent decrease of D, is associated with the effect of intermolecular collisions, which result in a lower total molecular mobility with pressure, as in the bulk state. The results are compared with the available QENS data on the methane diffusivity in zeolites, metal organic frameworks, and porous silica as well as with the molecular dynamics simulations of methane in nano-porous carbons and silica zeolites.
Mavila Chathoth, Suresh [ORNL; Mamontov, Eugene [ORNL; Melnichenko, Yuri B [ORNL; Zamponi, Michaela M [ORNL
Dzyaloshinsky-Moriya interaction and long life time of the spin state in the Cu$_3$ triangular spin cluster by inelastic neutron scattering measurements
Inelastic neutron scattering (INS) experiments have been performed on the Cu$_3$ triangular molecular nanomagnet using powder samples. In the medium resolution INS spectrum measured, there are two peaks at $\\hbar\\omega=0.5$ and 0.6 meV. Comparing the observed $Q$ dependences of these peaks with calculations, these two INS peaks originate from the Cu$_3$ cluster. From the observed peak position, width, and intensity, we have determined the optimum parameters of the spin Hamiltonian consisted of the antiferromagnetic exchange and the Dzyaloshinsky-Moriya interactions, which can also reproduce the magnetic susceptibility measurement. In addition, we have directly observed that the ground state quartet is split into two doublets with the energy separation of 0.103 meV using high-resolution neutron spectroscopy, which exactly corresponds to that expected from the optimum parameters obtained from the medium resolution xperiment. The temperature dependences of the integrated intensities of the 0.5 and 0.6 meV peaks are well reproduced by the Boltzmann distribution of the energy levels of the model Hamiltonian below 10 K. Furthermore, the inelastic peaks were visible even at very high temperatures as 50 K. This indicates extraordinary weak coupling between phonons (or any other perturbations) and spin states in the Cu$_3$ cluster, compared to the other known molecular nanomagnets.
Kazuki Iida; Yiming Qiu; Taku J Sato
SANS Study of Cellulose Extracted from Switchgrass
AbstractLignocellulosic biomass, an abundant renewable natural resource, has the potential to play a major role in generation of renewable biofuels through its conversion to bio-ethanol. Unfortunately, it is a complex biological composite material that shows significant recalcitrance making it a cost-ineffective feedstock for bioethanol production. Small-angle neutron scattering (SANS) was employed to probe the multi-scale structure of cellulosic materials. Cellulose was extracted from milled native switchgrass and switchgrass that had undergone the dilute acid pretreatment method to disrupt the lignocellulose structure. The high-Q structural feature (Q > 0.07 -1) can be assigned to cellulose fibrils based on comparison with the switchgrass purified by solvent extraction of native and dilute acid pretreated and a commercial preparation of microcrystalline cellulose. Dilute acid pretreatment results in an increase in the smallest structural size, a decrease in the interconnectivity of the fibrils; and no change in the smooth domain boundaries at length scales larger than 1000 .
Pingali, Sai Venkatesh [ORNL; Urban, Volker S [ORNL; Heller, William T [ORNL; McGaughey, Joseph [ORNL; O' Neill, Hugh Michael [ORNL; Foston, Marcus B [ORNL; Myles, Dean A A [ORNL; Ragauskas, Arthur J [ORNL; Evans, Barbara R [ORNL
Search for the First-Order Liquid-to-Liquid Phase Transition in Low-Temperature Confined Water by Neutron Scattering
It has been conjectured that a 1st order liquid-to-liquid (L-L) phase transition (LLPT) between high density liquid (HDL) and low density liquid (LDL) in supercooled water may exist, as a thermodynamic extension to the liquid phase of the 1st order transition established between the two bulk solid phases of amorphous ice, the high density amorphous ice (HDA) and the low density amorphous ice (LDA). In this paper, we first recall our previous attempts to establish the existence of the 1st order L-L phase transition through the use of two neutron scattering techniques: a constant Q elastic diffraction study of isobaric temperature scan of the D2O density, namely, the equation of state (EOS) measurements. A pronounced density hysteresis phenomenon in the temperature scan of the density above P = 1500 bar is observed which gives a plausible evidence of crossing the 1st order L-L phase transition line above this pressure; an incoherent quasi-elastic scattering measurements of temperature-dependence of the alpha-relaxation time of H2O at a series of pressures, namely, the study of the Fragile-to-Strong dynamic crossover (FSC) phenomenon as a function of pressure which we interpreted as the results of crossing the Widom line in the one-phase region. In this new experiment, we used incoherent inelastic neutron scattering (INS) to measure the density of states (DOS) of H atoms in H2O molecules in confined water as function of temperature and pressure, through which we may be able to follow the emergence of the LDL and HDL phases at supercooled temperature and high pressures. We here report for the first time the differences of librational and translational DOSs between the hypothetical HDL and LDL phases, which are similar to the corresponding differences between the well-established HDA and LDA ices. This is plausible evidence that the HDL and LDL phases are the thermodynamic extensions of the corresponding amorphous solid water HDA and LDA ices.
Chen, Sow-Hsin [Massachusetts Institute of Technology (MIT); Wang, Zhe [Massachusetts Institute of Technology (MIT); Kolesnikov, Alexander I [ORNL; Zhang, Yang [ORNL; Liu, Kao-Hsiang [National Taiwan University
Pulsed-neutron monochromator
In one aspect, the invention is an improved pulsed-neutron monochromator of the vibrated-crystal type. The monochromator is designed to provide neutron pulses which are characterized both by short duration and high density. A row of neutron-reflecting crystals is disposed in a neutron beam to reflect neutrons onto a common target. The crystals in the row define progressively larger neutron-scattering angles and are vibrated sequentially in descending order with respect to the size of their scattering angles, thus generating neutron pulses which arrive simultaneously at the target. Transducers are coupled to one end of the crystals to vibrate them in an essentially non-resonant mode. The transducers propagate transverse waves in the crystal which progress longitudinally therein. The waves are absorbed at the undriven ends of the crystals by damping material mounted thereon. In another aspect, the invention is a method for generating neutron pulses characterized by high intensity and short duration.
Mook, H.A. Jr.
... oxide) in Maryland)+ D Ho Water/ethanol mixtures Nov 7 3 J ... N. 13598 UD Scattering Class Lab 10CB Butler ... C Nov 18 1 SANS Staff (12 Feasibility ...
A nuclear reactor for isotope production is described. This reactor is designed to provide a maximum thermal neutron flux in a region adjacent to the periphery of the reactor rather than in the center of the reactor. The core of the reactor is generally centrally located with respect tn a surrounding first reflector, constructed of beryllium. The beryllium reflector is surrounded by a second reflector, constructed of graphite, which, in tune, is surrounded by a conventional thermal shield. Water is circulated through the core and the reflector and functions both as a moderator and a coolant. In order to produce a greatsr maximum thermal neutron flux adjacent to the periphery of the reactor rather than in the core, the reactor is designed so tbat the ratio of neutron scattering cross section to neutron absorption cross section averaged over all of the materials in the reflector is approximately twice the ratio of neutron scattering cross section to neutron absorption cross section averaged over all of the material of the core of the reactor.
Wigner, E.P.
Neutron Physics at NIST 8th UCN Workshop
The Neutron Scattering Society of America www.neutronscattering.org Press Release, February 4, 2008 The Neutron Scattering Society of America is pleased to announce the 2008 recipients of its 3 major prizes. The Neutron Scattering Society of America (NSSA) established the Clifford G. Shull Prize in Neutron Science
Titov, Anatoly
BASIS Highlights | ORNL Neutron Sciences
in water and other glass-forming liquids, covering six research collaborations at ORNL Neutron scattering provides window into surface interactions High-performance...
reveals semiconducting phase and contributes to new understanding of iron-based superconductors Contact: Huibo Cao Neutron scattering measures samples too hot to hold Contact:...
Neutron Science and Supercomputing Come Together at Oak Ridge...
Neutron Science and Supercomputing Come Together at Oak Ridge National Lab (HPCWire) June 24, 2013 Next-generation neutron scattering requires next-generation data analysis...
Hazard Analysis for the High Power Accelerator Production of Tritium (APT) Experiments at the Los Alamos Neutron Scattering Center (LANSCE).
The Accelerator Production of Tritium (APT) Target/Blanket and Materials Engineering Demonstration and Development (ED and D) Project has undertaken a major program of high-power materials irradiation at the Los Alamos Neutron Science Center (LANSCE) Accelerator. Five experiments have been installed in the Target A-6 area, immediately before the Isotope Production facility and the LANSCE bearnstop, where they will take a 1.0-mAmp-proton beam for up to 10 months. This operation is classed as a Nuclear Category (cat)-3 activity, since enough radionuclides buildup in the path of tie beam to exceed cat-3 threshold quantities. In the process of analyzing this buildup, it was realized that a loss of coolant accident (LOCA) could result in oxidation and subsequent vaporization of certain tungsten elements contained in our experiments. If this process occurs in the presence of steam, breakup of the water molecule would also provide a potentially explosive source of hydrogen, causing maximum release of radioactive aerosols to the surrounding environment. This process can occur in a matter of seconds. Such a release would result in potentially unacceptable dose to the public at the LANSCE site boundary, 800 meters from the A-6 area.
Waters, L.S.
Dynamics of quantum spin liquid and spin solid phases in IPA-CuCl3 under an applied magnetic field studied with neutron scattering
Inelastic and elastic neutron scattering is used to study spin correlations in the quasi-one-dimensional quantum antiferromagnet IPA-CuCl3 in strong applied magnetic fields. A condensation of magnons and commensurate transverse long-range ordering is observe at a critical field Hc=9.5 T. The field dependencies of the energies and polarizations of all magnon branches are investigated both below and above the transition point. Their dispersion is measured across the entire one-dimensional Brillouin zone in magnetic fields up to 14 T. The critical wave vector of magnon spectrum truncation Masuda et al., Phys. Rev. Lett. 96, 047210 2006 is found to shift from hc0,35 at HHC to hc=0.25 for HHC. A drastic reduction of magnon bandwidths in the ordered phase Garlea et al., Phys. Rev. Lett. 98, 167202 2007 is observed and studied in detail. New features of the spectrum, presumably related to this bandwidth collapse, are observed just above the transition field.
Zheludev, Andrey I [ORNL; Garlea, Vasile O [ORNL; Masuda, T. [Yokohama City University, Japan; Manaka, H. [Kagoshima University, Kagoshima JAPAN; Regnault, L.-P. [CEA, Grenoble, France; Ressouche, E. [CEA, Grenoble, France; Grenier, B. [CEA, Grenoble, France; Chung, J.-H. [National Institute of Standards and Technology (NIST); Qiu, Y. [National Institute of Standards and Technology (NIST); Habicht, Klaus [Hahn-Meitner Institut, Berlin, Germany; Kiefer, K. [Hahn-Meitner Institut, Berlin, Germany; Boehm, Martin [Institut Laue-Langevin (ILL)
ORNL Neutron Sciences Users
SHUG banner SNS-HFIR User Group The SNS-HFIR User Group (SHUG) consists of all persons interested in using the neutron scattering facilities at Oak Ridge. It provides input to the...
Characterization of Tight Gas Reservoir Pore Structure Using USANS/SANS and Gas Adsorption Analysis
Small-angle and ultra-small-angle neutron scattering (SANS and USANS) measurements were performed on samples from the Triassic Montney tight gas reservoir in Western Canada in order to determine the applicability of these techniques for characterizing the full pore size spectrum and to gain insight into the nature of the pore structure and its control on permeability. The subject tight gas reservoir consists of a finely laminated siltstone sequence; extensive cementation and moderate clay content are the primary causes of low permeability. SANS/USANS experiments run at ambient pressure and temperature conditions on lithologically-diverse sub-samples of three core plugs demonstrated that a broad pore size distribution could be interpreted from the data. Two interpretation methods were used to evaluate total porosity, pore size distribution and surface area and the results were compared to independent estimates derived from helium porosimetry (connected porosity) and low-pressure N{sub 2} and CO{sub 2} adsorption (accessible surface area and pore size distribution). The pore structure of the three samples as interpreted from SANS/USANS is fairly uniform, with small differences in the small-pore range (< 2000 {angstrom}), possibly related to differences in degree of cementation, and mineralogy, in particular clay content. Total porosity interpreted from USANS/SANS is similar to (but systematically higher than) helium porosities measured on the whole core plug. Both methods were used to estimate the percentage of open porosity expressed here as a ratio of connected porosity, as established from helium adsorption, to the total porosity, as estimated from SANS/USANS techniques. Open porosity appears to control permeability (determined using pressure and pulse-decay techniques), with the highest permeability sample also having the highest percentage of open porosity. Surface area, as calculated from low-pressure N{sub 2} and CO{sub 2} adsorption, is significantly less than surface area estimates from SANS/USANS, which is due in part to limited accessibility of the gases to all pores. The similarity between N{sub 2} and CO{sub 2}-accessible surface area suggests an absence of microporosity in these samples, which is in agreement with SANS analysis. A core gamma ray profile run on the same core from which the core plug samples were taken correlates to profile permeability measurements run on the slabbed core. This correlation is related to clay content, which possibly controls the percentage of open porosity. Continued study of these effects will prove useful in log-core calibration efforts for tight gas.
Clarkson, Christopher R [ORNL; He, Lilin [ORNL; Agamalian, Michael [ORNL; Melnichenko, Yuri B [ORNL; Mastalerz, Maria [Indiana Geological Survey; Bustin, Mark [University of British Columbia, Vancouver; Radlinski, Andrzej Pawell [ORNL; Blach, Tomasz P [ORNL
San Diego Bay Bibliography
SDGE power plant; bay ABSTRACT: The marine organisms ofMarine Research KEYWORDS: San Diego Bay; programs; bay South Bay PowerMarine Organisms of South San Diego Bay and the Ecological Effects of Power
Brueggeman, Peter
Neutron Detection Efficiency of the
on improving the physical model used for neutron scattering in the resonance region. In many cases, the physical model for neutron scattering must take into account the motion of the target nuclei [2International Conference on Mathematics, Computational Methods & Reactor Physics (M&C 2009
Gilfoyle, Jerry
Neutron Scattering Graduate Programs | ORNL Neutron Sciences
at ORNL and the higher education sector. A major focus has been on the development of cyber-enabled collaborative graduate courses with participation from multiple university and...
Neutron Scattering Portal | ORNL Neutron Sciences
services can be accessed through the User Portal. Helpful web links to other useful ORNL sites are also available via the portal. Getting Access to Resources Our computing...
Neutron Scattering User Program | Neutron Science | ORNL
through programs such as internships and postdoctoral programs. The instruments at HFIR and SNS can be used free of charge with the understanding that researchers will publish...
Neutron Diffraction Study of Crystal Structure and Magnetic ...
Abstract Scope, Magnetic refrigeration based on the magnetocaloric effect ... Small and Wide Angle Neutron Scattering for Industrial Applications at HANARO.
SANS Training Voucher Program Registration Procedures | Department...
SANS Training Voucher Program Registration Procedures SANS Training Voucher Program Registration Procedures SANS Training Voucher Program Registration Procedures For Federal...
Compact D-D/D-T neutron generators and their applications
cold neutrons have an excellent resolution for the fusion-the fusion-based neutron source is more suitable for coldCold neutron source for Small Angle Neutron Scattering51 5.4 Summary of fusion-
Lou, Tak Pui
Supercool Neutrons (Ultracold Neutrons)
in the USA. Why neutrons? Neutrons possess physical properties that make them valuable investigative tools Spallation Neutron Source (SNS) The world's most intense pulsed accelerator-based neutron source. High Flux Isotope Reactor (HFIR) The highest flux reactor-based neutron source for condensed matter research
Martin, Jeff
EEE 562 Nuclear Reactor Theory and Design (3 hrs) Catalog Description: Principles of neutron chain reacting systems. Neutron diffusion and moderation.
important part of reactor physics. As the neutrons are produced in neutron induced fission of a fissile physical processes like neutron capture, elastic and inelastic scattering, upscattering, etc. Neutron technique is a scattering of free neutrons by matter. It is used in biophysics, physics, chemistry
Using Neutrons to Study Radioactive Materials
Symposium, Applied Neutron Scattering in Engineering and Materials Science Research ... to the unique infrastructure and specialized staff of the Nuclear Laboratory. Shielded cells enable neutron diffraction studies on highly radioactive�...
Neutron scattering and hydrogenous materials
... The next molecules, shown in brown, reside above the line defined by adjacent oxygen atoms, and in the sites above the benzene ring, shown in ...
NXS 2012 - Neutron Scattering School
ANL Facilities ANL Map (jpg) ANL Map (pdf) ANL Visitor's Guide ORNL Facilities HFIR Facility SNS Facility HFIRSNS Map Wireless Networks ORNL Safety & Security Rules ORNL...
NXS 2011 - Neutron Scattering School
NotesVideos Experiments ANL Facilities ANL Map ANL Visitor's Guide ORNL Facilities HFIR Facility SNS Facility HFIRSNS Map Wireless Networks ORNL Safety & Security Rules ORNL...
Neutron Scattering School (NXS2008)
Agenda updated 93008 Experiment Groups ORNL Experiments Experiments ORNL Facilities HFIR Facility SNS Facility HFIRSNS Map Access Requirements Wireless Network Access Rules &...
Neutron Scattering School (NXS2009)
Experiments Abstracts Discussion Schedule Experiments Experiment Groups ORNL Facilities HFIR Facility SNS Facility HFIRSNS Map Access Requirements Wireless Network Access Safety &...
Industry - ORNL Neutron Sciences
Industry banner Industry banner Neutron scattering research has applications in practically every field, and neutron research at ORNL is leading to productive partnerships with the industrial and business communities. We welcome proposals for all types of research, including those involving proprietary work. Recent studies have led to discoveries with potential applications in fields such as medicine, energy, and various metals technologies. For more information, please see our recent research highlights. Research Collaborations Industry-Driven Research Benefits Plastics Manufacturing Corning uses VULCAN to test limits of ceramic material for car emission controls, filtration devices Neutrons Probe Inner Workings of Batteries Industry and Neutron Science: Working To Make a Match
Quantum Condensed Matter | Neutron Science | ORNL
Quantum Condensed Matter SHARE Quantum Condensed Matter Neutron scattering is a uniquely powerful probe for measuring the structure and dynamics of condensed matter. As such it is...
Filter-Analyzer Neutron Spectrometer (FANS)
... J. Hwang, "Probing the Unusual Proton and Anion Mobility of LiBH ... Analysis of the Inelastic Neutron Scattering Spectra of Electron Donor-Acceptor ...
... Soc., Div. Fuel Chem ... H. Kabbour, and CC Ahn, "Hydrogen Adsorption in MOF-74 Studied by Inelastic Neutron Scattering", in Life Cycle Analysis for ...
Neutron Data Analysis & Visualization | More Science | ORNL
the data sets generated by the increasingly powerful neutron scattering instruments at HFIR and SNS grow ever more massive, the facilities' users require significant advances in...
ORNL Neutron Sciences Instrument Fact Sheets
of each neutron scattering instrument at ORNL. You can also view SNS Instrument and HFIR Instrument pages that go to the related instrument's web pages. Detailed information...
Quantum Condensed Matter Division | Neutron Science | ORNL
instruments used for diffraction and inelastic neutron scattering at both SNS and HFIR. The science conducted by our staff members emphasizes materials with emergent...
SANS Publications - 2012
... 45, Porosity of coal and shale: Insights from gas adsorption and SANS/USANS techniques, M. Mastalerz, L. He, YB Melnichenko, JA Rupp, Energy & ...
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
Dr. Andrey Podlesnyak | ORNL Neutron Sciences
Andrey Podlesnyak Andrey Podlesnyak Dr. Andrey Podlesnyak Instrument Scientist: Cold Neutron Chopper Spectrometer (CNCS), SNS Education PhD in Physics, Institute for Metal Physics, Ekaterinburg, Russia Description of Research 2008 - present Instrument Scientist, Cold Neutron Chopper Spectrometer, Neutron Scattering Sciences Division, Oak Ridge National Laboratory 2006 - 2008 Instrument Scientist, single crystal diffractometer E-4, Hahn-Meitner-Institut, Berlin, Germany 2002 - 2006 Instrument Scientist, TOF spectrometer FOCUS, Laboratory for Neutron Scattering, ETH Zurich & Paul Scherrer Institute, Switzerland 2000 - 2002 Instrument Scientist, triple-axis spectrometer TASP, Laboratory for Neutron Scattering, ETH Zurich & Paul Scherrer Institute, Switzerland 1994 - 2000 Physicist, Institute for Metal Physics, Ekaterinburg, Russia
SNS | Spallation Neutron Source | ORNL
SNS SNS Instruments Working with SNS Contact Us User Program Manager Laura Morris Edwards 865.574.2966 Spallation Neutron Source Home | User Facilities | SNS SNS | Spallation Neutron Source SHARE SNS is an accelerator-based neutron source in Oak Ridge, Tennessee, USA. This one-of-a-kind facility provides the most intense pulsed neutron beams in the world for scientific research and industrial development. The 80-acre SNS site is located on Chestnut Ridge and is part of Oak Ridge National Laboratory. Although most people don't know it, neutron scattering research has a lot to do with our everyday lives. For example, things like medicine, food, electronics, and cars and airplanes have all been improved by neutron scattering research. Neutron research also helps scientists improve materials used in a
Neutron sources and applications
Review of Neutron Sources and Applications was held at Oak Brook, Illinois, during September 8--10, 1992. This review involved some 70 national and international experts in different areas of neutron research, sources, and applications. Separate working groups were asked to (1) review the current status of advanced research reactors and spallation sources; and (2) provide an update on scientific, technological, and medical applications, including neutron scattering research in a number of disciplines, isotope production, materials irradiation, and other important uses of neutron sources such as materials analysis and fundamental neutron physics. This report summarizes the findings and conclusions of the different working groups involved in the review, and contains some of the best current expertise on neutron sources and applications.
Price, D.L. [ed.] [Argonne National Lab., IL (United States); Rush, J.J. [ed.] [National Inst. of Standards and Technology, Gaithersburg, MD (United States)
San Luis Transmission Project
Luis Transmission Project EIS/EIR Luis Transmission Project EIS/EIR San Luis Transmission Project EIS/EIR Western proposes to construct, own, operate, and maintain a new 230-kilovolt transmission line about 62 miles in length between Western's Tracy Substation and Western's San Luis Substation and a new 70-kV transmission line about 5 miles in length between the San Luis and O'Neill Substations. Western also will consider other transmission construction options including: A new 500-kV transmission line about 62 miles in length operated at 230-kV between Western's Tracy and San Luis Substations; A new 500-kV transmission line operated at 500-kV about 62 miles in length between the Tracy Substation and Pacific Gas and Electric's Los Banos Substation; and A new 230-kV transmission line about 18 miles in length between San Luis Substation and Dos Amigos Substation.
COUNTY OF SAN DIEGO Energy Upgrade San Diego
) $ 60,250 San Diego Co. Water Authority (building owner incentives) $ 150,000 San Diego EnergySoft CalCerts, Inc. Strategic Energy Innovations Manpower CBPCA Partnering Clean EnergyCOUNTY OF SAN DIEGO Energy Upgrade San Diego Summary Sheet ARRA EECBG Discretionary Funding
Neutron Data Analysis and Visualization Division - ORNL Neutron...
develops software and hardware for the reduction and analysis of data taken on SNS and HFIR neutron scattering instruments. We work closely with the SNS and HFIR Data Acquisition...
... and 9P Butler Greenberg (U. SC9-14 Linear Chains Akron) Jul 21 1 J. Trewhella + S. 805 Neutron Scattering 10CB Kline Gallagher (LANL) SC9-01 ...
particles of her milk using small-angle neutron scattering at ORNL's High Flux Isotope Reactor (HFIR). Casein micelles, a family of related phosphorus-containing proteins, make up...
About US | ORNL Neutron Sciences
banner What's the Big Deal About Neutron Scattering? Who Conducts Research at SNS and HFIR? Why Do They Come Here? Where Are We? Oak Ridge National Laboratory is home to two of...
Neutron Diffraction @ TOPAZ
Topaz Guide Bender Topaz Guide Bender Neutron Diffraction @ TOPAZ Workshop on Single Crystal Neutron Diffraction picture 2 September 29 - October 1, 2011 * Spallation Neutron Source * Oak Ridge National Laboratory * Oak Ridge TN, USA TOPAZ 2011 Home Contacts Agenda and Important Deadlines Registration and Payment filler Workshop summary and purpose A workshop on single crystal neutron diffraction will be held at the Spallation Neutron Source at the Oak Ridge National Laboratory (ORNL). It will present invited and contributed talks to showcase cutting edge science and examples where neutron diffraction can make significant contributions; and provide training in neutron structure analysis and sample screening for the preparation of instrument beam-time proposals. TOPAZ is a high resolution wavelength-resolved Laue diffractometer with a versatile sample environment. Commissioning user experiments have demonstrated successfully the instrument capability for structural study of a vitamin B12 derivative, ion distribution in Li-ion battery materials, order and disorder in shape memory intermetallics, magnetic phase transition in multiferroic single crystal and functional thin films. The workshop is directed towards experienced neutron diffraction users and new users alike and encourages members to highlight their research and interest in structure analysis and investigation. The workshop will give opportunity to bring your own single crystal and screen sample quality and scattering power on TOPAZ @ room temperature, to evaluate data collection time and quality for an anticipated experiment. Finally, an opportunity to compose a proposal for neutron beam time (http://neutrons.ornl.gov/users/proposals.shtml) with staff will be provided in the framework of the workshop. The workshop format is well suited for researchers to contribute by showcasing their research and bring their research group or graduate student, who would like to test a single crystal sample. User access training for the ORNL neutron scattering facility will be included. It will be valid for future experiments.
RIJKSUNIVERSITEIT GRONINGEN In-situ element analysis from gamma-ray and neutron spectra using a
experimentally. Figure 2.1: Schematic presentation of the neutron elastic scattering process (CANDU04). #12 process (CANDU04). Instead of re-emitting a neutron as in inelastic scattering, the compound nucleus may
Groningen, Rijksuniversiteit
San Eusebio Image #1
SES-1: General overview of the San Eusebio tropical montane forest study area, Venezuela. (Photograph taken 1973-74 by Dr. H.W. Fassbender, Fachhochschule HildesheimHolzminden,...
Light and Color in Nature -Scattering Effects -
in reactor, nuclear bomb · Limit: Diffusion Theory Very many scattering events Effective anisotropy · Strongly wavelength-dependent (1/4) WS03/04: Light and Color in Nature Scattering Scattering Theory equation · Astrophysics Radiation density inside stars · Nuclear physics Neutron density & velocity
Assarsson, Ulf
San Francisco Biodiesel | Open Energy Information
Open Energy Info (EERE)
San Francisco Biodiesel Place San Francisco, California Zip 94103 Product Biodiesel producer based in California. The company is a community coop References San Francisco...
Single-crystal neutron diffraction measures the elastic Bragg reflection intensities from crystals of a material, the structure of which is the subject of investigation. A single crystal is placed in a beam of neutrons produced at a nuclear reactor or at a proton accelerator-based spallation source. Single-crystal diffraction measurements are commonly made at thermal neutron beam energies, which correspond to neutron wavelengths in the neighborhood of 1 Angstrom. For high-resolution studies requiring shorter wavelengths (ca. 0.3-0.8 Angstroms), a pulsed spallation source or a high-temperature moderator (a ''hot source'') at a reactor may be used. When complex structures with large unit-cell repeats are under investigation, as is the case in structural biology, a cryogenic-temperature moderator (a ''cold source'') may be employed to obtain longer neutron wavelengths (ca. 4-10 Angstroms). A single-crystal neutron diffraction analysis will determine the crystal structure of the material, typically including its unit cell and space group, the positions of the atomic nuclei and their mean-square displacements, and relevant site occupancies. Because the neutron possesses a magnetic moment, the magnetic structure of the material can be determined as well, from the magnetic contribution to the Bragg intensities. This latter aspect falls beyond the scope of the present unit; for information on magnetic scattering of neutrons see Unit 14.3. Instruments for single-crystal diffraction (single-crystal diffractometers or SCDs) are generally available at the major neutron scattering center facilities. Beam time on many of these instruments is available through a proposal mechanism. A listing of neutron SCD instruments and their corresponding facility contacts is included in an appendix accompanying this unit.
Former User Group Chair Enthusiastic About Relevance of Neutron Scattering Former User Group Chair Enthusiastic About Relevance of Neutron Scattering to Industrial Research Former User Group Chair Mike Crawford Mike Crawford, DuPont Research and Development. The drive is intensifying to encourage research partnerships between Neutron Sciences and private industry. Such partnerships, a long-term strategic goal set by the DOE's Basic Energy Sciences Advisory Committee, will deliver industry and its technological problems to SNS and HFIR, where joint laboratory-industry teams can use the unparalleled resources available here to resolve them. "SNS is a tremendous facility. It has the potential to have a couple of thousand user visits a year and, if they build another target station in the future, you're probably talking about 4000 user visits a year,"
Spallation Neutron Source The Spallation Neutron Source (SNS)
F/gim F/gim Spallation Neutron Source The Spallation Neutron Source (SNS) gives researchers more detailed informa- tion on the structure and dynamics of physical and biological materials than ever before possible. This accelerator- based facility provides the most intense pulsed neutron beams in the world. Scien- tists are able to count scattered neutrons, measure their energies and the angles at which they scatter, and map their final positions. SNS enables measurements of greater sensitivity, higher speed, higher resolution, and in more complex sample environments than have been possible at existing neutron facilities. Future Growth SNS was designed from the outset to accommodate a second target station, effectively doubling the capacity of the
SANS Publications - 2008
... 52, Neutron transmission of single-crystal magnesium fluoride, JG Barker, DF Mildner, JA Rodriguez, P. Thiyagarajan, J Appl. Cryst. 41, 6, 1003, 2008 ...
Glossary Term - Neutron Emission
Neutron Previous Term (Neutron) Glossary Main Index Next Term (Niobe) Niobe Neutron Emission After neutron emission, an atom contains one less neutron. Neutron emission is one...
DIFFERENTIAL NEUTRON THERMALIZATION. Annual Summary Report, October 1, 1961 through September 30, 1962
Experimental and theoretical work on the interaction mechanisms by which neutrons exchange energy with H atoms involves treating neutron thermalization as neutron interactions with energy levels in the atoms. Cold moderators are presently being studied in order to optimize the source of cold neutrons. Cold neutrons are provided from an accelerator arrangement that directs electrons against a Fansteel target producing fast neutrons. Thermal neutrons, produced by moderation of fast neutrons, are passed through a chopper. Several moderators are evaluated, and neutron emission time measurements by crystal diffraction and beam chopper techniques point out emission time dependence on thickness, moderator, and temperature. The neutron beam chopper used presently is described, and results of neutron scattering by liquid para- and orthohydrogen are displayed and compared with theoretical predictions made with a perfect hydrogen gas model. Inelastic scattering of neutrons by liquid H is discussed, and theoretical and experimental results of inelastic scattering by polyethylene are also included. (D.C.W.)
Whittemore, W L
Neutron Radiography
Table 8 Characteristics of neutron radiography at various neutron-energy ranges...Good discrimination between materials and ready availability
Neutron Sources
Table 1 Characteristics of neutron radiography at various neutron-energy ranges...Good discrimination between materials, and ready
San Francisco Operations Office
Office of Legacy Management (LM)
San Francisco Operations Office San Francisco Operations Office 1333 Broadway Oakland, California 94612 Dr. Joseph 0. Ward, Chief Radiological Health Section Department of Health Services 744 P Street Sacramento, California, 95814 SUBJECT: Certification Docket of Gilman Hall Dear Dr. Ward: The Department of Energy (DOE) has completed and reviewed the remedial ac- tions of Gilman Hall located at the University of California, Berkeley, California. Based on this review, DOE certifies that the condition of Gilman Hall is radiologically acceptable for restricted use under the con- trols of the University of California's State General License 1333-62 pro- vided that the University's Office of Environmental Health and Safety con- tinues to survey Gilman Hall and monitor whenever remodeling or renovation
Portable Neutron Sensors for Emergency Response Operations
This article presents the experimental work performed in the area of neutron detector development at the Remote Sensing Laboratory�Andrews Operations (RSL-AO) sponsored by the U.S. Department of Energy, National Nuclear Security Administration (NNSA) in the last four years. During the 1950s neutron detectors were developed mostly to characterize nuclear reactors where the neutron flux is high. Due to the indirect nature of neutron detection via interaction with other particles, neutron counting and neutron energy measurements have never been as precise as gamma-ray counting measurements and gamma-ray spectroscopy. This indirect nature is intrinsic to all neutron measurement endeavors (except perhaps for neutron spin-related experiments, viz. neutron spin-echo measurements where one obtains ?eV energy resolution). In emergency response situations generally the count rates are low, and neutrons may be scattered around in inhomogeneous intervening materials. It is also true that neutron sensors are most efficient for the lowest energy neutrons, so it is not as easy to detect and count energetic neutrons. Most of the emergency response neutron detectors are offshoots of nuclear device diagnostics tools and special nuclear materials characterization equipment, because that is what is available commercially. These instruments mostly are laboratory equipment, and not field-deployable gear suited for mobile teams. Our goal is to design and prototype field-deployable, ruggedized, lightweight, efficient neutron detectors.
Awards 2007 | ORNL Neutron Sciences
7 7 Staff Awards: 2007 Chakoumakos elected MSA Fellow Bryan Chakoumakos Neutron scientist Bryan Chakoumakos was recently elected a fellow of the Mineralogical Society of America. A member of the Neutron Scattering Science Division, Bryan leads the Single-Crystal Diffraction Group. The group has five neutron scattering instruments in various stages of design and construction, located at HFIR and SNS. The MSA was founded in 1919 and, among other goals, encourages fundamental research on natural materials and supports education through its publications, educational grants, and courses. Pharos Neutron Detector System Researchers at the Department of Energy's Oak Ridge National Laboratory have won six R&D 100 Awards, given annually by R&D Magazine to the year's
Local structures of polar wurtzites Zn1-xMgxO studied by raman and 67Zn/25Mg NMR spectroscopies and by total neutron scattering
Research in the area of polar semiconductor heterostructures has been growing rapidly, driven in large part by interest in two-dimensional electron gas (2DEG) systems. 2DEGs are known to form at heterojunction interfaces that bear polarization gradients. They can display extremely high electron mobilities, especially at low temperatures, owing to spatial confinement of carrier motions. Recent reports of 2DEG behaviors in Ga{sub 1-x}Al{sub x}N/GaN and Zn{sub 1-x}Mg{sub x}O/ZnO heterostructures have great significance for the development of quantum Hall devices and novel high-electron-mobility transistors (HEMTs). 2DEG structures are usually designed by interfacing a polar semiconductor with its less or more polar alloys in an epitaxial manner. Since the quality of the 2DEG depends critically on interface perfection, as well as the polarization gradient at the heterojunction, understanding compositional and structural details of the parent and alloy semiconductors is an important component in 2DEG design and fabrication. Zn{sub 1-x}Mg{sub x}O/ZnO is one of the most promising heterostructure types for studies of 2DEGs, due to the large polarization of ZnO, the relatively small lattice mismatch, and the large conduction band offsets in the Zn{sub 1-x}Mg{sub x}O/ZnO heterointerface. Although 2DEG formation in Zn{sub 1-x}Mg{sub x}O/ZnO heterostructures have been researched for some time, a clear understanding of the alloy structure of Zn{sub 1-x}Mg{sub x}O is currently lacking. Here, we conduct a detailed and more precise study of the local structure of Zn{sub 1-x}Mg{sub x}O alloys using Raman and solid-state nuclear magnetic resonance (NMR), in conjunction with neutron diffraction techniques.
Proffen, Thomas E [Los Alamos National Laboratory; Kim, Yiung- Il [UCSB; Cadars, Sylvian [UCSB; Shayib, Ramzy [UCSB; Feigerle, Charles S [UNIV OF TENNESSEE; Chmelka, Bradley F [UCSB; Seshadri, Ram [UCSB
Videos & Tutorials - Science | ORNL Neutron Sciences
and 2010 National School on Neutron & X-Ray Scattering. This annual school is hosted by ORNL and Argonne National Laboratory. Some of this material is protected by copyright....
Low energy neutron-proton interactions
There have been few measurements of cross sections for neutron-proton scattering and radiative capture below 1 MeV. Those measurements which do exist are at a small number of energies and are often inconsistent with ...
Daub, Brian (Brian Hollenberg)
Data Analysis & Visualization Division | Neutron Science | ORNL
Breast Tissue Imaging | ORNL Neutron Sciences
Neutron scattering measures samples too hot to hold Neutron scattering measures samples too hot to hold Research Contact: Kenneth Kelton August 2013 Liquids and glasses can have unique optical, electronic, and structural applications but are poorly understood compared to crystalline materials, limiting the ability to take advantage of the characteristics of glasses in a range of applications. Containers can react with molten samples at high temperatures or can favor the growth of crystals over the formation of glasses. Using the chemical and isotopic sensitivity of neutron scattering to understand these disordered structures requires a new capability to hold samples in a neutron beam at high temperature without using a solid physical container. New sample environment equipment at Oak Ridge National Laboratory's (ORNL) Spallation Neutron Source (SNS) enables scientists to
Better Buildings Partners: San Diego
GreenBuild Conference in San Francisco to the Sacramento Municipal Utility District's homeowner workshop, the roadshow staff engaged thousands of Californians in a quest to make...
Better Buildings Partners: San Jose
Residential Energy Efficiency Solutions Conference Since May 2011, Better Buildings Program San Jose (BBPSJ) and its community partners have offered affordable energy...
Glossary Term - Neutron
Neutrino Previous Term (Neutrino) Glossary Main Index Next Term (Neutron Emission) Neutron Emission Neutron A Neutron Neutrons are uncharged particles found within atomic nuclei....
About Neutrons
Neutron Basics Neutron Basics A neutron is one of the fundamental particles that make up matter. This uncharged particle exists in the nucleus of a typical atom, along with its positively charged counterpart, the proton. Protons and neutrons each have about the same mass, and both can exist as free particles away from the nucleus. In the universe, neutrons are abundant, making up more than half of all visible matter. Find Out What a Neutron Is Youtube icon Properties of Neutrons How Can Neutrons Be Used for Research? Image of glucose movement in plants Neutron imaging techniques have been able to determine the precise movement of glucose in plants. This knowledge can help scientists better understand how biomass can be efficiently converted into fuel. Neutrons have many properties that make them ideal for certain types of
Biology & Medicine Archive Biology & Medicine Archive Research Highlights Biology & Medicine Archive Small-Angle Neutron Scattering Team Finds Structural Differences in Sindbis Virus Particles from Different Host Species (2010) Published Work: "The Structure of Sindbis Virus Produced from Vertebrate and Invertebrate Hosts as Determined by Small-Angle Neutron Scattering" Contact: Flora Meilleur Targeted Drug Delivery Systems Studies of the unique structure of synthetic molecules will help in the development of drugs that can target diseased areas of the body. This researched on dendrimers revealed how molecules function within solutions at different pH levels. (2008) Research in progress. Contact: Wei-Ren Chen "Intelligent" Polymers for Biomedical Technologies
Porosity of coal and shale: Insights from gas adsorption and SANS/USANS techniques
Two Pennsylvanian coal samples (Spr326 and Spr879-IN1) and two Upper Devonian-Mississippian shale samples (MM1 and MM3) from the Illinois Basin were studied with regard to their porosity and pore accessibility. Shale samples are early mature stage as indicated by vitrinite reflectance (R{sub o}) values of 0.55% for MM1 and 0.62% for MM3. The coal samples studied are of comparable maturity to the shale samples, having vitrinite reflectance of 0.52% (Spr326) and 0.62% (Spr879-IN1). Gas (N{sub 2} and CO{sub 2}) adsorption and small-angle and ultrasmall-angle neutron scattering techniques (SANS/USANS) were used to understand differences in the porosity characteristics of the samples. The results demonstrate that there is a major difference in mesopore (2-50 nm) size distribution between the coal and shale samples, while there was a close similarity in micropore (coal is pore-size specific and can vary significantly between coal samples; also, higher accessibility corresponds to higher adsorption capacity. Accessibility of pores in shale samples is low.
Mastalerz, Maria [Indiana Geological Survey; He, Lilin [ORNL; Melnichenko, Yuri B [ORNL; Rupp, John A [ORNL
ABAREX: A neutron spherical optical-statistical model code
The spherical optical-statistical model is briefly reviewed and the capabilities of the neutron scattering code, ABAREX, are presented. Input files for ten examples, in which neutrons are scattered by various nuclei, are given and the output of each run is discussed in detail.
Lawson, R.D.
Neutron beam imaging at neutron spectrometers at Dhruva
A low efficiency, 2-Dimensional Position Sensitive Neutron Detector based on delay line position encoding is developed. It is designed to handle beam flux of 10{sup 6}-10{sup 7} n/cm{sup 2}/s and for monitoring intensity profiles of neutron beams. The present detector can be mounted in transmission mode, as the hardware allows maximum neutron transmission in sensitive region. Position resolution of 1.2 mm in X and Y directions, is obtained. Online monitoring of beam images and intensity profile of various neutron scattering spectrometers at Dhruva are presented. It shows better dynamic range of intensity over commercial neutron camera and is also time effective over the traditionally used photographic method.
Desai, Shraddha S.; Rao, Mala N. [Solid State Physics Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085 (India)
Better Buildings Neighborhood Program: San Antonio, Texas
Antonio, Texas to someone by E-mail Share Better Buildings Neighborhood Program: San Antonio, Texas on Facebook Tweet about Better Buildings Neighborhood Program: San Antonio,...
Research Highlights | Neutron Science | ORNL
Research Highlights Research Highlights Biology & Medicine Biotechnology & Energy Fundamental Physics Imaging Magnetism Materials Nanotechnology Superconductivity Facilities and Capabilities Instruments User Program Publications and Resources Science and Education News and Awards NScD Careers Supporting Organizations Neutron Science Home | Science & Discovery | Neutron Science | Research Highlights SHARE Research Highlights No current Research Highlights found. 1-10 of 43 Results Comprehensive phonon "map" offers direction for engineering new thermoelectric devices January 08, 2014 - To understand how to design better thermoelectric materials, researchers are using neutron scattering at SNS and HFIR to study how a compound known as AgSbTe2, or silver antimony telluride, is
Neutron dosimetry
A method of measuring neutron radiation within a nuclear reactor is provided. A sintered oxide wire is disposed within the reactor and exposed to neutron radiation. The induced radioactivity is measured to provide an indication of the neutron energy and flux within the reactor.
Quinby, Thomas C. (Kingston, TN)
Ultracold Neutron Production in a Pulsed Neutron Beam Line
We present the results of an Ultracold neutron (UCN) production experiment in a pulsed neutron beam line at the Los Alamos Neutron Scattering Center. The experimental apparatus allows for a comprehensive set of measurements of UCN production as a function of target temperature, incident neutron energy, target volume, and applied magnetic field. However, the low counting statistics of the UCN signal expected can be overwhelmed by the large background associated with the scattering of the primary cold neutron flux that is required for UCN production. We have developed a background subtraction technique that takes advantage of the very different time-of-flight profiles between the UCN and the cold neutrons, in the pulsed beam. Using the unique timing structure, we can reliably extract the UCN signal. Solid ortho-D$_2$ is used to calibrate UCN transmission through the apparatus, which is designed primarily for studies of UCN production in solid O$_2$. In addition to setting the overall detection efficiency in the...
Lavelle, C M; Manus, G; McChesney, P M; Salvat, D J; Shin, Y; Makela, M; Morris, C; Saunders, A; Couture, A; Young, A R; Liu, C -Y
We present the results of an Ultracold neutron (UCN) production experiment in a pulsed neutron beam line at the Los Alamos Neutron Scattering Center. The experimental apparatus allows for a comprehensive set of measurements of UCN production as a function of target temperature, incident neutron energy, target volume, and applied magnetic field. However, the low counting statistics of the UCN signal expected can be overwhelmed by the large background associated with the scattering of the primary cold neutron flux that is required for UCN production. We have developed a background subtraction technique that takes advantage of the very different time-of-flight profiles between the UCN and the cold neutrons, in the pulsed beam. Using the unique timing structure, we can reliably extract the UCN signal. Solid ortho-D$_2$ is used to calibrate UCN transmission through the apparatus, which is designed primarily for studies of UCN production in solid O$_2$. In addition to setting the overall detection efficiency in the apparatus, UCN production data using solid D$_2$ suggest that the UCN upscattering cross-section is smaller than previous estimates, indicating the deficiency of the incoherent approximation widely used to estimate inelastic cross-sections in the thermal and cold regimes.
C. M. Lavelle; W. Fox; G. Manus; P. M. McChesney; D. J. Salvat; Y. Shin; M. Makela; C. Morris; A. Saunders; A. Couture; A. R. Young; C. -Y. Liu
Better Buildings Neighborhood Program: San Jose
San Jose to San Jose to someone by E-mail Share Better Buildings Neighborhood Program: San Jose on Facebook Tweet about Better Buildings Neighborhood Program: San Jose on Twitter Bookmark Better Buildings Neighborhood Program: San Jose on Google Bookmark Better Buildings Neighborhood Program: San Jose on Delicious Rank Better Buildings Neighborhood Program: San Jose on Digg Find More places to share Better Buildings Neighborhood Program: San Jose on AddThis.com... Better Buildings Residential Network Progress Stories Interviews Videos Events Quick Links to Partner Information AL | AZ | CA | CO | CT FL | GA | IL | IN | LA ME | MD | MA | MI | MO NE | NV | NH | NJ | NY NC | OH | OR | PA | SC TN | TX | VT | VI | VA WA | WI San Jose, California San Jose Leverages Partnerships to Improve Low-Income Households' Energy
Structure and Dynamics of Cholesterol-Containing Polyunsaturated Lipid Membranes Studied by Neutron Diffraction and NMR
by Neutron Diffraction and NMR Mihaela Mihailescu � Olivierwas carried out by neutron diffraction, 2 H-NMR and 13C-MAS NMR. Scattering length distribution func- tions of
Mihailescu, Mihaela; Soubias, Olivier; Worcester, David; White, Stephen H.; Gawrisch, Klaus
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
Polarized Neutron in Structural Biology Present and Future Outlook
Hydrogen has a strong polarization-dependent neutron scattering cross section. This property has been exploited in the study of soft matters, especially biological macromolecules. When a polarized neutron beam is scattered off a polarized hydrogenous sample, the otherwise large hydrogen incoherent cross section is drastically reduced while the coherent signal is significantly increased. Past experiments have demonstrated the potentials and benefits of polarized neutron scattering from soft materials. The main technical challenge of polarized neutron scattering from biological matters lies at sample polarization. Dynamic nuclear polarization is a proven yet rather sophisticated technique. Its complexity is one of the main reasons for the technique's slow adoption. The future of polarized neutron scattering in biology may rest largely in neutron protein crystallography. Polarization of protein crystals is much easier to accomplish, since protein crystals are typically rather small (<<1 mm) and only require small and easy- to-operate polarization apparatuses. In addition, the high resolution nature of neutron protein crystallography means that we will be able to study individual atoms using the polarized neutron scattering technique.
Zhao, Jinkui [ORNL; Robertson, Lee [ORNL; Herwig, Kenneth W [ORNL; Crabb, Don [University of Virginia
Chapter 199 NEUTRON SCATTERING STUDIES OF ...
... 4) materials. The basic crystal structure is tetragonal I4/mmm (T phase) in which the Cu Page 5. LANTHANIDE MAGNETIC ...
... Fast pyrolysis is one process that can be used to convert woody biomass into fuels and chemicals, however the liquid product created is an ...
Neutron Scattering Investigation of the Structure and ...
... floor, their detrimental formation in gas and oil pipelines, possible existence ... Last modified 07-March-2005 by website owner: NCNR (attn: Yun Liu).
Forum on Inelastic Neutron Scattering (FINS 2011)
sessions are planned for discussions of inelastic instrumentation needs for the SNS and HFIR, sample environment equipment for the inelastic suite, enabling programmatic research...
New States of Matter and their Excitations Joint Meeting 12 - 14 September, 2012 Clinch River Cabin * Oak Ridge, Tennessee, USA About the School Agenda Organizers Venue filler...
Recent Neutron Scattering Results from Geometrically ...
... of Physics, The University of Texas at Austin, Austin, Texas 78712. ... Recently, the quantized energy states under magnetic fields (Landau levels) and ...
Long-Range Neutron Detection
A neutron detector designed for detecting neutron sources at distances of 50 to 100 m has been constructed and tested. This detector has a large surface area (1 m{sup 2}) to enhance detection efficiency, and it contains a collimator and shielding to achieve direction sensitivity and reduce background. An unusual feature of the detector is that it contains no added moderator, such as polyethylene, to moderate fast neutrons before they reach the {sup 3}He detector. As a result, the detector is sensitive mainly to thermal neutrons. The moderator-free design reduces the weight of the detector, making it more portable, and it also aids in achieving directional sensitivity and background reduction. Test results show that moderated fission-neutron sources of strength about 3 x 10{sup 5} n/s can be detected at a distance out to 70 m in a counting time of 1000 s. The best angular resolution of the detector is obtained at distances of 30 m or less. As the separation .distance between the source and detector increases, the contribution of scattered neutrons to the measured signal increases with a resultant decrease in the ability to detect the direction to a distant source. Applications for which the long-range detector appears to be suitable include detecting remote neutron sources (including sources in moving vehicles) and monitoring neutron storage vaults for the intrusion of humans and the effects they make on the detected neutron signal. Also, the detector can be used to measure waste for the presence of transuranic material in the presence of high gamma-ray background. A test with a neutron source (3 x 10{sup 5} n/s) in a vehicle showed that the detector could readily measure an increase in count rate at a distance of 10 m for vehicle speeds up to 35 mph (the highest speed tested). These results. indicate that the source should be detectable at this distance at speeds up to 55 mph.
AJ Peurrung; DC Stromswold; RR Hansen; PL Reeder; DS Barnett
... for Neutron Reaction Rate Measurements, JA Grundl, V. Spiegel, CM Eisenhauer, HT Heaton II, DM Gilliam (NBS), and J. Bigelow (ORNL), Nucl. ...
Weak Interaction Neutron Production Rates in Fully Ionized Plasmas
Employing the weak interaction reaction wherein a heavy electron is captured by a proton to produce a neutron and a neutrino, the neutron production rate for neutral hydrogen gases and for fully ionized plasmas is computed. Using the Coulomb atomic bound state wave functions of a neutral hydrogen gas, our production rate results are in agreement with recent estimates by Maiani {\\it et al}. Using Coulomb scattering state wave functions for the fully ionized plasma, we find a substantially enhanced neutron production rate. The scattering wave function should replace the bound state wave function for estimates of the enhanced neutron production rate on water plasma drenched cathodes of chemical cells.
A. Widom; J. Swain; Y. N. Srivastava
Characterization of deep weathering and nanoporosity development in shale - a neutron study
We used small-angle and ultra-small-angle neutron scattering (SANS/USANS) to characterize the evolution of nanoscale features in weathering Rose Hill shale within the Susquehanna/Shale Hills Observatory (SSHO). The SANS/USANS techniques, here referred to as neutron scattering (NS), characterize porosity comprised of features ranging from approximately 3 nm to several micrometers in dimension. NS was used to investigate shale chips sampled by gas-powered drilling ('saprock') or by hand-augering ('regolith') at ridgetop. At about 20 m depth, dissolution is inferred to have depleted the bedrock of ankerite and all the chips investigated with NS are from above the ankerite dissolution zone. NS documents that 5--6% of the total ankerite-free rock volume is comprised of isolated, intraparticle pores. At 5 m depth, an abrupt increase in porosity and surface area corresponds with onset of feldspar dissolution in the saprock and is attributed mainly to peri-glacial processes from 15 000 years ago. At tens of centimeters below the saprock-regolith interface, the porosity and surface area increase markedly as chlorite and illite begin to dissolve. These clay reactions contribute to the transformation of saprock to regolith. Throughout the regolith, intraparticle pores in chips connect to form larger interparticle pores and scattering changes from a mass fractal at depth to a surface fractal near the land surface. Pore geometry also changes from anisotropic at depth, perhaps related to pencil cleavage created in the rock by previous tectonic activity, to isotropic at the uppermost surface as clays weather. In the most weathered regolith, kaolinite and Fe-oxyhydroxides precipitate, blocking some connected pores. These precipitates, coupled with exposure of more quartz by clay weathering, contribute to the decreased mineral-pore interfacial area in the uppermost samples. These observations are consistent with conversion of bedrock to saprock to regolith at SSHO due to: (1) transport of reactants (e.g., water, O{sub 2}) into primary pores and fractures created by tectonic events and peri-glacial effects; (2) mineral-water reactions and particle loss that increase porosity and the access of water into the rock. From deep to shallow, mineral-water reactions may change from largely transport-limited where porosity was set largely by ancient tectonic activity to kinetic-limited where porosity is changing due to climate-driven processes.
Jin, Lixin [ORNL; Rother, Gernot [ORNL; Cole, David R [ORNL; Mildner, David [ORNL; Duffy, Christopher S [ORNL; Brantley, Susan L [ORNL
... 31, Neutron transmission of single-crystal magnesium fluoride, JG Barker, DF Mildner, JA Rodriguez, P. Thiyagarajan, J Appl. Cryst. 41, 6, 1003, 2008 ...
... 24, Neutron transmission of single-crystal magnesium fluoride, JG Barker, DF Mildner, JA Rodriguez, P. Thiyagarajan, J Appl. Cryst. 41, 6, 1003, 2008 ...
A system for fast neutron radiography
A system has been designed and a neutron generator installed to perform fast neutron radiography. With this sytem, objects as small as a coin or as large as a waste drum can be radiographed. The neutron source is an MF Physics A-711 neutron generator which produces 3x10{sup 10} neutrons/second with an average energy of 14.5 MeV. The radiography system uses x-ray scintillation screens and film in commercially available cassettes. The cassettes have been modified to include a thin sheet of plastic to convert neutrons to protons through elastic scattering from hydrogen and other low Z materials in the plastic. For film densities from 1.8 to 3.0, exposures range from 1.9x10{sup 7} to 3.8x10{sup 8} n/cm{sup 2} depending on the type of screen and film.
Klann, R.T.
Anomalous and resonance small angle scattering
Significant changes in the small angle scattered intensity can be induced by making measurements with radiation close to an absorption edge of an appropriate atomic species contained in the sample. These changes can be related quantitatively to the real and imaginary anomalous dispersion terms for the scattering factor (x-rays) or scattering length (neutrons). The physics inherent in these anomalous dispersion terms is first discussed before considering how they enter the relevant scattering theory. Two major areas of anomalous scattering research have emerged; macromolecules in solution and unmixing of metallic alloys. Research in each area is reviewed, illustrating both the feasibility and potential of these techniques. All the experimental results reported to date have been obtained with x-rays. However, it is pointed out that the formalism is the same or the analogue experiment with neutrons, and a number of suitable isotopes exist which exhibit resonance in an accessible range of energy. Potential applications of resonance small-angle neutron scatterings are discussed. 8 figs.
Epperson, J.E.; Thiyagarajan, P.
Anomalous and resonance small angle scattering: Revision
Significant changes in the small angle scattered intensity can be induced by making measurements with radiation close to an absorption edge of an appropriate atomic species contained in the sample. These changes can be related quantitatively to the real and imaginary anomalous dispersion terms for the scattering factor (x-rays) or scattering length (neutrons). The physics inherent in these anomalous dispersion terms is first discussed before considering how they enter the relevant scattering theory. Two major areas of anomalous scattering research have emerged; macromolecules in solution and unmixing of metallic alloys. Research in each area is reviewed, illustrating both the feasibility and potential of these techniques. All the experimental results reported to date have been obtained with x-rays. However, it is pointed out that the formalism is the same for the analogue experiment with neutrons, and a number of suitable isotopes exist which exhibit resonance in an accessible range of energy. Potential applications of resonance small angle neutron scatterings are discussed. 54 refs., 8 figs., 1 tab.
Solar America City - San Diego, California
This fact sheet highlights San Diego, California, as a DOE Solar America City. Through various collaborations at the local level, San Diego has a goal of 50 megawatts of solar installed by 2010.
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Better Buildings Neighborhood Program: San Diego
Diego to Diego to someone by E-mail Share Better Buildings Neighborhood Program: San Diego on Facebook Tweet about Better Buildings Neighborhood Program: San Diego on Twitter Bookmark Better Buildings Neighborhood Program: San Diego on Google Bookmark Better Buildings Neighborhood Program: San Diego on Delicious Rank Better Buildings Neighborhood Program: San Diego on Digg Find More places to share Better Buildings Neighborhood Program: San Diego on AddThis.com... Better Buildings Residential Network Progress Stories Interviews Videos Events Quick Links to Partner Information AL | AZ | CA | CO | CT FL | GA | IL | IN | LA ME | MD | MA | MI | MO NE | NV | NH | NJ | NY NC | OH | OR | PA | SC TN | TX | VT | VI | VA WA | WI San Diego County, California Energy Upgrade California Motivates Home Improvements in San Diego County
Superconductivity Superconductivity Research Highlights Superconductivity Archive New Neutron Studies Support Magnetism's Role in Superconductors Recent neutron scattering experiments give strong evidence that if superconductivity is related to a material's magnetic properties, the same mechanisms are behind both copper-based, high-temperature superconductors and the newly discovered iron-based superconductors. The research was performed at SNS and HFIR and the ISIS Facility at Rutherford Appleton Laboratory in England. (2010) Published Work: "Evolution of spin excitations into the superconducting state in FeTe1-xSex" Contact: Mark Lumsden Advances in Unconventional Iron-Based Superconductors The discovery of more diverse superconducting materials will lead to more
Magnetism Highlights| Neutron Science | ORNL
Magnetism Magnetism SHARE Magnetism Highlights 1-5 of 5 Results ARCS maps collaborative magnetic spin behavior in iron telluride December 01, 2011 - Researchers have long thought that magnetism and superconductivity are mutually exclusive. The former typically involves localized atomic electrons. The latter requires freely propagating, itinerant electrons. Unexpected Magnetic Excitations in Doped Insulator Surprise Researchers October 01, 2011 - When doping a disordered magnetic insulator material with atoms of a nonmagnetic material, the conventional wisdom is that the magnetic interactions between the magnetic ions in the material will be weakened. Neutron Analysis Reveals Unique Atomic-Scale Behavior of "Cobalt Blue" September 01, 2011 - Neutron scattering studies of "cobalt blue," a
Neutronic reactor
A safety rod for a nuclear reactor has an inner end portion having a gamma absorption coefficient and neutron capture cross section approximately equal to those of the adjacent shield, a central portion containing materials of high neutron capture cross section and an outer end portion having a gamma absorption coefficient at least equal to that of the adjacent shield.
Wende, Charles W. J. (West Chester, PA)
Energy San Francisco Operations Office
Depariment of ' Depariment of ' Energy San Francisco Operations Office 1333 Broadway Oakland, California 94612 FEB 6 1984 Mr. c:c. canners Energy Systems Group Rockwell International Corporation Post Office BOX 309 Canoga Park Dear 8 a CA 91304 G ers : Remedial action was taken to decontaminate the Hot Cave (Building 003) and Sodium Reactor Experiment (SRE) under Contract No. DE-AT03-76SF75008. The report of the post remedial survey, performed by Argonne National Laboratory, indicates that the levels of contamination are below the decontamination criteria agreed to between the State of California and DOE/SAN. Based on- this report and the enclosed letter from J. E. Baublitz to Dr. Wynveen, DOE/SAN is releasing for unrestricted use Building 003 and the SRE. Sincerely,
Neutron source
A neutron source which is particularly useful for neutron radiography consists of a vessel containing a moderating media of relatively low moderating ratio, a flux trap including a moderating media of relatively high moderating ratio at the center of the vessel, a shell of depleted uranium dioxide surrounding the moderating media of relatively high moderating ratio, a plurality of guide tubes each containing a movable source of neutrons surrounding the flux trap, a neutron shield surrounding one part of each guide tube, and at least one collimator extending from the flux trap to the exterior of the neutron source. The shell of depleted uranium dioxide has a window provided with depleted uranium dioxide shutters for each collimator. Reflectors are provided above and below the flux trap and on the guide tubes away from the flux trap.
Cason, J.L. Jr.; Shaw, C.B.
San Diego County - Wind Regulations (California) | Department...
Wind Regulations (California) San Diego County - Wind Regulations (California) < Back Eligibility Commercial Industrial Residential Savings Category Wind Buying & Making...
Images of the EQ-SANS Instrument | ORNL Neutron Sciences
sample environment. Cover Vessel Insert. Cover vessel insert. Detector Module. Detector module. Shutter. Shutter. Bulk Shield insert. Bulk shield insert. 8 mm tube. 8 mm tube...
SANS scientist at the NIST Center for Neutron Research
... Initial appointment is for up to four years. Salary is in the range from $70,000 to $80,000 depending on qualifications and experience. ...
Neutron Sciences at Oak Ridge National Laboratory
Research Research Find out how neutron scattering can benefit your research. Call for Proposals Proposals for beam time at HFIR and SNS will be accepted via the web-based proposal system until 11:59 a.m. EST, (NOON) Wednesday, February 26, 2014. Comprehensive phonon "map" offers direction for engineering new thermoelectric devices. Comprehensive phonon "map" offers direction for engineering new thermoelectric devices. High-pressure studies of rare earth material could lead to lighter, cheaper magnets High-pressure studies of rare earth material could lead to lighter, cheaper magnets Unfrozen mystery: H2O reveals a new secret Unfrozen mystery: H2O reveals a new secret Neutron scattering workshop promotes high-pressure research Neutron scattering workshop promotes high-pressure research.
Chemical and Engineering Materials | Neutron Science | ORNL
Chemical and Engineering Materials Chemical and Engineering Materials SHARE Chemical and Engineering Materials Neutron-based research at SNS and HFIR in Chemical and Engineering Materials strives to understand the structure and dynamics of chemical systems and novel engineering materials. The user community takes advantage of capabilities of neutron scattering for measurements over wide ranges of experimental and operating conditions, including studies of chemical and physical changes in situ. User experiments with diffraction, small-angle scattering, inelastic and quasi-elastic scattering, and neutron imaging instruments address a range of problems in chemistry and in engineering materials research. Current areas of research supported within Chemical and Engineering Materials include: The structure and dynamics of electrical energy storage materials
SOUTHWEST RESEARCH INSTITUTE San Antonio, Texas
SOUTHWEST RESEARCH INSTITUTE San Antonio, Texas July 2010 ii #12;SOUTHWEST RESEARCH INSTITUTE San Antonio, Texas July 2010 iii Abstracts of Test Procedures FUELS FUEL ADDITIVES & FUEL ECONOMY Performed by The Office of Automotive Engineering Southwest Research Institute® San Antonio, Texas July 2010 #12;SOUTHWEST
Chapman, Clark R.
Charged-particle tracking for neutron-deuteron breakup
Particle tracking software has been developed to measure the energy of protons scattered in the breakup process d(n, np)n. The nd breakup experiment is performed at the Weapons Neutron Research facilities at Los Alamos ...
Boddy, Kimberly K
Capabilities of the CNCS Instrument | ORNL Neutron Sciences
in one day. A recent example is a study of the phonon spectra in PbTe, one of the leading thermoelectric materials. Using a combination of inelastic neutron scattering measurements...
Fast Proton Hopping in Ice Fast Proton Hopping in Ice Fast Proton Hopping in Ice (Ih) Confirmed by Quasi-Elastic Neutron Scattering "With these results, we have an experimental proof of fast proton hopping in ice," researcher says Research Contact: Alexander Kolesnikov June 2011, Written by Agatha Bardoel Protons (positive hydrogen ions) in an ice lattice have been "seen" to fast hop from one water molecule to another, using quasi-elastic neutron scattering at the SNS Backscattering Spectrometer, BASIS. This fundamental phenomenon that occurs at very low temperatures has important consequences for future investigations of proton conductivity in solids. The research could open the door to a new understanding of how electrolytes work in a system. Proton hopping in ice occurs when "extra" protons diffuse through
Battery Studies Battery Studies A Wealth of New Battery Research at SNS and HFIR Technical Contacts: Xun-Li Wang, Ashfia Huq, Jung-Hyun Kim October 2010, Written by Carolyn Krause Neutron scattering, capable of looking deep inside the structures of materials used in technologies such as batteries and fuel cells, is a natural tool for research in energy storage and production. Several users of neutron scattering instruments at the SNS and HFIR presented details of their energy-related research to prospective scientific facility users attending the opening session of ORNL's User Week at SNS. Most of the energy-related research reported in the session dealt with batteries for electric and hybrid electric cars. Better batteries are also needed for storing excess electricity generated by wind and solar power so
Alternatives to 3He for Neutron Detection for Homeland Security
Neutron detection is an essential aspect of interdiction of radiological threats for national security purposes, since plutonium, a material used for nuclear weapons, is a significant source of fission neutrons. Radiation portal monitoring systems, of which there are thousands deployed for homeland security and non-proliferation purposes, currently use 3He gas-filled proportional counters for detecting neutrons. Because of the high usage of 3He for neutron scattering science and national security, the supply has dwindled, and can no longer meet the demand. Consequently, a replacement technology for neutron detection is required in the very near future.
Kouzes, Richard T.; Conlin, Kenneth E.; Ely, James H.; Erikson, Luke E.; Kernan, Warnick J.; Lintereur, Azaree T.; Siciliano, Edward R.; Stephens, Daniel L.; Stromswold, David C.; Van Ginhoven, Renee M.; Woodring, Mitchell L.
Thermal neutron detection system
According to the present invention, a system for measuring a thermal neutron emission from a neutron source, has a reflector/moderator proximate the neutron source that reflects and moderates neutrons from the neutron source. The reflector/moderator further directs thermal neutrons toward an unmoderated thermal neutron detector.
Peurrung, Anthony J. (Richland, WA); Stromswold, David C. (West Richland, WA)
A nuclear reactor is described wherein horizontal rods of thermal- neutron-fissionable material are disposed in a body of heavy water and extend through and are supported by spaced parallel walls of graphite.
Scattering Functions of Yolk-Shell Particles
The single-particle small-angle scattering properties of the yolk-shell particle, a new type of core-shell particle with a mobile core within the hosting shell, are systematically investigated. The Debye spatial autocorrelation function, pair distance distribution function and intraparticle structure factor (form factor) are calculated and compared to the corresponding scattering functions of reference systems of hard sphere and concentric core-shell particles with identical sizes. Based on our theoretical calculations, we find that the broken centrosymmetry, originating from the mobility of the trapped yolk, results in an imaginary scattering amplitude. As a result, it contributes an additional destructive interference term which smears certain features present in the scattering functions of the reference systems. Based on our theoretical models, we present the prospect of jointly using small angle neutron and x-ray scattering techniques to quantitatively determine the structural characteristics of yolk-shell particles.
Li, Xin [ORNL] [ORNL; Liu, Kao-Hsiang [National Taiwan University] [National Taiwan University; Wu, Bin [ORNL] [ORNL; Sanchez-Diaz, Luis E [ORNL] [ORNL; Smith, Gregory Scott [ORNL] [ORNL; Chen, Wei-Ren [ORNL] [ORNL
HFIR History - ORNL Neutron Sciences
Home › Facilities › HFIR › History Home › Facilities › HFIR › History History of HFIR HFIR was constructed in the mid-1960s to fulfill a need for the production of transuranic isotopes (i.e., "heavy" elements such as plutonium and curium). Since then its mission has grown to include materials irradiation, neutron activation, and, most recently, neutron scattering. In 2007, HFIR completed the most dramatic transformation in its 40-year history. During a shutdown of more than a year, the facility was refurbished and a number of new instruments were installed, as well as a cold neutron source. The reactor was restarted in mid-May; it attained its full power of 85 MW within a couple of days, and experiments resumed within a week. Improvements and upgrades to HFIR include an overhaul of the
Atomic-Scale Behavior of "Cobalt Blue" Atomic-Scale Behavior of "Cobalt Blue" Neutron Analysis Reveals Unique Atomic-Scale Behavior of "Cobalt Blue" Research Contact: Gregory MacDougall ORNL News Release, September 2011, Media Contact: Bill Cabage Cobalt aluminate Just as cobalt blue's lustrous hue attracts artists and decorators, the antiferromagnetic properties of the responsible compound-cobalt aluminate-are attracting neutron scientists at DOE's Oak Ridge National Laboratory. Studies of magnetic interactions deep within the material's atomic structure may provide clues toward the development of energy-efficient technologies. (Light sconce image courtesy of B. Jefferson Bolender. Click image for high res version.) Neutron scattering studies of "cobalt blue," a compound prized by artists
Neutron range spectrometer
A neutron range spectrometer and method for determining the neutron energy spectrum of a neutron emitting source are disclosed. Neutrons from the source are colliminated along a collimation axis and a position sensitive neutron counter is disposed in the path of the collimated neutron beam. The counter determines positions along the collimation axis of interactions between the neutrons in the neutron beam and a neutron-absorbing material in the counter. From the interaction positions, a computer analyzes the data and determines the neutron energy spectrum of the neutron beam. The counter is preferably shielded and a suitable neutron-absorbing material is He-3. 1 fig.
Manglos, S.H.
A neutronic reactor in which neutron moderation is achieved primarily in its reflector is described. The reactor structure consists of a cylindrical central "island" of moderator and a spherical moderating reflector spaced therefrom, thereby providing an annular space. An essentially unmoderated liquid fuel is continuously passed through the annular space and undergoes fission while contained therein. The reactor, because of its small size, is particularly adapted for propulsion uses, including the propulsion of aircraft. (AEC)
Fraas, A.P.; Mills, C.B.
A neutron source is obtained without employing any separate beryllia receptacle, as was formerly required. The new method is safer and faster, and affords a source with both improved yield and symmetry of neutron emission. A Be container is used to hold and react with Pu. This container has a thin isolating layer that does not obstruct the desired Pu--Be reaction and obviates procedures previously employed to disassemble and remove a beryllia receptacle. (AEC)
Richmond, J.L.; Wells, C.E.
Directional neutron detectors for use with 14 MeV neutrons :fiber scintillation methods for directional neutron detection.
Current Joint Test Assembly (JTA) neutron monitors rely on knock-on proton type detectors that are susceptible to X-rays and low energy gamma rays. We investigated two novel plastic scintillating fiber directional neutron detector prototypes. One prototype used a fiber selected such that the fiber width was less than 2.1mm which is the range of a proton in plastic. The difference in the distribution of recoil proton energy deposited in the fiber was used to determine the incident neutron direction. The second prototype measured both the recoil proton energy and direction. The neutron direction was determined from the kinematics of single neutron-proton scatters. This report describes the development and performance of these detectors.
Sunnarborg, Duane A.; Peel, Justin D.; Mascarenhas, Nicholas; Mengesha, Wondwosen
Neutron Instruments Added at Oak Ridge
The neutron scattering facilities at Oak Ridge National Laboratory continue their development as new instruments are commissioned and join the user program at the Spallation Neutron Source and High Flux Isotope Reactor. More than 640 proposals were received for beam time during the January-May 2011 period on SNS and HFIR instruments with about half either being accepted or identified as alternates. The proposal call for the period June-December 2011, announced at http://neutrons.ornl.gov, will close February 23, 2011.
Sample Environment Equipment Categories - ORNL Neutron Sciences
Home › Instruments › Sample Environment Home › Instruments › Sample Environment Sample Environment: Categories of Equipment All Ancillary Equipment Auto Changer Closed Cycle Refrigerators Closed Cycle Refrigerators - Bottom Loading Closed Cycle Refrigerators - Top Loading Furnaces Gas Handling Gas Panel High Pressure Systems Liquid Helium Cryostats Magnet Systems Other Special Environments Sample Cell Sample Stick Ultra Low Temperature Devices Sample Environment: by Beam Line All BL-11A-POWGEN BL-11B-MANDI BL-12-TOPAZ BL-13-Fundamental Neutron Physics Beam Line BL-14A-BL-14A BL-14B-HYSPEC BL-15-Neutron Spin Echo (NSE) BL-16B-VISION BL-17-SEQUOIA BL-18-ARCS BL-1A-TOF-USANS BL-1B-NOMAD BL-2-BASIS BL-3-SNAP BL-4A-Magnetism Reflectometer BL-4B-Liquids Reflectometer BL-5-Cold Neutron Chopper Spectrometer (CNCS) BL-6-EQ-SANS
Science Opportunities at ORNL's Neutron Sources
The Neutron Sciences Directorate at Oak Ridge National Laboratory (ORNL) operates two of the world's most advanced neutron scattering research facilities: the Spallation Neutron Source (SNS) and the High Flux Isotope Reactor (HFIR). Our vision is to provide unprecedented capabilities for understanding structure and properties across the spectrum of biology, chemistry, physics, and engineering, and to stay at the leading edge of neutron science by developing new instruments, tools, and services. This talk will provide an update on the operations of the two research facilities and highlight the significant research that is emerging. For example, scientists from ORNL are at the forefront of research on a new class of iron-based superconductors based on experiments performed at the Triple-Axis Spectrometer at HFIR and ARCS at SNS. The complementary nature of neutron and x-ray techniques will be discussed to spark discussion among attendees.
Anderson, Ian [ORNL, SNS
The New Munich Neutron Source FRM II: Overview and Uses for Biological Studies
Neutron Physics at NIST M. Arif 8th UCN Workshop St. Petersburg Moscow, Russia June 11-21, 2011 #12;NCNR Guide Hall 20 MW Reactor #12;Neutron Physics at the NCNR Beam Flux n cm-2 s-1 Peak Wavelength Facility Low Scatter Neutron Dosimeter Calibration Facility #12;December 31, 2012 Physics Physics Physics
Doster, Wolfgang
Tables are presented of experimental differential neutron cross sections for the elastic scattering of neutrons by nuclei in the energy range of 0 to 15 Mev. Nuclear reactions induced by neutrons are also included, particularly those that are significant for reactor-type calculations. The tables include nuclei from H to Pu. (D.L.C.)
Howerton, R.J.
Neutron Repulsion
Earth is connected gravitationally, magnetically and electrically to its heat source - a neutron star that is obscured from view by waste products in the photosphere. Neutron repulsion is like the hot filament in an incandescent light bulb. Excited neutrons are emitted from the solar core and decay into hydrogen that glows in the photosphere like a frosted light bulb. Neutron repulsion was recognized in nuclear rest mass data in 2000 as the overlooked source of energy, the keystone of an arch that locked together these puzzling space-age observations: 1.) Excess 136Xe accompanied primordial helium in the stellar debris that formed the solar system (Fig. 1); 2.) The Sun formed on the supernova core (Fig. 2); 3.) Waste products from the core pass through an iron-rich mantle, selectively carrying lighter elements and lighter isotopes of each element into the photosphere (Figs. 3-4); and 4.) Neutron repulsion powers the Sun and sustains life (Figs. 5-7). Together these findings offer a framework for understanding how: a.) The Sun generates and releases neutrinos, energy and solar-wind hydrogen and helium; b.) An inhabitable planet formed and life evolved around an ordinary-looking star; c.) Continuous climate change - induced by cyclic changes in gravitational interactions of the Sun's energetic core with planets - has favored survival by adaptation.
Oliver K. Manuel
Californium Neutron Irradiation Facility
Californium Neutron Irradiation Facility. Summary: ... Cf irradiation facility (Photograph by: Neutron Physics Group). Lead Organizational Unit: pml. Staff: ...
EIS-0496: San Luis Transmission Project, Alameda, Merced, San Joaquin and
96: San Luis Transmission Project, Alameda, Merced, San 96: San Luis Transmission Project, Alameda, Merced, San Joaquin and Stanislaus Counties, California EIS-0496: San Luis Transmission Project, Alameda, Merced, San Joaquin and Stanislaus Counties, California Summary DOE's Western Area Power Administration, with the Bureau of Reclamation as a cooperating agency, is preparing a joint EIS and environmental impact report (under the California Environmental Quality Act) to evaluate the potential environmental impacts of the proposed interconnection of certain San Luis Unit facilities to Western's Central Valley Project Transmission System. Western proposes at a minimum to construct, own, operate, and maintain a new 230-kilovolt (kV) transmission line about 62 miles in length between Western's Tracy Substation and Western's San Luis Substation and a
Chapter 13 - NEUTRON AREA DETECTORS 1. NEUTRON ...
... The neutron peak corresponds to both reaction products being entirely absorbed in the ... 6. A fission chamber is a very low efficiency neutron detector ...
Cold Neutron and Ultracold Neutron Sources
... Moderators � Solid Methane � CH 4 � CD 4 ... In a cold neutron flux with a continuous spectrum, more neutrons could ... Magneto-vibrational Scatt. + ...
Directional Detection of Fast Neutrons Using a Time Projection Chamber
Spontaneous fission in Special Nuclear Material (SNM) such as plutonium and highly enriched uranium (HEU) results in the emission of neutrons with energies in the MeV range (hereafter 'fast neutrons'). These fast neutrons are largely unaffected by the few centimeters of intervening high-Z material that would suffice for attenuating most emitted gamma rays, while tens of centimeters of hydrogenous materials are required to achieve substantial attenuation of neutron fluxes from SNM. Neutron detectors are therefore an important complement to gamma-ray detectors in SNM search and monitoring applications. The rate at which SNM emits fast neutrons varies from about 2 per kilogram per second for typical HEU to some 60,000 per kilogram per second for metallic weapons grade plutonium. These rates can be compared with typical sea-level (cosmogenic) neutron backgrounds of roughly 5 per second per square meter per steradian in the relevant energy range [1]. The fact that the backgrounds are largely isotropic makes directional neutron detection especially attractive for SNM detection. The ability to detect, localize, and ultimately identify fast neutron sources at standoff will ultimately be limited by this background rate. Fast neutrons are particularly well suited to standoff detection and localization of SNM or other fast neutrons sources. Fast neutrons have attenuation lengths of about 60 meters in air, and retain considerable information about their source direction even after one or two scatters. Knowledge of the incoming direction of a fast neutron, from SNM or otherwise, has the potential to significantly improve signal to background in a variety of applications, since the background arriving from any one direction is a small fraction of the total background. Imaging or directional information therefore allows for source detection at a larger standoff distance or with shorter dwell times compared to nondirectional detectors, provided high detection efficiency can be maintained. Directional detection of neutrons has been previously considered for applications such as controlled fusion neutron imaging [2], nuclear fuel safety research [3], imaging of solar neutrons and SNM [4], and in nuclear science [5]. The use of scintillating crystals and fibers has been proposed for directional neutron detection [6]. Recently, a neutron scatter camera has been designed, constructed, and tested for imaging of fast neutrons, characteristic for SNM material fission [7]. The neutron scatter camera relies on the measurement of the proton recoil angle and proton energy by time of flight between two segmented solid-state detectors. A single-measurement result from the neutron scatter camera is a ring containing the possible incident neutron direction. Here we describe the development and commissioning of a directional neutron detection system based on a time projection chamber (TPC) detector. The TPC, which has been widely used in particle and nuclear physics research for several decades, provides a convenient means of measuring the full 3D trajectory, specific ionization (i.e particle type) and energy of charged particles. For this application, we observe recoil protons produced by fast neutron scatters on protons in hydrogen or methane gas. Gas pressures of a few ATM provide reasonable neutron interaction/scattering rates.
Bowden, N; Heffner, M; Carosi, G; Carter, D; Foxe, M; Jovanovic, I
San Andreas Geothermal Region | Open Energy Information
San Andreas Geothermal Region San Andreas Geothermal Region (Redirected from San Andreas) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home San Andreas Geothermal Region Details Areas (4) Power Plants (0) Projects (0) Techniques (1) Map: {{{Name}}} The topographic texture of western California is controlled by the San Andreas fault system, the tectonic expression of the Pacific Plate sliding northwestward along the western margin of the North American Plate. Hundreds of miles long and in places up to a mile wide, the San Andreas Fault Zone has been active since its origin in the Tertiary. About 10 percent of the present plate motion is compressional, shortening and wrinkling the crust to create the parallel coastal northwest-southeast mountain ranges. USGS Physiographic Regions[1]
Iterative Methods for Neutron Transport Eigenvalue Problems
We discuss iterative methods for computing criticality in nuclear reactors. In general this requires the solution of a generalized eigenvalue problem for an unsymmetric integro-differential operator in six independent variables, modeling transport, scattering, ... Keywords: criticality, generalized eigenvalue problem, inexact inverse iteration, neutron transport, symmetry
Fynn Scheben; Ivan G. Graham
A nuclear reactor which uses uranium in the form of elongated tubes as fuel elements and liquid as a coolant is described. Elongated tubular uranium bodies are vertically disposed in an efficient neutron slowing agent, such as graphite, for example, to form a lattice structure which is disposed between upper and lower coolant tanks. Fluid coolant tubes extend through the uranium bodies and communicate with the upper and lower tanks and serve to convey the coolant through the uranium body. The reactor is also provided with means for circulating the cooling fluid through the coolant tanks and coolant tubes, suitable neutron and gnmma ray shields, and control means.
Wigner, E.P.; Weinberg, A.W.; Young, G.J.
2009 Race to San Francisco | ENERGY STAR
9 Race to San Francisco Secondary menu About us Press room Contact Us Portfolio Manager Login Facility owners and managers Existing buildings Commercial new construction Industrial...
DOE Sustainability Assistance Network (SAN) Notes, Thursday,...
Page 1 of 4 DOE Sustainability Assistance Network (SAN) Notes Thursday, November 15, 2012 1. Sustainability Performance Office Highlights Paul Estabrooks, SPO The Sustainability...
California - San Joaquin Basin Onshore Nonassociated Natural...
Gasoline and Diesel Fuel Update (EIA)
Natural Gas, Wet After Lease Separation, Proved Reserves (Billion Cubic Feet) California - San Joaquin Basin Onshore Nonassociated Natural Gas, Wet After Lease Separation,...
Better Buildings Neighborhood Program: San Jose, California,...
Jose, California, Partners With Established Community Groups to Win Over Homeowners to someone by E-mail Share Better Buildings Neighborhood Program: San Jose, California, Partners...
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U.S. Energy Information Administration (EIA) Indexed Site
Name","Description"," Of Series","Frequency","Latest Data for" ,"Data 1","California - San Joaquin Basin Onshore Nonassociated Natural Gas, Wet After Lease Separation,...
San Antonio spurs increase in solar energy production | Department...
San Antonio spurs increase in solar energy production San Antonio spurs increase in solar energy production January 13, 2010 - 4:54pm Addthis San Antonio is using these unique...
San Diego Solar Panels Generate Clean Electricity Along with...
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Solar Fair in San Jos� Tomorrow | Department of Energy
Solar Fair in San Jos Tomorrow Solar Fair in San Jos Tomorrow April 29, 2011 - 12:53pm Addthis Solar panels on display at the the San Jose Solar and Energy Efficiency Fair |...
2012 National Electric Transmission Congestion Study - San Diego...
San Diego Workshop 2012 National Electric Transmission Congestion Study - San Diego Workshop On December 15, 2011, DOE hosted a regional pre-study workshop in San Diego, CA to...
Dr. Michael Agamalian | ORNL Neutron Sciences
Dr. Michael Agamalian Dr. Michael Agamalian Lead Scientist, Ultra-Small-Angle Neutron Scattering (USANS), SNS Education PhD in Physics, St. Petersburg Nuclear Physics Institute, Russia Description of Research Michael Agamalian and collaborators have made important contributions to the development of the ORNL Bonse-Hart Ultra-Small-Angle Neutron Scattering instrument (USANS). In particular, they adopted the classical X-ray Bonse-Hart technique for neutrons by modifying the Si channel-cut crystal and introducing an additional element, a Cd absorber. This innovation, combined with application of a specialized chemical-mechanical treatment of the diffractive surfaces of the Si channel-cut crystal, has increased the sensitivity of the ORNL USANS instrument by three orders of magnitude. This
EIS-0247: Construction and Operation of the Spallation Neutron Source |
247: Construction and Operation of the Spallation Neutron 247: Construction and Operation of the Spallation Neutron Source EIS-0247: Construction and Operation of the Spallation Neutron Source SUMMARY The United States needs a high-flux, short- pulsed neutron source to provide its scientific and industrial research communities with a much more intense source of pulsed neutrons for neutron scattering research than is currently available. This source would assure the availability of a state-of-the-art neutron research facility in the United States in the decades ahead. This facility would be used to conduct research in areas such as materials science, condensed matter physics, the molecular structure of biological materials, properties of polymers and complex fluids, and magnetism. In addition to creating new scientific and
The design of control rods for nuclear reactors are described. In this design the control rod consists essentially of an elongated member constructed in part of a neutron absorbing material and having tube means extending therethrough for conducting a liquid to cool the rod when in use.
Anderson, H.L.
Methods for absorbing neutrons
A conduction cooled neutron absorber may include a metal matrix composite that comprises a metal having a thermal neutron cross-section of at least about 50 barns and a metal having a thermal conductivity of at least about 1 W/cmK. Apparatus for providing a neutron flux having a high fast-to-thermal neutron ratio may include a source of neutrons that produces fast neutrons and thermal neutrons. A neutron absorber positioned adjacent the neutron source absorbs at least some of the thermal neutrons so that a region adjacent the neutron absorber has a fast-to-thermal neutron ratio of at least about 15. A coolant in thermal contact with the neutron absorber removes heat from the neutron absorber.
Guillen, Donna P. (Idaho Falls, ID); Longhurst, Glen R. (Idaho Falls, ID); Porter, Douglas L. (Idaho Falls, ID); Parry, James R. (Idaho Falls, ID)
Review of Multi-messenger observations of neutron rich matter
At very high densities, electrons react with protons to form neutron rich matter. This material is central to many fundamental questions in nuclear physics and astrophysics. Moreover, neutron rich matter is being studied with an extraordinary variety of new tools such as the Facility for Rare Isotope Beams (FRIB) and the Laser Interferometer Gravitational Wave Observatory (LIGO). We describe the Lead Radius Experiment (PREX) that uses parity violating electron scattering to measure the neutron radius of 208Pb. This has important implications for neutron stars and their crusts. We discuss X-ray observations of neutron star radii. These also have important implications for neutron rich matter. Gravitational waves (GW) open a new window on neutron rich matter. They come from sources such as neutron star mergers, rotating neutron star mountains, and collective r-mode oscillations. Using large scale molecular dynamics simulations, we find neutron star crust to be very strong. It can support mountains on rotating neutron stars large enough to generate detectable gravitational waves. Finally, neutrinos from core collapse supernovae (SN) provide another, qualitatively different probe of neutron rich matter. Neutrinos escape from the surface of last scattering known as the neutrino-sphere. This is a low density warm gas of neutron rich matter. Neutrino-sphere conditions can be simulated in the laboratory with heavy ion collisions. Observations of neutrinos can probe nucleosyntheses in SN. We believe that combing astronomical observations using photons, GW, and neutrinos, with laboratory experiments on nuclei, heavy ion collisions, and radioactive beams will fundamentally advance our knowledge of compact objects in the heavens, the dense phases of QCD, the origin of the elements, and of neutron rich matter.
C. J. Horowitz
DOE Science Showcase - Neutron Science Research from DOE Databases | OSTI,
DOE Science Showcase - Neutron Science Research from DOE Databases DOE Science Showcase - Neutron Science Research from DOE Databases Additional neutron science research in DOE Databases Information Bridge Neutron scattering research was pioneered in 1946 by ORNL's Clifford G. Shull, winner of 1994 Nobel Prize in Physics. Access Shull's early research records in Energy Citations Database. Neutron scattering research was pioneered in 1946 by ORNL's Clifford G. Shull, winner of 1994 Nobel Prize in Physics. Access Shull's early research records in Energy Citations Database. Energy Citations Database DOE R&D Accomplishments DOE R&D Project Summaries DOE Data Explorer DOepatents Researchers at DOE labs, including Argonne National Laboratory (ANL), Brookhaven National Laboratory (BNL), and Oak Ridge National Laboratory
California--San Joaquin Basin Onshore Natural Gas Plant Liquids...
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Refraction Survey At San Emidio Desert Area (DOE GTP) | Open...
San Emidio Desert Area (DOE GTP) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Refraction Survey At San Emidio Desert Area (DOE GTP)...
Presentations from San Antonio, Texas Workshop - June 9, 2012...
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Neutron reflecting supermirror structure
An improved neutron reflecting supermirror structure comprising a plurality of stacked sets of bilayers of neutron reflecting materials. The improved neutron reflecting supermirror structure is adapted to provide extremely good performance at high incidence angles, i.e. up to four time the critical angle of standard neutron mirror structures. The reflection of neutrons striking the supermirror structure at a high critical angle provides enhanced neutron throughput, and hence more efficient and economical use of neutron sources.
Wood, James L. (Drayton Plains, MI)
An improved neutron reflecting supermirror structure comprising a plurality of stacked sets of bilayers of neutron reflecting materials. The improved neutron reflecting supermirror structure is adapted to provide extremely good performance at high incidence angles, i.e. up to four time the critical angle of standard neutron mirror structures. The reflection of neutrons striking the supermirror structure at a high critical angle provides enhanced neutron throughput, and hence more efficient and economical use of neutron sources. 2 figs.
Wood, J.L.
TABLE OF CONTENTS 2014 ORNL NEUTRON SCIENCES STRATEGIC PLAN Executive Summary Director's Message Introduction Neutron Scattering User Facilities Comparison with Leading International Neutron Facilities Strategic Planning and Research Community Involvement New Opportunities Science Priorities Introduction Quantum Materials Materials Synthesis and Performance Soft Molecular Matter Biosciences New and Upgraded Capabilities Enabling Technologies Sources Executing the Plan Strategic Timeline Appendices and Acronyms 3 6 17 55 43 51 59 9 3 EXECUTIVE SUMMARY 2014 ORNL NEUTRON SCIENCES STRATEGIC PLAN EXECUTIVE SUMMARY AND DIRECTOR'S MESSAGE * Optimizing existing instrumentation with targeted de-
Use of the WNR spallation neutron source at LAMPF to determine the absolute efficiency of a neutron scintillation detector
Prompt fission neutron spectrum measurements at the University of Massachusetts Lowell 5.5 MV Van de Graaff accelerator laboratory require that the neutron detector efficiency be well known over a neutron energy range of 100 keV to 20 MeV. The efficiency of the detector, has been determined for energies greater than 5.0 MeV using the Weapons Neutron Research (WNR) white neutron source at the Los Alamos Meson Physics Facility (LAMPF) in a pulsed beam, time-of-flight (TOF) experiment. Carbon matched polyethylene and graphite scatterers were used to obtain a hydrogen spectrum. The detector efficiency was determined using the well known H(n,n) scattering cross section. Results are compared to the detector efficiency calculation program SCINFUL available from the Radiation Shielding Information Center at Oak Ridge National Laboratory.
Staples, P.A.; Egan, J.J.; Kegel, G.H.R.; Woodring, M.L.; DeSimone, D.J. [University of Massachusetts, Lowell, MA (United States). Dept. of Physics and Applied Physics; Lisowski, P.W. [Los Alamos National Lab., NM (United States)
EIS-0477: San Juan Basin Energy Connect Project, San Juan County, New
7: San Juan Basin Energy Connect Project, San Juan County, 7: San Juan Basin Energy Connect Project, San Juan County, New Mexico and La Plata County, Colorado EIS-0477: San Juan Basin Energy Connect Project, San Juan County, New Mexico and La Plata County, Colorado SUMMARY The Department of the Interior's Bureau of Land Management is preparing this EIS to evaluate the environmental impacts of a proposal to construct a 230-kilovolt transmission line from the Farmington area in northwest New Mexico to Ignacio, Colorado, to relieve transmission constraints, serve new loads, and offer economic development through renewable energy development in the San Juan Basin. DOE's Western Area Power Administration is a cooperating agency; the proposed transmission line would require an interconnection with Western's Shiprock Substation, near Farmington.
San Andreas Geothermal Region San Andreas Geothermal Region Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home San Andreas Geothermal Region Details Areas (4) Power Plants (0) Projects (0) Techniques (1) Map: {{{Name}}} The topographic texture of western California is controlled by the San Andreas fault system, the tectonic expression of the Pacific Plate sliding northwestward along the western margin of the North American Plate. Hundreds of miles long and in places up to a mile wide, the San Andreas Fault Zone has been active since its origin in the Tertiary. About 10 percent of the present plate motion is compressional, shortening and wrinkling the crust to create the parallel coastal northwest-southeast mountain ranges. USGS Physiographic Regions[1] References ↑ "USGS Physiographic Regions"
Category:San Francisco, CA | Open Energy Information
CA CA Jump to: navigation, search Go Back to PV Economics By Location Media in category "San Francisco, CA" The following 16 files are in this category, out of 16 total. SVFullServiceRestaurant San Francisco CA Southern California Edison Co.png SVFullServiceRestauran... 71 KB SVMidriseApartment San Francisco CA Southern California Edison Co.png SVMidriseApartment San... 65 KB SVPrimarySchool San Francisco CA Southern California Edison Co.png SVPrimarySchool San Fr... 70 KB SVQuickServiceRestaurant San Francisco CA Southern California Edison Co.png SVQuickServiceRestaura... 66 KB SVSecondarySchool San Francisco CA Southern California Edison Co.png SVSecondarySchool San ... 65 KB SVStandAloneRetail San Francisco CA Southern California Edison Co.png SVStandAloneRetail San...
Alternative Fuels Data Center: San Diego Leads in Promoting EVs
Alternative Fuels and Advanced Vehicles Data Center (EERE)
San Diego Leads in San Diego Leads in Promoting EVs to someone by E-mail Share Alternative Fuels Data Center: San Diego Leads in Promoting EVs on Facebook Tweet about Alternative Fuels Data Center: San Diego Leads in Promoting EVs on Twitter Bookmark Alternative Fuels Data Center: San Diego Leads in Promoting EVs on Google Bookmark Alternative Fuels Data Center: San Diego Leads in Promoting EVs on Delicious Rank Alternative Fuels Data Center: San Diego Leads in Promoting EVs on Digg Find More places to share Alternative Fuels Data Center: San Diego Leads in Promoting EVs on AddThis.com... Sept. 3, 2011 San Diego Leads in Promoting EVs W atch how San Diego is leading the way in promoting electric vehicles. For information about this project, contact San Diego Regional Clean Cities
Physics design of a cold neutron source for KIPT neutron source facility.
Argonne National Laboratory (ANL) of USA and Kharkov Institute of Physics and Technology (KIPT) of Ukraine have been collaborating on the conceptual design development of a neutron source facility. It is based on the use of an electron accelerator driven subcritical (ADS) facility with low enriched uranium fuel, using the existing electron accelerators at KIPT of Ukraine [1]. The neutron source of the subcritical assembly is generated from the interaction of 100-KW electron beam, which has a uniform spatial distribution and the electron energy in the range of 100 to 200 MeV, with a natural uranium target [2]. The main functions of the facility are the production of medical isotopes and the support of the Ukraine nuclear power industry. Neutron beam experiments and material studies are also included. Over the past two-three decades, structures with characteristic lengths of 100 {angstrom} and correspondingly smaller vibrational energies have become increasingly important for both science and technology [3]. The characteristic dimensions of the microstructures can be well matched by neutrons with longer vibrational wavelength and lower energy. In the accelerator-driven subcritical facility, most of the neutrons are generated from fission reactions with energy in the MeV range. They are slowed down to the meV energy range through scattering reactions in the moderator and reflector materials. However, the fraction of neutrons with energies less than 5 meV in a normal moderator spectrum is very low because of up-scattering caused by the thermal motion of moderator or reflector molecules. In order to obtain neutrons with energy less than 5 meV, cryogenically cooled moderators 'cold neutron sources' should be used to slow down the neutrons. These cold moderators shift the neutron energy spectrum down because the thermal motion of moderator molecules as well as the up-scattering is very small, which provides large gains in intensity of low energy neutrons, E neutron source could provide the neutrons beams with lower energy, which could be utilized in scattering experiment and material structures analysis. This study describes the performed physics analyses to define and characterize the cold neutron source of the KIPT neutron source facility. The cold neutron source is designed to optimize the cold neutron brightness to the experimental instruments outside the radial heavy concrete shield of the facility. Liquid hydrogen or solid methane with 20 K temperature is used as a cold moderator. Monte Carlo computer code MCNPX [4], with ENDF/B-VI nuclear data libraries, is utilized to calculate the cold neutron source performance and estimate the nuclear heat load to the cold moderator. The surface source generation capability of MCNPX code has been used to provide the possibility of analyzing different design configurations and perform design optimization analyses with reasonable computer resources. Several design configurations were analyzed and their performance were characterized and optimized.
Zhong, Z.; Gohar, Y.; Kellogg, R.; Nuclear Engineering Division
Argonne National Laboratory (ANL) of USA and Kharkov Institute of Physics and Technology (KIPT) of Ukraine have been collaborating on the conceptual design development of a neutron source facility. It is based on the use of an electron accelerator driven subcritical (ADS) facility with low enriched uranium fuel, using the existing electron accelerators at KIPT of Ukraine [1]. The neutron source of the subcritical assembly is generated from the interaction of 100-KW electron beam, which has a uniform spatial distribution and the electron energy in the range of 100 to 200 MeV, with a natural uranium target [2]. The main functions of the facility are the production of medical isotopes and the support of the Ukraine nuclear power industry. Neutron beam experiments and material studies are also included. Over the past two-three decades, structures with characteristic lengths of 100 {angstrom} and correspondingly smaller vibrational energies have become increasingly important for both science and technology [3]. The characteristic dimensions of the microstructures can be well matched by neutrons with longer vibrational wavelength and lower energy. In the accelerator-driven subcritical facility, most of the neutrons are generated from fission reactions with energy in the MeV range. They are slowed down to the meV energy range through scattering reactions in the moderator and reflector materials. However, the fraction of neutrons with energies less than 5 meV in a normal moderator spectrum is very low because of up-scattering caused by the thermal motion of moderator or reflector molecules. In order to obtain neutrons with energy less than 5 meV, cryogenically cooled moderators 'cold neutron sources' should be used to slow down the neutrons. These cold moderators shift the neutron energy spectrum down because the thermal motion of moderator molecules as well as the up-scattering is very small, which provides large gains in intensity of low energy neutrons, E < 5 meV. The accelerator driven subcritical facility is designed with a provision to add a cryogenically cooled moderator system. This cold neutron source could provide the neutrons beams with lower energy, which could be utilized in scattering experiment and material structures analysis. This study describes the performed physics analyses to define and characterize the cold neutron source of the KIPT neutron source facility. The cold neutron source is designed to optimize the cold neutron brightness to the experimental instruments outside the radial heavy concrete shield of the facility. Liquid hydrogen or solid methane with 20 K temperature is used as a cold moderator. Monte Carlo computer code MCNPX [4], with ENDF/B-VI nuclear data libraries, is utilized to calculate the cold neutron source performance and estimate the nuclear heat load to the cold moderator. The surface source generation capability of MCNPX code has been used to provide the possibility of analyzing different design configurations and perform design optimization analyses with reasonable computer resources. Several design configurations were analyzed and their performance were characterized and optimized.
California - San Joaquin Basin Onshore Crude Oil Estimated ...
U.S. Energy Information Administration (EIA)
California - San Joaquin Basin Onshore Crude Oil Estimated Production from Reserves (Million Barrels)
WAND: Wide-Angle Neutron Diffractometer at HFIR | ORNL Neutron Sciences
US/Japan Wide-Angle Neutron Diffractometer US/Japan Wide-Angle Neutron Diffractometer WAND Instrument scientist Jaime Fernandez-Baca (left) with a visiting researcher at WAND. The Wide-Angle Neutron Diffractometer (WAND) at the HFIR HB-2C beam tube was designed to provide two specialized data-collection capabilities: (1) fast measurements of medium-resolution powder-diffraction patterns and (2) measurements of diffuse scattering in single crystals using flat-cone geometry. For these purposes, this instrument is equipped with a curved, one-dimensional 3He position-sensitive detector covering 125º of the scattering angle with the focal distance of 71 cm. The sample and detector can be tilted in the flat-cone geometry mode. These features enable measurement of single-crystal diffraction patterns in a short time over a
Joint Institute for Neutron Sciences | ornl.gov
Joint Institute for Neutron Sciences Joint Institute for Neutron Sciences SHARE Joint Institute for Neutron Sciences JINS is located on Chestnut Ridge within the 80-acre SNS site, part of Oak Ridge National Laboratory. The Joint Institute for Neutron Sciences (JINS) was founded as a collaborative effort between Oak Ridge National Laboratory (ORNL) and The University of Tennessee to promote the use of neutron scattering in various fields of research. Through worldwide collaborations between researchers of the biological and life sciences, energy sciences, polymer science, condensed matter physics and computational sciences, a synergistic consortium will be created at ORNL to elevate the field of neutron sciences to a new level of efficacy for industry, medicine and frontier research. The goal of JINS is to serve as a gateway for users of the Spallation
Mixed field dosimetry of epithermal neutron beams for boron neutron capture therapy at the MITR-II research reactor
During the past several years, there has been growing interest in Boron Neutron Capture Therapy (BNCT) using epithermal neutron beams. The dosimetry of these beams is challenging. The incident beam is comprised mostly of epithermal neutrons, but there is some contamination from photons and fast neutrons. Within the patient, the neutron spectrum changes rapidly as the incident epithermal neutrons scatter and thermalize, and a photon field is generated from neutron capture in hydrogen. In this paper, a method to determine the doses from thermal and fast neutrons, photons, and the B-10([ital n],[alpha])Li-7 reaction is presented. The photon and fast neutron doses are measured with ionization chambers, in realistic phantoms, using the dual chamber technique. The thermal neutron flux is measured with gold foils using the cadmium difference technique; the thermal neutron and B-10 doses are determined by the kerma factor method. Representative results are presented for a unilateral irradiation of the head. Sources of error in the method as applied to BNCT dosimetry, and the uncertainties in the calculated doses are discussed.
Rogus, R.D.; Harling, O.K.; Yanch, J.C. (Massachusetts Institute of Technology, Nuclear Reactor Laboratory, Cambridge, Massachusetts 02139 (United States))
Federal Energy Management Program: National Park Service - San Miguel
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Cold-moderator scattering kernel methods
An accurate representation of the scattering of neutrons by the materials used to build cold sources at neutron scattering facilities is important for the initial design and optimization of a cold source, and for the analysis of experimental results obtained using the cold source. In practice, this requires a good representation of the physics of scattering from the material, a method to convert this into observable quantities (such as scattering cross sections), and a method to use the results in a neutron transport code (such as the MCNP Monte Carlo code). At Los Alamos, the authors have been developing these capabilities over the last ten years. The final set of cold-moderator evaluations, together with evaluations for conventional moderator materials, was released in 1994. These materials have been processed into MCNP data files using the NJOY Nuclear Data Processing System. Over the course of this work, they were able to develop a new module for NJOY called LEAPR based on the LEAP + ADDELT code from the UK as modified by D.J. Picton for cold-moderator calculations. Much of the physics for methane came from Picton`s work. The liquid hydrogen work was originally based on a code using the Young-Koppel approach that went through a number of hands in Europe (including Rolf Neef and Guy Robert). It was generalized and extended for LEAPR, and depends strongly on work by Keinert and Sax of the University of Stuttgart. Thus, their collection of cold-moderator scattering kernels is truly an international effort, and they are glad to be able to return the enhanced evaluations and processing techniques to the international community. In this paper, they give sections on the major cold moderator materials (namely, solid methane, liquid methane, and liquid hydrogen) using each section to introduce the relevant physics for that material and to show typical results.
Contact ORNL Neutron Sciences
Sciences Organization Charts Neutron Sciences Directorate Associate Laboratory Director for Neutron Sciences, Kelly Beierschmitt Biology and Soft Matter Division Director, Paul...
Ultracold-neutron production in a pulsed-neutron beam line
We present the results of an ultracold neutron (UCN) production experiment in a pulsed-neutron beam line at the Los Alamos Neutron Scattering Center. The experimental apparatus allows for a comprehensive set of measurements of UCN production as a function of target temperature, incident neutron energy, target volume, and applied magnetic field. However, the low counting statistics of the UCN signal can be overwhelmed by the large background associated with the scattering of the primary cold-neutron flux that is required for UCN production. We have developed a background subtraction technique that takes advantage of the very different time-of-flight profiles between the UCN and the cold neutrons, in the pulsed beam. Using the unique timing structure, we can reliably extract the UCN signal. Solid ortho-{sup 2}H{sub 2} is used to calibrate UCN transmission through the apparatus, which is designed primarily for studies of UCN production in solid O{sub 2}. In addition to setting the overall detection efficiency in the apparatus, UCN production data using solid {sup 2}H{sub 2} suggest that the UCN upscattering cross section is smaller than previous estimates, indicating the deficiency of the incoherent approximation widely used to estimate inelastic cross sections in the thermal and cold regimes.
Lavelle, C. M.; Liu, C.-Y.; Fox, W.; Manus, G.; McChesney, P. M.; Salvat, D. J.; Shin, Y.; Makela, M.; Morris, C.; Saunders, A.; Couture, A.; Young, A. R. [Physics Department, Indiana University, Bloomington, Indiana 47408 (United States); Physics Division, P25, Los Alamos National Laboratory, Los Alamos, New Mexico 87544 (United States); LANSCE Division, Nuclear Science, Los Alamos National Laboratory, Los Alamos, New Mexico 87544 (United States); Physics Department, North Carolina State University, Raleigh, North Carolina 27695 (United States)
A neutron source of the antimony--beryllium type is presented. The source is comprised of a solid mass of beryllium having a cylindrical recess extending therein and a cylinder containing antimony-124 slidably disposed within the cylindrical recess. The antimony cylinder is encased in aluminum. A berylliunn plug is removably inserted in the open end of the cylindrical recess to completely enclose the antimony cylinder in bsryllium. The plug and antimony cylinder are each provided with a stud on their upper ends to facilitate handling remotely.
Reardon, W.A.; Lennox, D.H.; Nobles, R.G.
2011 Neutron School Attendees
California, San Diego Physics, Condensed Matter 33 Luke Marshall University of Texas at Austin Clean Energy Materials 34 Maria Matthews Pennsylvania State University Physics,...
Spallation Neutron Source | ORNL Neutron Sciences
Spallation Neutron Source SNS site, Spring 2012 The 80-acre SNS site is located on the east end of the ORNL campus and is about a three-minute drive from her sister neutron...
Deeply Virtual Neutrino Scattering
We investigate the extension of the deeply virtual Compton scattering process into the weak interaction sector.
Ales Psaker
Nonrelativistic Description of Nucleon-Nucleus Scattering
Within the three-dimensional semiclassical approximation, an analytic expression is obtained for the amplitude of proton-nucleus scattering at intermediate energies of incident protons. The method for deriving this amplitude is based on the use of the high-energy approximation with distorted waves. In view of the short-range character of proton-nucleon interaction, the process of proton-nucleus scattering is represented as a series of single scattering events occurring on each individual nucleon. With the aid of the proposed mathematical formalism, a recursion relation is derived that makes it possible to express the nuclear form factor obtained within the distorted-wave method in terms of the sum of an infinite Born series. Parameters that characterize the distributions of protons and neutrons in the spherical nuclei {sup 40}Ca, {sup 48}Ca, {sup 90}Zr, and {sup 208}Pb and which include the width of the surface layer of nucleons and the root-mean-square radii of the proton-, neutron-, and nucleon-density distributions are determined from an analysis of the measured cross sections for the elastic scattering of 1-GeV protons, a modified Fermi function being employed for the nucleon-density distribution.
Mirabutalybov, M.M. [Azerbaijan State Petroleum Academy, pr. Azadlyg 20, Baku, 370010 (Azerbaijan)
Chemical & EngChemical/Engineering Materials Division | Neutron Science |
Chemical and Engineering Materials Division Chemical and Engineering Materials Division SHARE Chemical and Engineering Materials Division CEMD Director Mike Simonson The Chemical and Engineering Materials Division (CEMD) supports neutron-based research at SNS and HFIR in understanding the structure and dynamics of chemical systems and novel engineering materials. The user community takes advantage of division-supported capabilities of neutron scattering for measurements over wide ranges of experimental and operating conditions, including studies of chemical and physical changes in situ. User experiments with diffraction, small-angle scattering, inelastic and quasielastic scattering, and neutron imaging instruments address a range of problems in chemistry and in engineering materials research. Current areas of research supported by the division include the structure
San Jacinto Wind Farm | Open Energy Information
San Jacinto Wind Farm San Jacinto Wind Farm Facility San Jacinto Sector Wind energy Facility Type Commercial Scale Wind Facility Status In Service Owner SeaWest Developer SeaWest Energy Purchaser Southern California Edison Co Location San Gorgonio CA Coordinates 33.9095°, -116.734° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":33.9095,"lon":-116.734,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}
Sustainability Assistance Network (SAN), Monthly Conference Call...
Sustainability Assistance Network (SAN) Monthly Conference Call Thursday, June 16, 2011 11:00 am - 12:30 pm (EST) Dial-in U.S. Toll: 303-248-0285 Access Code: 5863657 Web Login...
Sustainability Assistance Network (SAN) Monthly Conference Call Thursday, August 16, 2012 11:00 am - 12:30 pm (ET) Dial-in U.S. Toll: 303-248-0285 Access Code: 5863657 Web Login...
Sustainability Assistance Network (SAN) Monthly Conference Call...
Sustainability Assistance Network (SAN) Monthly Conference Call Thursday, April 26, 2012 11:00 am - 12:30 pm (ET) Dial-in U.S. Toll: 303-248-0285 Access Code: 5863657 Web Login...
Sustainability Assistance Network (SAN) Monthly Conference Call Thursday, August 18, 2011 11:00 am - 12:30 pm (EST) Dial-in U.S. Toll: 303-248-0285 Access Code: 5863657 Web Login...
Sustainability Assistance Network (SAN) Monthly Conference Call Thursday, November 17, 2011 11:00 am - 12:30 pm (EST) Dial-in U.S. Toll: 303-248-0285 Access Code: 5863657 Web Login...
Sustainability Assistance Network (SAN) Monthly Conference Call Thursday, September 20, 2012 11:00 am - 12:30 pm (ET) Dial-in U.S. Toll: 303-248-0285 Access Code: 5863657 Web Login...
Sustainability Assistance Network (SAN) Monthly Conference Call Thursday, November 15, 2012 11:00 am - 12:30 pm (ET) Dial-in U.S. Toll: 303-248-0285 Access Code: 5863657 Web Login...
Sustainability Assistance Network (SAN) Monthly Conference Call Thursday, July 19, 2012 11:00 am - 12:30 pm (ET) Dial-in U.S. Toll: 303-248-0285 Access Code: 5863657 Web Login...
Sustainability Assistance Network (SAN) Monthly Conference Call Thursday, October 20, 2011 11:00 am - 12:30 pm (EST) Dial-in U.S. Toll: 303-248-0285 Access Code: 5863657 Web Login...
Sustainability Assistance Network (SAN) Monthly Conference Call Thursday, June 21, 2012 11:00 am - 12:30 pm (ET) Dial-in U.S. Toll: 303-248-0285 Access Code: 5863657 Web Login...
Sustainability Assistance Network (SAN) Monthly Conference Call Thursday, September 15, 2011 11:00 am - 12:30 pm (EST) Dial-in U.S. Toll: 303-248-0285 Access Code: 5863657 Web...
Sustainability Assistance Network (SAN) Monthly Conference Call Thursday, December 20, 2012 11:00 am - 12:30 pm (ET) Dial-in U.S. Toll: 303-248-0285 Access Code: 5863657 Web Login...
Sustainability Assistance Network (SAN) Monthly Conference Call Thursday, June 20, 2013 11:00 am - 12:30 pm (ET) Dial-in U.S. Toll: 303-248-0285 Access Code: 5863657 Web Login:...
Sustainability Assistance Network (SAN) Monthly Conference Call Thursday, December 15, 2011 11:00 am - 12:30 pm (EST) Dial-in U.S. Toll: 303-248-0285 Access Code: 5863657 Web Login...
Sustainability Assistance Network (SAN) Monthly Conference Call Thursday, March 15, 2012 11:00 am - 12:30 pm (EST) Dial-in U.S. Toll: 303-248-0285 Access Code: 5863657 Web Login...
Sustainability Assistance Network (SAN) Monthly Conference Call Thursday, May 16, 2013 11:00 am - 12:30 pm (ET) Dial-in U.S. Toll: 303-248-0285 Access Code: 5863657 Web Login...
Sustainability Assistance Network (SAN) Monthly Conference Call Thursday, October 18, 2012 11:00 am - 12:30 pm (ET) Dial-in U.S. Toll: 303-248-0285 Access Code: 5863657 Web Login...
Sustainability Assistance Network (SAN) Monthly Conference Call Thursday, February 21, 2013 11:00 am - 12:30 pm (ET) Dial-in U.S. Toll: 303-248-0285 Access Code: 5863657 Web Login...
City of San Antonio- Green Building Requirement
Energy.gov (U.S. Department of Energy (DOE))
In 2009 San Antonio announced [http://www.sanantonio.gov/oep/SustainabilityPlan.asp Mission Verde], which outlines eleven initiatives for a sustainable economy. As part of this plan, the City...
San Francisco Distributed Energy Resources Testbed
feeder serving a publicly-owned sewage treatment plant with a 1.95 MW cogeneration facility and 255 kW solar array. San Francisco Community Power, a nonprofit...
NPP Tropical Forest: San Eusebio, Venezuela
Eusebio, Venezuela, 1970-1971 PHOTOGRAPH Photograph: General view of the San Eusebio site (click on the photo to view a series of images from this site) Data Citation Cite this...
City of San Diego- Sustainable Building Policy
The City of San Diego�s Sustainable Building Policy is directed by Council Policy 900-14. The policy contains regulations regarding building measures, private-sector incentives, health and...
Hydrogen absorption in epitaxial W/Nb(001) and polycrystalline Fe/Nb(110) multilayers studied in-situ by X-ray/neutron scattering techniques and X-ray absorption spectroscopy
Hydrogen can be absorbed in large quantities by 100 {angstrom} thin Nb layers embedded in epitaxial W/Nb and polycrystalline Fe/Nb multilayers. The solubility and the hydrogen-induced structural changes of the host lattice are explored in-situ by small-angle neutron/X-ray reflectometry and high-angle diffraction. These measurements reveal for both systems that the relative out-of-plane expansion of the Nb layers is considerably larger than the relative increase of the Nb interplanar spacing indicating two distinctly different mechanisms of hydrogen absorption. In Fe/Nb multilayers, hydrogen expands the Nb interplanar spacing in a continuous way as function of the external pressure. In contrast, the Nb lattice expansion is discontinuous in epitaxial W/Nb multilayers: A jump in the Nb(002) Bragg reflection position occurs at a critical hydrogen pressure of 1 mbar. In-situ EXAFS spectroscopy also exhibits an irreversible expansion of the Nb lattice in the film plane for p{sub H{sub 2}}> 1 mbar. This can be regarded as a structural phase transition from an exclusively out-of-plane to a three-dimensionally expanded state at low and high hydrogen pressures, respectively.
Klose, F.; Rehm, C.; Fieber-Erdmann, M.; Holub-Krappe, E.; Bleif, H. J.; Sowers, H.; Goyette, R.; Troger, L.; Maletta, H.
Reflected Neutron Effects in Multiplicity Measurements of Bare HEU Assemblies
In a passive multiplicity characterization of highly enriched uranium (HEU) assemblies, fission chains are initiated by the characteristically fast neutrons from spontaneous fission of {sup 238}U and {sup 235}U as well as cosmic-ray spallation neutrons. Active interrogation of HEU uses other physical mechanisms for starting chains by inducing fission from high-energy neutrons, high-energy gamma-rays, delayed neutrons, or thermal neutrons. In all cases a contribution to the initiation of fission chains is the reflection of neutrons that initially escape the assembly and re-enter it after undergoing some scattering. The reflected neutron flux is geometry dependent and a combination of fast and thermal energies. The reflected thermal neutron contribution occurs hundreds of microseconds after the beginning of the fission chain and can be distinguished from the cosmic-ray spallation neutrons unrelated to fission chains, resulting in an HEU detection signature with high signal-to-noise. However, the reflected thermal neutron flux can be eliminated with an efficient thermal neutron absorber to investigate reflected neutron effects. In this paper, active and passive multiplicity measurements with HEU oxide assemblies of up to 16 kg of fuel pins and HEU metal assemblies of up to five 18 kg storage castings are reported. Each case demonstrates the differences in HEU signature when a borated thermal neutron absorber is present and shows the various detectable signatures with 3He proportional counters, the standard detector for differential die-way and neutron multiplicity measurements, and liquid scintillators, a detector capable of operating on the timescale of fission chains.
McConchie, Seth M [ORNL; Hausladen, Paul [ORNL; Mihalczo, John T [ORNL
Literature survey of chemical analysis by thermal neutron induced capture gamma ray spectrometry
A brief discussion of the principles and techniques of chemical analysis by neutron capture gamma radiation is presented, and the widely scattered literature is collected into a single table arranged by element measured.
Gladney, E.S.
Total Scattering Developments for Total Scattering ...
... Density Functional Theory Molecular Dynamics ... of nuclear scattering from different nuclei in a sample) Large when energy nuclei in a sample). ...
Souleymane Omar Diallo | ORNL Neutron Sciences
Souleymane Omar Diallo Souleymane Omar Diallo Quantum Condensed Matter Division Education Ph.D. Physics, University of Delaware, Newark, DE, USA (2007). BSc. Physics, Université Cadi-Ayyad, Marrakesh, Morocco (1999). Description of Research Dynamics of Water in Confinement, Proteins Dynamics, Porous Materials, Neutron and X-ray Scattering, Soft Condensed Matter Physics, Supefluidity and Superconductivity, Quantum Fluids and Solids, Ferroelectricity. Selected Publications J. Charmichael and S.O. Diallo, "A cryogenic high pressure cell for neutron scattering measurements of quantum fluids and solids", submitted Review of Scientific Instruments (2012) S.O. Diallo, E. Mamontov, S. Inagaki, Y. Fukushima, and N. Wada, "Enhanced Translational Dynamics of Water under Electric Field" Phys.
A method is presented for loading and unloading rod type fuel elements of a neutronic reactor of the heterogeneous, solld moderator, liquid cooled type. In the embodiment illustrated, the fuel rods are disposed in vertical coolant channels in the reactor core. The fuel rods are loaded and unloaded through the upper openings of the channels which are immersed in the coolant liquid, such as water. Unloading is accomplished by means of a coffer dam assembly having an outer sleeve which is placed in sealing relation around the upper opening. A radiation shield sleeve is disposed in and reciprocable through the coffer dam sleeve. A fuel rod engaging member operates through the axial bore in the radiation shield sleeve to withdraw the fuel rod from its position in the reactor coolant channel into the shield, the shield snd rod then being removed. Loading is accomplished in the reverse procedure.
Wigner, E.P.; Young, G.J.
An improved neutron reflecting supermirror structure comprising a plurality of stacked sets of bilayers of neutron reflecting materials. The improved neutron reflecting supermirror structure is adapted to provide extremely good performance at high incidence angles, i.e. up to four time the critical angle of standard neutron mirror structures. The reflection of neutrons striking the supermirror structure at a high critical angle provides enhanced neutron throughput, and hence more efficient and economical use of neutron sources. One layer of each set of bilayers consist of titanium, and the second layer of each set of bilayers consist of an alloy of nickel with carbon interstitially present in the nickel alloy.
Features 2011 | ornl.gov
are using a combination of fluorescence and small-angle neutron scattering (SANS) techniques to assist biochemists in better understanding how a protein associated with...
The Versatile Neutron Imaging Instrument at SNS | ORNL Neutron...
The Versatile Neutron Imaging Instrument at SNS VENUS: Neutron imaging to advance energy efficiency VENUS: Neutron imaging to advance energy efficiency. As its name indicates,...
Neutron Energy Spectrum Measurements with a Compact Liquid Scintillation Detector on EAST
A neutron detector based on EJ301 liquid scintillator has been employed at EAST to measure the neutron energy spectrum for D-D fusion plasma. The detector was carefully characterized in different quasi-monoenergetic neutron fields generated by a 4.5 MV Van de Graaff accelerator. In recent experimental campaigns, due to the low neutron yield at EAST, a new shielding device was designed and located as close as possible to the tokamak to enhance the count rate of the spectrometer. The fluence of neutrons and gamma-rays was measured with the liquid neutron spectrometer and was consistent with 3He proportional counter and NaI (Tl) gamma-ray spectrometer measurements. Plasma ion temperature values were deduced from the neutron spectrum in discharges with lower hybrid wave injection and ion cyclotron resonance heating. Scattered neutron spectra were simulated by the Monte Carlo transport Code, and they were well verified by the pulse height measurements at low energies.
Xi Yuan; Xing Zhang; Xufei Xie; G. Gorini; Zhongjing Chen; Xingyu Peng; Jinxiang Chen; Guohui Zhang; Tieshuan Fan; Guoqiang Zhong; Liqun Hu; Baonian Wan
2010 Neutron Review: ORNL Neutron Sciences Progress Report
During 2010, the Neutron Sciences Directorate focused on producing world-class science, while supporting the needs of the scientific community. As the instrument, sample environment, and data analysis tools at High Flux Isotope Reactor (HFIR ) and Spallation Neutron Source (SNS) have grown over the last year, so has promising neutron scattering research. This was an exciting year in science, technology, and operations. Some topics discussed are: (1) HFIR and SNS Experiments Take Gordon Battelle Awards for Scientific Discovery - Battelle Memorial Institute presented the inaugural Gordon Battelle Prizes for scientific discovery and technology impact in 2010. Battelle awards the prizes to recognize the most significant advancements at national laboratories that it manages or co-manages. (2) Discovery of Element 117 - As part of an international team of scientists from Russia and the United States, HFIR staff played a pivotal role in the discovery by generating the berkelium used to produce the new element. A total of six atoms of ''ununseptium'' were detected in a two-year campaign employing HFIR and the Radiochemical Engineering Development Center at Oak Ridge National Laboratory (ORNL) and the heavy-ion accelerator capabilities at the Joint Institute for Nuclear Research in Dubna, Russia. The discovery of the new element expands the understanding of the properties of nuclei at extreme numbers of protons and neutrons. The production of a new element and observation of 11 new heaviest isotopes demonstrate the increased stability of super-heavy elements with increasing neutron numbers and provide the strongest evidence to date for the existence of an island of enhanced stability for super-heavy elements. (3) Studies of Iron-Based High-Temperature Superconductors - ORNL applied its distinctive capabilities in neutron scattering, chemistry, physics, and computation to detailed studies of the magnetic excitations of iron-based superconductors (iron pnictides and chalcogenides), a class of materials discovered in 2008. This research is yielding new insights into the relationship between magnetism and superconductivity and has established several key features of this family of high-temperature superconducting (HTS ) materials: the maximum magnetic field at which they can function, the nature of the electrons involved in the superconductivity, the dependence of the properties upon chemical substitution, and the character of the magnetic fluctuations in the material. The results suggest that despite important differences between these materials and the HTS copper oxides, a universal mechanism may be responsible for the unconventional superconductivity. (4) Coal Sequestration Research: A New Home for Greenhouse Gases - One possibility for slowing down the increasing levels of carbon dioxide (CO{sub 2}) in the atmosphere is to capture the gas in natural underground features such as coal seams. Critical to the feasibility of this technology is determining how much CO{sub 2} can be stored, no method for which has been found - until now. (5) Accelerator Reliability Passes 92% - In December 2010, SNS set a new record for itself when the accelerator ran at 1 MW with 100% reliability. Target Performance Exceeds All Expectations - The mercury target used at SNS is the first of its kind. During the design and planning for SNS, many people were skeptical that the target would work. In 2010, it was confirmed that the target was working not only well but much better than anyone would have imagined. (6) Changing the World of Data Acquisition - Researchers at SNS are starting to benefit from event-based data analysis. Event data mode captures and stores an individual data set for every single neutron that strikes a detector - precisely when and where the neutron is detected. This technique provides numerous advantages over traditional methods. Event data mode allows researchers to process their data at the highest resolution possible with no loss of data. This method of data collection provides a much more efficient way for users to gather data a
Bardoel, Agatha A [ORNL; Counce, Deborah Melinda [ORNL; Ekkebus, Allen E [ORNL; Horak, Charlie M [ORNL; Nagler, Stephen E [ORNL; Kszos, Lynn A [ORNL
Directorate Organization | ORNL Neutron Sciences
ORNL Neutron Sciences Directorate The Neutron Sciences Directorate (NScD) manages and operates the Spallation Neutron Source and the High Flux Isotope Reactor, two of the world's...
Design of the Mechanical Parts for the Neutron Guide System at HANARO
The research reactor HANARO (High-flux Advanced Neutron Application ReactOr) in Korea will be equipped with a neutron guide system, in order to transport cold neutrons from the neutron source to the neutron scattering instruments in the neutron guide hall near the reactor building. The neutron guide system of HANARO consists of the in-pile plug assembly with in-pile guides, the primary shutter with in-shutter guides, the neutron guides in the guide shielding room with dedicated secondary shutters, and the neutron guides connected to the instruments in the neutron guide hall. Functions of the in-pile plug assembly are to shield the reactor environment from nuclear radiation and to support the neutron guides and maintain them precisely oriented. The primary shutter is a mechanical structure to be installed just after the in-pile plug assembly, which stops neutron flux on demand. This paper describes the design of the in-pile assembly and the primary shutter for the neutron guide system at HANARO. The design of the guide shielding assembly for the primary shutter and the neutron guides is also presented.
Shin, J. W.; Cho, Y. G.; Cho, S. J.; Ryu, J. S. [Korea Atomic Energy Research Institute, 1045 Daedeok-daero, Yuseong-gu, Daejeon 305-353 (Korea, Republic of)
Neutron Science TeraGrid Gateway
The unique contributions of the Neutron Science TeraGrid Gateway (NSTG) are the connection of national user facility instrument data sources to the integrated cyberinfrastructure of the National Science FoundationTeraGrid and the development of a neutron science gateway that allows neutron scientists to use TeraGrid resources to analyze their data, including comparison of experiment with simulation. The NSTG is working in close collaboration with the Spallation Neutron Source (SNS) at Oak Ridge as their principal facility partner. The SNS is a next-generation neutron source. It has completed construction at a cost of $1.4 billion and is ramping up operations. The SNS will provide an order of magnitude greater flux than any previous facility in the world and will be available to all of the nation's scientists, independent of funding source, on a peer-reviewed merit basis. With this new capability, the neutron science community is facing orders of magnitude larger data sets and is at a critical point for data analysis and simulation. There is a recognized need for new ways to manage and analyze data to optimize both beam time and scientific output. The TeraGrid is providing new capabilities in the gateway for simulations using McStas and a fitting service on distributed TeraGrid resources to improved turnaround. NSTG staff are also exploring replicating experimental data in archival storage. As part of the SNS partnership, the NSTG provides access to gateway support, cyberinfrastructure outreach, community development, and user support for the neutron science community. This community includes not only SNS staff and users but extends to all the major worldwide neutron scattering centers.
Lynch, Vickie E [ORNL; Chen, Meili [ORNL; Cobb, John W [ORNL; Kohl, James Arthur [ORNL; Miller, Stephen D [ORNL; Speirs, David A [ORNL; Vazhkudai, Sudharshan S [ORNL
Using polarized Neutrons for elastic and dynamic studies on protein systems
We report about measurements at the new Neutron Resonance Spin Echo (NRSE) instrument RESEDA (FRM II, Munich). We have performed polarization analysis, providing information about the fraction of neutrons scattered without and with spin flip at the sample. From comparison with the resolution function measured on a standard sample, the dynamics of the incoherent fraction is detected by NRSE measurements at low temperatures.
Haeussler, W. [Forschungsneutronenquelle Heinz Maier-Leibnitz (FRM II), Technische Universitaet Muenchen, D-85747 Garching (Germany); Physik-Department E21, Technische Universitaet Muenchen, D-85747 Garching (Germany); Kindervater, J. [Forschungsneutronenquelle Heinz Maier-Leibnitz (FRM II), Technische Universitaet Muenchen, D-85747 Garching (Germany)
Neutron time behavior for deuterium neutral beam injection into a hydrogen plasma in ORMAK
Neutrons were produced by D-D interactions when a 28-keV deuterium beam was coinjected into a hydrogen plasma in the Oak Ridge Tokamak (ORMAK). Fokker-Planck calculations, which correctly predict the time behavior of the neutron rate after beam turnon, show that the majority of the neutrons are from injected particles interacting with previously injected deuterons that have scattered to pitch angles of approximately 60 to 90/sup 0/ while slowing down.
England, A. C.; Howe, H. C.; Mihalczo, J. T.; Fowler, R. H.
Publications from Research Conducted at IMAGING | ORNL Neutron Sciences
Publications from Research Conducted at IMAGING Publications from Research Conducted at IMAGING 2013 Publications Barnett A. K., Cox M. N., Crow L., Diawara Y., Funk L. L., Hayward Jason P., Menhard K., Sedov V. N., "A high count rate neutron beam monitor for neutron scattering facilities", IEEE Transactions on Nuclear Science 60, 668-670 (2013). Bingham P., Polsky Y., Anovitz L., "Neutron imaging for geothermal energy systems", Proceedings of the SPIE 8661, 86610K (2013). Kang M., "Hydraulic properties of variably-saturated porous media determined using quantitative neutron radiography", University of Tennessee , (2013). Kang M., Bilheux H. Z., Voisin S., Cheng C. L., Perfect E., Horita J., Warren J. M., "Water calibration measurements for neutron radiography: application to water content quantification in porous media", Nuclear
Clean Tech San Diego | Open Energy Information
San Diego San Diego Jump to: navigation, search Name Clean Tech San Diego Address 4510 Executive Drive Place San Diego, California Zip 92121 Region Southern CA Area Notes Non-profit membership organization formed to accelerate San Diego as a world leader in the clean technology economy Website http://www.cleantechsandiego.o Coordinates 32.875965°, -117.21085° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":32.875965,"lon":-117.21085,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}
Levee Decisions and Sustainability for the Sacramento-San Joaquin Delta
Levee decisions and sustainability for the Sacramento-SanLevee Decisions and Sustainability for the Sacramento-San
Suddeth, Robyn J; Mount, Jeff; Lund, Jay R
This patent relates to neutronic reactors of the heterogeneous water cooled type, and in particular to a fuel element charging and discharging means therefor. In the embodiment illustrated the reactor contains horizontal, parallel coolant tubes in which the fuel elements are disposed. A loading cart containing a magnzine for holding a plurality of fuel elements operates along the face of the reactor at the inlet ends of the coolant tubes. The loading cart is equipped with a ram device for feeding fuel elements from the magazine through the inlot ends of the coolant tubes. Operating along the face adjacent the discharge ends of the tubes there is provided another cart means adapted to receive irradiated fuel elements as they are forced out of the discharge ends of the coolant tubes by the incoming new fuel elements. This cart is equipped with a tank coataining a coolant, such as water, into which the fuel elements fall, and a hydraulically operated plunger to hold the end of the fuel element being discharged. This inveation provides an apparatus whereby the fuel elements may be loaded into the reactor, irradiated therein, and unloaded from the reactor without stopping the fiow of the coolant and without danger to the operating personnel.
Ohlinger, L.A.; Wigner, E.P.; Weinberg, A.M.; Young, G.J.
Neutron streak camera
Apparatus for improved sensitivity and time resolution of a neutron measurement. The detector is provided with an electrode assembly having a neutron sensitive cathode which emits relatively low energy secondary electrons. The neutron sensitive cathode has a large surface area which provides increased sensitivity by intercepting a greater number of neutrons. The cathode is also curved to compensate for differences in transit time of the neutrons emanating from the point source. The slower speeds of the secondary electrons emitted from a certain portion of the cathode are matched to the transit times of the neutrons impinging thereupon.
Wang, C.L.
Organic metal neutron detector
A device for detection of neutrons comprises: as an active neutron sensing element, a conductive organic polymer having an electrical conductivity and a cross-section for said neutrons whereby a detectable change in said conductivity is caused by impingement of said neutrons on the conductive organic polymer which is responsive to a property of said polymer which is altered by impingement of said neutrons on the polymer; and means for associating a change in said alterable property with the presence of neutrons at the location of said device.
Butler, M.A.; Ginley, D.S.
Layered semiconductor neutron detectors
Room temperature operating solid state hand held neutron detectors integrate one or more relatively thin layers of a high neutron interaction cross-section element or materials with semiconductor detectors. The high neutron interaction cross-section element (e.g., Gd, B or Li) or materials comprising at least one high neutron interaction cross-section element can be in the form of unstructured layers or micro- or nano-structured arrays. Such architecture provides high efficiency neutron detector devices by capturing substantially more carriers produced from high energy .alpha.-particles or .gamma.-photons generated by neutron interaction.
Mao, Samuel S; Perry, Dale L
MATERIALS FOR SPALLATION NEUTRON SOURCES: IV: Neutronics
The Department of Energy has initiated a pre-conceptual design study for the National Spallation Neutron Source (NSNS) and given preliminary approval for the�...
2009 National Electric Transmission Congestion Study - San Francisco
San San Francisco Workshop 2009 National Electric Transmission Congestion Study - San Francisco Workshop On June 11, 2008, DOE hosted a regional pre-study workshop in San Francisco, CA to receive input and suggestions concerning the 2009 National Electric Transmission Congestion Study. The agenda, full transcript, and documents submitted for consideration for the 2009 study are available below. 6-11-08 Congestion Workshop Agenda - San Francisco, CA.pdf Transcript - 2009 National Electric Transmission Congestion Study San Francisco Workshop.pdf California Initiatives To Be Considered in DOE's 2009 Congestion Study, submitted at 2009 Congestion Study San Francisco workshop.pdf Arizona Renewable Transmission Task Force BTA Response, submitted at 2009 Congestion Study San Francisco workshop.pdf
Energy Efficiency Takes Root at the Presidio of San Francisco
5 Energy Efficiency Takes Root at the Presidio of San Francisco The Presidio from the Golden Gate Bridge The Presidio of San Francisco, recently turned over to the National Park...
New San Antonio Airport Terminal Generating Clean Power | Department of
San Antonio Airport Terminal Generating Clean Power San Antonio Airport Terminal Generating Clean Power New San Antonio Airport Terminal Generating Clean Power January 27, 2011 - 2:03pm Addthis The new photovoltaic system at the San Antonio International Airport. The new photovoltaic system at the San Antonio International Airport. Todd G. Allen Project Officer, Golden Field Office What are the key facts? The City of San Antonio's EECBG proram staff awarded a block grant for a solar photovoltaic (PV) system at the airport, designed and built the project, and complied with all local and federal regulations... all in seven months. In early 2010, the City of San Antonio's Energy Efficiency and Conservation Block Grant (EECBG) program staff quickly realized a golden opportunity lay right at their fingertips. The opening of the new San
Alternative Fuels Data Center: Students Reduce Vehicle Idling in San
Students Reduce Students Reduce Vehicle Idling in San Antonio, Texas to someone by E-mail Share Alternative Fuels Data Center: Students Reduce Vehicle Idling in San Antonio, Texas on Facebook Tweet about Alternative Fuels Data Center: Students Reduce Vehicle Idling in San Antonio, Texas on Twitter Bookmark Alternative Fuels Data Center: Students Reduce Vehicle Idling in San Antonio, Texas on Google Bookmark Alternative Fuels Data Center: Students Reduce Vehicle Idling in San Antonio, Texas on Delicious Rank Alternative Fuels Data Center: Students Reduce Vehicle Idling in San Antonio, Texas on Digg Find More places to share Alternative Fuels Data Center: Students Reduce Vehicle Idling in San Antonio, Texas on AddThis.com... March 25, 2010 Students Reduce Vehicle Idling in San Antonio, Texas
Vehicle Technologies Office: Workplace Charging Challenge Partner: San
San Diego Gas and Electric to someone by E-mail San Diego Gas and Electric to someone by E-mail Share Vehicle Technologies Office: Workplace Charging Challenge Partner: San Diego Gas and Electric on Facebook Tweet about Vehicle Technologies Office: Workplace Charging Challenge Partner: San Diego Gas and Electric on Twitter Bookmark Vehicle Technologies Office: Workplace Charging Challenge Partner: San Diego Gas and Electric on Google Bookmark Vehicle Technologies Office: Workplace Charging Challenge Partner: San Diego Gas and Electric on Delicious Rank Vehicle Technologies Office: Workplace Charging Challenge Partner: San Diego Gas and Electric on Digg Find More places to share Vehicle Technologies Office: Workplace Charging Challenge Partner: San Diego Gas and Electric on AddThis.com... Goals Research & Development
Solar San Jose | Open Energy Information
San Jose San Jose Place San Jose, California Zip 95112 Region Bay Area Website http://www.solarsanjose.com/ Coordinates 37.3456227°, -121.8847222° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":37.3456227,"lon":-121.8847222,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}
San Marcos Biomass Facility | Open Energy Information
Marcos Biomass Facility Marcos Biomass Facility Jump to: navigation, search Name San Marcos Biomass Facility Facility San Marcos Sector Biomass Facility Type Landfill Gas Location San Diego County, California Coordinates 33.0933809°, -116.6081653° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":33.0933809,"lon":-116.6081653,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}
San Gorgonio Farms | Open Energy Information
San Gorgonio Farms San Gorgonio Farms Jump to: navigation, search Name San Gorgonio Farms Place Torrance, California Zip CA 90503 Sector Wind energy Product California-based wind project developer. Coordinates 40.417285°, -79.223959° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":40.417285,"lon":-79.223959,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}
Clean Cities: San Francisco Clean Cities coalition
Francisco Clean Cities Coalition Francisco Clean Cities Coalition The San Francisco Clean Cities coalition works with vehicle fleets, fuel providers, community leaders, and other stakeholders to reduce petroleum use in transportation. San Francisco Clean Cities coalition Contact Information Bill Zeller 415-355-3728 email@example.com Coalition Website Clean Cities Coordinator Bill Zeller Photo of Bill Zeller Bill Zeller currently leads the San Francisco Clean Cities Coalition. Although he is new to the leadership position, he has worked with SFCCC for many years as an active stakeholder representing PG&E and as the Treasurer. He has worked in the clean transportation industry since the late 1980s, promoting natural gas and electric vehicles. He recently retired from PG&E after 28 years of service. He is now the manager of Clean Vehicle Programs
San Onofre nuclear outage contributes to Southern California�s ...
Short, timely articles with graphics on energy, facts, issues ... in the Southern California Edison and San ... company providing retail ...
Facilities | ORNL Neutron Sciences
Isotope Reactor. The pulsed neutron source at SNS and the continuous neutron source at HFIR complement each other well and, along with their state-of-the-art instruments, provide...
Ultrafast neutron detector
A neutron detector of very high temporal resolution is described. It may be used to measure distributions of neutrons produced by fusion reactions that persist for times as short as about 50 picoseconds.
Opportunities for Neutrino Physics at the Spallation Neutron Source (SNS)
In this paper we discuss opportunities for a neutrino program at the Spallation Neutrons Source (SNS) being commissioning at ORNL. Possible investigations can include study of neutrino-nuclear cross sections in the energy rage important for supernova dynamics and neutrino nucleosynthesis, search for neutrino-nucleus coherent scattering, and various tests of the standard model of electro-weak interactions.
Yu Efremenko; W R Hix
Arsenic activation neutron detector
A detector of bursts of neutrons from a deuterium-deuteron reaction includes a quantity of arsenic adjacent a gamma detector such as a scintillator and photomultiplier tube. The arsenic is activated by the 2.5-MeV neutrons to release gamma radiation which is detected to give a quantitative representation of detected neutrons.
Jacobs, E.L.
Advanced neutron absorber materials
A neutron absorbing material and method utilizing rare earth elements such as gadolinium, europium and samarium to form metallic glasses and/or noble base nano/microcrystalline materials, the neutron absorbing material having a combination of superior neutron capture cross sections coupled with enhanced resistance to corrosion, oxidation and leaching.
Branagan, Daniel J. (Idaho Falls, ID); Smolik, Galen R. (Idaho Falls, ID)
San Diego, Texas -- Plazas of San Diego Texas: Signatures of Mexican-American Place Identity
1989). Moreover, most South Texas towns stage these and1978). 4. Some other South Texas Mexican- American townsPlazas of San Diego Texas: S i g n a t u r e s of Mexican-
Arreola, Daniel D
POLARIZATION OF Li$sup 7$(p,n)Be$sup 7$ NEUTRONS
The polarization of neutrons emitted from the Li/sup 7/(p,n)Be/sup 7/ reaction at an angle of 50 deg was measured for neutron energies between 0.7 and 1.5 Mev. The polarization was deduced from the right-left asymmetry in the scattering of these neutrons from liquid oxygen. The results indicate that the polarization is close to --0.3, independent of hombarding energy. One measurement for neutrons emitted at 30 deg yields a polarization only slightly smaller than for neutrons emitted at 50 deg for the same proton energy. The total neutron cross section of oxygen was remeasured for neutron energies between 0.7 and 1.4 Mev. (auth)
Striebel, H.R.; Darden, S.E.; Haeberli, W.
Characteristics of the Neutron Irradiation Facilities of the PSI Calibration Laboratory
The neutron radiation fields of the Calibration Laboratory at Paul Scherrer Institute (PSI) are traceable to the national standards of the Physikalisch-Technische Bundesanstalt (PTB) in Germany. A Berthold LB6411 neutron dose rate meter for neutron radiation is used as a secondary standard. Recently, a thorough characterization of the neutron irradiation fields of the {sup 241}Am-Be and {sup 252}Cf sources by means of reference measurements and a detailed MCNPX simulation of the irradiation facility has been initiated. In this work, the characteristics of the neutron radiation fields are summarized and presented together with model equations and an uncertainty analysis. MCNPX results are shown for the {sup 241}Am-Be source. A comparison of measured and simulated data shows an excellent agreement. From the simulation, valuable information about the neutron fields like the contribution of scattered neutrons in the fields and the energy spectra could be obtained.
Hoedlmoser, H.; Schuler, Ch.; Butterweck, G.; Mayer, S. [Paul Scherrer Institut, 5232 Villigen PSI (Switzerland)
San Jose, California: Solar in Action (Brochure)
This brochure provides an overview of the challenges and successes of San Jose, CA, a 2008 Solar America City awardee, on the path toward becoming a solar-powered community. Accomplishments, case studies, key lessons learned, and local resource information are given.
San Francisco, California: Solar in Action (Brochure)
This brochure provides an overview of the challenges and successes of San Francisco, CA, a 2007 Solar America City awardee, on the path toward becoming a solar-powered community. Accomplishments, case studies, key lessons learned, and local resource information are given.
San Antonio, Texas: Solar in Action (Brochure)
This brochure provides an overview of the challenges and successes of San Antonio, TX, a 2008 Solar America City awardee, on the path toward becoming a solar-powered community. Accomplishments, case studies, key lessons learned, and local resource information are given.
Temperature Trends at San Juan, Puerto Rico
Observations at the San Juan, Puerto Rico international airport show that the annual mean temperature has increased by about 2.1�C (3.8�F) from 1956 to 1983. The chief contributors to the increase are an increase in daily minimum temperature from ...
Claude E. Duchon
San Bernardino Los AngelesVentura
Power Project Solar Power Plant Licensing Projects T:\\Pr ojects \\CEC\\CE C P rojec ts \\Current CE C Beacon Solar, LLC Ridgecrest Solar Power Project 250 MW - Kern Co. Solar Millennium, LLC Hidden HillsSource Energy, Inc. Calico Solar Project 100.5 MW (Solar Thermal) San Bernardino Co. Approved October 28, 2010
Beacon Solar Energy Project 250 MW - Kern Co. Approved August 25, 2010 Beacon Solar, LLC Ridgecrest SolarSource Energy, INC Rio Mesa Solar 750 MW - Riverside Co. BrightSource Energy, INC Genesis Solar Energy Project MW - San Bernardino Co. Approved September 8, 2010 Mojave Solar, LLC Rice Solar Energy Project 150 MW
San Diego, California: Solar in Action (Brochure)
This brochure provides an overview of the challenges and successes of San Diego, CA, a 2007 Solar America City awardee, on the path toward becoming a solar-powered community. Accomplishments, case studies, key lessons learned, and local resource information are given.
City of San Francisco - Commercial Efficiency Rebates | Department of
San Francisco - Commercial Efficiency Rebates San Francisco - Commercial Efficiency Rebates City of San Francisco - Commercial Efficiency Rebates < Back Eligibility Commercial Multi-Family Residential Savings Category Heating & Cooling Commercial Heating & Cooling Heating Home Weatherization Construction Commercial Weatherization Design & Remodeling Manufacturing Other Appliances & Electronics Commercial Lighting Lighting Water Heating Program Info State California Program Type Local Rebate Program Businesses in San Francisco's PG&E territory can receive equipment rebates, a detailed energy analysis, and the discounted installation of a variety of energy efficiency technologies through San Francisco's Energy Watch Program. A range of incentives are available for lighting, HVAC, food service equipment and network power management systems. See web site above
City of San Diego - Sustainable Building Policy | Department of Energy
San Diego - Sustainable Building Policy San Diego - Sustainable Building Policy City of San Diego - Sustainable Building Policy < Back Eligibility Commercial Construction Local Government Residential Savings Category Heating & Cooling Commercial Heating & Cooling Cooling Home Weatherization Construction Commercial Weatherization Design & Remodeling Appliances & Electronics Heat Pumps Commercial Lighting Lighting Water Heating Bioenergy Solar Windows, Doors, & Skylights Alternative Fuel Vehicles Hydrogen & Fuel Cells Buying & Making Electricity Water Heating Wind Program Info State California Program Type Energy Standards for Public Buildings Provider San Diego Environmental Services Department The City of San Diego's Sustainable Building Policy is directed by Council Policy 900-14. The policy contains regulations regarding building
San Bernardino County - Green Building Incentive | Department of Energy
You are here You are here Home » San Bernardino County - Green Building Incentive San Bernardino County - Green Building Incentive < Back Eligibility Commercial Construction Installer/Contractor Residential Savings Category Heating & Cooling Commercial Heating & Cooling Cooling Heating Heat Pumps Appliances & Electronics Water Heating Bioenergy Home Weatherization Commercial Weatherization Solar Lighting Windows, Doors, & Skylights Buying & Making Electricity Water Wind Program Info State California Program Type Green Building Incentive San Bernardino's Board of Supervisors launched Green County San Bernardino in August 2007. The program includes a number of incentives to encourage residents, builders, and businesses to adopt more sustainable practices. Builders who participate in San Bernardino County's
San Isabel Electric Association - Residential Energy Efficiency Rebate
San Isabel Electric Association - Residential Energy Efficiency San Isabel Electric Association - Residential Energy Efficiency Rebate Program San Isabel Electric Association - Residential Energy Efficiency Rebate Program < Back Eligibility Residential Savings Category Appliances & Electronics Water Heating Program Info State Colorado Program Type Utility Rebate Program Rebate Amount Marathon Water Heaters: $175 Marathon Water Heaters w/ SIEA Load Control Program: $425 Electric Water Heater (minimum 30 gallon): $100 Washers: $80 Dryer w/ Moisture Sensor: $50 Dishwashers: $60 Refrigerators: $90 Freezers: $90 ETS Room Units: $72 - $180 ETS Furnaces: $432 - $768 Provider San Isabel Electric Association San Isabel Electric Association (SIEA) provides incentives for its residential customers to install energy efficient equipment. Rebates are
BASIS Equipment | ORNL Neutron Sciences
Equipment Equipment BASIS Schematic Schematic of the SNS Backscattering Spectrometer. Helium dewer cooling a sample Helium dewer cooling a sample (bird's eye view). The heart of the work in a typical experiment is setting up the sample in the desired environment. A typical neutron sample ranging from a millimeter to a few centimeters is placed in a specialized cylindrical can and sealed. For liquids, the backscattering instrument often uses an annular can, created by placing a smaller can within a larger can and inserting the liquid sample between the two cans. This picture shows a helium dewer cooling the environment encompassing the sample can, which has been lowered into the beam from the top of the scattering tank. Crystals Crystals. The backscattering spectrometer is defined by the reflection of specific
Materials Highlights | Neutron Science | ORNL
Materials Materials SHARE Materials Highlights 1-7 of 7 Results Neutron scattering characterizes dynamics in polymer family December 01, 2012 - Understanding the interplay between structure and dynamics is the key to obtaining tailor-made materials. In the last few years, a large effort has been devoted to characterizing and relating the structure and dynamic properties in families of polymers with alkyl side groups. Theory meets experiment: structure-property relationships in an electrode material for solid-oxide fuel cells December 01, 2012 - Fuel cell technology is one potentially very efficient and environmentally friendly way to convert the chemical energy of fuels into electricity. Solid-oxide fuel cells (SOFCs) can convert a wide variety of fuels with simpler, cheaper designs than those used in
Scientific Labs | Neutron Science | ORNL
Scientific Labs Scientific Labs SHARE SNS Scientific Labs Meilleur-lab-students-300.jpg Students in the SNS chemistry lab practice pipetting water. A new complex of laboratories is now open at SNS, providing a flexible, mobile environment where users can work efficiently. The labs, on the second floor of the SNS Central Laboratory and Office Building, are built with "green" operations in mind, as well as to optimize the available space for researchers' ever-changing scientific needs. With overhead utilities and mobile furniture, the complex's 13 labs allow staff to easily reconfigure the layout of equipment and quickly change an experiment's setup as needed. "We surveyed more than 900 users on what they needed, and they gave us a wish list," says Chrissi Schnell, the Neutron Scattering Science Division
Neutron skin uncertainties of Skyrme energy density functionals
Background: Neutron-skin thickness is an excellent indicator of isovector properties of atomic nuclei. As such, it correlates strongly with observables in finite nuclei that depend on neutron-to-proton imbalance and the nuclear symmetry energy that characterizes the equation of state of neutron-rich matter. A rich worldwide experimental program involving studies with rare isotopes, parity violating electron scattering, and astronomical observations is devoted to pinning down the isovector sector of nuclear models. Purpose: We assess the theoretical systematic and statistical uncertainties of neutron-skin thickness and relate them to the equation of state of nuclear matter, and in particular to nuclear symmetry energy parameters. Methods: We use the nuclear superfluid Density Functional Theory with several Skyrme energy density functionals and density dependent pairing. To evaluate statistical errors and their budget, we employ the statistical covariance technique. Results: We find that the errors on neutron skin increase with neutron excess. Statistical errors due to uncertain coupling constants of the density functional are found to be larger than systematic errors, the latter not exceeding 0.06 fm in most neutron-rich nuclei across the nuclear landscape. The single major source of uncertainty is the poorly determined slope L of the symmetry energy that parametrizes its density dependence. Conclusions: To provide essential constraints on the symmetry energy of the nuclear energy density functional, next-generation measurements of neutron skins are required to deliver precision better than 0.06 fm.
M. Kortelainen; J. Erler; W. Nazarewicz; N. Birge; Y. Gao; E. Olsen
High energy neutron dosimeter
A device for measuring dose equivalents in neutron radiation fields is described. The device includes nested symmetrical hemispheres (forming spheres) of different neutron moderating materials that allow the measurement of dose equivalents from 0.025 eV to past 1 GeV. The layers of moderating material surround a spherical neutron counter. The neutron counter is connected by an electrical cable to an electrical sensing means which interprets the signal from the neutron counter in the center of the moderating spheres. The spherical shape of the device allows for accurate measurement of dose equivalents regardless of its positioning. 2 figures.
Rai, K.S.F.
A device for measuring dose equivalents in neutron radiation fields. The device includes nested symmetrical hemispheres (forming spheres) of different neutron moderating materials that allow the measurement of dose equivalents from 0.025 eV to past 1 GeV. The layers of moderating material surround a spherical neutron counter. The neutron counter is connected by an electrical cable to an electrical sensing means which interprets the signal from the neutron counter in the center of the moderating spheres. The spherical shape of the device allows for accurate measurement of dose equivalents regardless of its positioning.
Sun, Rai Ko S.F. (Albany, CA)
City of San Diego Environmental Services Department | Open Energy
Environmental Services Department Environmental Services Department Jump to: navigation, search Name City of San Diego Environmental Services Department Place San Diego, California Zip 92123 Sector Services, Solar Product City of San Diego's environmental services department. It is a power purchaser of electricity generated by a 0.9MW solar PV array located at its Alvarado water treatment plant. References City of San Diego Environmental Services Department[1] LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! This article is a stub. You can help OpenEI by expanding it. City of San Diego Environmental Services Department is a company located in San Diego, California . References ↑ "City of San Diego Environmental Services Department" Retrieved from
Spallation Neutron Source, SNS
Spallation Neutron Source Spallation Neutron Source Providing the most intense pulsed neutron beams in the world... Accumulator Ring Commissioning Latest Step for Spallation Neutron Source The Spallation Neutron Source, located at Oak Ridge National Laboratory, has passed another milestone on the way to completion this year--the commissioning of the proton accumulator ring. Brookhaven led the design and construction of the accumulator ring, which will allow an order of magnitude more beam power than any other facility in the world. The Spallation Neutron Source (SNS) is an accelerator-based neutron source being built in Oak Ridge, Tennessee, by the U.S. Department of Energy. The figure on the right shows a schematic of the accumulator ring and transport beam lines that are being designed and built by Brookhaven
Relative measurements of the cross section for scattering of neutrons by protons have been made at 10 MeV neutron energy for center-of-mass neutron scattering angles from 60' to 180'. The measurements were made using the Ohio University Accelerator Laboratory's tandem Van de Graaff accelerator with the D(d,n) reaction as the neutron source. The data are in good agreement with predictions from the phase shift analyses of Arndt, the groups of Nijmegen and Bonn, and the ENDF/B-V evaluation. The ENDF/B-VI evaluation does not appear to have the same angular dependence as the data. KEYWORDS: hydrogen cross section, neutron cross section standard, hydrogen angular distribution standard
Boukharouba, N.; Bateman, F. B. (Fred B.); Brient, C. E.; Carlson, A. D.; Grimes, S. M.; Massey, T. N.; Haight, Robert C.; Carlson, Allan D.; Wasson, O. A.
News & Events | ORNL Neutron Sciences
2011 News 2011 News Neutron Science In the News - 2011 December November October September August July June May March February January Because some media sources archive past articles and require a subscription for access, some of the links below might not be active. If a citation listed here is no longer available, please contact the newspaper or your library directly. December SANS tracks cell death protein invading biomimetic mitochondrial membrane Physorg.com 12/15 Programmed cell death, or apoptosis, is a naturally occurring and necessary biological process. In apoptosis, the 192 amino acid BAX protein inserts itself into mitochondrial membranes, causing their contents to leak out and their eventual demise. This is our fate as mammals. In a typical human, some 50 to 70 million
Environment scattering in GADRAS.
Radiation transport calculations were performed to compute the angular tallies for scattered gamma-rays as a function of distance, height, and environment. Green's Functions were then used to encapsulate the results a reusable transformation function. The calculations represent the transport of photons throughout scattering surfaces that surround sources and detectors, such as the ground and walls. Utilization of these calculations in GADRAS (Gamma Detector Response and Analysis Software) enables accurate computation of environmental scattering for a variety of environments and source configurations. This capability, which agrees well with numerous experimental benchmark measurements, is now deployed with GADRAS Version 18.2 as the basis for the computation of scattered radiation.
Thoreson, Gregory G.; Mitchell, Dean James; Theisen, Lisa Anne; Harding, Lee T.
Imaging and Neutrons - IAN 2006 - Neutron Sciences
SNS Home Saturday, January 11, 2014 SNS Home Saturday, January 11, 2014 Go IAN 2006 Imaging and Neutrons 2006 October 23-25, 2006 Iran Thomas Auditorium Central Laboratory and Office Building Spallation Neutron Source Oak Ridge National Laboratory, Oak Ridge, TN Who Should Attend Synopsis Goals and Expected Outcomes Application Areas Techniques International Advisory Committee Local Organizing Committee Agenda with Presentations NEW Confirmed Speakers Frequently Asked Questions - FAQ Satellite Workshop - Progress in Electron Volt Neutron Spectroscopy eV Worshop Agenda presentations NEW Lodging, Transportation, Bus Schedule Location Directions and Map Registration CLOSED Abstracts, Posters, Contributed Talks Scholarships Sponsors Vendors May Attend Relevant Reports Important Dates Weather Attractions
The method and means for controlling the neutron density in a nuclear reactor is described. It describes the method and means for flattening the neutron density distribution curve across the reactor by spacing the absorbing control members to varying depths in the central region closer to the center than to the periphery of the active portion of the reactor to provide a smaller neutron reproduction ratio in the region wherein the members are inserted, than in the remainder of the reactor thereby increasing the over-all potential power output.
Young, G.J.
Coupled-Channel Evaluations of Cross Sections for Scattering Involving Particle-Unstable Resonances
How does the scattering cross section change when the colliding bound-state fragments are allowed particle-emitting resonances? This question is explored in the framework of a multichannel algebraic scattering method of determining nucleon-nucleus cross sections at low energies. Two cases are examined, the first being a gedanken investigation in which n+{sup 12}C scattering is studied with the target states assigned artificial widths. The second is a study of neutron scattering from {sup 8}Be, a nucleus that is particle unstable. Resonance character of the target states markedly varies evaluated cross sections from those obtained assuming stability in the target spectrum.
Fraser, P.; Amos, K. [School of Physics, University of Melbourne, Victoria 3010 (Australia); Canton, L.; Pisent, G. [Istituto Nazionale di Fisica Nucleare, Sezione di Padova, I-35131 (Italy); Karataglidis, S. [Department of Physics and Electronics, Rhodes University, Grahamstown 6140 (South Africa); Svenne, J. P. [Department of Physics and Astronomy, University of Manitoba, Winnipeg, Manitoba, R3T 2N2 (Canada); Knijff, D. van der [Advanced Research Computing, Information Division, University of Melbourne, Victoria 3010 (Australia)
Predictive model of nucleon-nucleus scattering cross sections
Nucleon total reaction and neutron total cross sections as well as differential (including spin) observables from 25 to 300 MeV for stable nuclei from 6Li to 238U have been predicted that are in good agreement with measured data. Those predictions have been made using non-local, energy dependent, and complex optical potentials in coordinate space formed by full folding of effective nucleon-nucleon interactions with realistic nuclear ground state densities. By inverse kinematics the same model prescription describes exotic (radioactive) nuclei scattering from hydrogen as a target and the results reveal the extended (neutron) distributions such nuclei can have.
Amos, K. (Ken); Deb, P. (Pradip); Karataglidis, S. (Steven); Madland, D. G.
Magnetic Structure Analysis from Neutron Powder Diffraction Data Using GSAS
Magnetic Structure Analysis from Neutron Powder Diffraction Data Using GSAS Magnetic Structure Analysis from Neutron Powder Diffraction Data Using GSAS This set of web pages provides reference information from the Magnetic Structure Analysis from Neutron Powder Diffraction Data Using GSAS workshop presented at the 2006 American Conference on Neutron Scattering held in St. Charles, IL, June 18-22, 2006. Workshop Schedule: 9:00-9:05 am: Introduction (B.H. Toby) 9:05-9:50 am: History, Color symmetry & Shubnikov space groups (B. Chakoumous) Lecture notes: History and Color symmetry & Shubnikov space groups 9:50-10:20 am: Magnetic extinctions classes & common magnetic structure types (R.B. Von Dreele) Lecture Notes Break 10:50-11:45 am: Overview of representational analysis & FullProf implementation (L.C. Chapon) Lecture Notes and Accompanying files