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1,300 | Suppose that you have an abstract for a scientific paper: we investigate common - noise - induced phase synchronization between uncoupled identical hele - shaw cells exhibiting oscillatory convection . using the phase description method for oscillatory convection
, we demonstrate that the uncoupled systems of oscillatory hele - shaw convection can exhibit in - phase synchronization when driven by weak common noise .
we derive the lyapunov exponent determining the relaxation time for the synchronization , and develop a method for obtaining the optimal spatial pattern of the common noise to achieve synchronization .
the theoretical results are confirmed by direct numerical simulations . .
And you have already written the first three sentences of the full article: populations of self - sustained oscillators can exhibit various synchronization phenomena @xcite .
for example , it is well known that a limit - cycle oscillator can exhibit phase locking to a periodic external forcing ; this phenomenon is called the forced synchronization @xcite .
recently , it was also found that uncoupled identical limit - cycle oscillators subject to weak common noise can exhibit in - phase synchronization ; this remarkable phenomenon is called the common - noise - induced synchronization @xcite . in general , each oscillatory dynamics is described by a stable limit - cycle solution to an ordinary differential equation , and the phase description method for ordinary limit - cycle oscillators has played an essential role in the theoretical analysis of the synchronization phenomena @xcite . on the basis of the phase description ,.
Please generate the next two sentences of the article | optimization methods for the dynamical properties of limit - cycle oscillators have also been developed for forced synchronization @xcite and common - noise - induced synchronization @xcite .
synchronization phenomena of spatiotemporal rhythms described by partial differential equations , such as reaction - diffusion equations and fluid equations , have also attracted considerable attention @xcite ( see also refs . |
1,301 | Suppose that you have an abstract for a scientific paper: based on the observation that the correlation between observed traffic at two measurement points or traffic stations may be time - varying , attributable to the time - varying speed which subsequently causes variations in the time required to travel between the two points , in this paper , we develop a modified space - time autoregressive integrated moving average ( starima ) model with time - varying lags for short - term traffic flow prediction .
particularly , the temporal lags in the modified starima change with the time - varying speed at different time of the day or equivalently change with the ( time - varying ) time required to travel between two measurement points .
firstly , a technique is developed to evaluate the temporal lag in the starima model , where the temporal lag is formulated as a function of the spatial lag ( spatial distance ) and the average speed .
secondly , an unsupervised classification algorithm based on isodata algorithm is designed to classify different time periods of the day according to the variation of the speed .
the classification helps to determine the appropriate time lag to use in the starima model .
finally , a starima - based model with time - varying lags is developed for short - term traffic prediction . experimental results using real traffic data show that the developed starima - based model with time - varying lags has superior accuracy compared with its counterpart developed using the traditional cross - correlation function and without employing time - varying lags . .
And you have already written the first three sentences of the full article: road traffic prediction plays an important role in intelligent transport systems by providing the required real - time information for traffic management and congestion control , as well as the long - term traffic trend for transport infrastructure planning @xcite .
road traffic predictions can be broadly classified into short - term traffic predictions and long - term traffic forecasts@xcite .
short - term prediction is essential for the development of efficient traffic management and control systems , while long - term prediction is mainly useful for road design and transport infrastructure planning ..
Please generate the next two sentences of the article | there are two major categories of techniques for road traffic prediction : those based on non - parametric models and those based on parametric models .
non - parametric model based techniques , such as k - nearest neighbors ( knn ) model @xcite and artificial neural networks ( ann ) @xcite , are inherently robust and valid under very weak assumptions @xcite , while parametric model based techniques , such as auto - regressive integrated moving average ( arima ) model @xcite and its variants @xcite@xcite , allows to integrate knowledge of the underlying traffic process in the form of traffic models that can then be used for traffic prediction . |
1,302 | Suppose that you have an abstract for a scientific paper: a novel type of correlation involving particle - antiparticle pairs was found out in the 1990 s .
currently known as squeezed or back - to - back correlations ( bbc ) , they should be present if the hadronic masses are modified in the hot and dense medium formed in high energy heavy ion collisions .
although well - established theoretically , such hadronic correlations have not yet been observed experimentally . in this phenomenological study
we suggest a promising way to search for the bbc signal , by looking into the squeezed correlation function of @xmath0 and @xmath1 pairs at rhic energies , as function of the pair average momentum , @xmath2 .
the effects of in - medium mass - shift on the identical particle correlations ( hanbury - brown & twiss effect ) are also discussed . .
And you have already written the first three sentences of the full article: the hadronic particle - antiparticle correlation was already pointed out in the beginning of the nineties . however , the final formulation of these hadronic squeezed or back - to - back correlations was proposed only at the end of that decade@xcite , predicting that such correlations were expected if the masses of the mesons were modified in the hot and dense medium formed in high energy nucleus - nucleus collisions . soon after that , it was shown that analogous correlations would exist in the case of baryons as well .
an interesting theoretical finding was that both the fermionic ( fbbc ) and the bosonic ( bbbc ) back - to - back correlations were very similar , both being positive and treated by analogous formalisms . in
what follows , we will focus our discussion to the bosonic case , illustrating the effect by considering @xmath0 and @xmath1 pairs , considered to be produced at rhic energies@xcite ..
Please generate the next two sentences of the article | let us discuss the case of @xmath3-mesons first , which are their own antiparticles , and suppose that their masses are modified in hot and dense medium .
naturally , they recover their asymptotic masses after the system freezes - out . |
1,303 | Suppose that you have an abstract for a scientific paper: we use restframe near- and mid - ir data of an isotropically selected sample of quasars and radio galaxies at @xmath0 , which have been published previously , to study the wavelength - dependent anisotropy of the ir emission . for
that we build average seds of the quasar subsample (= type 1 agn ) and radio galaxies (= type 2 agn ) from @xmath1 and plot the ratio of both average samples . from 2 to 8@xmath2 restframe wavelength
the ratio gradually decreases from 20 to 2 with values around 3 in the 10@xmath2 silicate feature .
longward of 12@xmath2 the ratio decreases further and shows some high degree of isotropy at 15@xmath2 ( ratio @xmath31.4 ) .
the results are consistent with upper limits derived from the x - ray / mid - ir correlation of local seyfert galaxies .
we find that the anisotropy in our high - luminosity radio - loud sample is smaller than in radio - quiet lower - luminosity agn which may be interpreted in the framework of a receding torus model with luminosity - dependent obscuration properties .
it is also shown that the relatively small degree of anisotropy is consistent with clumpy torus models . .
And you have already written the first three sentences of the full article: in the unification scheme of agn the difference between type 1 and type 2 agn is explained by angle - dependent circumnuclear obscuration of the accretion disk and broad - line region @xcite . this obscuring dusty medium
commonly referred to as `` dust torus '' is optically and geometrically thick and probably extends from sub - parsec scales outward to several 10s of parsecs , or beyond for high luminosity objects .
the dust in the torus absorbs the incident uv / optical radiation an re - emits the received energy in the infrared.
Please generate the next two sentences of the article | . observations have shown that type 1 agn show significantly more emission in the near - ir than type 2 agn for the same given intrinsic luminosity ( e.g. * ? ? ?
this is consistent with the picture where the face - on view onto the torus in type 1 agn exposes the innermost hot dust to the observer . on the other hand in type 2 agn the torus |
1,304 | Suppose that you have an abstract for a scientific paper: spontaneous symmetry breaking is an essential feature of modern science .
we demonstrate that it also plays an important role in the physics of complex plasmas .
complex plasmas can serve as a powerful tool for observing and studying discrete types of symmetry and disordering at the kinetic level that numerous many - body systems exhibit . .
And you have already written the first three sentences of the full article: in this letter we address dynamical processes in highly ordered complex plasmas associated with _ spontaneous symmetry breaking_. spontaneous symmetry breaking ( ssb ) plays a crucial role in elementary particle physics but is also very common in classical physics @xcite .
it happens whenever the system goes from a state which has a certain symmetry , e.g. rotational symmetry , into an ordered state , which does not have this symmetry anymore . in general
, this state not necessarily has to be the ground ( vacuum ) state and the transition to the new state may or may not be associated with a phase transition ..
Please generate the next two sentences of the article | for example , in the case of magnetization the spins point all in one direction ( ordered state ) whereas above the curie temperature there is no preferred direction .
another example from a mechanical system without phase transition is a vertical stick which bends under a sufficiently high force from above to one side breaking the rotational symmetry of the system without the force . |
1,305 | Suppose that you have an abstract for a scientific paper: we have a well - established standard model for cosmology and prospects for considerable additions from work in progress .
i offer a list of elements of the standard model , comments on controversies in the interpretation of the evidence in support of this model , and assessments of the directions extensions of the standard model seem to be taking .
psfig * the standard cosmological model * + + + .
And you have already written the first three sentences of the full article: in the present almost frenetic rate of advance of cosmology it is useful to be reminded that the big news this year is the establishment of evidence , by two groups ( @xcite , @xcite ) , of detection of the relativistic curvature of the redshift - magnitude relation .
the measurement was proposed in the early 1930s .
compare this to the change in the issues in particle physics since 1930 ..
Please generate the next two sentences of the article | the slow evolution of cosmology has allowed ample time for us to lose sight of which elements are reasonably well established and which have been adopted by default , for lack of more reasonable - looking alternatives .
thus i think it is appropriate to devote a good part of my assigned space to a discussion of what might be included in the standard model for cosmology . |
1,306 | Suppose that you have an abstract for a scientific paper: we compute phase diagrams for @xmath0 starblock copolymers in the strong - segregation regime as a function of volume fraction @xmath1 , including bicontinuous phases related to minimal surfaces ( g , d , and p surfaces ) as candidate structures .
we present the details of a general method to compute free energies in the strong segregation limit , and demonstrate that the gyroid g phase is the most nearly stable among the bicontinuous phases considered .
we explore some effects of conformational asymmetry on the topology of the phase diagram .
# 1*#1 * # 1 10truept * [ fig # 1 here ] * 2 .
And you have already written the first three sentences of the full article: block copolymers ( bcps ) , comprising chemically distinct polymers permanently linked together , are interesting because of the diverse array of ordered phases to which both polymer theory and experiment have been directed.@xcite the phase behavior of diblock copolymer melts is a competition between the entropic tendency to mix the two species into an isotropic melt , and an energetic penalty for having unlike species adjacent , which induces transitions into ordered phases of many symmetries , depending on the topology and composition of the polymers . near the order - disorder transition ( weak incompatibility ) entropy effects dominate , and the individual polymers retain ( within mean field ) their gaussian coil conformation through the transition,@xcite , while at much higher incompatibilities the chains are strongly stretched .
it is this strongly stretched regime which we address here .
leibler developed the first complete theory of ordered phases in bcp melts@xcite , and predicted the by - now classical phases of lamellar ( l ) , cylindrical ( c ) and spherical ( s ) symmetry using the random phase approximation to derive an effective landau free energy in terms of composition modulations in fourier space ..
Please generate the next two sentences of the article | the strong segregation regime was studied by helfand and co - workers @xcite and semenov @xcite , who predicted the same series of phases with increasing asymmetry , denoted by the fraction @xmath1 of polymer a in an @xmath2 diblock .
( in this work we always use a to denote the minority block ) . |
1,307 | Suppose that you have an abstract for a scientific paper: we consider neutrino mixing and oscillations in presence of an arbitrary constant magnetic field with nonzero transversal @xmath0 and longitudinal @xmath1 components with respect to the direction of neutrino propagation .
the electromagnetic interaction of neutrinos is determined by diagonal and transition neutrino magnetic moments that are introduced for the neutrino mass states .
explicit expressions for the effective neutrino diagonal and transition magnetic moments for the flavor basis in terms of these values for the mass states are obtained .
the effective evolution hamiltonian for the flavor neutrino and the corresponding oscillation probability are derived .
the role of the longitudinal magnetic field component is examined . in particular
, it is shown that : 1 ) @xmath1 coupled to the corresponding magnetic moments shifts the neutrino energy , and 2 ) in case of nonvanishing neutrino transition magnetic moments @xmath1 produces an additional mixing between neutrino states , both in the mass and flavor neutrino bases . .
And you have already written the first three sentences of the full article: the nobel prize in physics awarded in 2015 to takaaki kajita and arthur mcdonald for studies of the atmospheric and solar neutrinos @xcite does not leave any doubt that neutrinos oscillate and have nonzero masses .
the latter fact leads to the well - known possibility for neutrino to have non - trivial electromagnetic properties @xcite , which brought forth the research area that was investigated in details by numerous authors ( see recent review @xcite and references therein ) .
in the course of these studies many phenomena that may appear in electromagnetic fields have been recognized and described thoroughly . among them.
Please generate the next two sentences of the article | the neutrino spin - flavor oscillations is the one , featuring both the above mentioned basic neutrino aspects nonzero mass and electromagnetic properties from the one side and mixing from another @xcite . owing to this , in spite of being a longstanding problem
, the spin - flavor oscillations can reveal some new aspects of existence of neutrino mass and electromagnetic properties . |
1,308 | Suppose that you have an abstract for a scientific paper: myriad experiments have identified an important role for @xmath0 t cell response mechanisms in determining recovery from influenza a virus infection .
animal models of influenza infection further implicate multiple elements of the immune response in defining the dynamical characteristics of viral infection . to date , influenza virus models , while capturing particular aspects of the natural infection history , have been unable to reproduce the full gamut of observed viral kinetic behaviour in a single coherent framework . here , we introduce a mathematical model of influenza viral dynamics incorporating all major immune components ( innate , humoral and cellular ) and explore its properties with a particular emphasis on the role of cellular immunity . calibrated against a range of murine data ,
our model is capable of recapitulating observed viral kinetics from a multitude of experiments .
importantly , the model predicts a robust exponential relationship between the level of effector @xmath0 t cells and recovery time , whereby recovery time rapidly decreases to a fixed minimum recovery time with an increasing level of effector @xmath0 t cells .
we find support for this relationship in recent clinical data from influenza a(h7n9 ) hospitalised patients .
the exponential relationship implies that people with a lower level of naive @xmath0 t cells may receive significantly more benefit from induction of additional effector @xmath0 t cells arising from immunological memory , itself established through either previous viral infection or t cell - based vaccines . .
And you have already written the first three sentences of the full article: invasion of influenza virus into a host s upper respiratory tract leads to infection of healthy epithelial cells and subsequent production of progeny virions @xcite .
infection also triggers a variety of immune responses . in the early stage of infection a temporary non - specific response ( innate immunity ) contributes to the rapid control of viral growth while in the late stage of infection , the adaptive immune response dominates viral clearance @xcite .
the early immune response involves production of antiviral cytokines and cells , e.g. type 1 interferon ( ifn ) and natural killer cells ( nk cells ) , and is independent of virus type @xcite . in the special case of a first infection in a naive host ,.
Please generate the next two sentences of the article | the adaptive immune response , mediated by the differentiation of naive t cells and b cells and subsequent production of virus - specific t cells and antibodies @xcite , leads to not only a prolonged killing of infected cells and virus but also the formation of memory cells which can generate a rapid immune response to secondary infection with the same virus @xcite .
@xmath0 t cells , which form a major component of adaptive immunity , play an important role in efficient viral clearance @xcite . |
1,309 | Suppose that you have an abstract for a scientific paper: we consider the security of practical continuous - variable quantum key distribution implementation with the local oscillator ( lo ) fluctuating in time , which opens a loophole for eve to intercept the secret key .
we show that eve can simulate this fluctuation to hide her gaussian collective attack by reducing the intensity of the lo .
numerical simulations demonstrate that , if bob does not monitor the lo intensity and does not scale his measurements with the instantaneous intensity values of lo , the secret key rate will be compromised severely . .
And you have already written the first three sentences of the full article: continuous - variable quantum - key distribution ( cvqkd ) , as an unconditionally secure communication scheme between two legitimate parties alice and bob , has achieved advanced improvements in theoretical analysis and experimental implementation in recent years @xcite .
practical implementation systems , such as fiber - based gaussian - modulated @xcite and discrete - modulated @xcite coherent - state protocol qkd systems over tens of kilometers , have been demonstrated in a few groups .
the unconditional security of such systems with prepare - and - measure ( pm ) implementation has been confirmed by the security analysis of the equivalent entanglement - based ( eb ) scheme @xcite ..
Please generate the next two sentences of the article | however , the traditional security analysis of the eb scheme of cvqkd just includes the signal beam and not the local oscillator ( lo ) , which is an auxiliary light beam used as a reference to define the phase of the signal state and is necessary for balanced homodyne detection .
this will leave some security loopholes for eve because lo is also unfortunately within eve s manipulating domain . |
1,310 | Suppose that you have an abstract for a scientific paper: an overview is presented of transverse momentum distributions of particles at the lhc using the tsallis distribution .
the use of a thermodynamically consistent form of this distribution leads to an excellent description of charged and identified particles .
the values of the tsallis parameter @xmath0 are truly remarkably consistent .
= by -1 .
And you have already written the first three sentences of the full article: it is by now standard to parameterize transverse momentum distributions with functions having a power law behaviour at high momenta .
this has been done by the star @xcite and phenix @xcite collaborations at rhic and by the alice @xcite , atlas @xcite and cms @xcite collaborations at the lhc . in this talk
we would like to pursue the use of the tsallis distribution to describe transverse momentum distributions at the highest beam energies ..
Please generate the next two sentences of the article | + in the framework of tsallis statistics @xcite the entropy @xmath1 , the particle number , @xmath2 , the energy density @xmath3 and the pressure @xmath4 are given by corresponding integrals over the tsallis distribution : @xmath5^{-\frac{1}{q-1 } } .\label{tsallis}\ ] ] it can be shown ( see e.g. @xcite ) that the relevant thermodynamic quantities are given by : @xmath6 , \label{entropy } \\ n & = & gv\int\frac{d^3p}{(2\pi)^3 } f^q , \label{number } \\
\epsilon & = & g\int\frac{d^3p}{(2\pi)^3}e f^q , \label{epsilon}\\ p & = & g\int\frac{d^3p}{(2\pi)^3}\frac{p^2}{3e } f^q\label{pressure } .\end{aligned}\ ] ] where @xmath7 and @xmath8 are the temperature and the chemical potential , @xmath9 is the volume and @xmath10 is the degeneracy factor . |
1,311 | Suppose that you have an abstract for a scientific paper: the powder alignment method is used to investigate the anisotropic physical properties of the weak - ferromagnetic superconductor system rusr@xmath0rcu@xmath0o@xmath1 ( r = pr , nd , sm , eu , gd , gd@xmath2dy@xmath2 ) . the rusr@xmath0gdcu@xmath0o@xmath1 ru-1212 cuprate is a weak - ferromagnetic superconductor with a magnetic ordering of ru moments at t@xmath3(ru ) = 131 k , a superconducting transition in the cuo@xmath0 layers at t@xmath4 = 56 k , and a low temperature gd antiferromagnetic ordering at t@xmath3(gd ) = 2.5 k. due to weak magnetic anisotropy of this tetragonal system , highly @xmath5-axis aligned microcrystalline powder ( diameter @xmath6 1 - 10 @xmath7 m ) in epoxy can be obtained only for r = eu and gd through the field - rotation powder alignment method where @xmath5-axis is perpendicular to the aligned magnetic field b@xmath8 = 0.9 t and parallel to the rotation axis . for smaller rare
earth compound r = gd@xmath2dy@xmath2 , powder alignment can be achieved using the simple field powder alignment method where @xmath5-axis is partially aligned along the aligned magnetic field .
no powder alignment can be achieved for larger rare earths r = pr , nd or sm due to the lack of magnetic anisotropy in these compounds .
the anisotropic temperature dependence of magnetic susceptibility for the @xmath5-axis aligned powders exhibit weak anisotropy with @xmath9 at room temperature due to anisotropic rare earth , eu and gd , contribution and crossover to @xmath10 below 190 k where strong ru anisotropic short - range exchange interaction overtakes the rare earth contribution .
anisotropic diamagnetic superconducting intragrain shielding signal of aligned microcrystalline rusr@xmath0gdcu@xmath0o@xmath1 powder - in - epoxy below vortex lattice melting temperature at 39 k in 1-g field is much weaker than the intergrain polycrystalline bulk sample signal due to the small grain size ( d @xmath6 1 - 10 @xmath7 m ) , long penetration depth ( @xmath11 0.55 @xmath7 m , @xmath12 0.66 @xmath7 m ) and the....
And you have already written the first three sentences of the full article: magnetic superconductivity has attracted much research attention since it was reported in the strongly - correlated rusr@xmath13rcu@xmath13o@xmath14 ru-1212 cuprate system ( r = sm , eu , gd , y ) with the tetragonal space group p4/mbm .
@xcite the ru magnetic moments order weak - ferromagnetically ( wfm ) with ordering temperature t@xmath15 130 k. high - t@xmath16 superconductivity occurs in the quasi-2d cuo@xmath13 bi - layers from doped holes with maximum superconducting transition onset t@xmath16(onset ) @xmath6 60 k for r = gd and coexists with the wfm order . a crossover from anisotropic 2d - like to less - anisotropic 3d - like structure
was observed near r = sm , along with a metal - insulator transition ..
Please generate the next two sentences of the article | no superconductivity can be detected for the mott insulators r = pr and nd .
since the oxygen content for all samples is close to eight after oxygen annealing , the variation of t@xmath16 with rare - earth ions indicates a self - doping of electrons from cuo@xmath13 layers to ruo@xmath17 layers . |
1,312 | Suppose that you have an abstract for a scientific paper: we present continuum high resolution submillimeter array ( sma ) observations of the transition disk object rxj1633.9 - 2442 , which is located in the ophiuchus molecular cloud and has recently been identified as a likely site of ongoing giant planet formation .
the observations were taken at 340 ghz ( 880 @xmath0 m ) with the sma in its most extended configuration , resulting in an angular resolution of 0.3@xmath1 ( 35 au at the distance of the target ) .
we find that the disk is highly inclined ( _ i _
@xmath2 50 deg ) and has an inner cavity @xmath225 au in radius , which is clearly resolved by our observations .
we simultaneously model the entire optical to millimeter wavelength spectral energy distribution ( sed ) and sma visibilities of rxj1633.9 - 2442 in order to constrain the structure of its disk .
we find that an empty cavity @xmath225 au in radius is inconsistent with the excess emission observed at 12 , 22 , and 24 @xmath0 m . instead
, the mid - ir excess can be modeled by either a narrow , optically thick ring at @xmath210 au or an optically thin region extending from @xmath27 au to @xmath225 au .
the inner disk ( r @xmath3 5 au ) is mostly depleted of small dust grains as attested by the lack of detectable near - ir excess .
we also present deep keck aperture masking observations in the near - ir , which rule out the presence of a companion up to 500 times fainter than the primary star ( in @xmath4-band ) for projected separations in the 5 - 20 au range .
we argue that the complex structure of the rxj1633.9 - 2442 disk is best explained by _ multiple _
planets embedded within the disk .
we also suggest that the properties and incidence of objects such as rxj1633.9 - 2442 , t cha , and lkca 15 ( and those of the companions recently identified to these two latter objects ) are most consistent with the runaway gas accretion phase of the core accretion model , when giant planets gain their envelopes and suddenly become massive enough to open wide gaps in the disk . .
And you have already written the first three sentences of the full article: observations of nearby star - forming regions show that the vast majority of pre - main - sequence ( pms ) stars are either accreting classical t tauri stars ( cttss ) with optically thick inner disks extending inward to the dust sublimation radius and showing a narrow range of infrared ( ir ) colors or , more evolved , non - accreting weak - line t tauri stars ( wttss ) with bare stellar photospheres . the few
transition objects " that are caught between the typical cttss and wttss stages present very diverse ir seds associated with a wide range of disk structures , but they usually have little or no excess at near - ir wavelength and much larger excesses at longer wavelengths ( see williams & cieza , 2011 for a recent review ) . ever since they were discovered by the _ infrared astronomical satellite _
( strom et al . 1989 ; wolk & walter 1996 ) , the deficit of near - infrared excess in transition disks has been interpreted as a diagnostic of inner disk clearing , possibly connected to planet formation ..
Please generate the next two sentences of the article | however , in addition to planet formation , at least three other disk evolution processes can produce the inner opacity holes that are characteristic of transition objects : grain growth , photoevaporation , and dynamical interactions with ( sub)stellar companions .
the four different mechanisms potentially responsible for the holes in transition disks might become distinguishable when , in addition to seds , disk masses , accretion rates and multiplicity information are available ( najita et al . 2007 ) . in our recent multi - wavelength study of ophiuchus transition disks ( cieza et al . |
1,313 | Suppose that you have an abstract for a scientific paper: in this work we define and study the relations between lorentzian manifolds given by the diffeomorphisms which map causal future directed vectors onto causal future directed vectors . this class of diffeomorphisms , called _ proper causal relations _ , contains as a subset the well - known group of conformal relations and are deeply linked to the so - called causal tensors of ref.@xcite .
if two given lorentzian manifolds are in _ mutual _ proper causal relation then they are said to be causally isomorphic : they are indistinguishable from the causal point of view .
finally , the concept of causal transformation for lorentzian manifolds is introduced and its main mathematical properties briefly investigated .
alfonso garca - parrado and jos m. m. senovilla 0.5 cm _ departamento de fsica terica .
universidad del pas vasco .
+ apartado 644 , 48080 bilbao , spain _ .
And you have already written the first three sentences of the full article: in this section the definitions of the basic concepts and the notation to be used throughout this contribution shall be presented .
differentiable manifolds are denoted by italic capital letters @xmath0 and , to our purposes , all such manifolds will be connected causally orientable lorentzian manifolds of dimension @xmath1 .
the signature convention is set to @xmath2 ..
Please generate the next two sentences of the article | @xmath3 and @xmath4 will stand respectively for the tangent and cotangent spaces at @xmath5 , and @xmath6 ( resp .
@xmath7 ) is the tangent bundle ( cotangent bundle ) of @xmath8 . |
1,314 | Suppose that you have an abstract for a scientific paper: spin chains have been proposed as a reliable and convenient way of transferring information and entanglement in a quantum computational context .
nonetheless , it has to be expected that any physical implementation of these systems will be subject to several perturbative factors which could potentially diminish the transfer quality . in this paper , we investigate a number of possible fabrication defects in the spin chains themselves as well as the effect of non - synchronous or imperfect input operations , with a focus on the case of multiple excitation / qubit transfer .
we consider both entangled and unentangled states , and in particular the transfer of an entangled pair of adjacent spins at one end of a chain under the mirroring rule and also the creation of entanglement resulting from injection at both end spins . .
And you have already written the first three sentences of the full article: a crucial ingredient in quantum information processing based on solid state systems is the transfer of quantum information . assuming that there are quantum registers for computing and storing information , the ability to transfer this information reliably and efficiently from one register to another is vital for the construction of larger , distributed and networked systems .
a solution to this challenge has been proposed through the use of spin chains @xcite .
the mathematical framework underpinning spin chains can be applied to various physical devices ; these could be made of any components whose states can be mapped onto spin @xmath0 particles interacting with their neighbors ..
Please generate the next two sentences of the article | electrons or excitons trapped in nanostructures form explicit examples @xcite , as do nanometer scale magnetic particles @xcite or a string of fullerenes @xcite .
another representation is the encoding into a soliton - like packet of excitations @xcite . within spin chains , |
1,315 | Suppose that you have an abstract for a scientific paper: the use of jet modification to study the properties of dense matter is reviewed .
different sets of jet correlations measurements which may be used to obtain both the space - time and momentum space structure of the produced matter are outlined . .
And you have already written the first three sentences of the full article: it is now established that the collision of heavy - ions at the relativistic heavy - ion collider have led to the formation of an entirely new form of matter @xcite .
while the underlying degrees of freedom prevalent in the hot plasma are , as yet , unknown @xcite , various constraints may be imposed through a study of its partonic substructure .
the foremost tool in this study is the modification of the hard jets , usually referred to as jet quenching @xcite ..
Please generate the next two sentences of the article | the number of hadrons with transverse momentum @xmath0 gev ( which , necessarily originate in the fragmentation of hard jets ) is reduced by almost a factor of 5 in central @xmath1-@xmath1 collisions , compared to that expected from elementary nucleon nucleon encounters enhanced by the number of expected binary collisions @xcite .
jet modification is a probe with a wide range of complexity in terms of experimental observables . by now |
1,316 | Suppose that you have an abstract for a scientific paper: we describe results from a fully self consistent three dimensional hydrodynamical simulation of the formation of one of the first stars in the universe .
dark matter dominated pre - galactic objects form because of gravitational instability from small initidal density perturbations . as they assemble via hierarchical merging , primordial gas cools through ro - vibrational lines of hydrogen molecules and sinks to the center of the dark matter potential well .
the high redshift analog of a molecular cloud is formed .
when the dense , central parts of the cold gas cloud become self - gravitating , a dense core of @xmath0 undergoes rapid contraction . at densities
@xmath1 a @xmath2 proto - stellar core becomes fully molecular due to three body formation .
contrary to analytical expectations this process does not lead to renewed fragmentation and only one star is formed .
the calculation is stopped when optical depth effects become important , leaving the final mass of the fully formed star somewhat uncertain . at this stage
the protostar is acreting material very rapidly ( @xmath3 ) .
radiative feedback from the star will not only halt its growth but also inhibit the formation of other stars in the same pre galactic object ( at least until the first star ends its life , presumably as a supernova ) .
we conclude that at most one massive ( @xmath4 ) metal free star forms per pre galactic halo ,
consistent with recent abundance measurements of metal poor galactic halo stars .
# 1_[#1 ] _
# 110^#1 # 1n _ # 1 # 1k_#1 # 1@xmath5 # 1_#1 _ # 1_#1 _ # 1_#1 _ = # 1 1.25 in .125 in .25 in .
And you have already written the first three sentences of the full article: chemical elements heavier than lithium are synthesized in stars .
such `` metals '' are observed at times when the universe was only @xmath6% of its current age in the inter galactic medium ( igm ) as absorption lines in quasar spectra ( see ellison et al . 2000 , and references therein ) .
hence , these heavy elements not only had to be synthesized but also released and distributed in the igm within the first billion years.
Please generate the next two sentences of the article | . only supernovae of sufficiently short lived massive stars are known to provide such an enrichment mechanism .
this leads to the prediction that _ the first generation of cosmic structures formed massive stars ( although not necessarily only massive stars ) . _ in the past 30 years it has been argued that the first cosmological objects form globular clusters ( ) , super massive black holes ( ) , or even low mass stars ( ) . this disagreement of theoretical studies might at first seem surprising . |
1,317 | Suppose that you have an abstract for a scientific paper: solid atomic hydrogen is one of the simplest systems to undergo a metal - insulator transition . near the transition
, the electronic degrees of freedom become strongly correlated and their description provides a difficult challenge for theoretical methods . as a result ,
the order and density of the phase transition are still subject to debate . in this work
we use diffusion quantum monte carlo to benchmark the transition between paramagnetic and anti - ferromagnetic body centered cubic atomic hydrogen in its ground state .
we locate the density of the transition by computing the equation of state for these two phases and identify the phase transition order by computing the band gap near the phase transition .
these benchmark results show that the phase transition is continuous and occurs at a wigner - seitz radius of @xmath0 .
we compare our results to previously reported density functional theory , hedin s gw approximation , and dynamical mean field theory results . the metal - insulator transition in body centered cubic ( bcc ) hydrogen
was first considered by mott @xcite . at high density , the system is metallic : the electrons are in the paramagnetic , conducting phase . as the lattice spacing
is increased the electrons localize on the hydrogen ions forming an anti - ferromagnetic , insulating phase .
predicting the order of the phase transition allows us to identify the qualitative nature of the transition : whether the transition is due to strong particle correlations , a mott insulator transition , or due to long range coulomb interactions , the band - insulator transition @xcite .
locating the precise transition density is a difficult test for an electronic structure method . since the original study ,
several closely related systems , finite lattices or 1d chains of hydrogen atoms , have become a standard test used to benchmark quantum chemistry methods @xcite .
unfortunately , current electronic structure methods such as density functional theory , dynamical mean field....
And you have already written the first three sentences of the full article: the early calculations by svane and gunnarson showed that when self - interaction corrections were included in the local density approximation , density functional theory ( dft ) predicted a first order phase transition located near the wigner - seitz radius @xmath1 where @xmath2 , @xmath3 is the density , and @xmath4 is the bohr radius @xcite . on the contrary , dft calculations using either
the generalized gradient approximation ( gga ) or local spin density approximation ( lsda ) without the self - interaction correction have predicted a second - order phase transition at @xmath5 and @xmath6 and an itenerant anti - ferromagnetic phase up to @xmath7 and @xmath8 respectively @xcite .
g@xmath9w@xmath9 , using the lda or gga orbitals to compute the initial green s function , finds the same transition order as their underlying dft functionals , though the phase transition density is shifted upwards to @xmath10 @xcite ..
Please generate the next two sentences of the article | the most recent set of g@xmath9w@xmath9 calculations begin with lda+u and gga+u single particle orbitals for the initial green s function @xcite .
the `` + u '' methods include an on - site repulsion for the two different spin densities to penalize double occupancy and pushes the system towards an anti - ferromagnetic state . |
1,318 | Suppose that you have an abstract for a scientific paper: recent results on searches for physics beyond the standard model obtained by the h1 and zeus experiments are reported here .
after a brief introduction to the hera collider , indirect searches for contact interactions and extra - dimensions are presented as well as direct searches for new physics including leptoquarks , lepton - flavour violation , squarks produced by r - parity violation and excited fermions .
new results from isolated lepton events and single top searches are also presented .
finally the future prospects of hera-2 are shown .
* search for new particles at hera * + mireille schneider + cppm , 163 , avenue de luminy , case 907 , + 13288 marseille cedex 9 , france .
And you have already written the first three sentences of the full article: hera is an @xmath0 collider which has especially high sensitivity to new particles coupling to lepton - quark pairs . in 1994
- 97 hera collided 27.5 gev positrons on 820 gev protons . in 1998
the proton energy was raised to 920 gev increasing the center - of - mass energy @xmath1 from 300 gev to 318 gev . in 1998 and in the first months of 1999 , hera ran with electrons . in.
Please generate the next two sentences of the article | may 1999 hera switched back to @xmath2 collisions .
the three main colliding periods as well as the corresponding luminosities for each experiment are summarized in table [ tab : lumit ] . * * . _ |
1,319 | Suppose that you have an abstract for a scientific paper: the simultaneous detection of electromagnetic and gravitational wave emission from merging neutron star binaries would aid greatly in their discovery and interpretation . by studying turbulent amplification of magnetic fields in local high - resolution simulations of neutron star merger conditions ,
we demonstrate that magnetar - level ( @xmath0 g ) fields are present throughout the merger duration .
we find that the small - scale turbulent dynamo converts 60% of the randomized kinetic energy into magnetic fields on a merger time scale .
since turbulent magnetic energy dissipates through reconnection events which accelerate relativistic electrons , turbulence may facilitate the conversion of orbital kinetic energy into radiation .
if @xmath1 of the @xmath2 erg of orbital kinetic available gets processed through reconnection , and creates radiation in the 15 - 150 kev band , then the fluence at 200 mpc would be @xmath3 , potentially rendering most merging neutron stars in the advanced ligo and virgo detection volumes detectable by _ swift _ bat . .
And you have already written the first three sentences of the full article: the in - spiral and coalescence of binary neutron star systems is a topic of increasingly intensive research in observational and theoretical astrophysics .
it is anticipated that the first direct detections of gravitational wave ( gw ) will be from compact binary mergers .
binary neutron star ( bns ) mergers are also thought to produce short - hard gamma - ray bursts ( sgrb s ) @xcite ..
Please generate the next two sentences of the article | simultaneous detections of a prompt gravitational wave signal with a spatially coincident electromagnetic ( em ) counterpart dramatically increases the potential science return of the discovery .
for this reason , there has been considerable interest as to which , if any , detectable em signature may result from the merger @xcite . |
1,320 | Suppose that you have an abstract for a scientific paper: a generalized notion of oscillatory integrals that allows for inhomogeneous phase functions of arbitrary positive order is introduced . the wave front set of the resulting distributions
is characterized in a way that generalizes the well - known result for phase functions that are homogeneous of order one . .
And you have already written the first three sentences of the full article: oscillatory integrals play an important role in the theory of pseudodifferential operators .
they are also a useful tool in mathematical physics , in particular in quantum field theory , where they are used to give meaning to formal fourier integrals in the sense of distributions . for phase functions which are homogeneous of order one
, this also leads to a characterization of the wave front set of the resulting distribution , as it is known to be contained in the manifold of stationary phase of the phase function . in these applications ,.
Please generate the next two sentences of the article | the restriction to phase functions that are homogeneous of order one is often obstructive . in many cases ,
this restriction can be overcome by shifting a part of the would - be phase function to the symbol , cf . |
1,321 | Suppose that you have an abstract for a scientific paper: in this paper the jessen s type inequality for normalized positive @xmath0-semigroups is obtained .
an adjoint of jessen s type inequality has also been derived for the corresponding adjoint - semigroup , which does not give the analogous results but the behavior is still interesting .
moreover , it is followed by some results regarding positive definiteness and exponential convexity of complex structures involving operators from a semigroup .
example.eps gsave newpath 20 20 moveto 20 220 lineto 220 220 lineto 220 20 lineto closepath 2 setlinewidth gsave .4 setgray fill grestore stroke grestore .
And you have already written the first three sentences of the full article: a significant theory regarding inequalities and exponential convexity for real valued functions , has been developed @xcite . the intention to generalize such concepts for the @xmath0-semigroup of operators ,
is motivated from @xcite .
+ in the present article , we shall derive a jessen s type inequality and the corresponding adjoint - inequality , for some @xmath0-semigroup and the adjoint - semigroup , respectively ..
Please generate the next two sentences of the article | + + the notion of banach lattice was introduced to get a common abstract setting , within which one could talk about the ordering of elements .
therefore , the phenomena related to positivity can be generalized . |
1,322 | Suppose that you have an abstract for a scientific paper: the problem of soliton - soliton force is revisited . from the exact two solitons solution of a nonautonomous gross - pitaevskii equation
, we derive a generalized formula for the mutual force between two solitons .
the force is given for arbitrary solitons amplitude difference , relative speed , phase , and separation .
the latter allows for the investigation of soliton molecules formation , dynamics , and stability .
we reveal the role of the time - dependent relative phase between the solitons in binding them in a soliton molecule .
we derive its equilibrium bond length , spring constant , frequency , effective mass , and binding energy of the molecule .
we investigate the molecule s stability against perturbations such as reflection from surfaces , scattering by barriers , and collisions with other solitons . .
And you have already written the first three sentences of the full article: the old - new interest in the problem of soliton - soliton intertaction and soliton molecules has been increasingly accumulating particularly over the past few years .
this is mainly motivated by the application of optical solitons as data carriers in optical fibers @xcite and the realization of matter - wave solitons in bose - einstein condensates @xcite .
one major problem limiting the high - bit rate data transfer in optical fibers is the soliton - soliton interaction . on the one hand ,.
Please generate the next two sentences of the article | soliton - soliton interaction is considered as a problem since it may destroy information coded by solitons sequences . on the other hand
, it is part of the problem s solution , since the interaction between solitons leads to the formation of stable soliton molecules which can be used as data carriers with larger `` alphabet '' @xcite . |
1,323 | Suppose that you have an abstract for a scientific paper: effects of the dzyaloshinski - moriya ( dm ) interaction on low - energy excitations in a one - dimensional orthogonal - dimer model are studied by using the perturbation expansions and the numerical diagonalization method . in the absence of the dm interaction ,
the triplet excitations show two flat spectra with three - fold degeneracy , which are labeled by magnetization @xmath0 . these spectra split into two branches with @xmath1 and with @xmath2 by switching - on of the dm interaction and besides the curvature appears in the triplet excitations with @xmath3 more strongly than those of @xmath1 . ,
, quantum spin ; low - energy excitation ; dzyaloshinski - moriya interaction ; .
And you have already written the first three sentences of the full article: since its discovery by kageyama _ et al_.@xcite , the spin dimer compound srcu@xmath4(bo@xmath5)@xmath4 has attracted much attention as a suitable material for frustrated spin systems in low dimension .
srcu@xmath4(bo@xmath5)@xmath4 exhibits various interesting phenomena , such as a quantum disordered ground state @xcite and a complex shape of magnetization curve@xcite , because of its unique crystal structure . in consideration of the structure , miyahara and
ueda suggested that the magnetic properties of the spin dimer compound srcu@xmath4(bo@xmath5)@xmath4 can be described as a spin-@xmath6 two - dimensional ( 2d ) orthogonal - dimer model @xcite , equivalent to the shastry - sutherland model on square lattice with some diagonal bonds @xcite ..
Please generate the next two sentences of the article | the ground state of the shastry - sutherland model in dimer phase is exactly represented by a direct product of singlets .
the low - energy dispersions possess six - fold degeneracy and are almost flat reflecting that the triplet tends to localize on vertical or horizontal bonds . |
1,324 | Suppose that you have an abstract for a scientific paper: we possess convincing experimental evidence for the fact that the real photon has non - trivial parton structure .
on the other hand , interactions of the cosmic microwave background photons with high energy particles propagating through the universe play an important role in astrophysics . in this context , to invoke the parton content could be convenient for calculations of the probabilities of different processes involving these photons . as an example , the cross section of inclusive resonant @xmath0 boson production in the reaction @xmath1 is calculated by using the parton language .
neutrino
photon deep inelastic scattering is considered . .
And you have already written the first three sentences of the full article: the parton model , according to which hadrons consist of quarks antiquarks and gluons ( partons ) , bound together in different ways , has been very successful in reproducing experiment .
this provides a relatively explicit and transparent technique for the description of high energy particle interactions .
the distributions of partons inside hadrons are characterized by the structure functions satisfying the dokshitzer .
Please generate the next two sentences of the article | gribov lipatov
altarelli parisi ( dglap ) equations @xcite or ones that are basically similar . |
1,325 | Suppose that you have an abstract for a scientific paper: we calculate the image of the combinatorial @xmath0-matrix for any classical highest weight element in the tensor product of kirillov reshetikhin crystals @xmath1 of type @xmath2 .
the notion of @xmath3-diagrams is effectively used for the identification of classical highest weight elements in @xmath4 . .
And you have already written the first three sentences of the full article: let @xmath5 be the quantum enveloping algebra associated to an affine algebra @xmath6 without derivation .
let @xmath7 be finite - dimensional @xmath5-modules .
suppose @xmath8 is irreducible and @xmath7 have crystal bases @xmath9 ..
Please generate the next two sentences of the article | then it is known @xcite that there exists a unique map @xmath0 from @xmath10 to @xmath11 commuting with any crystal operators @xmath12 and @xmath13 .
there also exists an integer - valued function @xmath14 on @xmath10 , called energy function , satisfying a certain recurrence relation under the action of @xmath12 ( see ) . |
1,326 | Suppose that you have an abstract for a scientific paper: we recover the joint and individual space density and surface brightness distribution(s ) of galaxies from the millennium galaxy catalogue .
the mgc is a local survey spanning 30.9 deg@xmath0 and probing approximately one two mag arcsec@xmath1 deeper than either the two - degree field galaxy redshift survey ( 2dfgrs ) or the sloan digital sky survey ( sdss ) .
the mgc contains @xmath2 galaxies to @xmath3 mag with @xmath4 per cent spectroscopic completeness . for each galaxy
we derive individual @xmath5-corrections and seeing - corrected sizes .
we implement a joint luminosity - surface brightness step - wise maximum likelihood method to recover the bivariate brightness distribution ( bbd ) inclusive of most selection effects . integrating the bbd over surface brightness
we recover the following schechter function parameters : @xmath6 mpc@xmath7 , @xmath8 mag and @xmath9 .
compared to the 2dfgrs @xcite we find a consistent @xmath10 value but a slightly flatter faint - end slope and a higher normalisation , resulting in a final luminosity density @xmath11 mpc@xmath7 marginally higher than , but consistent with , the earlier 2dfgrs ( @xcite ) , esp ( @xcite ) , and sdss @xmath12 @xcite results .
the mgc is inconsistent with the sdss @xmath13 result ( @xmath14 ) if one adopts the derived sdss evolution ( @xcite ) .
the mgc surface brightness distribution is a well bounded gaussian at the @xmath10 point with @xmath15 mpc@xmath7 , @xmath16 mag arcsec@xmath1 and @xmath17 .
the characteristic surface brightness for luminous systems is invariant to @xmath18 mag faintwards of which it moves to lower surface brightness .
the surface brightness distribution also broadens ( @xmath19 ) towards lower luminosities .
the luminosity dependence of @xmath20 provides a new constraint for both the theoretical development ( dalcanton , spergel & summers 1997 ; mo , mao & white 1998 ) and numerical simulations ( e.g. , @xcite ) which typically predict a mass - independent @xmath21 ( see....
And you have already written the first three sentences of the full article: the recognised convention for representing the overall galaxy population is the luminosity distribution or space density of galaxies ( see review by binggeli , sandage & tammann 1988 and more recently @xcite ) .
this distribution is typically derived from a magnitude limited redshift survey which is corrected for malmquist bias ( e.g. , efstathiou , ellis & peterson 1988 ) and fitted with the three parameter schechter function @xcite .
generally , the schechter function is found to be a formally good representation , although some surveys ( e.g. , @xcite ; @xcite ) have hinted at an upturn at the faintest limits , where the statistics become poor ( typically @xmath25 mag , see also @xcite ) ..
Please generate the next two sentences of the article | the process of fitting a luminosity function ( lf ) reduces the galaxy population to three crucial numbers : the characteristic luminosity , @xmath10 ( or @xmath26 ) , the normalisation , @xmath27 , and the faint - end slope , @xmath28 . since the pioneering work of @xcite numerous measurements of these three crucial parameters have been made ( see @xcite ) . among the most recent are those derived from the two - degree field galaxy redshift survey ( 2dfgrs ; @xcite ) and the sloan digital sky survey ( sdss1&2 ; @xcite ; 2003a ) .
however , although individual surveys yield schechter function parameters to high accuracy , a comparison between independently published values shows excessively large variations , indicative of strong systematic errors ( see @xcite ; @xcite ; @xcite ) . @xcite |
1,327 | Suppose that you have an abstract for a scientific paper: we present the cxocy j220132.8 - 320144 system , which is composed of an edge - on spiral galaxy at @xmath0 lensing a @xmath1 background quasar .
two images of the quasar are seen .
the geometry of the system is favorable to separate the relative mass contribution of the disk and halo in the inner parts of the galaxy .
we model the system with one elliptical mass component with the same ellipticity as the light distribution and manage to reproduce the quasar image positions and fluxes .
we also model the system with two mass components , disk and halo .
again , we manage to reproduce the quasar image positions and fluxes .
however , all models predict at least a third visible image close to the disk that is not seen in our images . we speculate that this is most likely due to extinction by the disk .
we also measure the rotational velocity of the galaxy at 2.7 disk scale radius to be @xmath2 km s@xmath3 from the [ oii ] emission lines . when adding the rotational velocity constraint to the models , we find that the contribution to the rotational velocity of the disk is likely to be equal to or larger than the contribution of the halo at this radius .
the detection of the third image and a more accurate measurement of the rotational velocity would help to set tighter constraints on the mass distribution of this edge - on spiral galaxy . .
And you have already written the first three sentences of the full article: the current picture of galaxies is that they are composed of baryons ( stars , gas , dust ) and non baryonic dark matter . while observationally the distribution of the baryons can be studied , it is difficult to probe how the dark matter is distributed compared to the baryons . traditionally , the study of galaxy dynamics has been the strongest proof of the existence of dark matter in galaxies ( e.g. , @xcite ; @xcite ; @xcite ) . but given the inherent degeneracies in the inversion of dynamical data to obtain density profiles , it is hard to measure how the dark matter is distributed .
another approach is to use gravitational lens systems . for strongly lensed quasars ( qsos ) , the geometry and photometric properties of the lens system
depend on the projected mass inside the lensed qso images and therefore can be used to constrain the mass distribution . for the particular case of spiral galaxies , generally composed of a bulge , a disk and a dark matter halo.
Please generate the next two sentences of the article | , the rotational velocity curves can not disentangle the relative contributions of the different mass components in the inner ( luminous ) parts of the galaxy . on the other hand ,
gravitational lenses offer the possibility of doing so , especially in the case of edge - on spirals . |
1,328 | Suppose that you have an abstract for a scientific paper: using a configuration interaction approach we study statistics of the dipole matrix elements ( @xmath0 amplitudes ) between the 14 lower states with @xmath1 and 21st to 100th even states with @xmath2 in the ce atom ( 1120 lines ) .
we show that the distribution of the matrix elements is close to gaussian , although the width of the gaussian distribution , i.e. the root - mean - square matrix element , changes with the excitation energy .
the corresponding line strengths are distributed according to the porter - thomas law which describes statistics of transition strengths between chaotic states in compound nuclei .
we also show how to use a statistical theory to calculate mean squared values of the matrix elements or transition amplitudes between chaotic many - body states .
we draw some support for our conclusions from the analysis of the 228 experimental line strengths in ce [ j. opt .
. am . *
8 * , 1545 ( 1991 ) ] , although direct comparison with the calculations is impeded by incompleteness of the experimental data .
nevertheless , the statistics observed evidence that highly excited many - electron states in atoms are indeed chaotic . .
And you have already written the first three sentences of the full article: the aim of this work is to present more evidence that excitation spectra of complex open - shell atoms , and probably any other atom at sufficient excitation energies , display clear quantum chaotic features .
this phenomenon is caused by strong mixing of many - electron excited states by the residual two - body coulomb interaction .
it manifests in particular in a gaussian statistics of the @xmath0 amplitudes for these states . since the time of bohr s hydrogen atom theory atoms were considered as perfectly regular dynamical systems ..
Please generate the next two sentences of the article | as the classical theory of chaos evolved it became apparent that highly excited atomic states in the rydberg range could become chaotic if an external field is applied @xcite , as long as the underlying classical motion is chaotic .
on the other hand , it was also due to bohr that the notion of compound nuclei was introduced in physics . |
1,329 | Suppose that you have an abstract for a scientific paper: we study black hole solutions in @xmath0 space , using an expansion to fourth order in the ratio of the radius of the horizon , @xmath1 , and the circumference of the compact dimension , @xmath2 .
a study of geometric and thermodynamic properties indicates that the black hole fills the space in the compact dimension at @xmath3 . at the same value of @xmath4 the entropies of the uniform black string and of the black hole are approximately equal .
And you have already written the first three sentences of the full article: if the topology of space - time is @xmath5 then the only known exact solution representing a black object is the uniform black string with horizon topology @xmath6 @xcite .
though this solution exists for all values of the mass it is unstable below a critical value , @xmath7 , as shown by gregory and laflamme @xcite .
horowitz and maeda @xcite argued that a uniform black string can not change its topology into a black hole in finite affine time , making the possibility of such a transition questionable ..
Please generate the next two sentences of the article | they suggested the possibility of a transition to a nonuniform black string .
gubser @xcite showed the existence of nonuniform black string solutions . |
1,330 | Suppose that you have an abstract for a scientific paper: we explore the static longitudinal and dynamic transverse spin susceptibilities in quantum dots and nanoparticles within the framework of the hamiltonian that extends the universal hamiltonian to the case of uniaxial anisotropic exchange . for the limiting cases of ising and heisenberg exchange interactions
we ascertain how fluctuations of single - particle levels affect the stoner instability in quantum dots .
we reduce the problem to the statistics of extrema of a certain gaussian process .
we prove that , in spite possible strong randomness of the single - particle levels , the spin susceptibility and all its moments diverge simultaneously at the point which is determined by the standard criterion of the stoner instability involving the mean level spacing only .
= 2000 .
And you have already written the first three sentences of the full article: the physics of quantum dots continuously attracted a lot of experimental and theoretical interest .
@xcite within the assumption that the thouless energy ( @xmath0 ) is much larger than mean single - particle level spacing ( @xmath1 ) , @xmath2 , an effective zero - dimensional hamiltonian has been derived .
@xcite in this so - called universal hamiltonian the electron - electron interaction that involves a set of matrix elements in the single - particle basis is reduced to just three parameters : the charging energy ( @xmath3 ) , the ferromagnetic exchange ( @xmath4 ) and the interaction in the cooper channel ..
Please generate the next two sentences of the article | the single particle energies are random quantities with wigner - dyson statistics .
thus the universal hamiltonian provides a convenient framework for the theoretical description of quantum dots . |
1,331 | Suppose that you have an abstract for a scientific paper: we investigate the effects of agn feedback on the colour evolution of galaxies found in local ( @xmath0 ) groups and clusters .
galaxies located within the lobes of powerful fanaroff - riley type ii ( edge - brightened ) sources show much redder colours than neighbouring galaxies that are not spatially coincident with the radio source .
by contrast , no similar effect is seen near fanaroff - riley type i ( core - dominated ) radio sources .
we show that these colours are consistent with fr - iis truncating star formation as the expanding bow shock overruns a galaxy .
we examine a sample of clusters with no detectable radio emission and show that galaxy colours in these clusters carry an imprint of past agn feedback .
agn activity in the low - redshift universe is predominantly driven by low - luminosity radio sources with short duty cycles .
our results show that , despite their rarity , feedback from powerful radio sources is an important driver of galaxy evolution even in the local volume .
galaxies : evolution galaxies : photometry galaxies : active .
And you have already written the first three sentences of the full article: there has been much recent interest in the properties of active galactic nuclei ( agn ) and the interaction between these objects and their host galaxies .
observationally , strong evidence supporting such interaction exists .
up to 70% of cd galaxies contain radio sources at their centres @xcite ..
Please generate the next two sentences of the article | these radio sources drive shocks into the intra - cluster medium ( icm ) , heating and transporting outward the cluster gas .
the spatial coincidence of radio emission with cavities in the hot x - ray emitting gas @xcite agrees well with analytical and numerical models @xcite , and is required to explain the lack of catastrophic cooling expected in the absence of a feedback mechanism in dense cluster cores @xcite . |
1,332 | Suppose that you have an abstract for a scientific paper: virtual network functions as a service ( vnfaas ) is currently under attentive study by telecommunications and cloud stakeholders as a promising business and technical direction consisting of providing network functions as a service on a cloud ( nfv infrastructure ) , instead of delivering standalone network appliances , in order to provide higher scalability and reduce maintenance costs .
however , the functioning of such nfvi hosting the vnfs is fundamental for all the services and applications running on top of it , forcing to guarantee a high availability level . indeed
the availability of an vnfaas relies on the failure rate of its single components , namely the servers , the virtualization software , and the communication network .
the proper assignment of the virtual machines implementing network functions to nfvi servers and their protection is essential to guarantee high availability .
we model the high availability virtual network function placement ( ha - vnfp ) as the problem of finding the best assignment of virtual machines to servers guaranteeing protection by replication .
we propose a probabilistic approach to measure the real availability of a system and design both efficient and effective algorithms that can be used by stakeholders for both online and offline planning . .
And you have already written the first three sentences of the full article: a recent trend in computer networks and cloud computing is to virtualize network functions , in order to provide higher scalability , reducing maintenance costs , and increasing reliability of network services .
virtual network functions as a service ( vnfaas ) is currently under attentive study by telecommunications and cloud stakeholders , as a promising business and technical direction consisting of providing network functions ( i.e. , firewall , intrusion detection , caching , gateways ... ) as a service instead of delivering standalone network appliances . while legacy network services are usually implemented by means of highly reliable hardware specifically built for a single purpose middlebox , vnfaas moves such services to a virtualized environment @xcite , named _
nfv infrastructure ( nfvi ) _ and based on commercial - off - the - shelf hardware @xcite ..
Please generate the next two sentences of the article | services implementing network functions are called _ virtual network functions ( vnfs)_. one of the open issues for nfvi design is indeed to guarantee high levels of vnf availability @xcite , i.e. , the probability that the network function is working at a given time .
in other words , a higher availability corresponds to a smaller downtime of the system , and it is required to satisfy stringent _ |
1,333 | Suppose that you have an abstract for a scientific paper: we revisit the shocked shell model for the class of active galactic nuclei known as gigahertz peak spectrum sources , incorporating new observational data on the radiation brightness temperatures .
we argue that in addition to free free absorption , induced compton scattering will also have an important effect in forming the @xmath0 ghz peak and in shaping the radio spectra that characterize these sources . indeed , our arguments suggest that gps sources may provide the first real evidence for the role of induced compton scattering in extragalactic radio sources . .
And you have already written the first three sentences of the full article: recently , bicknell , dopita , & odea ( 1997 ) developed a model which unifies the gigahertz peak spectrum ( gps ) sources and the related active galactic nuclei ( agn ) classes known as compact steep spectrum ( css ) sources and compact symmetric objects ( csos ) .
their model attributes the observed radio spectra and optical emission to the interaction of a jet driven , non thermal lobe with the ambient galactic interstellar medium ( ism ) . as the radio lobe forces its way through the ism , strong radiative shocks create shells of shock ionized and photo ionized gas which produce a low frequency break in the power law spectrum through free free absorption ( ffa ) .
although synchrotron self absorption ( ssa ) provides a natural mechanism to produce a low frequency break in a non thermal spectrum and is successful in explaining the spectra of agn with distinct core .
Please generate the next two sentences of the article | jet morphologies ( @xcite ) , we expect that it is unimportant in the more extended jet lobes of gps sources , where the non thermal plasma is more likely to be optically thin to its own radiation .
however , the spectrum emitted by the non thermal lobe plasma can still exhibit a low frequency break not only as a result of ffa in an external shell of thermal gas surrounding the lobe , as suggested by bicknell et al . |
1,334 | Suppose that you have an abstract for a scientific paper: we present the spectral energy distribution ( sed ) of the pre - planetary nebula , iras 19475 + 3119 ( i19475 ) , from the optical to the far - infrared .
we identify emission features due to crystalline silicates in the iso sws spectra of the star .
we have fitted the sed of i19475 using a 1-d radiative transfer code , and find that a shell with inner and outer radii of 8.8@xmath0 and 4.4 @xmath1 cm , and dust temperatures ranging from about 94k to 46k provide the best fit .
the mass of this shell is @xmath21[34 @xmath3 g@xmath4/@xmath5m)][@xmath6/200 ] , where @xmath7(100@xmath8 m ) is the 100@xmath8 m dust mass absorption coefficient ( per unit dust mass ) , and @xmath6 is the gas - to - dust ratio . in agreement with results from optical imaging and millimeter - wave observations of co emission of i19475
, our model fits support an r@xmath9 density law for its dust shell , with important implications for the interaction process between the fast collimated post - agb winds and the dense agb envelopes which results in the observed shapes of ppns and pns .
we find that the observed jcmt flux at sub - millimeter wavelengths ( 850 ) is a factor @xmath102 larger than our model flux , suggesting the presence of large dust grains in the dust shell of i19475 which are not accounted for by our adopted standard mrn grain size distribution . .
And you have already written the first three sentences of the full article: pre - planetary nebulae ( ppns ) , objects in transition between the agb and planetary nebula ( pn ) evolutionary phases , hold the key to our understanding of the relationship between these late evolutionary stages of low and intermediate mass ( @xmath11 ) stars . the hydrodynamic interaction of one or more fast , collimated post - agb outflows , believed to occur during the ppn phase , with the dense , massive , slowly - expanding spherical agb wind is believed to be responsible for shaping planetary nebulae ( sahai & trauger 1998 , sahai 2002 ) .
imaging surveys with the hubble space telescope have been crucial in revealing a wide variety of aspherical morphologies in ppns ( e.g. sahai 2004 ; ueta et al . 2000 ) , however the bulk of the circumstellar mass , which often resides in a spherical , dusty component surrounding the central aspherical nebula , is not well - probed in these data . thus a crucial ingredient for theoretical studies of such interactions , namely the mass and density of the ambient circumstellar medium ( e.g. , lee & sahai 2003 , 2004 ) , is lacking for a majority of the ppns discovered in hst surveys .
although attempts have been made to estimate the mass from submillimeter data ( e.g. gledhill et al ..
Please generate the next two sentences of the article | 2002 ) , these are compromised by the simplifying assumptions about the dust temperature .
the mineralogy of circumstellar dust shells around ppns became possible with the wavelength coverage and spectral resolution offered by the infrared space observatory ( iso ) ( see e.g. hrivnak et al . |
1,335 | Suppose that you have an abstract for a scientific paper: we present mean angular diameters for two cepheid variables , @xmath0 ursae minoris and @xmath1 geminorum , determined with the navy prototype optical interferometer ( npoi ) .
we present linear radii for these cepheids and two additional cepheids , @xmath2 cephei and @xmath3 aquilae , previously observed at the npoi .
we find the limb - darkened angular diameter of @xmath0 ursae minoris and of @xmath1 geminorum to be 3.28 @xmath4 0.02 and 1.55 @xmath4 0.09 milliarcseconds respectively .
using trigonometric parallaxes , we find the linear radii of @xmath0 ursae minoris , @xmath1 geminorum , @xmath2 cephei and @xmath3 aquilae to be 46 ( @xmath4 3 ) r@xmath5 , 60 ( + 25 , -14 ) r@xmath5 , 45 ( + 8 , -6 ) r@xmath5 , and 69 ( + 28 , -15 ) r@xmath5 respectively .
we compare the pulsation periods and linear radii of this sample of cepheids , which range in period from three to 11 days , to theoretical and empirical period - radius and period - radius - mass relations found in the literature .
we find that the observed diameter of @xmath0 ursae minoris is in excellent agreement with the predicted diameter as determined from both surface brightness techniques and theory only if @xmath0 ursae minoris is a first overtone pulsator . .
And you have already written the first three sentences of the full article: accurate stellar radii are important for the study of cepheid mass , pulsation and distance .
direct radius measurements of bright , nearby cepheids allows for comparison to radii found by indirect and/or theoretical methods such as numerical models @xcite , the infrared flux method @xcite and surface brightness relations @xcite .
these methods are easily applied to distant cepheids including those in nearby galaxies @xcite ..
Please generate the next two sentences of the article | each of these indirect methods results in period - radius and period - radius - mass relations which yield different radii , and different masses , at very small and very large periods . from
directly measured radii we may make comparisons with these relations . since there will always be cepheids too small or too faint for direct measurement , |
1,336 | Suppose that you have an abstract for a scientific paper: we report optical spectroscopic identifications of 10 hard ( 210 kev ) x - ray selected sources discovered by _
chandra_. the x - ray flux of the sources ranges between 1.5 and 25 @xmath0 , the lower value being 3 times fainter than in previous bepposax and asca surveys .
their r band magnitudes are in the range 12.822 .
six of the _ chandra _ sources are broad line quasars with redshifts between 0.42 and 1.19 , while the optical identification of the remaining four is quite varied : two are x - ray obscured , emission line agn at @xmath1=0.272 and @xmath1=0.683 , one is a starburst galaxy at @xmath1=0.016 and one , most unusually , is an apparently normal galaxy at @xmath1=0.158 .
these findings confirm and extend down to fainter x ray fluxes the bepposax results , in providing samples with a wide range of x - ray and optical properties .
the ratio between the soft x - ray and the optical luminosity of the @xmath1=0.158 galaxy is a factor at least 30 higher than that of normal galaxies , and similar to those of agn .
the high x
ray luminosity and the lack of optical emission lines suggest an agn in which either continuum beaming dominates , or emission lines are obscured or not efficiently produced .
x - rays : galaxies , cosmology : diffuse radiation , galaxies : quasars , galaxies : starburst .
And you have already written the first three sentences of the full article: the _ chandra _ x - ray observatory was launched on july 23 1999 , carrying on board a revolutionary high resolution mirror assembly , with a point spread function of 0.5 arcsec ( half power radius ) over the broad 0.1 to 10 kev band ( van speybroeck , et al .
this , together with the aspect camera which at the moment provides attitude solutions with errors of the order of 1 - 2 arcsec arcsec and the source positions should be better than 1 arcsec ] , allows the study of spatial extent of x - ray sources on similar scales , i.e. smaller or similar to the size of a l@xmath2 galaxy at any redshift ; and gives x - ray source positions at least as good as 23 arcsec , immediately allowing the unambiguous identification of the optical counterparts of faint x - ray sources .
consequently , the determination of the source redshifts via optical spectroscopy becomes highly efficient ..
Please generate the next two sentences of the article | the improvement provided by _
chandra _ is especially significant in the hard ( 210 kev ) x - ray band . |
1,337 | Suppose that you have an abstract for a scientific paper: the propensity of single domain globular proteins , the workhorses in cells , to be compact is the key reason that their folded states achieve high packing density . it is known that the radius of gyration , @xmath0 , of both the folded and unfolded ( created by adding denaturants ) states increase as @xmath1 where @xmath2 is the number of amino acids in the protein .
the values of the celebrated flory exponent @xmath3 are , respectively , @xmath4 and @xmath5 in the folded and unfolded states , which coincide with those found in homopolymers in poor and good solvents .
however , the extent of compaction of the unfolded state of a protein under low denaturant concentration , conditions favoring the formation of the folded state , is unknown .
this problem which goes to the heart of how proteins fold and has implications for the evolution of foldable sequences is unsolved .
we develop a theory based on polymer physics concepts that uses the contact map of proteins as input to quantitatively assess collapsibility of proteins .
the model , which includes only two - body excluded volume interaction and interactions reflecting the strength of the contact map , has only expanded and compact states .
surprisingly , we find that although protein collapsibility is universal , the propensity to be compact depends on the protein architecture .
application of the theory to over two thousand proteins shows that the extent of collapsibility depends not only on @xmath2 but also on the contact map reflecting the native fold structure .
a major prediction of the theory is that @xmath6-sheet proteins are far more collapsible than structures dominated by @xmath7-helices .
the theory fully resolves the apparent controversy between conclusions reached using different experimental probes assessing the extent of compaction of a couple proteins .
in addition , it reveals that there are considerable similarities between the physical mechanisms of homopolymer and protein collapse .
the theory provides....
And you have already written the first three sentences of the full article: folded states of globular proteins , which are evolved ( slightly ) branched heteropolymers made from twenty amino acids , are roughly spherical and are nearly maximally compact with high packing densities @xcite . despite achieving high packing densities in the folded states ,
globular proteins tolerate large volume substitutions while retaining the native fold @xcite .
this is explained in a couple of interesting theoretical studies @xcite , which demonstrated that there is sufficient free volume in the folded state to accommodate mutations ..
Please generate the next two sentences of the article | collectively these and related studies show that folded proteins are compact .
when they unfold , which can be achieved upon addition of high concentrations of denaturants ( or applying a mechanical force ) , they swell adopting expanded conformations . the radius of gyration ( @xmath0 ) of a folded globular protein is well described by the flory law with @xmath8 @xmath9 @xcite , whereas in the swollen state @xmath10 , where @xmath11 is an effective monomer size and the flory exponent @xmath12 @xcite . |
1,338 | Suppose that you have an abstract for a scientific paper: in this paper we present a new measurement setup , where a transition - edge sensor detector array is used to detect x - rays in particle induced x - ray emission measurements with a 2 mev proton beam .
transition - edge sensors offer orders of magnitude improvement in energy resolution compared to conventional silicon or germanium detectors , making it possible to recognize spectral lines in materials analysis that have previously been impossible to resolve , and to get chemical information from the elements .
our sensors are cooled to the operation temperature ( @xmath0 65 mk ) with a cryogen - free adiabatic demagnetization refrigerator , which houses a specially designed x - ray snout that has a vacuum tight window to couple in the radiation . for the best pixel ,
the measured instrumental energy resolution was 3.06 ev full width at half maximum at 5.9 kev .
we discuss the current status of the project , benefits of transition - edge sensors when used in particle induced x - ray emission spectroscopy , and the results from the first measurements .
pacs numbers : 82.80.ej , 85.25.oj , 87.64.kd , .
And you have already written the first three sentences of the full article: in particle induced x - ray emission ( pixe ) measurements an energetic ion beam , normally a 14 mev hydrogen or helium ion - beam , is directed to the sample to be analyzed , and sample composition for elements typically heavier than na or mg can be determined by means of characteristic x - ray emission @xcite . over the last four decades pixe
has developed to become a standard tool for elemental analysis in many fields of science . in geology ,
art restoration and medical diagnostic , to name a few , pixe has been used to determine the elemental composition of samples @xcite ..
Please generate the next two sentences of the article | the development of micro - pixe , where the particle beam is focused to about 1 @xmath1 m diameter spot , has opened the possibility to raster the target in order to get the positional elemental information of the sample .
one interesting special feature of pixe is that it is possible to irradiate samples with ion beams in ambient conditions , thus making the analysis of biological and large specimens , like paintings , possible . |
1,339 | Suppose that you have an abstract for a scientific paper: we present an _ ab initio _ determination of the shear viscosity for the unitary fermi gas based on finite temperature quantum monte carlo ( qmc ) calculations and the kubo linear - response formalism .
the results are confronted with the bound for the shear viscosity originating from hydrodynamic fluctuations .
assuming smoothness of the frequency dependent shear viscosity @xmath0 , we show that the bound is violated in the low temperature regime and the violation occurs simultaneously with the onset of the cooper paring in the system . in order to preserve the hydrodynamic bound in qmc @xmath0
has to possess a sharp structure located in the vicinity of zero frequency which is not resolved by an analytic continuation procedure . .
And you have already written the first three sentences of the full article: the unitary fermi gas ( ufg ) is expected to be one of the most strongly correlated systems in nature as it saturates the unitarity bound for the @xmath1-wave cross section @xmath2 , where @xmath3 is the relative wave vector of scattering particles .
the strong correlations are responsible for a multitude of interesting phenomena .
the most surprising ones include the existence of the pseudogap regime between the superfluid state and the normal state @xcite and the nearly ideal hydrodynamic behavior @xcite ..
Please generate the next two sentences of the article | therefore the properties of the ufg attract enormous attention from several communities including atomic physics , nuclear physics , relativistic heavy - ion collisions , and high-@xmath4 superconductivity ( see review papers @xcite ) .
experimentally the ufg has been realized with trapped fermionic atoms by means of feshbach resonances @xcite and currently represents one of the most controllable quantum systems . |
1,340 | Suppose that you have an abstract for a scientific paper: accurate knowledge of time - variation in meridional flow - speed and profile is crucial for estimating a solar cycle s features , which are ultimately responsible for causing space climate variations .
however , no consensus has been reached yet about the sun s meridional circulation pattern observations and theories . by implementing an ensemble kalman filter ( enkf ) data assimilation in a babcock - leighton solar dynamo model using data assimilation research testbed ( dart ) framework
, we find that the best reconstruction of time - variation in meridional flow - speed can be obtained when ten or more observations are used with an updating time of 15 days and a @xmath0 observational error .
increasing ensemble - size from 16 to 160 improves reconstruction .
comparison of reconstructed flow - speed with `` true - state '' reveals that enkf data assimilation is very powerful for reconstructing meridional flow - speeds and suggests that it can be implemented for reconstructing spatio - temporal patterns of meridional circulation . .
And you have already written the first three sentences of the full article: in recent years simulations of babcock - leighton type flux - transport ( hereafter blft ) solar dynamos in both 2d and 3d @xcite demonstrated the crucial role the sun s global meridional circulation plays in determining solar cycle properties .
time variations in speed and profile of meridional circulation have profound influence on solar cycle length and amplitude .
the recent unusually long minimum between cycles 23 and 24 has been explained by implementing two plausible changes in meridional circulation , ( i ) by implementing the change from a two - celled profile in latitude in cycles 22 to a one - celled profile in cycle 23 @xcite , and ( ii ) by performing a vast number of simulations by introducing a flow - speed change with time during the declining phase of each cycle @xcite . accurately knowing the speed and profile variations of the meridional circulation would greatly improve prediction of solar cycle features ..
Please generate the next two sentences of the article | the meridional circulation has been observed in the photosphere and inside the upper convection zone in the latitude range from the equator to @xmath1 in each hemisphere @xcite .
however , the speed , pattern and time variations of the circulation at high latitudes and in the deeper convection zone are not known from observations yet . theoretical models of meridional circulation @xcite provide some knowledge , but the flow patterns derived from model outputs vary from model to model , primarily because of our lack of knowledge of viscosity and density profiles and thermodynamics in the solar interior , which are essential ingredients in such models . as differential rotation does not change much with time compared to meridional circulation , in this first study |
1,341 | Suppose that you have an abstract for a scientific paper: as an alternative to state - of - the - art laser frequency stabilisation using ultra - stable cavities , it has been proposed to exploit the non - linear effects from coupling of atoms with a narrow transition to an optical cavity .
here we have constructed such a system and observed non - linear phase shifts of a narrow optical line by strong coupling of a sample of strontium-88 atoms to an optical cavity .
the sample temperature of a few mk provides a domain where the doppler energy scale is several orders of magnitude larger than the narrow linewidth of the optical transition .
this makes the system sensitive to velocity dependent multi - photon scattering events ( dopplerons ) that affect the cavity field transmission and phase . by varying the number of atoms and the intra - cavity power we systematically study this non - linear phase signature which displays roughly the same features as for much lower temperature samples
this demonstration in a relatively simple system opens new possibilities for alternative routes to laser stabilization at the sub 100 mhz level and superradiant laser sources involving narrow line atoms .
the understanding of relevant motional effects obtained here has direct implications for other atomic clocks when used in relation with ultranarrow clock transitions .
state - of - the - art atomic clocks rely on highly coherent light sources to probe narrow optical transitions @xcite . however , these clocks are limited by the frequency noise of the interrogation oscillator through the dick effect @xcite .
only recently multi - atom optical clocks have surpassed single ion clocks in stability owing to the enhanced laser stability @xcite .
achieving a better stability has so far been hampered by thermal noise in the reference cavity used for laser stabilisation @xcite .
recent proposals suggest an alternative approach to laser stabilisation @xcite where atoms in an optical lattice are probed on the narrow clock transition inside an optical cavity .
this brings....
And you have already written the first three sentences of the full article: after loading the mot for @xmath46 s we shut off the mot beams and wait for @xmath47s before probing the atoms for @xmath47s .
the probe laser beam is split up after the cavity and sent to two detectors which allow for a low bandwidth detection ( @xmath48 mhz ) of the transmitted power and a high bandwidth detection ( @xmath49 mhz ) for the phase measurement .
the nice - ohms phase signal is obtained by generating fourier sidebands in the probe light at exactly the free spectral range ( fsr ) of our cavity at @xmath50 mhz using an eom ..
Please generate the next two sentences of the article | the carrier is tuned close to the atomic resonance and will experience a phase shift due to the atoms .
the sidebands , on the other hand , are far off resonance and will not be influenced by the atoms . |
1,342 | Suppose that you have an abstract for a scientific paper: we study the d - term effect on runaway directions of the f - term scalar potential .
a minimal renormalizable model is presented where supersymmetry is broken without any pseudomoduli .
the model is applied to the hidden sector of gauge mediation for spontaneously breaking r symmetry and generating nonvanishing gaugino masses at the one - loop order . .
And you have already written the first three sentences of the full article: supersymmetry is expected to be one of the key ingredients to describe physics beyond the standard model ( sm ) .
while tree - level supersymmetry breaking within the sm sector leads to light sfermions , the breaking sector is separated from the sm one and is mediated by some effective operators or quantum effects . among various mechanisms for realizing this scenario ,
the gauge mediation , relevant to this paper , is one of the most promising candidates with a strong prophetic power ( for a review , see @xcite ) ..
Please generate the next two sentences of the article | it is known that pseudomoduli directions are present in the supersymmetry - breaking vacuum of oraifeartaigh - like models with the canonical khler potential @xcite .
an important implication of this result is that , if such models are used as the hidden sector of gauge mediation , gaugino masses are generally suppressed or the vacuum is unstable somewhere along the pseudomoduli @xcite . |
1,343 | Suppose that you have an abstract for a scientific paper: millimeter wave very long baseline interferometry ( mm - vlbi ) provides access to the emission region surrounding sagittarius a * , the supermassive black hole at the center of the milky way , on sub - horizon scales .
recently , a closure phase of @xmath0 was reported on a triangle of earth - sized baselines ( smt - carma - jcmt ) representing a new constraint upon the structure and orientation of the emission region , independent from those provided by the previously measured @xmath1-vlbi visibility amplitudes alone . here
, we compare this to the closure phases associated with a class of physically motivated , radiatively inefficient accretion flow models , and present predictions for future mm - vlbi experiments with the developing _ event horizon telescope _
( eht ) .
we find that the accretion flow models are capable of producing a wide variety of closure phases on the smt - carma - jcmt triangle , and thus not all models are consistent with the recent observations .
however , those models that reproduce the @xmath1-vlbi visibility amplitudes overwhelmingly have smt - carma - jcmt closure phases between @xmath2 , and are therefore broadly consistent with all current mm - vlbi observations .
improving station sensitivity by factors of a few , achievable by increases in bandwidth and phasing together multiple antennas at individual sites , should result in physically relevant additional constraints upon the model parameters and eliminate the current @xmath3 ambiguity on the source orientation .
when additional stations are included , closure phases of order @xmath4@xmath5 are typical . in all cases
the eht will be able to measure these with sufficient precision to produce dramatic improvements in the constraints upon the spin of sgr a*. .
And you have already written the first three sentences of the full article: it has recently become possible to study the emission regions of a handful of black holes on sub - horizon scales with millimeter wave very long baseline interferometry ( mm - vlbi ) .
already , this technique has produced horizon - scale information on sagittarius a * ( sgr a * ) , the @xmath6 black hole located at the center of the milky way @xcite , using the _
arizona radio observatory sub - millimeter telescope _ ( smt ) on mount graham , arizona , _ james clerk maxwell telescope _ ( jcmt ) and _ sub - millimeter array _ ( sma ) atop mauna kea in hawaii , and the _ combined array for research in millimeter - wave astronomy _ ( carma ) in cedar flat , california @xcite . due to the limited signal - to - noise of these early experiments ,.
Please generate the next two sentences of the article | they have produced primarily visibility amplitudes , related to the modulus of the fourier transform of the intensity distribution of the source .
nevertheless , when analyzed in the context of physically motivated accretion flow models , they have resulted in dramatic constraints upon the spin orientation and magnitude @xcite . |
1,344 | Suppose that you have an abstract for a scientific paper: we present a deformation of the minkowski space as embedded into the conformal space ( in the formalism of twistors ) based in the quantum versions of the corresponding kinematic groups .
we compute explicitly the star product , whose poisson bracket is quadratic .
we show that the star product although defined on the polynomials can be extended differentiably .
finally we compute the eucliden and minkowskian real forms of the deformation . .
And you have already written the first three sentences of the full article: we consider the grassmannian @xmath0 , the set of two - planes inside @xmath1 .
a plane @xmath2 is given by two linearly independent vectors or by any two linear combinations of them that are independent , so @xmath3 there is a transitive action of @xmath4 ( or @xmath5 ) on @xmath0 .
@xmath6 if we consider a particular point @xmath7 @xmath8 @xmath9 we notice that the conformal group of space time , @xmath10 , has spin group @xmath11 ..
Please generate the next two sentences of the article | its complexification , @xmath12 , has spin group @xmath13 . how to extract the minkowski space from @xmath0 ?
notice that since the two vectors are independent , @xmath14 at least one of the @xmath15 determinants in this matrix is @xmath16 . |
1,345 | Suppose that you have an abstract for a scientific paper: we investigate current fluctuations in a three - terminal quantum dot in the sequential tunneling regime .
dynamical spin blockade can be induced when the spin - degeneracy of the dot states is lifted by a magnetic field .
this results in super - poissonian shot noise and positive zero - frequency cross - correlations .
our proposed setup can be realized with semiconductor quantum dots . .
And you have already written the first three sentences of the full article: non - equilibrium current noise in mesoscopic structures is a consequence of the discreteness of the charge carriers ( for reviews , see refs .
@xcite ) . for conductors with open channels the fermionic statistics of electrons results in a suppression of shot noise below the classical schottky limit @xcite .
this was first noted by khlus @xcite and lesovik @xcite for single channel conductors ..
Please generate the next two sentences of the article | subsequently , bttiker generalized this suppression for many - channel conductors @xcite .
mesoscopic conductors are often probed by two or more leads . |
1,346 | Suppose that you have an abstract for a scientific paper: iron nitride fe@xmath0n is studied by full - potential lapw method .
structure parameters , electronic and magnetic properties as well as hyperfine interaction parameters are obtained .
we observe perfect agreement with experimental results .
hypothetical fe@xmath0n structure was also calculated to study the influence of disordering effects on parameters of mssbauer spectra .
we performed detailed analysis of efg formation on fe nuclei including magnetization effects .
we show that the formation of n - fe - n local configuration is energetically favourable in nitrogen austenites .
* electronic structure , hyperfine interactions and disordering effects in iron nitride fe@xmath1n * + + + _ @xmath2 rostov state university of transport , narodnogo opolcheniya 2 , rostov - on - don , 344038 russia _ + .
And you have already written the first three sentences of the full article: face centered cubic ( fcc ) iron - based alloys are widely used for developing of stainless austenitic steels especially for using in critical temperature ranges , aggressive environment and other severe external conditions .
doping of these steels with light interstitial impurities ( c , n ) influence mechanics and kinetics of structure phase transitions in fe - based alloys .
distribution of carbon and nitrogen atoms in solid solutions influence electrical and mechanical properties of alloys ..
Please generate the next two sentences of the article | nitrogen doping enables to solve the problem of the strengthening of stainless steels .
investigation of the influence of nitrogen on physical properties of multicomponent systems is a complicated problem . |
1,347 | Suppose that you have an abstract for a scientific paper: we discuss how to formulate dirac fermion operator on a finite lattice such that it can provide a nonperturbative regularization for massless fermion interacting with a background gauge field . 11.15.ha , 11.30.rd , 11.30.fs .
And you have already written the first three sentences of the full article: consider a massless dirac fermion interacting with a background gauge field .
our present goal is to formulate a nonperturbatively regularized quantum field theory which at least satisfies the following physical constraints : \(a ) in the classical limit , it reproduces the classical physics of the action , @xmath0 \psi(x ) $ ] .
\(b ) for topologically trivial gauge backgrounds , and in the weak coupling limit , it agrees with the predictions of weak coupling perturbation theory of the action ..
Please generate the next two sentences of the article | \(c ) for topologically nontrivial gauge backgrounds , it possesses exact zero modes satisfying the atiyah - singer index theorem . although wilson s idea @xcite of formulating gauge theories on the spacetime lattice is the most successful nonperturbative regularization for pure gauge fields , putting massless dirac fermions @xcite on the lattice has been a notorious problem for more than twenty years .
the resolution of the lattice fermion problem first appeared in the context of the domain - wall fermion @xcite , and it motivated the overlap formalism @xcite which led to the construction of overlap - dirac operator @xcite in 1997 . |
1,348 | Suppose that you have an abstract for a scientific paper: neutrinos coupled to an underlying scalar field in the scenario for unification of mass varying dark matter and cosmon-_like _ dark energy is examined . in the presence of a tiny component of mass varying neutrinos ,
the conditions for the present cosmic acceleration and for the stability issue are reproduced .
it is assumed that _
sterile _ neutrinos behave like mass varying dark matter coupled to mass varying _ active _ neutrinos through the _ seesaw _ mechanism , in a kind of _ mixed _ dark matter sector .
the crucial point is that the dark matter mass may also exhibit a dynamical behavior driven by the scalar field .
the scalar field mediates the nontrivial coupling between the mixed dark matter and the dark energy responsible for the accelerated expansion of the universe .
the equation of state of perturbations reproduce the generalized chaplygin gas ( gcg ) cosmology so that all the effective results from the gcg paradigm are maintained , being perturbatively modified by neutrinos . .
And you have already written the first three sentences of the full article: the continuous search for the physical mechanism which sets the cosmic acceleration of the universe and the corresponding conditions for stability has stimulated interesting and sometimes fascinating discussions on cosmological models @xcite .
the dynamical mass attributed to neutrinos or dark matter @xcite can , for instance , regulate the time evolution of the dynamical dark energy providing the setup of the cosmic acceleration followed by the cosmological stability . in this context ,
the coupling of mass varying dark matter with neutrinos yields interesting relations between the present mass of neutrinos and the dark energy equation of state . in a previous issue.
Please generate the next two sentences of the article | @xcite , it was demonstrated that an effective generalized chaplygin gas ( gcg ) scenario @xcite can be reproduced in terms of a dynamical dark energy component @xmath0 with equation of state given by @xmath1 and a cold dark matter ( cdm ) component with a dynamical mass driven by the scalar field @xmath0 .
dark matter is , most often , not considered in the mass varying neutrino ( mavan ) models . |
1,349 | Suppose that you have an abstract for a scientific paper: the phase transition from a superfluid to a mott insulator has been observed in a @xmath0na bose - einstein condensate .
a dye laser detuned @xmath1 nm red of the na @xmath2s@xmath3p@xmath4 transition was used to form the three dimensional optical lattice .
the heating effects of the small detuning as well as the three - body decay processes constrained the timescale of the experiment .
certain lattice detunings were found to induce a large loss of atoms .
these loss features were shown to be due to photoassociation of atoms to vibrational levels in the na@xmath5 @xmath6 state . .
And you have already written the first three sentences of the full article: optical lattices have become a powerful tool to enhance the effects of interaction in ultracold atomic systems to create strong correlations and probe many - body physics beyond the mean - field theory @xcite . simply through varying the depth of the lattice potential ,
one changes the tunneling rate as well as the on - site interaction energy by changing the confinement of the atoms .
the strength of the atomic interaction can be directly tuned with a magnetic feshbach resonance @xcite . in comparison to @xmath7rb , which has been used in almost all experiments on optical lattices , @xmath0na has stronger and wider feshbach resonances that are experimentally accessible @xcite ..
Please generate the next two sentences of the article | one such resonance has been used to produce quantum degenerate na@xmath5 molecules @xcite .
therefore , a sodium condensate loaded into an optical lattice would be a rich and flexible system for studying strong correlations . |
1,350 | Suppose that you have an abstract for a scientific paper: a dilute polymer solution is modeled as a suspension of non - interacting hookean dumbbells and the effect of excluded volume is taken into account by incorporating a narrow gaussian repulsive potential between the beads of each dumbbell .
the narrow gaussian potential is a means of regularising a delta - function potential
it tends to the delta - function potential in the limit of the width parameter @xmath0 going to zero .
exact predictions of viscometric functions in simple shear flow are obtained with the help of a retarded motion expansion and by brownian dynamics simulations .
it is shown that for relatively small _ non - zero _ values of @xmath0 , the presence of excluded volume causes a _ swelling _ of the dumbbell at equilibrium , and _ shear thinning _ in simple shear flow . on the other hand ,
a delta function excluded volume potential does not lead to either swelling or to shear thinning .
approximate viscometric functions , obtained by assuming that the bead - connector vector is described by a gaussian non - equilibrium distribution function , are found to be accurate above a threshold value of @xmath0 , for a given value of the strength of excluded volume interaction , @xmath1 .
a first order perturbation expansion reveals that the gaussian approximation is exact to first order in @xmath1 .
the predictions of an alternative quadratic excluded volume potential suggested earlier by fixman ( j. chem .
phys . , 1966 , 45 , 785 ; 793 )
are also compared with those of the narrow gaussian potential . .
And you have already written the first three sentences of the full article: the fact that two parts of a polymer chain can not occupy the same place at the same time due to their finite volume has been recognised in the polymer literature for many years now as being an extremely important microscopic phenomenon that governs the macroscopic behavior of polymer solutions @xcite . like hydrodynamic interaction ,
the _ excluded volume _
effect influences the properties of polymer solutions even in the limit of extremely long chains because it is responsible for segments remote from each other along the polymer chain interacting with each other ..
Please generate the next two sentences of the article | while the effect of excluded volume on static properties of polymer solutions has been widely studied , there have been very few attempts at examining its influence on properties far from equilibrium .
excluded volume effects can be incorporated into bead - spring chain models for polymer solutions in a relatively straightforward manner by adding the excluded volume interaction force between a particular bead and all the other beads in the chain ( pairwise ) to the other potential forces that are acting on the bead . |
1,351 | Suppose that you have an abstract for a scientific paper: the dynamics of the second order rational difference equation @xmath0 with complex parameters and arbitrary complex initial conditions is investigated . in the complex set up , the local asymptotic stability and boundedness are studied vividly for this difference equation .
several interesting characteristics of the solutions of this equation , using computations , which does not arise when we consider the same equation with positive real parameters and initial conditions are shown .
the chaotic solutions of the difference equation is absolutely new feature in the complex set up which is also shown in this article
. some of the interesting observations led us to pose some open interesting problems regarding chaotic and higher order periodic solutions and global asymptotic convergence of this equation . .
And you have already written the first three sentences of the full article: a rational difference equation is a nonlinear difference equation of the form @xmath1 where the initial conditions @xmath2 are such that the denominator never vanishes for any @xmath3 .
+ consider the equation @xmath4 where all the parameters and the initial conditions @xmath5 and @xmath6 are arbitrary complex number . this second order rational difference equation eq.([equation : total - equationa ] )
is studied when the parameters are real numbers and initial conditions are non - negative real numbers in @xcite . in this present article.
Please generate the next two sentences of the article | it is an attempt to understand the same in the complex plane . + here , a very brief review of some well known results which will be useful in order to apprehend the behavior of solutions of the difference equation ( [ equation : total - equationa ] ) .
let @xmath7 where @xmath8 be a continuously differentiable function . |
1,352 | Suppose that you have an abstract for a scientific paper: we introduce the problem of estimation of the parameters of a dynamically selected population in an infinite sequence of random variables and provide its application in the statistical inference based on record values from a non - stationary scheme .
we develop unbiased estimation of the parameters of the dynamically selected population and evaluate the risk of the estimators .
we provide comparisons with natural estimators and obtain asymptotic results .
finally , we illustrate the applicability of the results using real data .
* keywords : * extreme value theory , general record models , partial maxima , pfeifer model , selected population , uniformly minimum variance unbiased estimator . .
And you have already written the first three sentences of the full article: the problem of estimating parameters of selected populations has wide practical applications in estimation of experimental data in agriculture , industry and medicine .
some of the real world applications of this theory are the problem of estimating the average yield of a selected variety of plant with maximum yield ( kumar and kar , 2001 ) , estimating the average fuel efficiency of the vehicle with minimum fuel consumption ( kumar and gangopadhyay , 2005 ) and selecting the regimen with maximal efficacy or minimal toxicity from a set of regimens and estimating a treatment effect for the selected regimen ( sill and sampson , 2007 ) .
the problem of estimation after selection has received considerable attention by many researches in the past three decades ..
Please generate the next two sentences of the article | interested readers are referred to , for example , gibbons et al .
( 1977 ) for more details . |
1,353 | Suppose that you have an abstract for a scientific paper: we use supersymmetry transformations to obtain new one parameter family of inhomogeneous magnetic fields @xmath0 for which the massless dirac electron possesses exact solution .
the inhomogeneity appearing in @xmath1 can be controlled by the parameter @xmath2 .
the obtained magnetic fields are interpreted as deformed variants of some physically attainable well known magnetic fields .
a particular example , when a constant magnetic field is deformed , is considered to show that equidistant landau levels exist even in the presence of an infinite number of specially designed inhomogeneous magnetic fields . .
And you have already written the first three sentences of the full article: in recent years , interest in studying graphene has increased steeply due to its exceptional electronic properties and potentially significant applications in nanotechnology .
graphene , a single layer of carbon atoms arranged in a hexagonal honeycomb lattices , is the thinnest known material in the universe and the strongest ever measured @xcite . in the low energy approximation ,
the tight - binding description of the electron transport in graphene is reduced to the massless dirac - weyl equation with fermi velocity @xmath3 ..
Please generate the next two sentences of the article | the relatively low fermi velocity and the gapless linear energy dispersion near the dirac points @xmath4 and @xmath5 , enabled one to simulate relativistic effects like anomalous landau - hall effect @xcite , the zitterbewegung and the klein paradox @xcite , in condensed matter systems .
the optical - like behavior of electron waves in graphene - based waveguide structure has also been experimentally investigated @xcite . |
1,354 | Suppose that you have an abstract for a scientific paper: we use fabry - perot h@xmath0spectroscopy , complemented with published radio synthesis observations to derive high resolution rotation curves of spiral galaxies .
we investigate precisely their inner mass distribution and compare it to cdm simulations predictions .
having verified the existence of the so - called core - cusp problem , we find that the dark halo density inner slope is related to the galaxy masses .
dwarf galaxies with @xmath1 km / s have halo density inner slope @xmath2 while galaxies with @xmath3 km / s are best fitted by @xmath4 . .
And you have already written the first three sentences of the full article: the dynamical masses of spiral galaxies are known to differ significantly from their visible masses .
the commonly accepted cause is the existence of a ellipsoidal halo of unseen matter in addition to the stars and gas .
the exact density distribution of these halos have become an increasingly important issue ..
Please generate the next two sentences of the article | on one side , n - body simulations of the cosmological evolution of the cold dark matter ( cdm ) have now reached a sufficient resolution to predict the dark halo density profiles down to a scale corresponding to the inner parts of the spiral galaxies ( fukushige et al . 1997 ; navarro et al .
1997 ; moore et al . 1998 ; ghigna et al . |
1,355 | Suppose that you have an abstract for a scientific paper: ' '' '' * we report upon a novel realization of a fast nondeterministic random number generator whose randomness relies on intrinsic randomness of the quantum physical processes of photonic emission in semiconductors and subsequent detection by the photoelectric effect .
timing information of detected photons is used to generate binary random digits - bits . the bit extraction method based on the restartable clock method
theoretically eliminates both bias and autocorrelation while reaching efficiency of almost 0.5 bits per random event .
a prototype has been built and statistically tested . * .
And you have already written the first three sentences of the full article: true random numbers , or more precisely nondeterministic random number generators , seem to be of an ever increasing importance .
random numbers are essential in cryptography ( both classical and quantum ) , monte carlo numerical simulations and calculations , statistical research , randomized algorithms , lottery etc . + historically , there are two approaches to random number generation : algorithmic ( pseudorandom ) and by hardware ( nondeterministic ) .
pseudorandom number generators are well known in the art @xcite ..
Please generate the next two sentences of the article | a pseudorandom generator is nothing more than a mathematical formula which produces deterministic , periodic sequence of numbers which is completely determined by the initial state called _ seed_. by definition such generators are not provably random . in contrast to that , hardware generators extract randomness form physical processes believed to behave in nondeterministic way which makes them better candidates for true random number generation .
+ in applications where provability is essential , randomness sources ( if involved ) must also be provably random . for example the famous bb84 quantum key distribution protocol described in @xcite |
1,356 | Suppose that you have an abstract for a scientific paper: while the use of volatilities is pervasive throughout finance , our ability to determine the instantaneous volatility of stocks is nascent . here , we present a method for measuring the temporal behavior of stocks , and show that stock prices for 24 djia stocks follow a stochastic process that describes an efficiently priced stock while using a volatility that changes deterministically with time .
we find that the often observed , abnormally large kurtoses are due to temporal variations in the volatility .
our method can resolve changes in volatility and drift of the stocks as fast as a single day using daily close prices .
keywords : spectral analysis , noise reduction , rademacher distribution .
And you have already written the first three sentences of the full article: in this paper , we study the temporal behavior of the distribution of stock prices for 24 stocks in the dow jones industrial average ( djia ) .
this is done using a new method of measuring changes in the volatility and drifts of stocks with time . when this method is applied to time - series constructed from the daily close of stocks , changes as fast as one day
can be seen in both ..
Please generate the next two sentences of the article | given that it is not possible to accurately _ measure _ ( as oppose to _ predict _ ) intraday changes in the volatility using only daily - close data , for two of the 24 stocks we have been able to reach the maximum resolution ( known as the nyquist criteria ) of one day in the rate that the volatility can change , while for the great majority of the remaining stocks , we have come within one day of this maximum .
we believe that this method can measure changes in the volatility and drift that occur during the trading day as well if intraday price data is used . but |
1,357 | Suppose that you have an abstract for a scientific paper: the short wavelength cutoff has been introduced in the calculation of @xmath0 fluctuation conductivity of superconductors .
it is shown that a finite cutoff leads to a breakdown of the scaling property in frequency and temperature .
also , it increases the phase @xmath1 of the complex conductivity ( @xmath2 ) beyond @xmath3 at @xmath4 .
detailed expressions containing all essential parameters are derived for 3d isotropic and anisotropic fluctuation conductivity . in the _
2d _ case we obtain individual expressions for the fluctuation conductivity for each term in the sum over discrete wavevectors perpendicular to the film plane . a comparison of the theory to the experimental microwave fluctuation conductivity is provided . .
And you have already written the first three sentences of the full article: fluctuations of the order parameter near the critical temperature @xmath4 are much larger in high-@xmath4 superconductors than in classical low temperature superconductors .
one of the reasons lies in the higher thermal energy @xmath5 which provides the excitations , and the other in a very short coherence lengths which occur in high-@xmath4 cuprate superconductors . with these properties ,
the region of critical fluctuations was estimated from the ginzburg criterion to be of the order of 1k , or more , around @xmath4 , which renders the critical region accessible to experimental investigations.@xcite farther above @xmath4 , one expects to observe the transition from critical to noninteracting gaussian fluctuations which are the lowest order fluctuation corrections to the mean field theory.@xcite the layered structure of high-@xmath4 superconductors requires some theoretical sophistication ..
Please generate the next two sentences of the article | one could treat these superconductors with various models from three - dimensional ( 3d ) anisotropic to coupled layers lawrence - doniach , or purely two - dimensional ( _ 2d _ ) ones . due to the temperature variation of the coherence lengths
one could even expect a dimensional crossover in some systems . |
1,358 | Suppose that you have an abstract for a scientific paper: the modeling of complex atomic spectra is a difficult task , due to the huge number of levels and lines involved . in the presence of a magnetic field ,
the computation becomes even more difficult .
the anomalous zeeman pattern is a superposition of many absorption or emission profiles with different zeeman relative strengths , shifts , widths , asymmetries and sharpnesses .
we propose a statistical approach to study the effect of a magnetic field on the broadening of spectral lines and transition arrays in atomic spectra . in this model ,
the @xmath0 and @xmath1 profiles are described using the moments of the zeeman components , which depend on quantum numbers and land factors .
a graphical calculation of these moments , together with a statistical modeling of zeeman profiles as expansions in terms of hermite polynomials are presented .
it is shown that the procedure is more efficient , in terms of convergence and validity range , than the taylor - series expansion in powers of the magnetic field which was suggested in the past .
finally , a simple approximate method to estimate the contribution of a magnetic field to the width of transition arrays is proposed .
it relies on our recently published recursive technique for the numbering of ls - terms of an arbitrary configuration .
characterization of anomalous zeeman patterns in complex atomic spectra jean - christophe pain and franck gilleron cea , dam , dif , f-91297 arpajon , france .
And you have already written the first three sentences of the full article: in astrophysics , the observation of a splitting of spectral lines in the visible and uv ranges for a few white dwarfs @xcite confirmed the existence of intense magnetic fields ( 0.1 - 10@xmath2 mg ) as predicted by blackett @xcite .
the influence of a magnetic field on an atom modifies its emission or absorption lines .
thanks to this property , known as zeeman effect , the detection of magnetic fields is possible at large distances , through the measured radiation ..
Please generate the next two sentences of the article | the linear and quadratic zeeman effects @xcite explain the separation of spectral lines and enable one to determine a value of the magnetic field .
in the same way , pulsars and neutron stars having an even more intense magnetic field ( 10@xmath3 - 10@xmath4 mg ) have been discovered through their spectrum in the range of radio - frequencies and x - rays . |
1,359 | Suppose that you have an abstract for a scientific paper: * the adhesive and frictional response of an afm tip connected to a substrate through supramolecular host - guest complexes is investigated by dynamic monte carlo simulations .
the variation of the pull - off force with the unloading rate recently observed in experiments is here unraveled by evidencing a simultaneous ( progressive ) break of the bonds at fast ( slow ) rates .
the model reveals the origin of the observed plateaus in the retraction force as a function of tip - surface distance , showing that they ensue from the tip geometrical features . in lateral sliding ,
the model exhibits a wide range of dynamic behaviors ranging from smooth sliding to stick - slip at different velocities , with the average friction force determined by the characteristic formation / rupture rates of the complexes .
in particular , it is shown that for some molecular complexes friction can become almost constant over a wide range of velocities .
also , we show the possibility to exploit ageing effect through slide - hold - slide experiments , in order to infer the characteristic formation rate . finally , our model predicts a novel `` anti - ageing '' effect which is characterized by a decrease of static friction force with the hold time .
such effect is explained in terms of enhancement of adhesion during sliding , especially observed at high driving velocities . * .
And you have already written the first three sentences of the full article: the field of nanotribology evolved around attempts to understand the relationship between frictional forces and microscopic properties of systems.@xcite recent experimental and theoretical studies@xcite have suggested that the observed frictional phenomena might originate from the formation and rupture of microscopic bonds ( junctions ) that form between surfaces in close vicinity .
furthermore , these findings indicate that stick - slip motion is connected to a collective behavior of the bonds @xcite .
the formation and rupture of bonds are thermally activated processes and , thus , temperature may play an important role in the dynamics of friction at the nanoscale.@xcite friction is not simply the sum of single - bond responses , but is influenced by temporal and spatial dynamics across the entire ensemble of bonds that form the frictional interface ..
Please generate the next two sentences of the article | the way how individual bonds can be averaged to yield friction response has been the focus of intense research in the past decade,@xcite however many key aspects of the friction dynamics and its relation to the kinetics of bond formation and rupture are still not well understood .
one of the main difficulties in understanding and predicting frictional response is a lack of information on the nature of mediating bonds and their kinetic characteristic rates of formation and rupture . |
1,360 | Suppose that you have an abstract for a scientific paper: we calculate the parity - violating amplitudes in the @xmath0 interaction with pionless effective field theory to lo . matching the parity violating low energy constants to the ddh coefficients we make numerical predictions for parity - violating observables .
in particular we give predictions for the spin rotation of a neutron on a deuteron target , and target and beam asymmetries in @xmath0 scattering . .
And you have already written the first three sentences of the full article: hadronic parity - violation has been traditionally analyzed in terms of potential models ; specifically the ddh model@xcite , which is a parity violating single meson exchange picture containing seven phenomenological constants . however , there exist well known discrepancies between experimental measurements and the ddh model@xcite .
some of this discrepancy is no doubt due to nuclear physics uncertainties , but another source may be the use of the model - dependent ddh potential . a possible solution to these problems has recently been proposed by zhu et al.@xcite , restriction of experiments to nuclei with @xmath1 so that nuclear uncertainties are minimal , and analysis using a model - independent picture via effective field theory . at low energies , less than @xmath2
, such an approach is provided by pionless eft ( @xmath3 ) , which has been extremely successful at low energies in the two - body and three - body sector for parity - conserving interactions , including interactions with external currents@xcite . at low energies inclusion of parity - violation.
Please generate the next two sentences of the article | requires only five additional low energy constants ( lec s ) in the nucleon - nucleon interaction .
these lec s involve all possible isospin structures that mix s and p waves with one derivative and are equivalent to the parameters originally posited by danilov@xcite . |
1,361 | Suppose that you have an abstract for a scientific paper: over the last two decades , many unexpected relations between exotic smoothness , e.g. exotic @xmath0 , and quantum field theory were found . some of these relations are rooted in a relation to superstring theory and quantum gravity .
therefore one would expect that exotic smoothness is directly related to the quantization of general relativity . in this article
we will support this conjecture and develop a new approach to quantum gravity called _ smooth quantum gravity _ by using smooth 4-manifolds with an exotic smoothness structure .
in particular we discuss the appearance of a wildly embedded 3-manifold which we identify with a quantum state .
furthermore , we analyze this quantum state by using foliation theory and relate it to an element in an operator algebra . then we describe a set of geometric , non - commutative operators , the skein algebra , which can be used to determine the geometry of a 3-manifold .
this operator algebra can be understood as a deformation quantization of the classical poisson algebra of observables given by holonomies .
the structure of this operator algebra induces an action by using the quantized calculus of connes .
the scaling behavior of this action is analyzed to obtain the classical theory of general relativity ( grt ) for large scales .
this approach has some obvious properties : there are non - linear gravitons , a connection to lattice gauge field theory and a dimensional reduction from 4d to 2d .
some cosmological consequences like the appearance of an inflationary phase are also discussed . at the end
we will get the simple picture that the change from the standard @xmath0 to the exotic @xmath1 is a quantization of geometry .
_ on the occasion of the 80-th birthday of carl h. brans _ .
And you have already written the first three sentences of the full article: on the 25-th of november in 1915 , einstein presented his field equations , the basic equations of general relativity , to the prussian academy of sciences in berlin .
this equation had a tremendous impact on physics , in particular on cosmology .
the essence of the theory was expressed by wheeler by the words : _ spacetime tells matter how to move ; matter tells spacetime how to curve_. einsteins theory remained unchanged for about 40 years ..
Please generate the next two sentences of the article | then one started to investigate theories fulfilling mach s principle leading to a variable gravitational constant .
brans - dicke theory was the first realization of an extended einstein theory with variable gravitational constant ( jordans proposal was not widely known ) . |
1,362 | Suppose that you have an abstract for a scientific paper: we consider a sequence of quantized lorentzian pulses of non - interacting electrons impinging on a quantum point contact ( qpc ) and study the waiting time distribution ( wtd ) , for any transmission and any number of pulses . as the degree of overlap between the electronic wave functions
is tuned , the wtd reveals how the correlations between particles are modified . in the weak overlap regime ,
the wtd is made of several equidistant peaks , separated by the same period as the incoming pulses , contained in an almost exponentially decaying envelope . in the other limit
, the wtd of a single quantum channel subjected to a constant voltage is recovered . in both cases ,
the wtd stresses the difference between the fluctuations induced by the scatterer and the ones encoded in the incoming quantum state .
a clear cross - over between these two situations is studied with numerical and analytical calculations based on scattering theory . .
And you have already written the first three sentences of the full article: the past decade has been marked by the emergence of electron quantum optics . in the spirit of quantum optics with photons , it aims to generate and manipulate single electronic excitations in quantum coherent circuits for fundamental and applied science . as a first step to achieve this goal ,
several single electron sources have been implemented in sub - micron cavities , such as the so called quantum capacitor @xcite and others @xcite , or by applying a periodic sequence of lorentzian voltage pulses to an electronic reservoir in order to generate a clean and coherent train of electronic excitations @xcite . once injected into quantum circuits ,
such excitations can be used to study fundamental aspects of quantum mechanics such as entanglement @xcite , interference effects @xcite and quantum correlations @xcite or interaction effects @xcite and coherence properties @xcite which would be of great interest when it comes to applications in quantum electronics or information processing ..
Please generate the next two sentences of the article | however , due to quantum effects , it is now well established that charge transport at the nanoscale is a statistical process @xcite .
going beyond the knowledge of average currents is then unavoidable and extremely useful at the same time as pointed out by r. landauer in his famous quote `` the noise is the signal '' . |
1,363 | Suppose that you have an abstract for a scientific paper: development of the aarhus adiabatic pulsation code started around 1978 .
although the main features have been stable for more than a decade , development of the code is continuing , concerning numerical properties and output .
the code has been provided as a generally available package and has seen substantial use at a number of installations .
further development of the package , including bringing the documentation closer to being up to date , is planned as part of the helas coordination action . .
And you have already written the first three sentences of the full article: the goal of the development of the code was to have a simple and efficient tool for the computation of adiabatic oscillation frequencies and eigenfunctions for general stellar models , emphasizing also the accuracy of the results .
not surprisingly , given the long development period , the simplicity is now less evident .
however , the code offers considerable flexibility in the choice of integration method as well as ability to determine all frequencies of a given model , in a given range of degree and frequency ..
Please generate the next two sentences of the article | the choice of variables describing the equilibrium model and oscillations was to a large extent inspired by @xcite .
as discussed in section [ sec : eqmodel ] the equilibrium model is defined in terms of a minimal set of dimensionless variables , as well as by mass and radius of the model . |
1,364 | Suppose that you have an abstract for a scientific paper: kaon properties are studied within the framework of a fully covariant transport approach .
the kaon - nucleon potential is evaluated in two schemes , a chiral perturbative approach and an effective one - boson - exchange model .
isospin effects are explicitly accounted for in both models .
the transport calculations indicate a significant sensitivity of momentum distributions and total yields of @xmath0 isospin states on the choice of the kaon - nucleon interaction .
furthermore , isospin effects are rather moderate on absolute kaon yields , but appear on strangeness ratios .
this is an important issue in determining the high density symmetry energy from studies of strangeness production in heavy - ion collisions .
asymmetric nuclear matter , symmetry energy , relativistic heavy ion collisions , kaon - nucleon potential , strangeness production .
+ pacs numbers : * 25.75.-q * , * 21.65.+f * , 21.30.fe , 25.75.dw . .
And you have already written the first three sentences of the full article: the knowledge of the in - medium hadronic properties at supra - normal densities is of major importance for the understanding of ( nuclear ) astrophysics such as the physical mechanism of supernovae explosions and the physics of neutron stars @xcite .
strangeness production at intermediate energy heavy - ion collisions has been a very helpful tool in studying the hadronic equation of state ( eos ) and the properties of strangeness matter under extreme conditions of baryon density and temperature @xcite .
it is well established that ( @xmath0 ) kaons feel a weak repulsive potential of the order of @xmath1 mev at saturation density @xmath2 , as it has been verified by studying strangeness flows in heavy - ion collisions @xcite ..
Please generate the next two sentences of the article | the determination of the high density behavior of the nuclear eos has been successfully investigated in this context @xcite .
it has been realized that strangeness production could also serve as an important messenger for the isovector part of the nuclear eos at high densities , i.e. for the symmetry energy @xcite . |
1,365 | Suppose that you have an abstract for a scientific paper: wavelets are scaleable , oscillatory functions that deviate from zero only within a limited spatial regime and have average value zero , and thus may be used to simultaneously characterize the shape , location , and strength of astronomical sources .
but in addition to their use as source characterizers , wavelet functions are rapidly gaining currency within the source detection field .
wavelet - based source detection involves the correlation of scaled wavelet functions with binned , two - dimensional image data .
if the chosen wavelet function exhibits the property of vanishing moments , significantly non - zero correlation coefficients will be observed only where there are high - order variations in the data ; e.g. , they will be observed in the vicinity of sources .
source pixels are identified by comparing each correlation coefficient with its probability sampling distribution , which is a function of the ( estimated or _ a priori_-known ) background amplitude . in this paper
, we describe the mission - independent , wavelet - based source detection algorithm wavdetect , part of the freely available _ chandra interactive analysis of observations ( ciao ) _ software package .
our algorithm uses the marr , or
mexican hat " wavelet function , but may be adapted for use with other wavelet functions .
aspects of our algorithm include : ( 1 ) the computation of local , exposure - corrected normalized ( i.e. flat - fielded ) background maps ; ( 2 ) the correction for exposure variations within the field - of - view ( due to , e.g. , telescope support ribs or the edge of the field ) ; ( 3 ) its applicability within the low - counts regime , as it does not require a minimum number of background counts per pixel for the accurate computation of source detection thresholds ; ( 4 ) the generation of a source list in a manner that does not depend upon a detailed knowledge of the point spread function ( psf ) shape ; and ( 5 ) error analysis .
these features make our algorithm considerably more....
And you have already written the first three sentences of the full article: the detection and characterization of astronomical sources becomes increasingly difficult as we attempt to observe these sources in the euv , x - ray , and gamma - ray spectral regimes .
there are several reasons for this .
first , in these high - energy regimes , source data may consist of only a few counts , so that we must rely on the poisson distribution when making statistical inferences rather than using gaussian statistics that are considerably easier to apply , but that are strictly applicable only in the high - counts limit ..
Please generate the next two sentences of the article | second , spatially extended sources , such as supernova remnants and galaxy clusters , exhibit bright diffuse emission at high energies which may overlap with point sources , rendering the latter more difficult both to detect and characterize . and third , the present generation of broad - band high - energy telescopes , unlike optical telescopes , have spatially non - uniform point spread functions ( psfs ) as an unavoidable by - product of their design .
for instance , the psf of the wolter i - type high resolution mirror assembly ( hrma ) on the _ chandra x - ray observatory _ |
1,366 | Suppose that you have an abstract for a scientific paper: the search for cp - violating @xmath0 decay was performed with snd detector at vepp-2 m @xmath1 collider .
the total amount of data corresponding to 7 million produced @xmath2 mesons was analyzed .
no candidate events were found , giving an upper limit of the decay branching ratio : @xmath3 at 90% confidence level .
+ 13.25.es ; 11.30.er ; 13.65.+i ; 13.75.-n ; 14.40.aq + _ keywords : _
@xmath1 collisions ; kaon decays ; cp - violation ; upper limit .
And you have already written the first three sentences of the full article: at present cp - violation is observed only in the @xmath4 and @xmath5 decays , and first indication of the effect in b - decays was recently reported @xcite .
another possible domain for cp - violation studies are still unseeing @xmath6 and @xmath7 decays , of which the latter must be a pure cp - violating process @xcite , because for three neutral pions only cp - odd states exist .
cp - violation in the @xmath7 decay can be parameterized in terms of @xmath8 parameter , which is defined as : @xmath9 one can estimate the decay branching ratio @xcite : @xmath10 ..
Please generate the next two sentences of the article | the lowest existing experimental upper limit of @xmath11 was reported by cplear collaboration @xcite . in this
paper results of the study of the @xmath0 decay with the snd detector are presented . |
1,367 | Suppose that you have an abstract for a scientific paper: taking a clue from the pair of hi supershells found in the scd galaxy ngc 3556 ( m 108 ) , we propose a new mechanism for the origin of hi supershells in gas - rich massive galaxies . in this scenario ,
the two supershells were inflated out of the neutral hydrogen disk due to the localised flaring of a pair of radio lobes formed by the jets ejected from the nucleus during an active phase about @xmath0 years ago , but have faded away by now .
it is shown that the salient features of this supershell pair , such as their symmetrical locations about the galactic centre , the anomalously large energy requirements , the large galacto - centric distances , as well as the z - symmetric hemispherical shapes , find a more natural explanation in terms of this scenario , as compared to the standard models which postulate either a massive starburst , or the infall of external gas clouds .
other possible implications of this hypothesis are briefly discussed . .
And you have already written the first three sentences of the full article: an important manifestation of the activity inside the disks of gas - rich galaxies is their highly structured hi distribution , marked by cavities , shells and supershells .
first discovered in the milky way ( heiles 1979 , 1984 ) , such features are now known to exist in a number of spiral galaxies ( e.g. lehnert & heckman 1996 , irwin & seaquist 1990 , puche et al .
1992 , brinks & bajaja 1986 ) ..
Please generate the next two sentences of the article | exceptionally huge hi arcs and loops extending across several kiloparsecs have been identified with greater clarity in the hi images of a number of edge - on spirals , such as ngc 5775 ( irwin 1994 ) , ngc 4631 ( rand & van der hulst 1993 ) , ngc 3044 ( lee & irwin 1997 , hereafter li97 ) and ngc 3556 ( m 108 , king & irwin 1997 , hereafter ki97 ) . these have been interpreted as expanding supershells because of a loop - like or circular appearance in projection and either a persistence over a wide velocity range or , in a few cases , as some evidence for expansion in position - velocity space .
two main classes of explanations for the supershells posit the source of their kinetic energy to be , respectively , internal and external to the parent galaxy . |
1,368 | Suppose that you have an abstract for a scientific paper: we study bound magnetic polarons ( bmp ) in a very diluted magnetic semiconductor @xmath0 ( @xmath1 ) by means of site selective spectroscopy . in zero magnetic field
we detect a broad and asymmetric band with a characteristic spectral width of about 5 mev .
when external magnetic fields are applied a new line appears in the emission spectrum .
remarkably , the spectral width of this line is reduced greatly down to @xmath2 @xmath3 .
we attribute such unusual behavior to the formation of bmp , effected by sizable fluctuations of local magnetic moments .
the modifications of the optical spectra have been simulated by the monte - carlo method and calculated within an approach considering the nearest mn ion . a quantitative agreement with the experiment
is achieved without use of fitting parameters .
it is demonstrated that the low - energy part of the emission spectra originates from the energetic relaxation of a complex consisting of a hole and its nearest mn ion .
it is also shown that the contribution to the narrow line arises from the remote mn ions . .
And you have already written the first three sentences of the full article: an intriguing phenomenon in diluted magnetic semiconductors ( dms ) is the formation of bound magnetic polarons @xcite .
the bound magnetic polaron ( bmp ) is a local ordering of magnetic moments induced by the exchange interaction with a localized carrier .
most bmp studies , both experimental and theoretical , have been performed so far in a regime of the mean - field approach ( when @xmath4 ) @xcite . here.
Please generate the next two sentences of the article | , @xmath5 is the concentration of magnetic ions , @xmath6 is the concentration of cations , and @xmath7 is the localization radius .
this approach implies that the localized carrier interacts with a infinite number of @xmath8 ions , and hence it is typically applicable for high and moderate manganese concentrations ( @xmath9 ) . at present systems with a countable number of magnetic moments |
1,369 | Suppose that you have an abstract for a scientific paper: pour un groupe de kac - moody dploy ( au sens de j. tits ) sur un corps rellement valu quelconque , on construit une masure affine ordonne sur laquelle ce groupe agit
. cette construction gnralise celle dj effectue par s. gaussent et lauteur quand le corps rsiduel contient le corps des complexes @xcite et celle de f. bruhat et j. tits quand le groupe est rductif . on montre
que cette masure vrifie bien toutes les proprits des masures affines ordonnes comme dfinies dans @xcite . on utilise
le groupe de kac - moody maximal au sens do .
mathieu et on montre quelques rsultats pour celui - ci sur un corps quelconque ; en particulier on prouve , dans certains cas , un rsultat de simplicit pour ce groupe maximal . .
And you have already written the first three sentences of the full article: ltude des groupes de kac - moody sur un corps local a t initie par howard garland @xcite pour certains groupes de lacets .
dans @xcite on a construit un immeuble `` microaffine '' pour tous les groupes de kac - moody ( minimaux au sens de j. tits ) sur un corps muni dune valuation relle .
cest un immeuble ( en gnral non discret ) avec les bonnes proprits habituelles des immeubles ..
Please generate the next two sentences of the article | cependant cet immeuble microaffine nest pas lanalogue des immeubles de f. bruhat et j. tits pour les groupes rductifs .
il correspond plutt leur frontire dans la compactification de satake ou compactification polydrique . |
1,370 | Suppose that you have an abstract for a scientific paper: the effect of columnar pins on the flux - lines melting transition in high - temperature superconductors is studied using path integral monte carlo simulations .
we highlight the similarities and differences in the effects of columnar disorder on the melting transition in yba@xmath0cu@xmath1o@xmath2 ( ybco ) and the highly anisotropic bi@xmath0sr@xmath0cacu@xmath0o@xmath3 ( bscco ) at magnetic fields such that the mean separation between flux - lines is smaller than the penetration length . for pure systems , a first order transition from a flux - line solid to a liquid phase is seen as the temperature is increased . when adding columnar defects to the system , the transition temperature is not affected in both materials as long as the strength of an individual columnar defect ( expressed as a flux - line defect interaction ) is less than a certain threshold for a given density of randomly distributed columnar pins .
this threshold strength is lower for ybco than for bscco . for higher strengths the transition line
is shifted for both materials towards higher temperatures , and the sharp jump in energy , characteristic of a first order transition , gives way to a smoother and gradual rise of the energy , characteristic of a second order transition .
also , when columnar defects are present , the vortex solid phase is replaced by a pinned bose glass phase and this is manifested by a marked decrease in translational order and orientational order as measured by the appropriate structure factors . for bscco , we report an unusual rise of the translational order and the hexatic order just before the melting transition .
no such rise is observed in ybco . .
And you have already written the first three sentences of the full article: type ii superconductors @xcite allow for a partial penetration of magnetic field into the bulk of the superconducting ( sc ) material when the applied field @xmath4 satisfies @xmath5 . in a seminal work abrikosov @xcite
showed that when the ratio @xmath6 , where @xmath7 is the magnetic field penetration depth and @xmath8 is the coherence length , is greater than @xmath9 the magnetic field penetrates the sc material in the form of flux - lines ( fls ) .
these fls are also called vortices , since they are surrounded by circular currents ..
Please generate the next two sentences of the article | each fl carries a quantized unit of flux @xmath10 called the fluxoid .
the fls have cylindrical shape of radius @xmath11 ( the radius is not sharp since the magnetic field decays exponentially like @xmath12 , where r is the distance from the axis ) and a non - sc core of radius @xmath13 . |
1,371 | Suppose that you have an abstract for a scientific paper: we introduce a class of @xmath0-factorials , or @xmath0-pochhammer symbols , that includes many , if not most , well - known factorial and multiple factorial function variants as special cases .
we consider the combinatorial properties of the corresponding generalized classes of stirling numbers of the first kind which arise as the coefficients of the symbolic polynomial expansions of these @xmath1-factorial functions .
the combinatorial properties of these more general parameterized stirling number triangles we prove within the article include analogs to known expansions of the ordinary stirling numbers by @xmath2-order harmonic number sequences through the definition of a corresponding class of @xmath2-order @xmath1-harmonic numbers . we state and prove several new properties and functional equations enumerating these generalized @xmath1-harmonic number sequences with suggested corollaries of these results providing applications to generalized infinite euler - like sums expanded by their corresponding classes of infinite @xmath1-zeta and @xmath1-polylogarithm functions .
+ _ keywords : factorial ; multifactorial ; @xmath3-factorial ; pochhammer symbol ; stirling number ; generalized stirling number ; harmonic number ; @xmath1-harmonic number ; stirling polynomial . _ .
And you have already written the first three sentences of the full article: for any function , @xmath4 , and fixed non - zero indeterminates @xmath5 , we introduce and define the _ generalized @xmath0-factorial function _ , or alternately the _ @xmath0-pochhammer symbol _ , denoted by @xmath6 , as the following products : @xmath7 within this article , we are interested in the combinatorial properties of the coefficients of the powers of @xmath8 in the last product expansions which we consider to be generalized forms of the _ stirling numbers of the first kind _ in this setting .
section [ subsection_intro_gensnumsdefs ] defines generalized stirling numbers of both the first and second kinds and motivates the definitions of auxiliary triangles by special classes of formal power series generating function transformations and their corresponding negative - order variants considered in the references @xcite .
we observe that the definition of provides an effective generalization of many other related factorial function variants considered in the references when @xmath9 ..
Please generate the next two sentences of the article | the special cases of @xmath10 for some integer - valued @xmath11 and @xmath12 lead to the motivations for studying these more general factorial functions in @xcite , and form the expansions of multiple @xmath13-factorial functions , @xmath14 , studied in the triangular coefficient expansions defined by @xcite .
the _ factorial powers _ , or _ |
1,372 | Suppose that you have an abstract for a scientific paper: we present deep @xmath0 f555w ( @xmath1 ) and f814w ( @xmath2 ) observations of a central field in the local group dwarf spheroidal ( dsph ) galaxy leo i. the resulting color - magnitude diagram ( cmd ) reaches @xmath3 and reveals the oldest @xmath4 gyr old turnoffs .
nevertheless , a horizontal branch is not obvious in the cmd . given the low metallicity of the galaxy , this likely indicates that the first substantial star formation in the galaxy may have been somehow delayed in leo i in comparison with the other dsph satellites of the milky way .
the subgiant region is well and uniformly populated from the oldest turnoffs up to the 1 gyr old turnoff , indicating that star formation has proceeded in a continuous way , with possible variations in intensity but no big gaps between successive bursts , over the galaxy s lifetime .
the structure of the red - clump of core he - burning stars is consistent with the large amount of intermediate age population inferred from the main sequence and the subgiant region . in spite of the lack of gas in leo i
, the cmd clearly shows star formation continuing until 1 gyr ago and possibly until a few hundred myrs ago in the central part of the galaxy .
subject headings : galaxies : individual ( leo i ) ; galaxies : evolution ; galaxies : stellar content ; galaxies : photometry ; stars : hertzsprung - russell ( hr - diagram ) . .
And you have already written the first three sentences of the full article: the first color - magnitude diagrams ( cmd ) obtained by baade for the dwarf spheroidal ( dsph ) companions of the milky way , and in particular for the draco system ( baade & swope 1961 ) , showed all of the features present in the cmd s of globular clusters .
this , together with the presence of rr lyrae stars ( baade & hubble 1939 ; baade & swope 1961 ) led to the interpretation that dsph galaxies are essentially pure population ii systems . but baade ( 1963 ) noted that there are a number of characteristics in the stellar populations of dsph galaxies that differentiate them from globular clusters , including extreme red horizontal branches and the distinct characteristics of the variable stars . when carbon stars were discovered in dsph galaxies ,
these differences were recognized to be due to the presence of an intermediate - age population ( cannon , niss & norgaard nielsen 1980 ; aaronson , olszewski & hodge 1983 ; mould & aaronson 1983 ) . in the past few years this intermediate - age population has been shown beautifully in the cmds of a number of dsph galaxies ( carina : mould & aaronson 1983 ; mighell 1990 ; smecker - hane , stetson & hesser 1996 ; hurley - keller , mateo & nemec 1998 ; fornax : stetson , hesser & smecker - hane 1998 ; leo i : lee et al ..
Please generate the next two sentences of the article | 1993 , l93 hereinafter ; this paper ) .
other dsph show only a dominant old stellar population in their cmds ( ursa minor : olszewski & aaronson 1985 ; martnez - delgado & aparicio 1999 ; draco : carney & seitzer 1986 ; stetson , vandenbergh & mcclure 1985 ; grillmair et al . |
1,373 | Suppose that you have an abstract for a scientific paper: the power spectrum of heavy ion collisions is investigated by studying initial state fluctuations on top of a smooth hydrodynamic flow .
in particular , the stability of the location of the first minimum of the power spectrum and the dependence of the hydrodynamic response @xmath0 on @xmath1 and on @xmath2 are discussed . in our study
we develop a new green s function method for the analytic hydrodynamic flow by s. gubser and make use of a fully non - linear hydrodynamics code .
we find that there will be no well - defined first minimum of the response for @xmath3 , due to the fact that all minima in that region are found to be sensitive to the location of the initial perturbations .
also , we find that the often proposed form of the hydrodynamical response , that @xmath4 depend quadratically on @xmath1 and linearly on @xmath2 , should not hold once many events have been averaged over . .
And you have already written the first three sentences of the full article: experiments at the relativistic heavy ion collider ( rhic ) and the large hadron collider ( lhc ) have both been able to produce and detect an exotic phase of matter , the quark - gluon plasma ( qgp ) , by colliding massive nuclei at relativistic energies .
the energy densities involved in these collisions are so intense that the hadrons participating in the collisions dissolve into their constituent partons , creating a state of matter in which the color charge is no longer confined . despite the short lifetime of this matter ( on the order of @xmath5 fm / c ) , there is strong evidence that it has time to ( locally ) thermalize and can be described as a nearly perfect fluid .
one can compute the expected abundance of different particle species produced from a thermalized qgp and compare it with the ratios of detected particle species at rhic or lhc ; the results are in good agreement with one another @xcite , @xcite ..
Please generate the next two sentences of the article | another place where hydrodynamics has provided particularly good agreement with heavy ion experiments is with the so - called `` collective flow '' @xcite @xcite .
when two nuclei collide the resulting qgp will be anisotropic in space , because of differences in density distributions inside the individual nuclei , even for central collisions . within hydrodynamics ( implying strong interactions ) , |
1,374 | Suppose that you have an abstract for a scientific paper: we investigate general thermodynamic stability conditions for the superfluid .
this analysis is performed in an extended space of thermodynamic variables containing ( along with the usual thermodynamic coordinates such as pressure and temperature ) superfluid velocity and momentum density .
the stability conditions lead to _ thermodynamic inequalities _ which replace the landau superfluidity criterion at finite temperatures . _
p.l.kapitza institute for physical problems _
+ _ russian academy of sciences , _ + _ kosygin str .
, 2 , 119334 , moscow , russia _ + .
And you have already written the first three sentences of the full article: usually in experiments the vortices destroy superfluidity at velocities far below the landau critical velocity .
this is why the superfluid hydrodynamics equations can be expanded in powers of low velocities and one safely uses the first nontrivial terms of this expansion .
nevertheless , there is a number of experiments ( see @xcite ) where the superfluid flow is investigated in small orifices ..
Please generate the next two sentences of the article | it has been shown that in these circumstances the maximum velocity is a decreasing function of the orifice width and may reach the order of the landau critical velocity if the aperture is small enough .
this means that all thermodynamic quantities of the superfluid become nontrivial functions of the not small superfluid velocity ( _ i.e. , _ it depends not only on the usual thermodynamic coordinates such as pressure and temperature ) . |
1,375 | Suppose that you have an abstract for a scientific paper: we study the principal dirichlet eigenvalue of the operator @xmath0 , on a bounded @xmath1 regular domain @xmath2 . here
@xmath3 , @xmath4 is the fractional laplacian , @xmath5 , and @xmath6 is a bounded @xmath7-dimensional divergence - free vector field in the sobolev space @xmath8 .
we prove that the eigenvalue remains bounded , as @xmath9 , if and only if @xmath6 has non - trivial first integrals in the domain of the quadratic form of @xmath4 for the dirichlet condition . .
And you have already written the first three sentences of the full article: this article is motivated by the following result of berestycki , et al . given in @xcite for the laplacian perturbed by a divergence - free drift in dimensions @xmath10 .
let @xmath11 be a bounded @xmath12 regular open set and let @xmath13 be a bounded @xmath7-dimensional vector field such that @xmath14 on @xmath2 in the sense of distributions ( distr . ) , i.e. @xmath15 for @xmath5 , let ( @xmath16 ) be the principal eigen - pair corresponding to the dirichlet problem for the operator @xmath17 .
theorem 0.3 of @xcite asserts that @xmath18 remains bounded as @xmath9 , if and only if the equation @xmath19 has a solution @xmath20 ( called a first integral of @xmath6 ) , such that @xmath21 and @xmath22.
Please generate the next two sentences of the article | . the result can be interpreted intuitively in the following way : functions @xmath20 satisfying are constant along the flow of the vector field @xmath23 ( see section [ sec : ub ] ) , and the existence of ( non - trivial ) first integrals allows for flow lines that are contained in @xmath2 . on the other hand , if no such @xmath20 exist , then the flow leaves @xmath2 with speed proportional to @xmath24 . adding the laplacian @xmath25 to @xmath26 , or equivalently the brownian motion to the flow , results in a stochastic process whose trajectories gradually depart from the integral curves of @xmath6 , but the general picture is similar :
if nontrivial first integrals exist , then the trajectories may remain in @xmath2 with positive probability during a finite time interval , even as @xmath9 . in this case |
1,376 | Suppose that you have an abstract for a scientific paper: we calculate the casimir energy for scalar fields in interaction with finite - width mirrors , described by nonlocal interaction terms .
these terms , which include quantum effects due to the matter fields inside the mirrors , are approximated by means of a local expansion procedure . as a result of this expansion ,
an effective theory for the vacuum field emerges , which can be written in terms of generalized @xmath0-potentials . we compute explicitly the casimir energy for these potentials and show that , for some particular cases , it is possible to reinterpret them as imposing imperfect dirichlet boundary conditions . .
And you have already written the first three sentences of the full article: casimir forces are a striking manifestation of the zero - point energy of the electromagnetic field in the presence of ` mirrors ' endowed with quite general electromagnetic properties @xcite . in many calculations of the casimir energies and forces
, the presence of the mirrors is modeled by appropriate boundary conditions on the interfaces of the different media , that include macroscopic parameters such as their electric permitivity , magnetic permeability , conductivity , etc .
a first - principles calculation of the casimir energy should consider the microscopic degrees of freedom associated to the mirrors ..
Please generate the next two sentences of the article | this could shed light on some interesting open questions , the role of dissipation on the casimir energy being , perhaps , the most important among them . in a previous paper @xcite
, we considered the casimir effect for scalar and gauge fields interacting with dynamical matter on thin mirrors ( see also ref.@xcite for a concrete model realization ) . |
1,377 | Suppose that you have an abstract for a scientific paper: we consider a phenomenological modification of the pre - big bang scenario using ideas from the resolution of curvature singularities in loop quantum cosmology . we show that non - perturbative loop modifications to the dynamics , arising from the underlying polymer representation , can resolve the graceful exit problem .
the curvature and the dilaton energy stay finite at all times , in both the string and einstein frames . in the string frame
, the dilaton tends to a constant value at late times after the bounce . .
And you have already written the first three sentences of the full article: the problem of graceful exit from the pre- to the post - big bang branch , and the recovery of classical dynamics at late times , has remained a major issue for pre - big bang ( pbb ) models @xcite ( for a review , see @xcite ) .
the equations derived from the low energy effective action of string theory , can not provide a smooth transition between the pre - big bang phase and the standard post - big bang phase of decreasing curvature .
there have been many attempts to solve this problem of overcoming the curvature singularity ..
Please generate the next two sentences of the article | if it is assumed that the curvature at the transition time is small enough to use the low energy equations , then a smooth transition can be achieved either by adding a nonlocal dilaton potential to the action @xcite , or by considering an anisotropic universe dominated by some kind of matter with a suitable equation of state @xcite .
if the curvature is very large , higher - order corrections to the low energy effective action have to be added , which can be derived from the loop expansion and from the @xmath0 expansion @xcite . |
1,378 | Suppose that you have an abstract for a scientific paper: phishing attacks occur because of a failure of computer users to authenticate bob .
the computer user s role , her job , is to authenticate bob .
nobody else can carry out this task .
i researched the ability of browsers to counterfeit the behaviour of installed software .
the objective was to find a signalling strategy which would protect against counterfeiting i.e. phishing attacks .
the research indicates that a user - browser shared secret can not be counterfeited because mallory can not counterfeit what mallory does not know .
after your browser has verified a tls certificate s digital signature the browser should create a two page login wizard .
the first page should display a random educational message , to inform and educate users about the process .
the second page will show the user ( 1 ) the user - browser shared secret , ( 2 ) the verified identity credentials from the tls certificate and ( 3 ) the input fields for the user to enter her login credentials .
the shared secret prevents counterfeiting , prevents phishing .
computer users can now authenticate bob by examining the tls certificate s identity credentials .
the educational messages will communicate to the user , the issues and pitfalls involved . on accepting bob , as bob , the user can enter her login credentials and login . phishing attacks , game theory , applied cryptography , authentication , security protocols , human factors . .
And you have already written the first three sentences of the full article: it was game theory research , seeking screening strategies to prevent the counterfeiting of websites i.e. phishing attacks .
various ways for websites to counterfeit installed software behaviour were studied . in full screen mode , it was found that , browsers can counterfeit almost anything , including blue screens of death and formatting the hard drive . this is discussed in section ii . from an academic point of view
, full screen counterfeiting eliminates several categories of installed software behaviour , as possible anti - counterfeiting solutions ..
Please generate the next two sentences of the article | one category of installed software behaviour was resistant to counterfeiting .
in section iii i present an explanation of this category from the discipline of cryptography and another explanation from the discipline of game theory . |
1,379 | Suppose that you have an abstract for a scientific paper: we analyzed a sample of high and low surface brightness ( hsb and lsb ) disc galaxies and elliptical galaxies to investigate the correlation between the circular velocity ( @xmath0 ) and the central velocity dispersion ( @xmath1 ) .
we better defined the previous @xmath0@xmath2 correlation for hsb and elliptical galaxies , especially at the lower end of the @xmath1 values .
elliptical galaxies with @xmath0 based on dynamical models or directly derived from the h i rotation curves follow the same relation as the hsb galaxies in the @xmath0@xmath2 plane . on the contrary ,
the lsb galaxies follow a different relation , since most of them show either higher @xmath0 ( or lower @xmath1 ) with respect to the hsb galaxies .
this argues against the relevance of baryon collapse in the radial density profile of the dark matter haloes of lsb galaxies .
moreover , if the @xmath0@xmath2 relation is equivalent to one between the mass of the dark matter halo and that of the supermassive black hole , these results suggest that the lsb galaxies host a supermassive black hole with a smaller mass compared to hsb galaxies of equal dark matter halo . on the other hand ,
if the fundamental correlation of smbh mass is with the halo @xmath0 , then lsbs should have larger black hole masses for given bulge @xmath1 .
galaxies : elliptical and lenticular , cd galaxies : fundamental parameters galaxies : kinematics and dynamics galaxies : spirals .
And you have already written the first three sentences of the full article: a possible relation between the central velocity dispersion of the spheroidal component ( @xmath1 ) and the galaxy circular velocity ( @xmath0 ) measured in the flat region of the rotation curve ( rc ) was suggested by whitmore et al .
( 1979 ) . by measuring stellar velocity dispersions and h i line widths for a sample of 19 spiral galaxies they found a a significant decrease in @xmath0@xmath3@xmath1 with increasing bulge - to - disk ratio .
since @xmath1 and @xmath0 probe the potential of the spheroid and dark matter ( dm ) halo , a mean value @xmath0@xmath3@xmath1.
Please generate the next two sentences of the article | @xmath4 implies these components are dynamically separate with the bulge substantially cooler than halo .
gerhard et al . |
1,380 | Suppose that you have an abstract for a scientific paper: we employ unsupervised machine learning techniques to learn latent parameters which best describe states of the two - dimensional ising model and the three - dimensional xy model .
these methods range from principal component analysis to artificial neural network based variational autoencoders .
the states are sampled using a monte - carlo simulation above and below the critical temperature .
we find that the predicted latent parameters correspond to the known order parameters .
the latent representation of the states of the models in question are clustered , which makes it possible to identify phases without prior knowledge of their existence or the underlying hamiltonian .
furthermore , we find that the reconstruction loss function can be used as a universal identifier for phase transitions . .
And you have already written the first three sentences of the full article: inferring macroscopic properties of physical systems from their microscopic description is an ongoing work in many disciplines of physics , like condensed matter , ultra cold atoms or quantum chromo dynamics .
the most drastic changes in the macroscopic properties of a physical system occur at phase transitions , which often involve a symmetry breaking process .
the theory of such phase transitions was formulated by landau as a phenomenological model @xcite and later devised from microscopic principles using the renormalization group @xcite ..
Please generate the next two sentences of the article | one can identify phases by knowledge of an order parameter which is zero in the disordered phase and nonzero in the ordered phase .
whereas in many known models the order parameter can be determined by symmetry considerations of the underlying hamiltonian , there are states of matter where such a parameter can only be defined in a complicated non - local way @xcite . |
1,381 | Suppose that you have an abstract for a scientific paper: we discuss the `` partial '' quantum cloning of the pure two - partite states , when the `` part '' of initial state related to the one qubit is copied only .
the same approach gives the possibility to design the quantum copying machine for the mixed qubit states .
* `` partial '' quantum cloning and quantum cloning of the mixed states * * a.ya.kazakov * + laboratory of quantum information , + st .- petersburg state university of aerospace instrumentation , 67 b.morskaya str . , st .- petersburg , 190000 russia pacs : 03.67 -a , 03.67 dd .
And you have already written the first three sentences of the full article: main laws of quantum mechanics forbids the perfect cloning of the quantum states , see corresponding discussion for the pure states in @xcite , @xcite , and for the mixed states in @xcite .
but it is possible to carry out an approximate copying of the quantum states @xcite .
quantum cloning machines ( qcm ) depend on the conditions accepted at its designing ..
Please generate the next two sentences of the article | they can produce identical copies of the initial state ( symmetric qcm ) , nonidentical copies ( non - symmetric qcm ) , the quality of the copying can be either identical for all states ( universal qcm ) or depend on the state ( state - dependente qcm ) .
detailed discussion of the different variants of qcm and theirs possible applications in quantum cryptography and quantum informatics can be found in @xcite , @xcite . |
1,382 | Suppose that you have an abstract for a scientific paper: we propose a new method to describe a recoiling d - brane that is elastically scattered by closed strings in the non - relativistic region .
we utilize the low - energy effective field theory on the worldvolume of the d - brane , and the velocity of the d - brane is described by the time derivative of the expectation values of the massless scalar fields on the worldvolume .
the effects of the closed strings are represented by a source term for the massless fields in this method .
the momentum conservation condition between the closed strings and the d - brane is derived up to the relative sign of the momentum of the d - brane . plus
0.2pt minus 0.1pt addtoresetequationsection .
And you have already written the first three sentences of the full article: studies of interactions between d - branes and closed strings are quite important from various points of view . the interactions play a crucial role in finding non - trivial relationships between open strings and closed strings such as ads / cft @xcite and recently - proposed open - closed dualities @xcite , for example .
studies of the interactions are also important to analyze the dynamics of the systems of multiple d - branes .
however , almost all analyses of the interactions have been carried out by considering static d - branes , and it is a long - standing problem to describe the back reaction of the d - branes ..
Please generate the next two sentences of the article | a d - brane in the worldsheet description is just a boundary of the worldsheet with dirichlet boundary condition , and the d - brane is treated as an infinitely heavy classical source of closed strings ; the position , or the collective coordinate , of the d - brane is fixed at a point in the target space in the dirichlet direction .
there are several attempts to describe the back reaction of d - branes . |
1,383 | Suppose that you have an abstract for a scientific paper: we consider the motion of a particle in a periodic two dimensional flow perturbed by small ( molecular ) diffusion .
the flow is generated by a divergence free zero mean vector field .
the long time behavior corresponds to the behavior of the homogenized process - that is diffusion process with the constant diffusion matrix ( effective diffusivity ) .
we obtain the asymptotics of the effective diffusivity when the molecular diffusion tends to zero . .
And you have already written the first three sentences of the full article: consider the following stochastic differential equation @xmath0 here @xmath1 is an incompressible periodic vector field , @xmath2 is a 2-dimensional brownian motion , and @xmath3 ( molecular diffusivity ) is a small parameter .
we further assume that the stream function @xmath4 , such that @xmath5 is itself periodic in both variables , that is the integral of @xmath6 over the periodicity cell is zero . for simplicity of notation assume that the period of @xmath7 in each of the variables is equal to one .
it is well known ( see for example @xcite ) , that with @xmath8 fixed , the solution of ( [ e1 ] ) scales like a diffusion process with constant diffusion matrix when time goes to infinity ..
Please generate the next two sentences of the article | more precisely , there exists the limit , called the effective diffusivity , @xmath9 where @xmath10 and @xmath11 are the coordinates and @xmath12 is the initial distribution of the process @xmath13 , which we can take to be an arbitrary measure with compact support .
the measure on @xmath14 , { \mbox { \bbc r}}^2)$ ] , induced by the process @xmath15 , converges weakly , when @xmath16 , to the measure induced by the diffusion process with constant matrix @xmath17 . |
1,384 | Suppose that you have an abstract for a scientific paper: both high precision ccd photometric and h@xmath0 line studies are presented for an overcontact binary asas j082243 + 1927.0 . the light curve exhibits a total eclipse at secondary minima along with an * oconnell * effect . the light curve was modeled using the wilson devinney code and the best solution provides the mass ratio q @xmath1 0.106 and fill - out factor f @xmath1 72% .
these parameters indicate that the system is a low mass ratio overcontact binary with a high degree of geometrical contact .
the h@xmath0 line equivalent width varied at different phases and it is found that the line is possibly filled - in at secondary minima . from a small sample of overcontact binaries , we found a correlation between the orbital period and h@xmath0 line equivalent width of the primary component .
based on a sample of high filling factor and low mass ratio contact binaries , a mass ratio cut - off is observed at q@xmath2 = 0.085 in mass - ratio period plane . it was observed that below q@xmath2 @xmath3 0.085 , period decreases with an increase in q and above it , period increases as the mass ratio increases .
interestingly , the observed mass ratio cut - off value lies close to the critical mass ratio range as predicted in the literature .
the observational evidence of the cut - off of the mass ratio and its variation with orbital period * are * discussed in terms of mass transfer and angular momentum loss . based on the results
, we suggest that , asas j082243 + 1927.0 is at the verge of merger , eventually forming a fast rotating star .
[ firstpage ] binaries : close binaries ; binaries eclipsing ; stars : individual ( asas j082243 + 1927.0 ) .
And you have already written the first three sentences of the full article: w ursae majoris ( w uma ) variables are eclipsing overcontact binaries with orbital periods ranging from 0.2 1.0 day .
these systems consist of main sequence stars with spectral a - k type sharing a common convective envelope due to filled roche lobes . in some cases
these binaries host o or b spectral type component surrounded with a common radiative envelope , whose true physical understanding is still lacking . in low mass overcontact binaries , it has been argued that the secondary component is oversized with respect to its expected zams radius and at an advanced evolutionary stage ( stepien 2006a ) ..
Please generate the next two sentences of the article | the role of common envelope is to distribute the energy uniformly over the surface of the stars ( lucy 1968 ) , having similar brightness with a few percent difference exhibiting chromospheric activity ( vilhu & walter 1987 ) .
the overcontact binaries are important astrophysical sources as they help to understand the underlying mechanism of the merging process ( eg . |
1,385 | Suppose that you have an abstract for a scientific paper: gamma - ray spectra from cosmic - ray proton and electron interactions with dense gas clouds have been calculated using a monte carlo event simulation code , geant4 .
such clouds are postulated as a possible form of baryonic dark matter in the universe .
the simulation fully tracks the cascade and transport processes which are important in a dense medium , and the resulting gamma - ray spectra are computed as a function of cloud column - density .
these calculations are used for predicting the galactic diffuse gamma - ray spectrum which may be contributed by baryonic dark matter ; the results are compared with data from the egret instrument , and used to constrain the fraction of galactic dark matter which may be in the form of dense gas clouds . in agreement with previous authors ,
we find useful constraints on the fraction of galactic dark matter which may be in the form of low column - density clouds ( @xmath0 ) .
however , this fraction rises steeply in the region @xmath1 , and for @xmath2 we find that baryonic dark matter models are virtually unconstrained by the existing gamma - ray data . .
And you have already written the first three sentences of the full article: the nature of dark matter remains one of the outstanding questions of modern astrophysics .
the success of the cold dark matter cosmological model ( albeit with `` dark energy '' now required : @xmath3cdm ) argues strongly for a major component of the dark matter being in the form of an elementary particle .
however , the inventory of baryons which we can observe locally falls far short of the total inferred from observations of the cosmic microwave background fluctuations @xcite , leaving open the possibility that there may be a significant baryonic component of dark matter ..
Please generate the next two sentences of the article | furthermore , although @xmath3cdm is very successful in describing the growth of structure in the universe on large scales , we still lack a direct detection of any of the candidate dark matter particles . lacking this decisive piece of observational evidence , some authors have proposed models which include a large component of baryonic dark matter . in particular
there have been many papers dealing with the possibility that cold , self - gravitating molecular clouds constitute a major component of the dark matter @xcite . a variety of different forms , including isolated , clustered , and fractal , |
1,386 | Suppose that you have an abstract for a scientific paper: we compare the behaviour of a new 2d aqueous colloidal model system with a simple numerical treatment . to first order
the attractive interaction between the colloids induced by an in - plane rotating ac electric field is dipolar , while the charge stablisation leads to a shorter ranged , yukawa - like repulsion . in the crystal - like ` rafts ' formed at sufficient field strengths , we find quantitative agreement between experiment and monte carlo simulation , except in the case of strongly interacting systems , where the well depth of the effective potential exceeds 250 times the thermal energy .
the ` lattice constant ' of the crystal - like raft is located approximately at the minimum of the effective potential , resulting from the sum of the yukawa and dipolar interactions .
the experimental system has display applications , owing to the possibility of tuning the lattice spacing with the external electric field .
limitations in the applied field strength and relative range of the electrostatic interactions of the particles results in a reduction of tunable lattice spacing for small and large particles respectively . the optimal particle size for maximising the lattice spacing tunability
was found to be around 1000 nm . .
And you have already written the first three sentences of the full article: colloidal suspensions present the possibility to develop novel materials via self - assembly . of particular interest are colloidal crystals , whose optical properties can generate iridescent colours , and provide a means by which photonic crystals may be produced@xcite , while further applications range from lasers @xcite to display devices @xcite , with recent advances demonstrating tunable colours through control of lattice spacing with an external field @xcite .
further to the practical importance of colloidal crystals , their well - defined thermodynamic temperature allows colloidal dispersions to be viewed as mesoscopic ` model atoms ' @xcite .
recently , the ability to tune the colloid - colloid interactions has led to the observation of a wide variety of structures @xcite ..
Please generate the next two sentences of the article | of particular interest here , to first order ac electric fields can induce dipolar interactions between the colloidal particles , leading to anisotropic interparticle potentials and exotic crystal structures , some of which are not observed in atomic and molecular systems @xcite , while external control of the colloid - colloid interactions allows direct observation of phase transitions @xcite .
furthermore , direct microscopic observation at the single - particle level allows an unprecedented level of detail to be accessed @xcite , opening the possibility of tackling long - standing problems in condensed matter , such as freezing @xcite . |
1,387 | Suppose that you have an abstract for a scientific paper: we consider the problem of predicting a real random variable from a functional explanatory variable .
the problem is attacked by mean of nonparametric kernel approach which has been recently adapted to this functional context .
we derive theoretical results by giving a deep asymptotic study of the behaviour of the estimate , including mean squared convergence ( with rates and precise evaluation of the constant terms ) as well as asymptotic distribution .
practical use of these results are relying on the ability to estimate these constants .
some perspectives in this direction are discussed .
in particular a functional version of wild bootstrapping ideas is proposed and used both on simulated and real functional datasets .
* key words : * asymptotic normality , functional data , nonparametric model , quadratic error , regression , wild functional bootstrap . .
And you have already written the first three sentences of the full article: functional data are more and more frequently involved in statistical problems . developping statistical methods in this special framework
has been popularized during the last few years , particularly with the monograph by ramsay & silverman ( 2005 ) .
more recently , new developments have been carried out in order to propose nonparametric statistical methods for dealing with such functional data ( see ferraty & vieu , 2006 , for large discussion and references ) ..
Please generate the next two sentences of the article | these methods are also called doubly infinite dimensional ( see ferraty & vieu , 2003 )
. indeed these methods deal with infinite - dimensional ( i.e. functional ) data and with a statistical model which depends on an infinite - dimensional unknown object ( i.e. a nonparametric model ) . |
1,388 | Suppose that you have an abstract for a scientific paper: we calculate the casimir - lifshitz pressure in a system consisting of two different 1d dielectric lamellar gratings having two different temperatures and immersed in an environment having a third temperature .
the calculation of the pressure is based on the knowledge of the scattering operators , deduced using the fourier modal method .
the behavior of the pressure is characterized in detail as a function of the three temperatures of the system as well as the geometrical parameters of the two gratings .
we show that the interplay between non - equilibrium effects and geometrical periodicity offers a rich scenario for the manipulation of the force .
in particular , we find regimes where the force can be strongly reduced for large ranges of temperatures .
moreover , a repulsive pressure can be obtained , whose features can be tuned by controlling the degrees of freedom of the system . remarkably , the transition distance between attraction and repulsion can be decreased with respect to the case of two slabs , implying an experimental interest for the observation of repulsion . .
And you have already written the first three sentences of the full article: casimir - lifshitz force in an interaction originating from the fluctuations of the electromagnetic field and existing between any couple of polarizable bodies .
it was first theoretically derived by casimir in 1948 @xcite in the idealized configuration of two perfectly conducting parallel plates at zero temperature .
later , lifshitz and collaborators generalized the calculation to the case of bodies having arbitrary optical properties and of finite temperature @xcite ..
Please generate the next two sentences of the article | the casimir - lifshitz interaction , experimentally verified for several different geometries @xcite , results from two contributions , one originating from vacuum fluctuations and present also at zero temperature , the other one from purely thermal fluctuations . the latter becomes relevant when the distance separating the bodies is larger than the thermal wavelength @xmath0 , of the order of @xmath1 m at ambient temperature .
this explains why it has been only very recently experimentally observed at thermal equilibrium @xcite . |
1,389 | Suppose that you have an abstract for a scientific paper: an offline signature - based fuzzy vault ( osfv ) is a bio - cryptographic implementation that uses handwritten signature images as biometrics instead of traditional passwords to secure private cryptographic keys . having a reliable osfv implementation is the first step towards automating financial and legal authentication processes , as it provides greater security of confidential documents by means of the embedded handwritten signatures .
the authors have recently proposed the first osfv implementation which is reviewed in this paper . in this system ,
a machine learning approach based on the dissimilarity representation concept is employed to select a reliable feature representation adapted for the fuzzy vault scheme .
some variants of this system are proposed for enhanced accuracy and security . in particular , a new method that adapts user key size is presented .
performance of proposed methods are compared using the brazilian pucpr and gpds signature databases and results indicate that the key - size adaptation method achieves a good compromise between security and accuracy . while average system entropy is increased from 45-bits to about 51-bits , the aer ( average error rate ) is decreased by about 21% . .
And you have already written the first three sentences of the full article: automation of financial and legal processes requires enforcement of confidentiality and integrity of transactions . for practical integration with the existing manual systems , such enforcement should be transparent to users .
for instance , a person continually signs paper - based documents ( e.g. , bank checks ) by hand , while his embedded handwritten signature images are used to secure the digitized version of the signed documents .
such scenario can be realizable using biometric cryptosystems ( also known as bio - cryptographic systems @xcite ) by means of the offline handwritten signature images . in bio - cryptography , biometric signals like fingerprints , iris , face or signature images , etc ..
Please generate the next two sentences of the article | , secure private keys within cryptography schemes like digital signatures and encryption .
biometric samples provide a more trusted identification tool when compared to simple passwords . |
1,390 | Suppose that you have an abstract for a scientific paper: although the quality of quantum bits ( qubits ) and quantum gates has been steadily improving , the available quantity of qubits has increased quite slowly . to address this important issue in quantum computing
, we have demonstrated arbitrary single qubit gates based on targeted phase shifts , an approach that can be applied to atom , ion or other atom - like systems .
these gates are highly insensitive to addressing beam imperfections and have little crosstalk , allowing for a dramatic scaling up of qubit number .
we have performed gates in series on 48 individually targeted sites in a 40% full @xmath0 3d array created by an optical lattice . using randomized benchmarking
, we demonstrate an average gate fidelity of 0.9962(16 ) , with an average crosstalk fidelity of 0.9979(2 ) .
pacs numbers : : the performance of isolated quantum gates has recently been improved for several types of qubits , including trapped ions @xcite , josephson junctions @xcite , quantum dots @xcite , and neutral atoms @xcite .
single qubit gate errors now approach or , in the case of ions , surpass the commonly accepted error - threshold @xcite ( error per gate @xmath1 ) , for fault - tolerant quantum computation @xcite .
it remains a challenge in all these systems to execute targeted gates on many qubits with fidelities comparable to those for isolated qubits @xcite .
neutral atom and ion experiments have to date demonstrated the most qubits in the same system , 50 and 18 respectively @xcite .
the highest fidelity gates in these systems are based on microwave transitions , but addressing schemes typically depend on either addressing light beams @xcite which are difficult to make as stable as microwaves , or magnetic field gradients @xcite which limit the number of addressed qubits . in this report
, we present a way to induce phase shifts on atoms at targeted sites in a @xmath2 optical lattice that is highly insensitive to addressing laser beam fluctuations .
we further show how to convert targeted....
And you have already written the first three sentences of the full article: this work was supported by the us national science foundation grant phy-1520976 .
inspection of fig .
1 ( b ) shows that there are two phase shift extrema as a function of @xmath9 ..
Please generate the next two sentences of the article | the one we do not use , between the spectator and line resonances , is less sensitive to detuning , but it would increase the rate of unintentional transfer out of the qubit basis . this is partly because there are many more spectator atoms than targets ; the small amount of off - resonant transfer would get multiplied by a much larger number .
in addition , there can be atoms that see a fraction of the intensity that most line atoms see , due to misalignment of beams relative to the lattice or beam profile imperfections ; this can put their resonances closer to the phase shifting microwaves . |
1,391 | Suppose that you have an abstract for a scientific paper: using three coupled harmonic oscillators , we have recently proposed [ arxiv:1007.4338 ] an alternative approach for quantum factorization of an integer .
however , the probability of obtaining the factors becomes low when this number is large .
here , we circumvent this limitation by using a new iterative method which can efficiently increase the probability of finding the factors .
we show that the factors of a number can be obtained , in linear time , with a high probability .
this amplitude - amplification method can be applied to search problems .
this implies that search - based problems including np - complete problems can be exponentially sped up .
in addition , we generalize the method of amplitude amplification by using a system of coupled harmonic oscillators .
this can be used for solving a system of linear or nonlinear functions with integer inputs subject to a number of constraints .
the total number of oscillators in the system is equal to the number of integer variables in the functions plus the number of constraints . .
And you have already written the first three sentences of the full article: quantum computing based on qubits has attracted considerable attention ( see , e.g. , @xcite ) .
there are several candidates to realize quantum computers , such as using nuclear spins in molecules , photons , trapped ions , superconducting circuit and quantum dots ( see , e.g. , @xcite ) .
however , it is still a great challenge to build a large - scale quantum computer ..
Please generate the next two sentences of the article | quantum computers can significantly outperform classical computers in doing some specific tasks @xcite .
for example , two important quantum algorithms are shor s @xcite and grover s @xcite . |
1,392 | Suppose that you have an abstract for a scientific paper: we discuss how much we can probe the effective number of neutrino species @xmath0 with cosmic microwave background alone . using the data of wmap , acbar , cbi and boomerang experiments , we obtain a constraint on the effective number of neutrino species as @xmath1 at 95%c.l . for a power - law @xmath2cdm flat universe model .
the limit is improved to be @xmath3 at 95%c.l .
if we assume that the baryon density , @xmath0 and the helium abundance are related by the big bang nucleosynthesis theory .
we also provide a forecast for the planck experiment using a markov chain monte carlo approach .
in addition to constraining @xmath0 , we investigate how the big bang nucleosynthesis relation affects the estimation for these parameters and other cosmological parameters .
july 2008 + .5 in * probing the effective number of neutrino species with cosmic microwave background * .45 in kazuhide ichikawa@xmath4 , toyokazu sekiguchi@xmath5 , and tomo takahashi@xmath6 .45 in _
@xmath5 institute for cosmic ray research , university of tokyo , kashiwa 277 - 8582 , japan + @xmath7 department of physics and astronomy , university college london , gower street , london , wc1e 6bt , u.k .
+ @xmath6 department of physics , saga university , saga 840 - 8502 , japan _
.4 in .
And you have already written the first three sentences of the full article: cosmology is now becoming a precision science , and cosmological observations can give us a lot of information for our understanding of the universe .
moreover , the interplay between cosmology and particle physics in various contexts has also been discussed vigorously .
one of such examples is the effective number of neutrino species @xmath0 . although collider experiments such as lep have measured the number of light active neutrino types to be @xmath8 @xcite , it is important to cross - check this value because cosmological measurements may lead to different value.
Please generate the next two sentences of the article | . this could be due to an extra radiation component which is predicted by some models of particle physics such as sterile neutrinos ( see ref .
@xcite and references therein ) , or due to incomplete thermalization of neutrinos in the low - scale reheating universe in which the reheating temperature @xmath9 can be as low as @xmath10mev and @xmath0 is predicted to be less than three @xcite . |
1,393 | Suppose that you have an abstract for a scientific paper: the information in an individual finite object ( like a binary string ) is commonly measured by its kolmogorov complexity .
one can divide that information into two parts : the information accounting for the useful regularity present in the object and the information accounting for the remaining accidental information .
there can be several ways ( model classes ) in which the regularity is expressed .
kolmogorov has proposed the model class of finite sets , generalized later to computable probability mass functions .
the resulting theory , known as algorithmic statistics , analyzes the algorithmic sufficient statistic when the statistic is restricted to the given model class .
however , the most general way to proceed is perhaps to express the useful information as a recursive function .
the resulting measure has been called the `` sophistication '' of the object .
we develop the theory of recursive functions statistic , the maximum and minimum value , the existence of absolutely nonstochastic objects ( that have maximal sophistication all the information in them is meaningful and there is no residual randomness ) , determine its relation with the more restricted model classes of finite sets , and computable probability distributions , in particular with respect to the algorithmic ( kolmogorov ) minimal sufficient statistic , the relation to the halting problem and further algorithmic properties .
_ index terms_ constrained best - fit model selection , computability , lossy compression , minimal sufficient statistic , non - probabilistic statistics , kolmogorov complexity , kolmogorov structure function , sufficient statistic , sophistication .
And you have already written the first three sentences of the full article: the information contained by an individual finite object ( like a finite binary string ) is objectively measured by its kolmogorov complexity the length of the shortest binary program that computes the object .
such a shortest program contains no redundancy : every bit is information ; but is it meaningful information ? if we flip a fair coin to obtain a finite binary string , then with overwhelming probability that string constitutes its own shortest program .
however , also with overwhelming probability all the bits in the string are meaningless information , random noise . on the other hand ,.
Please generate the next two sentences of the article | let an object @xmath0 be a sequence of observations of heavenly bodies .
then @xmath0 can be described by the binary string @xmath1 , where @xmath2 is the description of the laws of gravity , and the observational parameter setting , while @xmath3 is the data - to - model code accounting for the ( presumably gaussian ) measurement error in the data . this way we can divide the information in @xmath0 into meaningful information @xmath2 and data - to - model information @xmath3 . |
1,394 | Suppose that you have an abstract for a scientific paper: the two - kaon interferometry at rhic is studied in a multi - phase transport model .
similar to the pion case , we find strong space - time correlation at freeze - out for the kaon emission source , which results in a large positive @xmath0 term and tends to reduce the @xmath1 ratio .
unlike the pion case , the source radii for kaons determined from the emission function are close to the radius parameters extracted from a gaussian fit to the correlation function . . .
And you have already written the first three sentences of the full article: particle interferometry based on the hanbury - brown twiss ( hbt ) effect has been used extensively in heavy ion collisions to extract the information on the emission source of particles @xcite . in particular , the long emission time as a result of the phase transition from the quark - gluon plasma to hadronic matter in relativistic heavy ion collisions may lead to an emission source which has a much larger radius in the direction of the total transverse momentum of detected two particles ( @xmath2 ) than that perpendicular to both this direction and the beam direction ( @xmath3 ) @xcite . since the quark - gluon plasma is expected to be formed in heavy ion collisions at rhic , it is surprising to find that the extracted ratio @xmath4 from a gaussian fit to the measured two - pion correlation function in au+au collisions at @xmath5 gev is close to one @xcite , very different from predictions of hydrodynamical models @xcite .
since particle interferometry probes the phase - space distributions of particles at freeze - out , it is natural to apply transport models to hbt .
the reason is that particle freeze - out is dynamically generated in transport models when the mean - free - path exceeds the system size at later stage of expansion , whereas freeze - out has to be imposed in hydrodynamical models . using a multi - phase transport ( ampt ) model , we have found that the small pion @xmath1 ratio could be due to a large and positive space - time correlation in the emission source @xcite ..
Please generate the next two sentences of the article | furthermore , the pion source at freeze - out is highly non - gaussian , leading to much larger pion source radii than the radius parameters from a gaussian fit to the three - dimensional correlation function . in this study
, we extend the work of ref.@xcite by studying the kaon interferometry in central au+au collisions at rhic energies . using the ampt model , |
1,395 | Suppose that you have an abstract for a scientific paper: xml and xml schema are widely used in different domains for the definition of standards that enhance the interoperability between parts exchanging information through the internet . the size and complexity of some standards , and their associated schemas ,
have been growing with time as new use case scenarios and data models are added to them . the common approach to deal with the complexity of producing xml processing code based on these schemas
is the use of xml data binding generators .
unfortunately , these tools do not always produce code that fits the limitations of resource - constrained devices , such as mobile phones , in the presence of large schemas .
in this paper we present _ instance - based xml data binding _ , an approach to produce compact application - specific xml processing code for mobile devices .
the approach utilises information extracted from a set of xml documents about how the application make use of the schemas .
[ languages and system , standards ] .
And you have already written the first three sentences of the full article: extensible markup language ( xml ) has reached a great success in the internet era .
xml documents are similar to html documents , but do not restrict users to a single vocabulary , which offers a great deal of flexibility to represent information . to define the structure of documents within a certain vocabulary , schema languages such as _ document type definition _
( dtd ) or _ xml schema _ are used ..
Please generate the next two sentences of the article | xml has been adopted as the most common form of encoding information exchanged by web services @xcite . @xcite
attribute this success to two reasons . |
1,396 | Suppose that you have an abstract for a scientific paper: we discuss how embeddings in connection with the campbell - magaard ( cm ) theorem can have a physical interpretation .
we show that any embedding whose local existence is guaranteed by the cm theorem can be viewed as a result of the dynamical evolution of initial data given in a four - dimensional spacelike hypersurface . by using the cm theorem
, we establish that for any analytic spacetime , there exist appropriate initial data whose cauchy development is a five - dimensional vacuum space into which the spacetime is locally embedded .
we shall see also that the spacetime embedded is cauchy stable with respect these the initial data .
the development of the braneworld scenario @xcite , in which our ordinary spacetime is viewed as a hypersurface of a higher - dimensional space , has greatly contributed to increase recent interest on embeddings theorems .
the so - called non - compact kaluza - klein ( nkk ) models @xcite have also motivated the study of embedding problems of the spacetime . in this context ,
the campbell - magaard ( cm ) theorem @xcite and its variants @xcite are of special interest when the embedding spaces possess only one extra dimension as is the case of the randall - sundrum braneworld scenario @xcite and the nkk models @xcite .
the cm theorem ensures the existence of local and analytic isometric embedding of any @xmath0-dimensional analytic manifold @xmath1 into a ricci - flat @xmath2-dimensional space .
it can be stated as follow : given a @xmath0-dimensional analytic space @xmath3 , where @xmath4 stands for the metric , for any point @xmath5 there exists a vacuum solution of einstein equations in @xmath2-dimensions into which a neighborhood of @xmath6 in @xmath1 can be embedded .
the cm theorem is valid for any analytic metric @xmath4 irrespective of its signature and for dimension @xmath7 .
however , having in mind applications to physics , we shall consider @xmath8 , throughout the paper , and assume that the metric is lorentzian .
the cm theorem is....
And you have already written the first three sentences of the full article: consider the lorentzian metric of the five - dimensional space written in a gaussian form @xmath9 where @xmath10 , and latin indices run from @xmath11 to @xmath12 while the greek ones go from @xmath11 to @xmath13 by splitting the vacuum einstein equations in terms of the extrinsic and intrinsic curvatures of the slices @xmath14 , it can be shown that the equations have the following structure : @xmath15 where @xmath16 are analytic functions of their arguments , @xmath17 is the covariant derivative with respect to the induced metric @xmath18 ; @xmath19 and @xmath20 denote , respectively , the scalar curvature and the extrinsic curvature of the hypersurface @xmath21 and @xmath22 . recall that in the coordinates adopted the extrinsic curvature assumes the simple form : @xmath23 it is well known that , owing to the bianchi identities , the second and third equations need to be imposed only on the hypersurface , since they are propagated by the first one . in this sense , it is said that the einstein equations consist of the _ dynamical _ equation ( [ dyn ] ) plus _ constraint equations _
( [ c1 ] ) and ( [ c2 ] ) for @xmath20 and @xmath24 .
let now consider the hypersurface @xmath25 according to the cauchy - kowalewski theorem , for any point in this hypersurface , say the origin , there is an open set in five dimensions containing that point , where the equation ( [ dyn ] ) always has a unique analytic solution @xmath26 provided that the following analytic initial conditions are specified : @xmath27 from the perspective of the embedding problem these initial conditions represent , respectively , the metric and the extrinsic curvature of the hypersurface @xmath28 , whereas the solution of equation ( [ dyn ] ) gives the metric of the @xmath29dimensional space . thus , if there is a solution for the constraint equations for any given metric @xmath30 , then the theorem is proved , since the solution found @xmath31 substituted in ( [ hds2 ] ) will give rise to a metric that satisfies the vacuum einstein....
Please generate the next two sentences of the article | clearly , the embedding map is then given by the equation @xmath33 .
it turns out , as magaard has proved @xcite , that the constraint equations always have a solution . |
1,397 | Suppose that you have an abstract for a scientific paper: the strong spectral features near 2.2 @xmath0 m in early - type galaxies remain relatively unexplored . yet , they open a tightly focused window on the coolest giant stars in these galaxies a window that can be used to explore both age and metallicity effects . here , new measurements of k - band spectral features are presented for eleven early - type galaxies in the nearby fornax galaxy cluster .
based on these measurements , the following conclusions have been reached : ( 1 ) in galaxies with no signatures of a young stellar component , the k - band index is highly correlated with both the optical metallicity indicator and the central velocity dispersion @xmath1 ; ( 2 ) in the same galaxies , the k - band fe features saturate in galaxies with @xmath2 @xmath3 while ( and ) continues to increase ; ( 3 ) [ si / fe ] ( and possibly [ na / fe ] ) is larger in all observed fornax galaxies than in galactic open clusters with near - solar metallicity ; ( 4 ) in various near - ir diagnostic diagrams , galaxies with signatures of a young stellar component ( strong , weak ) are clearly separated from galaxies with purely old stellar populations ; furthermore , this separation is consistent with the presence of an increased number of m - giant stars ( most likely to be thermally pulsating agb stars ) ; ( 5 ) the near - ir vs. @xmath1 or vs. @xmath1 diagrams discussed here seem as efficient for detecting putatively young stellar components in early - type galaxies as the more commonly used age / metallicity diagnostic plots using optical indices ( e.g h@xmath4 vs. ) .
the combination of these spectral indices near 2.2 @xmath0 m with high _ spatial _ resolution spectroscopy from ground - based or space - based observatories promises to provide new insights into the nature of stellar populations in the central regions of distant early - type galaxies . .
And you have already written the first three sentences of the full article: understanding the stellar content of early - type galaxies is fundamental to understanding their star formation and chemical evolution history .
most early - type galaxies are too distant to resolve their individual stars with current technology , rendering the direct study of their stellar populations impossible .
thus , their stellar populations must be studied using indirect methods . in recent decades.
Please generate the next two sentences of the article | , significant effort has gone into trying to better constrain the stellar contents for early - type galaxies using optical spectroscopic data .
the most commonly studied features have been ca i h and k 0.38 @xmath0 m , h@xmath4 , mgb 0.52 @xmath0 m , fe @xmath0 m 0.53 , na 0.82 @xmath0 m , and cat 0.86 @xmath0 m . |
1,398 | Suppose that you have an abstract for a scientific paper: we present photometry and spectra of the large kuiper belt object 2007 or10 .
the data show significant near - infrared absorption features due to water ice .
while most objects in the kuiper belt with water ice absorption this prominent have the optically neutral colors of water ice , 2007 or10 is among the reddest kuiper belt objects known .
one other large kuiper belt object
quaoar has similar red coloring and water ice absorption , and it is hypothesized that the red coloration of this object is due to irradiation of the small amounts of methane able to be retained on quaoar .
2007 or10 , though warmer than quaoar , is in a similar volatile retention because it is sufficiently larger that its stronger gravity can still retain methane .
we propose , therefore , that the red coloration on 2007 or10 is also caused by the retention of small amounts of methane .
positive detection will require spectra of methane on 2007 or10 will require spectra with higher signal - to - noise .
models for volatile retention on kuiper belt objects appear to continue to do an excellent job reproducing all of the available observations . .
And you have already written the first three sentences of the full article: the large majority of kuiper belt objects ( kbos ) contain no detectable volatile ices on their surfaces , but a small number of the largest objects have been found to have signatures of ch@xmath0 , co , or n@xmath1 , all ices with high vapor pressures at kuiper belt temperatures .
after the discovery of volatiles on the surfaces of eris @xcite , makemake @xcite , and sedna , @xcite proposed a simple method for assessing the possibility of volatile retention on kbos .
for each relevant ice , they compared the volatile loss due to jean s escape the slowest of many possible escape mechanisms to the total volatile inventory of the object and divided the kuiper belt into objects which could and could not have retained that ice over the age of the solar system ..
Please generate the next two sentences of the article | only a handful of objects are massive enough or cold enough to be able to retain volatiles .
their model provided a compelling explanation of the low abundance of n@xmath1 on makemake @xcite , which is smaller than pluto and eris , and was also used to successfully predict the presence of methane on quaoar @xcite . to date , the volatile retention model has been completely successful predicting which objects will and which will not have detectable surface volatiles , with the unique exception being the large kbo haumea , which is the parent body of the only collisional family known in the kuiper belt @xcite and clearly had an unusual history . |
1,399 | Suppose that you have an abstract for a scientific paper: we report on the march - april 1997 bepposax observations of aql x-1 , the first to monitor the evolution of the spectral and time variability properties of a neutron star soft x
ray transient from the outburst decay to quiescence .
we observed a fast x ray flux decay , which brought the source luminosity from @xmath0 to @xmath1 in less than 10 days .
the x ray spectrum showed a power law high energy tail with photon index @xmath2 which hardened to @xmath3 as the source reached quiescence .
these observations , together with the detection by rossixte of a periodicity of a few milliseconds during an x ray burst , likely indicate that the rapid flux decay is caused by the onset of the propeller effect arising from the very fast rotation of the neutron star magnetosphere . the x ray luminosity and hard spectrum that characterise the quiescent emission can be consistently interpreted as shock emission by a turned - on rotation - powered pulsar . .
And you have already written the first three sentences of the full article: soft x ray transients ( sxrts ) , when in outburst , show properties similar to those of persistent low mass x ray binaries containing a neutron star ( lmxrbs ; white et al .
1984 ; tanaka & shibazaki 1996 ; campana et al . 1998 ) . the large variations in the accretion rate that are characteristic of sxrts allow the investigation of a variety of regimes for the neutron stars in these systems which are inaccessible to persistent lmxrbs .
while it is clear that , when in outbursts , sxrts are powered by accretion , the origin of the low luminosity x .
Please generate the next two sentences of the article | ray emission that has been detected in the quiescent state of several sxrts is still unclear .
an interesting possibility is that a millisecond radio pulsar ( msp ) turns on in the quiescent state of sxrts ( stella et al . |
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