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1003.0672 | c | if some post - inflationary physics involves the spontaneous breaking of an exact @xmath3 symmetry with @xmath201 , then the ordering of these scalar fields may provide a secondary contribution to primordial perturbations . current constraints allow up to @xmath5 of the power in primordial perturbations to be due to so... | we calculate the bispectrum that arises in models of self - ordered scalar fields . the bispectrum is largest for triangles that are aligned ( have edges ) as opposed to the local - model bispectrum , which peaks for squeezed triangles ( ) , and the equilateral bispectrum , which peaks at . | the universe may harbor relics of the post - inflationary epoch in the form of a network of self - ordered scalar fields . such fossils , while consistent with current cosmological data at trace levels , may leave too weak an imprint on the cosmic microwave background and the large - scale distribution of matter to all... |
hep-ph0104049 | i | after many years of fruitful operation , the lep experiments have been closed down and the lep2 data analysis is approaching its final stage . in the area of @xmath2-pair physics the experimental precision is very high : in order to match it , theoretical calculations must include not only tree - level four - fermion b... | the version 1.51 of the monte carlo ( mc ) program koralw for all processes is presented . may be modified in order to fit them to experimental data . another important new feature is the possibility of including complete corrections to double - resonant-pair component - processes in addition to all background ( non- )... | the version 1.51 of the monte carlo ( mc ) program koralw for all processes is presented . the most important change from the previous version 1.42 is the facility for writing mc events on the mass storage device and reprocessing them later on . in the reprocessing parameters of the standard model may be modified in or... |
1410.3422 | i | the wiretap channel model @xmath0 was introduced by wyner in 1975 @xcite . in this model , there are two receivers @xmath1 and a single transmitter @xmath2 . the transmitter aims at sending messages to receiver 1 through a communication channel @xmath3 . the information sent from @xmath2 to @xmath4 is also received by ... | explicit capacity - achieving schemes for various models of the wiretap channel have received considerable attention in recent literature . in this paper research supported in part by nsf grant ccf1217245 ] department of ece and institute for systems research , university of maryland , college park , md 20742 , and... | the wiretap channel model of wyner is one of the first communication models with both reliability and security constraints . explicit capacity - achieving schemes for various models of the wiretap channel have received considerable attention in recent literature . in this paper , we address the original version of this... |
astro-ph9512143 | i | a few years ago , we started a project to determine ages , metallicities , and reddenings of distinct stellar populations employing a newly developed technique of simultaneous multi - colour isochrone fitting ( roberts 1996 , grebel et al . when applying this technique to the young cluster ngc 330 in the small magellan... | the young smc cluster ngc 330 contains a number of blue stars that lie above the main - sequence turnoff found from our isochrone fitting and below the position of the blue supergiants . these stars lie in the rapidly traversed post main - sequence gap , similar to the unexpected concentration found by fitzpatrick & ga... | the young smc cluster ngc 330 contains a number of blue stars that lie above the main - sequence turnoff found from our isochrone fitting and below the position of the blue supergiants . we used our own , new spectroscopy and published data on these stars to investigate their possible nature . problems in interpreting ... |
1103.4591 | i | this article is part of a larger program , which consists in devising and quantitatively analyzing numerical methods to approximate effective coefficients in stochastic homogenization of linear elliptic equations . more precisely we tackle here the case of a discrete elliptic equation with independent and identically d... | this article is devoted to the analysis of a monte - carlo method to approximate effective coefficients in stochastic homogenization of discrete elliptic equations . we consider the case of independent and identically distributed coefficients , and adopt the point of view of the random walk in a random environment . gi... | this article is devoted to the analysis of a monte - carlo method to approximate effective coefficients in stochastic homogenization of discrete elliptic equations . we consider the case of independent and identically distributed coefficients , and adopt the point of view of the random walk in a random environment . gi... |
math0508330 | i | this paper addresses reduction theory for discrete mechanical systems with abelian symmetry groups and its relation to variational integration . to establish the setting of the problem , a few aspects of the continuous theory are first recalled ( see @xcite for general background ) . * continuous reduction theory . ... | this paper develops the theory of abelian routh reduction for discrete mechanical systems and applies it to the variational integration of mechanical systems with abelian symmetry . these reduced methods allow the direct simulation of dynamical features such as relative equilibria and relative periodic orbits that can ... | this paper develops the theory of abelian routh reduction for discrete mechanical systems and applies it to the variational integration of mechanical systems with abelian symmetry . the reduction of variational runge - kutta discretizations is considered , as well as the extent to which symmetry reduction and discretiz... |
hep-th0006147 | c | in this paper we have described the rational map ansatz applied to skyrmions on a @xmath0-sphere of radius @xmath2 . we have calculated the energy @xmath141 of a skyrmion as a function of @xmath2 for baryon number @xmath352 and found the following behaviour : for small @xmath2 the energy @xmath141 scales like @xmath57 ... | this paper discusses multi - skyrmions on the-sphere with variable radius using the rational map ansatz . for baryon number this ansatz produces the lowest energy solutions known so far . by considering the geometry of the model we find an approximate analytic formula for the shape function this provides an insight why... | this paper discusses multi - skyrmions on the-sphere with variable radius using the rational map ansatz . for baryon number this ansatz produces the lowest energy solutions known so far . by considering the geometry of the model we find an approximate analytic formula for the shape function this provides an insight why... |
astro-ph9905235 | i | planets and brown dwarfs have now been detected around several main sequence stars ( e.g. mayor & queloz 1995 , butler & marcy 1996 , cochran et al . 1997 , rebolo et al . 1995 , 1996 , basri et al . 1996 , marcy et al . 1998 , butler et al . 1998 , delfosse et al . 1998 ) , and strikingly , a fraction of these `` hot ... | we analyze the effects of different accretion rates and different initial conditions . -1 cm -0.65 cm -0.65 cm 2h # 1 accretion - planetary systems - stars : low - mass , brown dwarfs - stars : late type - stars : evolution - stars : mass loss - stars : chemically peculiar - stars : rotation - x - ray : stars - infr... | this paper extends our previous study of planet / brown dwarf accretion by giant stars to solar mass stars located on the red giant branch . the model assumes that the planet is dissipated at the bottom of the convective envelope of the giant star . the giant s evolution is then followed in detail . we analyze the effe... |
astro-ph9905235 | c | in this paper , we investigated the effects of the accretion of a planet or a brown dwarf by a solar type star located on the red giant branch . our computations show that the deposition of mass ( potential energy ) produces a substantial expansion of the envelope and , for higher accretion rates , nuclear burning at t... | this paper extends our previous study of planet / brown dwarf accretion by giant stars to solar mass stars located on the red giant branch . the model assumes that the planet is dissipated at the bottom of the convective envelope of the giant star . the giant s evolution is then followed in detail . the computations in... | this paper extends our previous study of planet / brown dwarf accretion by giant stars to solar mass stars located on the red giant branch . the model assumes that the planet is dissipated at the bottom of the convective envelope of the giant star . the giant s evolution is then followed in detail . we analyze the effe... |
cs0602072 | i | low - density parity - check ( ldpc ) codes as opposed to turbo codes have been studied extensively on the binary erasure channel ( bec ) . in @xcite , an iterative decoding algorithm for ldpc codes over the bec was proposed , and it was shown that this scheme approaches channel capacity arbitrarily close . although ca... | we then adapt the concept of stopping sets to turbo decoding and state an exact condition for decoding failure . then the set of erased positions that will remain when the decoder stops is equal to the unique maximum - size _ turbo stopping set _ which is also a subset of the set of erased positions . finally , we give... | this paper is devoted to the finite - length analysis of turbo decoding over the binary erasure channel ( bec ) . the performance of iterative belief - propagation ( bp ) decoding of low - density parity - check ( ldpc ) codes over the bec can be characterized in terms of _ stopping sets_. we describe turbo decoding on... |
cs0602072 | c | in this work we have considered the finite - length analysis of turbo decoding on the bec . in the same way as iterative bp decoding of ldpc codes is simpler on the bec than on other channels , turbo decoding can also be simplified on this channel . based on this simplified turbo decoding algorithm we have introduced t... | this paper is devoted to the finite - length analysis of turbo decoding over the binary erasure channel ( bec ) . the performance of iterative belief - propagation ( bp ) decoding of low - density parity - check ( ldpc ) codes over the bec can be characterized in terms of _ stopping sets_. we describe turbo decoding on... | this paper is devoted to the finite - length analysis of turbo decoding over the binary erasure channel ( bec ) . the performance of iterative belief - propagation ( bp ) decoding of low - density parity - check ( ldpc ) codes over the bec can be characterized in terms of _ stopping sets_. we describe turbo decoding on... |
astro-ph0303550 | c | the observed difference of the @xmath1 contribution to the total light between binaries from a and b subsets may be understood as follows . the components of binaries from b subset are relatively much closer to each other than those from a subset and the proximity effects , depending on the gravitational distortion and... | this paper presents a careful and detailed light curve analysis of bright detached eclipsing binaries ( deb ) in the small magellanic cloud , discovered by ogle collaboration , on the basis of recently available difference image analysis ( dia ) photometry . the physical properties of the stars were estimated on the ba... | this paper presents a careful and detailed light curve analysis of bright detached eclipsing binaries ( deb ) in the small magellanic cloud , discovered by ogle collaboration , on the basis of recently available difference image analysis ( dia ) photometry . the 19 binaries brighter than 16.4 mag in band and with the d... |
1501.02524 | i | it has been speculated that quantum computers , which harness physical phenomenon unique to quantum mechanics ( especially quantum interference and superposition ) to realize a fundamentally new mode of information processing , can overcome the limitation of classical computers in efficiently solving hard computational... | this paper presents a physical mapping tool for quantum circuits , which generates the optimal universal logic block ( ulb ) that can , on average , perform any logical fault - tolerant ( ft ) quantum operations with the minimum latency . in addition to the quantum physical mapper , an approach is presented to determin... | this paper presents a physical mapping tool for quantum circuits , which generates the optimal universal logic block ( ulb ) that can , on average , perform any logical fault - tolerant ( ft ) quantum operations with the minimum latency . the operation scheduling , placement , and qubit routing problems tackled by the ... |
1501.02524 | r | qufd is implemented in java . trapped - ion parameters used for the simulations are as follows : move delay=10@xmath84 ; one - qubit primitive instruction delay=50@xmath85s@xmath86 and two - qubit primitive instruction delay=100@xmath84 . a workstation with intel core i7 - 2600 3.4ghz cpu and 8 gb ram was used to run t... | more precisely , the scheduling solution affects the quality of the achievable placement solution due to resource pressures that may be created as a result of operation scheduling whereas the operation placement and qubit routing solutions influence the scheduling solution due to resulting distances between predecessor... | this paper presents a physical mapping tool for quantum circuits , which generates the optimal universal logic block ( ulb ) that can , on average , perform any logical fault - tolerant ( ft ) quantum operations with the minimum latency . the operation scheduling , placement , and qubit routing problems tackled by the ... |
1501.02524 | c | this paper presented quantum scheduling and placement algorithms for mapping fault - tolerant quantum operations to a universal logic block ( ulb ) . analytical formulations for the scheduling and placement problems were also presented . effective and state - of - the - art algorithms used in standard cad tools for cla... | the proposed flow for the quantum physical mapper captures these dependencies by applying ( i ) a loose scheduling step , which transforms an initial quantum data flow graph into one that explicitly captures the no - cloning theorem of the quantum computing and then performs instruction scheduling based on a modified f... | this paper presents a physical mapping tool for quantum circuits , which generates the optimal universal logic block ( ulb ) that can , on average , perform any logical fault - tolerant ( ft ) quantum operations with the minimum latency . the operation scheduling , placement , and qubit routing problems tackled by the ... |
0705.1853 | i | rank rigidity was first proved in the higher euclidean rank setting by ballman @xcite and , using different methods , by burns and spatzier @xcite . a manifold is said to have higher euclidean rank if a parallel , normal jacobi field can be found along every geodesic . ballman and burns - spatzier proved that if an irr... | this paper presents hyperbolic rank rigidity results for rank 1 , nonpositively curved spaces . let be a compact , rank 1 manifold with nonpositive sectional curvature and suppose that along every geodesic in there is a parallel vector field making curvature with the geodesic direction . when is the upper curvature bou... | this paper presents hyperbolic rank rigidity results for rank 1 , nonpositively curved spaces . let be a compact , rank 1 manifold with nonpositive sectional curvature and suppose that along every geodesic in there is a parallel vector field making curvature with the geodesic direction . we prove that has constant curv... |
cond-mat0504380 | i | a better understanding of the electron - correlation driven volume collapse transitions in the compressed lanthanides may come from putting this behavior in context of their extended evolution from localized to itinerant character . to this end , the present paper has reported calculations for compressed ce ( @xmath0 )... | this paper reports calculations for compressed ce ( ) , pr ( ) , and nd ( ) using a combination of the local - density approximation ( lda ) and dynamical mean field theory ( dmft ) , or lda+dmft . the moment , spectra , and the total energy among other properties are examined as functions of volume and atomic number f... | this paper reports calculations for compressed ce ( ) , pr ( ) , and nd ( ) using a combination of the local - density approximation ( lda ) and dynamical mean field theory ( dmft ) , or lda+dmft . the moment , spectra , and the total energy among other properties are examined as functions of volume and atomic number f... |
gr-qc0312030 | c | to date , the only fully general relativistic simulations of corotating binary , @xmath123 polytropes is @xcite . the study in @xcite differs from the present study in several important ways . one basic difference is that while we focus on the capability of simulating astrophysical realistic neutron star binaries , @... | we show that the cfqe assumptions significantly violate the einstein field equations for corotating neutron stars at orbital separations nearly double that of the innermost stable circular orbit ( isco ) separation , thus calling into question the astrophysical relevance of the isco determined in the cfqe approach . ... | this paper reports on our effort in modeling realistic astrophysical neutron star binaries in general relativity . we analyze under what conditions the conformally flat quasiequilibrium ( cfqe ) approach can generate `` astrophysically relevant '' initial data , by developing an analysis that determines the violation o... |
1010.1294 | i | we address here the following question : what is the asymptotic size and the limit laws of the smallest and largest gaps or spacings in the spectra of random matrices ? typical spacings between eigenvalues of random matrices have been well understood for invariant ensembles for quite some time . more recently , the beh... | this paper studies the extreme gaps between eigenvalues of random matrices . we give the joint limiting law of the smallest gaps for haar - distributed unitary matrices and matrices from the gaussian unitary ensemble . in particular , theth smallest gap , normalized by a factor , has a limiting density proportional to ... | this paper studies the extreme gaps between eigenvalues of random matrices . we give the joint limiting law of the smallest gaps for haar - distributed unitary matrices and matrices from the gaussian unitary ensemble . in particular , theth smallest gap , normalized by a factor , has a limiting density proportional to ... |
1311.0629 | i | s. t. belyaev s contribution to theoretical physics is very impressive . in 1958 s. t. belyaev has published his classical works on the theory of nonideal bose - gas . in these works , s. t. belyaev demonstrates that peculiarity of bose systems comes from a microscopic number of particles in the condensed state with th... | belyaev s ideas associated with the condensate state in bose interacting systems have stimulated intensive studies of the possible manifestation of such a condensation in fermi systems . in many fermi systems and compounds at zero temperature a phase transition happens that leads to a quite specific state called fermio... | this short review paper devoted to 90th anniversary of s. t. belyaev birthday . belyaev s ideas associated with the condensate state in bose interacting systems have stimulated intensive studies of the possible manifestation of such a condensation in fermi systems . in many fermi systems and compounds at zero temperatu... |
1311.0629 | i | the condensate state in bose interacting systems , introduced by s. t. belyaev in his famous papers , forms the system s properties . it turns out that the fermion condensate takes place in many compounds , and generates the non - fermi liquid behavior by forming flat bands . we have for the first time theoretically ca... | our discussion shows that the theory of fermion condensation develops completely good description of the nfl behavior of strongly correlated fermi systems . moreover , the fermion condensation can be considered as the universal reason for the nfl behavior observed in various hf metals , liquids , compounds with quantum... | this short review paper devoted to 90th anniversary of s. t. belyaev birthday . belyaev s ideas associated with the condensate state in bose interacting systems have stimulated intensive studies of the possible manifestation of such a condensation in fermi systems . in many fermi systems and compounds at zero temperatu... |
1306.0721 | i | ultrafast spectroscopy with a time resolution as high as @xmath0s is essential for understanding many quantum dynamical processes in chemical physics.@xcite although short time scales should simplify theoretical studies by requiring shorter simulations , solving the time - dependent schrdinger equation ( tdse ) is chal... | we improve both the accuracy of this approximation with an amplitude correction derived from the phase - space propagator and its efficiency with an improved cellular scheme employing inverse weierstrass transform and optimal scaling of the cell size . we demonstrate the advantages of the new methodology by computin... | time - resolved electronic spectra can be obtained as the fourier transform of a special type of time correlation function known as fidelity amplitude , which , in turn , can be evaluated approximately and efficiently with the dephasing representation . here we improve both the accuracy of this approximation with an a... |
astro-ph0612671 | m | first we will look in a bit more detail into our equations of state before elaborating on the construction of the planet models . the total pressure , ( @xmath7 ) , can be expressed as : @xmath8 where @xmath9 is the pressure at zero - temperature and @xmath10 is the thermal pressure . for the degenerate interiors of ma... | masses ranging from 0.01 earth masses to 10 jupiter masses at orbital distances of 0.02 to 10 au are considered . for hydrogen - helium rich planets , our models are the first to couple planetary evolution to stellar irradiation over a wide range of orbital separations ( 0.02 to 10 au ) through a non - gray radiative -... | to aid in the physical interpretation of planetary radii constrained through observations of transiting planets , or eventually direct detections , we compute model radii of pure hydrogen - helium , water , rock , and iron planets , along with various mixtures . masses ranging from 0.01 earth masses to 10 jupiter masse... |
1204.5111 | i | the rapidly improving experimental techniques to probe magnetic adatoms on non - magnetic surfaces allow for direct studies of fundamental magnetic exchange mechanisms on an atomic scale . besides access to the structural and the electronic properties of such adatoms and of the underlying substrate for a given system ,... | to analyze the physical properties arising from indirect magnetic exchange between several magnetic adatoms and between complex magnetic nanostructures on metallic surfaces , the real - space extension of dynamical mean - field theory ( r - dmft ) appears attractive as it can be applied to systems of almost arbitrary g... | to analyze the physical properties arising from indirect magnetic exchange between several magnetic adatoms and between complex magnetic nanostructures on metallic surfaces , the real - space extension of dynamical mean - field theory ( r - dmft ) appears attractive as it can be applied to systems of almost arbitrary g... |
1204.5111 | c | conventional ( rkky ) theory of indirect magnetic exchange predicts an effective exchange interaction @xmath258 where @xmath259 is the nonlocal static susceptibility of the metallic host . this interaction survives , as a nearest - neighbor coupling , @xcite even in the case of two magnetic impurities embedded in an in... | while r - dmft describes the kondo effect of a single adatom exactly , indirect magnetic ( rkky ) exchange is taken into account on an approximate level only . here this two - impurity anderson model incorporates the competition between the kondo effect and indirect exchange but is amenable to an exact numerical soluti... | to analyze the physical properties arising from indirect magnetic exchange between several magnetic adatoms and between complex magnetic nanostructures on metallic surfaces , the real - space extension of dynamical mean - field theory ( r - dmft ) appears attractive as it can be applied to systems of almost arbitrary g... |
astro-ph0606530 | i | we presented a study of the spatially - resolved dynamics in the optical emission line gas around the z@xmath02.16 powerful radio galaxy mrc1138 - 262 , using the near - infrared integral - field spectrograph spiffi on ut1 of the vlt . the large - scale kinematics in the emission line nebula of this galaxy are not cons... | to explain the properties of the most massive low - redshift galaxies and the shape of their mass function , recent models of galaxy evolution include strong agn feedback to complement starburst - driven feedback in massive galaxies . using the near - infrared integral - field spectrograph spiffi on the vlt , we search... | to explain the properties of the most massive low - redshift galaxies and the shape of their mass function , recent models of galaxy evolution include strong agn feedback to complement starburst - driven feedback in massive galaxies . using the near - infrared integral - field spectrograph spiffi on the vlt , we search... |
0912.2159 | r | , 76 sources , left panel ) and the @xmath87\lambda 5007 $ ] line luminosity ( @xmath88 $ ] , 46 sources , right panel ) for h@xmath2o maser sources ( solid lines ) , in units of ergs@xmath86 . for comparison , the distributions are also given for a seyfert 2 sample without known h@xmath2o maser emission ( dashed lines... | can be established for compton - thick nuclear regions . there are no obvious correlations between the ew ( k ) , the $ ] luminosity and the isotropic ho maser luminosity . when comparing samples of seyfert 2s with and without detected ho maser lines , there seem to exist differences in ew ( k ) and the fraction of co... | to shed light onto the circumnuclear environment of 22 ghz ( 1.3 cm ) ho maser galaxies , we have analyzed some of their multi - wavelength properties , including the far infrared luminosity ( fir ) , the luminosity of the\lambda5007 $ ] emission line , the nuclear x - ray luminosity , and the equivalent width of the n... |
0912.2159 | i | in this paper , multi - wavelength data from the complete sample of galaxies ( @xmath111@xmath7100kpc ) so far reported to host 22ghz h@xmath2o masers are analyzed , including the equivalent width ( ew ) of the iron @xmath6 line , the @xmath3\lambda 5007 $ ] line , and the x - ray and fir emission . the latter two are ... | there are strong anti - correlations between ew ( ) and two `` optical thickness parameters '' , i.e. the ratios of the x - ray luminosity versus the presumably more isotropically radiated $ ] and far infrared ( fir ) luminosities . based on these anti - correlations , a set of quantitative criteria , ew ()ev ,}$ ] and | to shed light onto the circumnuclear environment of 22 ghz ( 1.3 cm ) ho maser galaxies , we have analyzed some of their multi - wavelength properties , including the far infrared luminosity ( fir ) , the luminosity of the\lambda5007 $ ] emission line , the nuclear x - ray luminosity , and the equivalent width of the n... |
hep-th9907119 | i | many a time advances in mathematics and physics have occurred hand in hand . newton s theory of mechanics and the development of techniques of calculus are a classical example of this phenomenon . another example is the developments in differential geometry inspired by maxwell theory of electromagnetism and einstein th... | chern - simons theories , which are examples of such field theories , provide a field theoretic framework for the study of knots and links in three dimensions . not only in mathematics , chern - simons theories find important applications in three and four dimensional quantum gravity also . | topological quantum field theories can be used as a powerful tool to probe geometry and topology in low dimensions . chern - simons theories , which are examples of such field theories , provide a field theoretic framework for the study of knots and links in three dimensions . these are rare examples of quantum field t... |
1305.0133 | i | excitons are electrically neutral and have finite lifetimes . these are two obstacles which make the development of excitonic spintronics , or spin - optronics challenging . how possibly one can explore the current , which is carried by neutral particles , and whose amplitude changes with distance and time ? - is a fai... | traditional spintronics relies on spin transport by charge carriers , such as electrons in semiconductor crystals . the challenges for the realization of long - range electron spin transport include rapid spin relaxation due to electron scattering . they can form coherent quantum liquids that carry spins over macroscop... | traditional spintronics relies on spin transport by charge carriers , such as electrons in semiconductor crystals . the challenges for the realization of long - range electron spin transport include rapid spin relaxation due to electron scattering . scattering and , in turn , spin relaxation can be effectively suppress... |
1305.0133 | c | bosonic spin transport is a young and promising area of solid - state physics . the theories of mesoscopic transport of charge carriers and quantum transport are among the most interesting chapters of modern physics . substitution of fermions by bosons and of a scalar electric charge by a spin vector can not be formall... | scattering and , in turn , spin relaxation can be effectively suppressed in excitonic devices where the spin currents are carried by electrically neutral bosonic quasi - particles : excitons or exciton - polaritons . we also consider exciton transport in the non - linear regime and discuss the definitions of the excito... | traditional spintronics relies on spin transport by charge carriers , such as electrons in semiconductor crystals . the challenges for the realization of long - range electron spin transport include rapid spin relaxation due to electron scattering . scattering and , in turn , spin relaxation can be effectively suppress... |
0910.0332 | i | there is strong observational and theoretical evidence that magnetic fields play a crucial role in the acceleration and the collimation of extragalactic jets . most active galactic nuclei ( agn ) jet formation scenarios involve magnetic fields threading a rotating black hole ( in the ergosphere ) and its accretion disk... | transverse stratification is a common intrinsic feature of astrophysical jets . there is growing evidence that jets in radio galaxies consist of a fast low density outflow at the jet axis , surrounded by a slower , denser , extended jet . we here investigate the stability of rotating , two - component relativistic outf... | transverse stratification is a common intrinsic feature of astrophysical jets . there is growing evidence that jets in radio galaxies consist of a fast low density outflow at the jet axis , surrounded by a slower , denser , extended jet . the inner and outer jet components then have a different origin and launching mec... |
0910.0332 | c | we examined five configurations of magnetized two - component jets . all share the same density ratio between inner and outer component and identical rotation profiles . the magnetic and thermal pressure configuration in each model differs , though . this in turn translates to different distributions of the ( total , f... | their interface will develop differential rotation , where disruptions may occur . we include cases with poloidally magnetized jet components , covering hydro and magnetohydrodynamic models . with grid - adaptive relativistic magnetohydrodynamic simulations , augmented with approximate linear stability analysis we demo... | transverse stratification is a common intrinsic feature of astrophysical jets . there is growing evidence that jets in radio galaxies consist of a fast low density outflow at the jet axis , surrounded by a slower , denser , extended jet . the inner and outer jet components then have a different origin and launching mec... |
1606.07987 | i | computational fluid dynamics ( cfd ) simulations have been widely used in aerospace , mechanical , and chemical industries to support engineering design , analysis , and optimization . two decades ago when large eddy simulations ( les ) started gaining popularity with the increasing availability of computational resour... | turbulence modeling is a critical component in numerical simulations of industrial flows based on reynolds - averaged navier - stokes ( rans ) equations . however , after decades of efforts in the turbulence modeling community , universally applicable rans models with predictive capabilities are still lacking . large d... | turbulence modeling is a critical component in numerical simulations of industrial flows based on reynolds - averaged navier - stokes ( rans ) equations . however , after decades of efforts in the turbulence modeling community , universally applicable rans models with predictive capabilities are still lacking . large d... |
1606.07987 | c | in this work , we proposed a physics - informed machine learning approach to reconstruct reynolds stresses modeling discrepancies by utilizing dns databases of training flows sharing similar characteristics as the flow to be predicted . for this purpose , we formulated discrepancy of reynolds stresses ( or more precise... | we propose a data - driven , physics - informed machine learning approach for reconstructing discrepancies in rans modeled reynolds stresses . the discrepancies are formulated as functions of the mean flow features . by using a modern machine learning technique based on random forests , the discrepancy functions are tr... | turbulence modeling is a critical component in numerical simulations of industrial flows based on reynolds - averaged navier - stokes ( rans ) equations . however , after decades of efforts in the turbulence modeling community , universally applicable rans models with predictive capabilities are still lacking . large d... |
astro-ph0002385 | i | perhaps the most perplexing and long - standing problem associated with galactic and cluster cooling flows is the uncertain physical nature and spatial distribution of the gas that cools . the apparent absence of large masses of cooled gas in elliptical galaxies has led some to argue that little or no cooling actually ... | typically percent of the total baryonic mass in luminous elliptical galaxies is in the form of cooled interstellar gas . although the mass contributed by cooled gas is small relative to the mass of the old stellar system in these galaxies , it is almost certainly concentrated within the optical effective radius where i... | typically percent of the total baryonic mass in luminous elliptical galaxies is in the form of cooled interstellar gas . although the mass contributed by cooled gas is small relative to the mass of the old stellar system in these galaxies , it is almost certainly concentrated within the optical effective radius where i... |
1408.0352 | i | coronal mass ejections ( cmes ) are huge magnetized plasma expulsions from the sun into the heliosphere and are considered as primary drivers of geomagnetic storms and various other space weather effects @xcite . it is therefore required to improve the physics and our understanding of evolution of cmes in the solar win... | it is found that kinematics of cmes can change when they interact or collide with each other as they propagate in the heliosphere . in this paper our analysis shows an improvement in arrival time prediction of cmes using their post - collision dynamics than using pre - collision dynamics . estimating the true masses an... | understanding of the kinematic evolution of coronal mass ejections ( cmes ) in the heliosphere is important to estimate their arrival time at the earth . it is found that kinematics of cmes can change when they interact or collide with each other as they propagate in the heliosphere . in this paper , we analyze the col... |
1408.0352 | r | in this paper , we have studied the interactions between two successively launched earth directed cmes from the sun on 2012 november 9 and 10 , respectively . the analysis involved remote sensing observations of cme propagation in inner heliosphere from secchi / cor2 and hi images and the associated in situ measurement... | , we analyze the collision and post - interaction characteristics of two earth - directed cmes , launched successively on 2012 november 9 and 10 , using white light imaging observations from stereo / secchi and in situ observations taken from wind spacecraft . we also estimated the kinematics of these features of the c... | understanding of the kinematic evolution of coronal mass ejections ( cmes ) in the heliosphere is important to estimate their arrival time at the earth . it is found that kinematics of cmes can change when they interact or collide with each other as they propagate in the heliosphere . in this paper , we analyze the col... |
1401.6866 | i | since several decades polymer brushes find abiding interest for various applications , and have been studied very intensively by experiment , analytical theory , and computer simulations @xcite . the structure of these soft polymeric layers and their response to various external perturbations depends in a delicate way ... | using a coarse - grained bead - spring model for semi - flexible macromolecules forming a polymer brush , structure and dynamics of the polymers is investigated , varying chain stiffness and grafting density . the anchoring condition for the grafted chains is chosen such that their first bonds are oriented along the no... | using a coarse - grained bead - spring model for semi - flexible macromolecules forming a polymer brush , structure and dynamics of the polymers is investigated , varying chain stiffness and grafting density . the anchoring condition for the grafted chains is chosen such that their first bonds are oriented along the no... |
astro-ph0203319 | c | the advent of x - ray telescopes with large effective areas and instruments for high resolution spectroscopy opens a new window on the intergalactic medium , one that could reveal a large reservoir of previously hidden baryons . we have used a hydrodynamic simulation of the @xmath0cdm cosmological model to predict the ... | using a hydrodynamic simulation of a cold dark matter universe with a cosmological constant (cdm ) , we investigate the `` x - ray forest '' absorption imprinted on the spectra of background quasars by the intervening intergalactic medium ( igm ) , at redshift . in agreement with previous studies , we find that and p... | using a hydrodynamic simulation of a cold dark matter universe with a cosmological constant (cdm ) , we investigate the `` x - ray forest '' absorption imprinted on the spectra of background quasars by the intervening intergalactic medium ( igm ) , at redshift . in agreement with previous studies , we find that and p... |
astro-ph0206344 | c | we have used gemini - north to study the stellar populations in the central regions of m33 . the surface brightness profiles from @xmath4 to @xmath5 , formed from the combination of our data and those of @xcite , show that the data need to be modeled using a three - component , core + spheroid + disk model . the best -... | based on the slope of the giant branch we estimate the mean metallicity to be , and from the luminosities of the most luminous stars , we estimate that there were two bursts of star formation and gyr ago . we combine our infrared gemini data with optical hst - wfpc2 measurements revealing a cmd populated with young , i... | using gemini quickstart infrared observations of the central of m33 , we analyze the stellar populations in this controversial region . based on the slope of the giant branch we estimate the mean metallicity to be , and from the luminosities of the most luminous stars , we estimate that there were two bursts of star fo... |
1608.01473 | c | * detailed look into water flux across the tm domain . * in order to glean the molecular origin of receptor state - dependent water flux , we first visualize the geometry of water channel . the radius of water channel , calculated using the program hole @xcite ( see figure [ water_flux_analysis]a ) , reveals that the g... | water molecules inside g - protein coupled receptor have recently been spotlighted in a series of crystal structures . to decipher the dynamics and functional roles of internal waters in gpcr activity our study finds that the amount of water flux across the transmembrane ( tm ) domain varies depending on the receptor s... | water molecules inside g - protein coupled receptor have recently been spotlighted in a series of crystal structures . to decipher the dynamics and functional roles of internal waters in gpcr activity , we studied a adenosine receptor usingsec - molecular dynamics simulations . our study finds that the amount of water ... |
1103.0672 | i | this article is a continuation of @xcite , in which we introduced the notion of symplectic microfolds and symplectic micromorphisms between them . recall that a symplectic microfold is essentially the same thing as a germ @xmath0 $ ] of symplectic manifolds @xmath1 around a lagrangian submanifold @xmath2 , called the c... | we adapt the notion of generating functions for lagrangian submanifolds to symplectic microgeometry . we show that a symplectic micromorphism always admits a global generating function . as an application , we describe hamiltonian flows as special symplectic micromorphisms whose local generating functions are the solut... | we adapt the notion of generating functions for lagrangian submanifolds to symplectic microgeometry . we show that a symplectic micromorphism always admits a global generating function . as an application , we describe hamiltonian flows as special symplectic micromorphisms whose local generating functions are the solut... |
1101.4102 | i | congestion phenomena in population dynamics cover a wide range of mechanisms , which can be classified according to their stiffness : 1 . soft congestion : as the distance between individuals becomes smaller , the behavior of a single person is affected by the presence of others ; 2 . hard congestion : actual con... | we develop those principles in the microscopic and macroscopic settings , and we present how the framework of wasserstein distance between measures allows to recover the _ sweeping process _ micro and macro approaches are compared , and we investigate the similarities together with deep differences of those two levels ... | we address here the issue of congestion in the modeling of crowd motion , in the non - smooth framework : contacts between people are not anticipated and avoided , they actually occur , and they are explicitly taken into account in the model . we limit our approach to very basic principles in terms of behavior , to foc... |
0806.2608 | i | the stability of the electroweak scale has driven the high energy physics community , both theorists and experimentalists alike , for nearly the past two decades . with the advent of the large hadron collider ( lhc ) , we can finally probe the mechanism of electroweak symmetry breaking ( ewsb ) and possibly new physics... | we address the possible scenario that the large hadron collider ( lhc ) discovers only a higgs boson after 10 fb of operation , and attempt to identify this higgs boson as that of the standard model ( sm ) , the minimal universal extra dimension model ( mued ) , the littlest higgs model with-parity ( lht ) , or the min... | we address the possible scenario that the large hadron collider ( lhc ) discovers only a higgs boson after 10 fb of operation , and attempt to identify this higgs boson as that of the standard model ( sm ) , the minimal universal extra dimension model ( mued ) , the littlest higgs model with-parity ( lht ) , or the min... |
1103.0088 | i | it is a classical fact in complex geometry that the singular kummer surface @xmath5 attached to an abelian surface @xmath6 has sixteen rational double points , and an irreducible principal polarization embeds it as a quartic surface in @xmath4 , compare hudson s classical monography @xcite , or for a modern account @xc... | we analyse the diagonal quotient for the product of certain artin schreier curves . the calculation of numerical invariants relies on a close examination of the relevant wild quotient singularity in characteristic . it turns out that the canonical model has rational double points of type , and embeds as a divisor of d... | we analyse the diagonal quotient for the product of certain artin schreier curves . the smooth models are almost always surfaces of general type , with chern slopes tending asymptotically to 1 . the calculation of numerical invariants relies on a close examination of the relevant wild quotient singularity in character... |
cond-mat0108023 | i | quantifying correlations between different stocks is a topic of interest not only for scientific reasons of understanding the economy as a complex dynamical system , but also for practical reasons such as asset allocation and portfolio - risk estimation @xcite . unlike most physical systems , where one relates correla... | we test the statistics of the eigenvalues of * c * against a `` null hypothesis '' a random correlation matrix constructed from mutually uncorrelated time series . we test the eigenvalues of * c * within the rmt bound for universal properties of random matrices and find good agreement with the results for the gaussian... | we analyze cross - correlations between price fluctuations of different stocks using methods of random matrix theory ( rmt ) . using two large databases , we calculate cross - correlation matrices * c * of returns constructed from ( i ) 30-min returns of 1000 us stocks for the 2-yr period 199495 ( ii ) 30-min returns o... |
cond-mat0108023 | c | how can we understand the deviating eigenvalues i.e. , correlations that are stable in time ? one approach is to postulate that returns can be separated into idiosyncratic and common components i.e. , that returns can be separated into different additive `` factors '' , which represent various economic influences tha... | in addition , we find that these `` deviating eigenvectors '' are stable in time . we analyze the components of the deviating eigenvectors and find that the largest eigenvalue corresponds to an influence common to all stocks . our analysis of the remaining deviating eigenvectors shows distinct groups , whose identities... | we analyze cross - correlations between price fluctuations of different stocks using methods of random matrix theory ( rmt ) . using two large databases , we calculate cross - correlation matrices * c * of returns constructed from ( i ) 30-min returns of 1000 us stocks for the 2-yr period 199495 ( ii ) 30-min returns o... |
1208.0983 | c | we have observed line - of - sight emission spectra in 31 nearby , low metallicity dirr galaxies in order to search for cold defined by a velocity dispersion of less than 6 km s@xmath1 . we have detected it in 23 of 27 galaxies after quality control cuts were applied . the cold may be the future sites of molecular c... | cold is found in 23 of 27 (% ) galaxies after a reduction of the sample size due to quality control cuts . the cold contributes% of the total line - of - sight flux when found with warm . we find a lower limit for the mass fraction of cold - to - total gas of only a few percent in each galaxy . | we analyze line - of - sight atomic hydrogen ( ) line profiles of 31 nearby , low - mass galaxies selected from the very large array - acs nearby galaxy survey treasury ( vla - angst ) and the nearby galaxy survey ( things ) to trace regions containing cold ( t 1400 k ) from observations with a uniform linear scale o... |
hep-th9908194 | i | cosmic strings are a special case of the vorticity phenomenon , which appears in many forms - in the flow of rivers and streams , in smoke rings , in hurricanes and tornadoes , etc . a special case of vorticity are the _ quantum vortices _ @xcite which include vortices in superfluids , flux tubes in superconductors and... | we apply the concept of helicity from classical hydrodynamics to elucidate two problematical issues in cosmic string physics . helicity , the space integral of the scalar product of a velocity - like field with its vorticity field ( curl ) , can be defined for a complex scalar field in analogy with fluids . we dwell on... | we apply the concept of helicity from classical hydrodynamics to elucidate two problematical issues in cosmic string physics . helicity , the space integral of the scalar product of a velocity - like field with its vorticity field ( curl ) , can be defined for a complex scalar field in analogy with fluids . we dwell on... |
1406.7707 | c | .[tab : gate_error]summary of the quantum gate errors [ cols="^,^,^,^,^",options="header " , ] we have applied the quantum optimal control method to implement fast and high - fidelity single - qubit and two - qubit gates for two inductively coupled superconducting flux qubits with fixed static off - diagonal qubit ... | we apply the quantum optimal control theory based on the krotov method to implement single - qubit and gates and two - qubit cnot gates for inductively coupled superconducting flux qubits with fixed qubit transition frequencies and fixed off - diagonal qubit - qubit coupling . our scheme that shares the same advantage ... | we apply the quantum optimal control theory based on the krotov method to implement single - qubit and gates and two - qubit cnot gates for inductively coupled superconducting flux qubits with fixed qubit transition frequencies and fixed off - diagonal qubit - qubit coupling . our scheme that shares the same advantage ... |
1309.4805 | i | in this paper , the validity of various exchange - correlation functionals ( lda , pbe , pbesol , wc , am05 , and htbs ) has been investigated for computing the structural , vibrational , dielectric , and thermodynamical properties of various materials ( silicon , sio@xmath0 @xmath1-quartz and stishovite , zrsio@xmath2... | we assess the validity of various exchange - correlation functionals for computing the structural , vibrational , dielectric , and thermodynamical properties of materials in the framework of density - functional perturbation theory ( dfpt ) . we investigate a wide variety of materials including a semiconductor ( silico... | we assess the validity of various exchange - correlation functionals for computing the structural , vibrational , dielectric , and thermodynamical properties of materials in the framework of density - functional perturbation theory ( dfpt ) . we consider five generalized - gradient approximation ( gga ) functionals ( p... |
1601.06845 | i | 0.1 cm the parity - violating ( chiral ) gauge symmetries and spontaneous / explicit breaking of these symmetries for the hierarchy of fermion masses have been at the center of a conceptual elaboration that has played a major role in donating to mankind the beauty of the sm for particle physics . the nambu - jona - las... | we briefly recall the previous publications plb1996,2013,2014,2015,npb1997,2000 and prd2000,2001,2016 on the effective field theory of massive ( tev ) composite particles and their sm gauge couplings in the domain of uv - stable fixed point of relevant four - fermion operators , and on the resonant and nonresonant phen... | we briefly recall the previous publications plb1996,2013,2014,2015,npb1997,2000 and prd2000,2001,2016 on the effective field theory of massive ( tev ) composite particles and their sm gauge couplings in the domain of uv - stable fixed point of relevant four - fermion operators , and on the resonant and nonresonant phen... |
1601.06845 | r | 0.1 cm for readers convenience , we first give a very brief review of effective four - fermion operators and the effective theory of composite particles , which were presented in previous papers . we then focus the discussions on the decay and annihilation channels of composite bosons and fermions into the final states... | we then focus the discussions on the decay and annihilation channels of composite particles into the final states of the sm gauge bosons , leptons and quarks in connection with the on - going searches of the atlas and cms experiments at energy tev . these provide the justification for the verification or falsification ... | we briefly recall the previous publications plb1996,2013,2014,2015,npb1997,2000 and prd2000,2001,2016 on the effective field theory of massive ( tev ) composite particles and their sm gauge couplings in the domain of uv - stable fixed point of relevant four - fermion operators , and on the resonant and nonresonant phen... |
hep-th9802076 | i | the chern - simons formulation of 2 + 1 dimensional gravity @xcite has provided many interesting new insights into the problem of quantum gravity . ( for a review see @xcite . ) most notably , making use of the relationship between 2 + 1 dimensional chern - simons theory and the 1 + 1 dimensional wzw model @xcite , car... | we define the partition function by using a surface term at infinity that is compatible with fixing the temperature and angular velocity of the black hole . we then compute the partition function directly in a boundary wess - zumino - witten theory , and find that we obtain the correct result only after we include a so... | we calculate the density of states of the 2 + 1 dimensional btz black hole in the micro- and grand - canonical ensembles . our starting point is the relation between 2 + 1 dimensional quantum gravity and quantised chern - simons theory . in the micro - canonical ensemble , we find the bekenstein hawking entropy by rel... |
hep-th9802076 | c | we have performed two separate calculations of the entropy of the 2 + 1 dimensional black hole using the relation between 2 + 1 dimensional gravity and chern - simons theory . in sec . 2 , we have worked in the micro - canonical ensemble , and have calculated the density of states starting from the kac - moody algebra ... | we calculate the density of states of the 2 + 1 dimensional btz black hole in the micro- and grand - canonical ensembles . our starting point is the relation between 2 + 1 dimensional quantum gravity and quantised chern - simons theory . in the micro - canonical ensemble , we find the bekenstein hawking entropy by rel... | we calculate the density of states of the 2 + 1 dimensional btz black hole in the micro- and grand - canonical ensembles . our starting point is the relation between 2 + 1 dimensional quantum gravity and quantised chern - simons theory . in the micro - canonical ensemble , we find the bekenstein hawking entropy by rel... |
cond-mat0411069 | i | we calculated the critical current @xmath0 versus ( 001 ) in - plane tilt angle @xmath163 for symmetric and asymmetric grain boundary junctions , assuming the order parameter has either the @xmath1- , extended-@xmath1- , or @xmath2-wave form . we used two fermi surfaces appropriate for hole - doped cuprates , one appro... | we calculate the josephson critical current across in - plane ( 001 ) tilt grain boundary junctions of high temperature superconductors . our results are generally in agreement with the sigrist - rice form for ideal junctions that has been used to interpret `` phase - sensitive '' experiments consisting of such in - pl... | we calculate the josephson critical current across in - plane ( 001 ) tilt grain boundary junctions of high temperature superconductors . we solve for the electronic states corresponding to the electron - doped cuprates , two slightly different hole - doped cuprates , and an extremely underdoped hole - doped cuprate in... |
astro-ph0505089 | i | we have calculated in a consistent way five near - infrared theoretical isochrones for filter sets @xmath68 , @xmath121 , @xmath122 , f160w@xmath14f205w , and f160w@xmath14f222 m . we presented isochrones for @xmath51 of 0.0001 to 0.03 , and age of @xmath74 to @xmath59 yr . even in the same vega magnitude system , nea... | even when displayed in the same vega magnitude system , the near - infrared colors of the same isochrone can differ by up to 0.18 mag at its bright end , depending on the filter . we present magnitude transformations between-band filters as a function of color from & band filters . we find that care is needed when comp... | we calculate theoretical isochrones , in a consistent way , for five filters in the atmospheric window between and , , , , f205w , and f222 m , using the padova stellar evolutionary models by girardi et al . even when displayed in the same vega magnitude system , the near - infrared colors of the same isochrone can dif... |
1109.0235 | i | the evolution of galaxies involves the birth and death of stars , therefore , galaxies unavoidably produce metals as they live . thus , galaxies with very low metallic content are probably unevolved objects , and if we find them nearby , they provide a readily accessible fossil record from the early universe . these ob... | the xmp candidates are found by classifying all the galaxies according to the form of their spectra in a region 80 wide around h . due to the data size , the method requires an automatic classification algorithm . our systematic search renders 32 galaxies having negligible [ nii ] lines , as expected in xmp galaxy sp... | we carry out a systematic search for extremely metal poor ( xmp ) galaxies in the spectroscopic sample of sloan digital sky survey ( sdss ) data release 7 ( dr7 ) . the xmp candidates are found by classifying all the galaxies according to the form of their spectra in a region 80 wide around h . due to the data size , ... |
1109.0235 | c | we have carried out a systematic search for extremely metal poor ( xmp ) galaxies among the spectroscopic sample of sdss / dr7 . these objects are rare , and have a clear cosmological interest as unevolved galaxies probably tracing physical conditions in an early phase of the universe ( see [ intro ] ) . the search i... | we carry out a systematic search for extremely metal poor ( xmp ) galaxies in the spectroscopic sample of sloan digital sky survey ( sdss ) data release 7 ( dr7 ) . we use k - means . this was established after a thorough bibliographic search that yielded only some 130 galaxies known to have an oxygen metallicity ten t... | we carry out a systematic search for extremely metal poor ( xmp ) galaxies in the spectroscopic sample of sloan digital sky survey ( sdss ) data release 7 ( dr7 ) . the xmp candidates are found by classifying all the galaxies according to the form of their spectra in a region 80 wide around h . due to the data size , ... |
astro-ph0212072 | r | note that a full description of the c array results and relevant images have been given in paper i and we have reproduced the zeroth moment c array map in fig . [ carray ] . the remaining the zeroth and first moment maps from the combined data set are shown in fig . [ moments ] , both rotated so that the x axis is para... | the global hi distribution is modeled in detail using a technique which can disentangle the effects of inclination from scale height and can also solve for the average volume density distribution in and perpendicular to the disk . one prominent feature in particular , of mass , m and height , 22 kpc , is seen on the ad... | we combine new vla d array hi data of ngc 2613 with previous high resolution data to show new disk - halo features in this galaxy . the global hi distribution is modeled in detail using a technique which can disentangle the effects of inclination from scale height and can also solve for the average volume density dist... |
astro-ph0212072 | c | there are now several galaxies for which there is evidence for lagging halos . in ngc 891 ( i @xmath46 88.6@xmath38 ) , the rotation curve of the hi halo between _ z _ = 1.4 to 2.8 kpc reveals a peak velocity @xmath4 25 km s@xmath7 lower than in the disk ( swaters et al . 1997 ) . in ngc 5775 ( i = 86@xmath38 ) , the... | numerous discrete disk - halo features are observed , however , achieving heights up to 28 kpc from mid - plane . we have instead investigated the feasibility of such a large feature being produced via buoyancy ( with drag ) within a hot , pre - existing x - ray corona . reasonable plume densities , temperatures , stal... | we combine new vla d array hi data of ngc 2613 with previous high resolution data to show new disk - halo features in this galaxy . the global hi distribution is modeled in detail using a technique which can disentangle the effects of inclination from scale height and can also solve for the average volume density dist... |
astro-ph0212072 | c | new vla d array data of ngc 2613 have been combined with previous higher resolution observations ( chaves & irwin 2001 ) to show a more extensive hi distribution than previously observed . the galaxy is now seen to have a tidal tail on its eastern side due to an interaction with its companion , eso 495-g017 , to the ... | we combine new vla d array hi data of ngc 2613 with previous high resolution data to show new disk - halo features in this galaxy . the model shows that the galaxy s inclination is on the low end of the range given by chaves & irwin ( 2001 ) and that the hi disk is thin ( = 188 pc ) , showing no evidence for halo . ... | we combine new vla d array hi data of ngc 2613 with previous high resolution data to show new disk - halo features in this galaxy . the global hi distribution is modeled in detail using a technique which can disentangle the effects of inclination from scale height and can also solve for the average volume density dist... |
hep-ph0008245 | i | active sterile neutrino oscillations in the early universe can generate large differences in the number densities of relic neutrinos and antineutrinos @xcite . ) and hence unimportant for all parameters of interest . this contrasts starkly with the later studies @xcite . ] the resulting `` lepton asymmetries '' have i... | we comment on the recent paper by a. d. dolgov , s. h. hansen , s. pastor and d. v. semikoz ( dhps ) [ astropart . phys . smirnov the msw effect is the dominant asymmetry amplifier . neither the static nor the dhps approach contains this important physics . however , for this regime the effective potential they empl... | we comment on the recent paper by a. d. dolgov , s. h. hansen , s. pastor and d. v. semikoz ( dhps ) [ astropart . phys . * 14 * , 79 ( 2000 ) ] on the generation of neutrino asymmetries from active sterile neutrino oscillations . we demonstrate that the approximate asymmetry evolution equation obtained therein is a... |
hep-ph0008245 | r | in sec . [ sec4a ] we `` deconstruct '' the dhps equations , while we devote sec . [ fatal ] to pinpointing where in their derivation the msw effect is unknowingly neglected . for comparison with the static approximation , we rewrite dhps s evolution equations in the notation of this comment using the `` conversi... | we demonstrate that the approximate asymmetry evolution equation obtained therein is an expansion , up to a minor discrepancy , of the well - established static approximation equation , valid only when the supposedly new higher order correction term is small . in the regime where this so - called `` back - reaction '' ... | we comment on the recent paper by a. d. dolgov , s. h. hansen , s. pastor and d. v. semikoz ( dhps ) [ astropart . phys . * 14 * , 79 ( 2000 ) ] on the generation of neutrino asymmetries from active sterile neutrino oscillations . we demonstrate that the approximate asymmetry evolution equation obtained therein is a... |
0901.1880 | i | one of the oldest challenges in galaxy formation theory is to explain its overall inefficiency , specifically how to prevent too much gas from cooling onto the central galaxies of dark matter halos and forming stars , resulting in higher - mass galaxies at a given number density than observed ( e.g. * ? ? ? a second , ... | we compare the properties of galaxies that form in a cosmological simulation without strong feedback to observations of the galaxy population . we confirm previous findings that models without strong feedback overproduce the observed galaxy baryonic mass function , especially at the low and high mass extremes . through... | we compare the properties of galaxies that form in a cosmological simulation without strong feedback to observations of the galaxy population . we confirm previous findings that models without strong feedback overproduce the observed galaxy baryonic mass function , especially at the low and high mass extremes . through... |
0901.1880 | r | = 5.5 in we begin the comparison of simulated and observed galaxy properties with the @xmath21 stellar mass functions ( smf ) . in figure [ fig : mf ] we compare the observed ( _ g_-band derived ) smf from @xcite to the smf from our l50/288 simulation . we plot the smf starting from our adopted resolution limit . t... | an efficient `` ejective '' feedback mechanism , such as supernova - driven galactic winds , must reduce the masses of these progenitors before they merge to form today s massive galaxies . feedback must also reduce the masses of lower mass galaxies , which assemble at lower redshifts and have much lower star formation... | we compare the properties of galaxies that form in a cosmological simulation without strong feedback to observations of the galaxy population . we confirm previous findings that models without strong feedback overproduce the observed galaxy baryonic mass function , especially at the low and high mass extremes . through... |
0901.1880 | c | many authors emphasise the overabundance of massive galaxies and their lack of red colours in simulations and sams ( e.g. k05 , @xcite ) and usually blame excessive gas cooling onto central galaxies in massive halos , i.e. hot mode accretion , for this failure . however , in k09 we demonstrated that many galaxies in m... | however , we fail to recover the observed population of passive , low star formation rate galaxies , especially at the high mass end . suppressing all hot mode accretion improves the agreement for high mass galaxies , but it worsens the agreement at intermediate masses . reproducing these observations requires a feedba... | we compare the properties of galaxies that form in a cosmological simulation without strong feedback to observations of the galaxy population . we confirm previous findings that models without strong feedback overproduce the observed galaxy baryonic mass function , especially at the low and high mass extremes . through... |
quant-ph0205177 | i | in 1921 , kaluza @xcite proposed a five dimensional ( 5d ) geometrical framework for the unification of the gravitational and the electromagnetic interactions . following the model of the 4d general relativity , kaluza discussed both the field equations and the particle propagation along 5d time - like geodesics , tryi... | if the 5d metric is independent of the fifth coordinate , then the propagation problem can be reduced to four dimensions by foliation along the fifth coordinate , and we obtain a formulation of 4d quantum mechanics . if the 5d metric is independent of time , we foliate along the time coordinate , and obtain a formulati... | we consider a five dimensional ( 5d ) space - time with a space - like fifth dimension . we implement a quantum formalism by path integrals , and postulate that all the physical information on a 5d massless particle propagation is provided by the statistics over null paths in this 5d space - time . if the 5d metric is ... |
nlin0608015 | i | in recent work , we presented experimental and simulation results for two mutually coupled lasers @xcite with time - delayed asymmetric coupling . the light emitted from one laser propagates through fiber - optic cables to a photodetector that generates an electronic signal proportional to the light - intensity deviati... | we consider a model for two lasers that are mutually coupled optoelectronically by modulating the pump of one laser with the intensity deviations of the other . multiscale perturbation methods are used to describe the amplitude and period of oscillations as a function of the coupling strength and delay time . for weak ... | we consider a model for two lasers that are mutually coupled optoelectronically by modulating the pump of one laser with the intensity deviations of the other . signal propagation time in the optoelectronic loop causes a significant delay leading to the onset of oscillatory output . multiscale perturbation methods are ... |
0811.1458 | i | as a summary , we have considered an exact @xmath0 reflection symmetry in neutrino sector realized at the gut scale in the context of the seesaw model . the exact @xmath0 reflection symmetry has been imposed in the basis where both the charged lepton mass and heavy majorana neutrino mass matrices are real and diagonal ... | we consider an exact reflection symmetry in neutrino sector realized at the gut scale in the context of the seesaw model with and without supersymmetry . assuming the two lighter heavy majorana neutrinos are degenerate at the gut scale , it is shown that the renormalization group ( rg ) evolution from the gut scale to ... | we consider an exact reflection symmetry in neutrino sector realized at the gut scale in the context of the seesaw model with and without supersymmetry . assuming the two lighter heavy majorana neutrinos are degenerate at the gut scale , it is shown that the renormalization group ( rg ) evolution from the gut scale to ... |
1312.6486 | c | we considered @xmath0 photoproduction in ion ion upcs at the lhc and rhic in the coherent and incoherent channels with and without accompanying forward neutron emission and analyzed the role of nuclear gluon shadowing at small @xmath1 , @xmath2 , in these processes . we extended the formalism of leading twist nuclear ... | we consider photoproduction in ion ion ultraperipheral collisions ( upcs ) at the lhc and rhic in the coherent and incoherent quasielastic channels with and without accompanying forward neutron emission and analyze the role of nuclear gluon shadowing at small , , in these processes . we find that despite the good agre... | we consider photoproduction in ion ion ultraperipheral collisions ( upcs ) at the lhc and rhic in the coherent and incoherent quasielastic channels with and without accompanying forward neutron emission and analyze the role of nuclear gluon shadowing at small , , in these processes . we find that despite the good agre... |
1010.5651 | i | due to the diverse features and applications of interconnection networks , it is possible to find many interpretations about network `` optimality '' in the literature . here we are concerned with the following ; see @xcite , @xcite , and ( * ? ? ? _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _... | we consider the bipartite version of the _ degree / diameter problem _ , namely , given natural numbers and , find the maximum number of vertices in a bipartite graph of maximum degree and diameter . in this context , the moore bipartite bound represents an upper bound for . bipartite graphs of maximum degree , diam... | we consider the bipartite version of the _ degree / diameter problem _ , namely , given natural numbers and , find the maximum number of vertices in a bipartite graph of maximum degree and diameter . in this context , the moore bipartite bound represents an upper bound for . bipartite graphs of maximum degree , diam... |
math0703377 | i | solving a general nonlinear optimal control problem ( ocp ) is a difficult challenge , despite powerful theoretical tools are available , e.g. the maximum principle and hamilton - jacobi - bellman ( hjb ) optimality equation . the problem is even more difficult in the presence of state and/or control constraints . stat... | we consider the class of nonlinear optimal control problems ( ocp ) with polynomial data , i.e. , the differential equation , state and control constraints and cost are all described by polynomials , and more generally for ocps with smooth data . in addition , state constraints as well as state and/or action constraint... | we consider the class of nonlinear optimal control problems ( ocp ) with polynomial data , i.e. , the differential equation , state and control constraints and cost are all described by polynomials , and more generally for ocps with smooth data . in addition , state constraints as well as state and/or action constraint... |
cond-mat0001036 | i | the interplay between the electron s spin degree of freedom and the inter - electron interaction has been of interest in the condensed matter physics , in particular in the jellium model where the neutralizing background is taken to be rigid and uniform . the relative strength of the interaction is conventionally measu... | we calculate the charge and the spin density collective modes in random phase approximation ( rpa ) including vertex corrections ( also known as time dependent hartree fock ) , and treating the landau level mixing accurately within the subspace of a single particle hole pair . the feasibility of the experimental observ... | we consider the effect of interactions on electrons confined to two dimensions at landau level filling , with the specific aim to determine the range of parameters where the fully polarized state is stable . we calculate the charge and the spin density collective modes in random phase approximation ( rpa ) including ve... |
1211.1806 | i | the fermi - bose model under study here forms the underlying basis for a range of phenomena in condensed matter and ultra - cold atomic physics . it was proposed in the context of high - temperature superconductivity by friedberg and lee @xcite , and in ultracold gases it corresponds to the theory of resonance superflu... | the problem is solved in spatial dimensions by dividing the system matrix into blocks with generalizations of hankel matrices , here refered to as-block - hankel matrices . the method is practically useful for treating large systems , i.e. dense computational grids or higher spatial dimensions , either on a single stan... | we consider the exponential matrix representing the dynamics of the fermi - bose model in an undepleted bosonic field approximation . a recent application of this model is molecular dimers dissociating into its atomic compounds . the problem is solved in spatial dimensions by dividing the system matrix into blocks with... |
1601.07167 | i | we proposed a scenario where the spin - zero 750 gev state is coupled to a new heavy lepton which lives in the bulk of a higher - dimensional theory and interacts only with the photons of the standard model . we found that they allow for a minimal and compelling explanation of the di - photon resonance via photo - prod... | we propose that the spin - zero state is coupled to a heavy lepton that lives in the bulk of a higher - dimensional theory and interacts only with the photons of the standard model . we compute the di - photon rate in these models with two and more compact extra dimensions and demonstrate that they allow for a compelli... | we consider the phenomenology of a 750 gev resonance which can be produced at the lhc by only photon fusion and subsequently decay into di - photons . we propose that the spin - zero state is coupled to a heavy lepton that lives in the bulk of a higher - dimensional theory and interacts only with the photons of the sta... |
1411.5275 | i | given a discrete structure on a set of elements , a natural question is to be able to locate efficiently the elements using the structure . if the elements are the vertices of a graph , one can use the neighbourhoods of the elements to locate them . in this context , karpovsky , chakrabarty and levitin @xcite have int... | we consider the problem of computing identifying codes of graphs and its fractional relaxation . we focus on vertex - transitive graphs for which we can compute the exact fractional solution . there are known examples of vertex - transitive graphs that reach both bounds . we exhibit infinite families of vertex - transi... | we consider the problem of computing identifying codes of graphs and its fractional relaxation . the ratio between the size of optimal integer and fractional solutions is between 1 and where is the set of vertices of the graph . we focus on vertex - transitive graphs for which we can compute the exact fractional soluti... |
0910.0478 | r | [ sec : discussion ] we show the rest - frame frc for our model with @xmath85 , the b07 star - formation law , and no winds , in figure [ fig : lfirradiorest ] ( _ left panel _ ) as an example . the solid dark red line is the @xmath86 frc . all solid lines assume that starbursts are compact , with @xmath38 . ... | normal galaxies with low star - formation rates become radio - faint at high , because inverse compton ( ic ) losses off the cmb cool cr electrons and positrons rapidly , suppressing their nonthermal radio emission . however , we find that this effect occurs at higher redshifts than previously expected , because escape... | we construct one - zone steady - state models of cosmic ray ( cr ) injection , cooling , and escape over the entire dynamic range of the fir - radio correlation ( frc ) , from normal galaxies to starbursts , over the redshift interval . normal galaxies with low star - formation rates become radio - faint at high , beca... |
0910.0478 | i | we have applied the theory of ltq to predict the frc for redshifts @xmath0 . we use one - zone models of galaxies and starbursts with cr injection , cooling , and escape to predict the equilibrium , steady - state radio spectra of galaxies and starbursts over the entire range of the frc . our goals were to determine ho... | we construct one - zone steady - state models of cosmic ray ( cr ) injection , cooling , and escape over the entire dynamic range of the fir - radio correlation ( frc ) , from normal galaxies to starbursts , over the redshift interval . we find that radio bright submillimeter galaxies alone can not explain the excess r... | we construct one - zone steady - state models of cosmic ray ( cr ) injection , cooling , and escape over the entire dynamic range of the fir - radio correlation ( frc ) , from normal galaxies to starbursts , over the redshift interval . normal galaxies with low star - formation rates become radio - faint at high , beca... |
astro-ph0503435 | c | to quantify the extent of the departure of the local sample from a log - linear relation we have plotted the logarithmic derivatives @xmath14 and @xmath151 of the @xmath12 and @xmath127 relations as a function of @xmath1 and @xmath133 in figure [ fig8 ] . the solid lines show the slopes of the best fit relations . the... | furthermore , assuming no systematic offset , single epoch virial smbh masses estimated for agn ( barth et al . 2005 ) follow the same log - quadratic relation as the local sample , but extend it downward in mass by an order of magnitude . the log - quadratic term in the relation has a significant effect on estimates ... | we demonstrate that a log - linear relation does not provide an adequate description of the correlation between the masses of super - massive black - holes ( smbh , ) and the velocity dispersions of their host spheroid ( ) . an unknown relation between and may be expanded to second order to obtain a log - quadratic rel... |
astro-ph0503435 | c | using the local sample of smbhs we have demonstrated that the parameter describing a log - linear fit to the @xmath12 relation is sensitive to the inclusion of individual galaxies at a level larger than the statistical uncertainty . this indicates that a log - linear @xmath12 relation does not provide a good descriptio... | we demonstrate that a log - linear relation does not provide an adequate description of the correlation between the masses of super - massive black - holes ( smbh , ) and the velocity dispersions of their host spheroid ( ) . we find unbiased parameter estimates of , and . at the 80% level / skm / s the logarithmic slop... | we demonstrate that a log - linear relation does not provide an adequate description of the correlation between the masses of super - massive black - holes ( smbh , ) and the velocity dispersions of their host spheroid ( ) . an unknown relation between and may be expanded to second order to obtain a log - quadratic rel... |
1204.6532 | i | relativistic plasmas at extremely high temperature @xmath1 such as electron and/or quark - gluon plasma are expected to be realized in the early universe and the experiments of heavy ion collisions at relativistic heavy ion collider and large hadron collider . these systems have multi - energy scale at weak coupling ( ... | we derive a linearized kinetic equation for fermionic excitations with an ultrasoft momentum , , from the kadanoff - baym equation in a yukawa model and quantum electrodynamics ( qed ) at extremely high , where is the coupling constant . we show that this equation is equivalent to the self - consistent equation in the ... | we derive a linearized kinetic equation for fermionic excitations with an ultrasoft momentum , , from the kadanoff - baym equation in a yukawa model and quantum electrodynamics ( qed ) at extremely high , where is the coupling constant . we show that this equation is equivalent to the self - consistent equation in the ... |
0804.2179 | c | we have described an implementation of the nanomechanical quantum superposition generation and verification scheme presented in the companion reference @xcite . the implementation is based on the circuit qed set - up with the incorporation of a mechanical degree of freedom formed out of a suspended squid loop segment ... | we describe a possible implementation of the nanomechanical quantum superposition generation and detection scheme described in the preceding , companion paper [ armour a d and blencowe m p 2008 _ new . the implementation is based on the circuit quantum electrodynamics ( qed ) set - up , with the addition of a mechanica... | we describe a possible implementation of the nanomechanical quantum superposition generation and detection scheme described in the preceding , companion paper [ armour a d and blencowe m p 2008 _ new . j. phys . _ * xx * xxx ] . the implementation is based on the circuit quantum electrodynamics ( qed ) set - up , with ... |
astro-ph0503119 | c | we have described algorithms that identify and extract self - absorption ( hisa ) features in high - resolution 21 cm line data cubes . these algorithms were designed to carry out a hisa survey of cold in the initial @xmath239 phase of the arcminute - resolution canadian galactic plane survey ( cgps ) , but they sho... | we describe algorithms that detect 21 cm line self - absorption ( hisa ) in large data sets and extract it for analysis . our search method identifies hisa as spatially and spectrally confined dark features that appear as negative residuals after removing larger - scale emission components with a modified clean algor... | we describe algorithms that detect 21 cm line self - absorption ( hisa ) in large data sets and extract it for analysis . our search method identifies hisa as spatially and spectrally confined dark features that appear as negative residuals after removing larger - scale emission components with a modified clean algor... |
1202.3997 | i | type ia supernovae ( sne ia ) are among the most energetic explosions in the known universe , releasing @xmath1 ergs of kinetic energy in their ejecta , and synthesizing @xmath2 @xmath3 of radioactive @xmath0ni . the discovery of the phillips relation @xcite has enabled the use of sne ia as standardizable cosmologi... | we describe the detonation mechanism comprising the `` pulsationally assisted '' gravitationally confined detonation ( gcd ) model of type ia supernovae ( sne ia ) . this model is analogous to the previous gcd model reported in ; however , the chosen initial conditions produce a substantively different detonation mech... | we describe the detonation mechanism comprising the `` pulsationally assisted '' gravitationally confined detonation ( gcd ) model of type ia supernovae ( sne ia ) . this model is analogous to the previous gcd model reported in ; however , the chosen initial conditions produce a substantively different detonation mech... |
1202.3997 | r | we extended the study of the gcd model described in j08with two primary differences . first , we included detonation physics in the simulations ( as we described in sections [ subsec : numreal ] and [ sec : methods ] ) and followed the models from ignition , through the detonation phase , and to the free expansion phas... | the amount of energy released during the deflagration phase is enough to cause the star to rapidly expand , so that when the ash reaches the antipodal point , the surface density is too low to initiate a detonation . the stellar contraction acts to increase the density of the star , including the density in the collisi... | we describe the detonation mechanism comprising the `` pulsationally assisted '' gravitationally confined detonation ( gcd ) model of type ia supernovae ( sne ia ) . this model is analogous to the previous gcd model reported in ; however , the chosen initial conditions produce a substantively different detonation mech... |
1202.3997 | c | we have conducted a series of numerical experiments simulating the evolution of a wd star in which we initiate a deflagration at off - center ignition points . the amount of energy released during the deflagration phase is enough to cause the star to undergo an energetic pulsation . as in the classical gcd model , the ... | the ash breaks out of the surface of the white dwarf , flows laterally around the star , and converges on the collision region at the antipodal point from where it broke out . we characterized the simulations by the energy released during the deflagration phase , which ranged from 38% to 78% of the white dwarf s bindin... | we describe the detonation mechanism comprising the `` pulsationally assisted '' gravitationally confined detonation ( gcd ) model of type ia supernovae ( sne ia ) . this model is analogous to the previous gcd model reported in ; however , the chosen initial conditions produce a substantively different detonation mech... |
1501.05954 | i | one of the most prominent characteristics of the ultraviolet ( uv ) , optical , and near - infrared ( nir ) spectra of active galactic nuclei ( agns ) is the presence of broad emission lines . while we know that these features arise on scales not much larger than the accretion disk , their physical nature remains one o... | the variations of all the strong emission lines lag behind those of the continuum , with heii lagging behind the continuum bydays and ly , civ , and siiv lagging bydays . the relationship between the continuum and emission lines is complex . in particular , during the second half of the campaign , all emission - line l... | we describe the first results from a six - month long reverberation - mapping experiment in the ultraviolet based on 171 observations of the seyfert 1 galaxy ngc 5548 with the cosmic origins spectrograph on the _ hubble space telescope_. significant correlated variability is found in the continuum and broad emission l... |
1202.4372 | i | the thermal control of a spacecraft ensures that the temperatures of its various parts are kept within their appropriate ranges @xcite . the simulation and prediction of temperatures in a spacecraft during a mission are usually carried out by commercial software packages . these software packages employ `` lumped param... | we develop a linear method for solving the nonlinear differential equations of a lumped - parameter thermal model of a spacecraft moving in a closed orbit . our method , based on perturbation theory , is compared with heuristic linearizations of the same equations . we apply our method to a minimal thermal model of a s... | we develop a linear method for solving the nonlinear differential equations of a lumped - parameter thermal model of a spacecraft moving in a closed orbit . our method , based on perturbation theory , is compared with heuristic linearizations of the same equations . the essential feature of the linear approach is that ... |
1202.4372 | i | we have studied the evolution of the thermal state of an orbiting spacecraft and developed a linear approach to this problem that is based on a rigorous perturbative treatment of the exact nonlinear equations . the first - order perturbation equations , eqs . ( [ linode - pert ] ) , constitute the basic linear system ,... | the essential feature of the linear approach is that it provides a decomposition in thermal modes , like the decomposition of mechanical vibrations in normal modes . the stationary periodic solution of the linear equations can be alternately expressed as an explicit integral or as a fourier series . we briefly study th... | we develop a linear method for solving the nonlinear differential equations of a lumped - parameter thermal model of a spacecraft moving in a closed orbit . our method , based on perturbation theory , is compared with heuristic linearizations of the same equations . the essential feature of the linear approach is that ... |
astro-ph0204055 | i | the masses of galaxies are traditionally estimated by dynamical methods from the kinematics of their stars and gas . ever since extended hi rotation curves were first measured for spirals , it has been clear that the implied masses include not only the observed material , but also substantial amounts of dark matter . i... | a comparison with broad band photometry then yields estimates of dust attenuation and of stellar mass . the distribution of d(4000 ) is strongly bimodal , showing a clear division between galaxies dominated by old stellar populations and galaxies with more recent star formation . -0.55 + _ box 208121 , new haven , c... | we develop a new method to constrain the star formation histories , dust attenuation and stellar masses of galaxies . it is based on two stellar absorption line indices , the 4000 break strength and the balmer absorption line index h . together , these indices allow us to constrain the mean stellar ages of galaxies an... |
astro-ph0204055 | i | we have developed a new method to constrain the past star formation histories of galaxies . it is based on two stellar absorption line indices , the 4000 break strength d@xmath6(4000 ) and the balmer absorption line index h@xmath0 . together these two indices allow us to place constraints on the mean age of the stella... | we develop a new method to constrain the star formation histories , dust attenuation and stellar masses of galaxies . it is based on two stellar absorption line indices , the 4000 break strength and the balmer absorption line index h . together , these indices allow us to constrain the mean stellar ages of galaxies an... | we develop a new method to constrain the star formation histories , dust attenuation and stellar masses of galaxies . it is based on two stellar absorption line indices , the 4000 break strength and the balmer absorption line index h . together , these indices allow us to constrain the mean stellar ages of galaxies an... |
1010.1264 | i | in a sense , ads / cft duality reduces the construction of quantum gravity to a solved problem . gravity is written in terms of a nongravitational quantum field theory @xcite , and the technology of wilson @xcite can then be applied . in its current form , this duality reports only the measurements made by an externa... | we develop parallels between the holographic renormalization group in the bulk and the wilsonian renormalization group in the dual field theory . our philosophy differs from most previous work on the holographic rg ; the most notable feature is the key role of multi - trace operators . we work out the forms of various ... | we develop parallels between the holographic renormalization group in the bulk and the wilsonian renormalization group in the dual field theory . our philosophy differs from most previous work on the holographic rg ; the most notable feature is the key role of multi - trace operators . we work out the forms of various ... |
gr-qc0604058 | i | it is by now well established that the physics associated with classical and quantum fields in curved spacetimes can be reproduced , within certain approximations , in a variety of different physical systems the so - called `` analogue models of general relativity ( gr ) '' @xcite . the simplest example of such a sys... | it is sufficient to set up a dynamically changing flow _ either _ eventually generating an arbitrarily small sonic region , but without any ergoregion , _ or _ even just asymptotically , in laboratory time , approaching a sonic regime with sufficient rapidity . pacs : 04.20.gz , 04.62.+v , 04.70.-s , 04.70.dy , 04.80.c... | we discuss the issue of quasi - particle production by `` analogue black holes '' with particular attention to the possibility of reproducing hawking radiation in a laboratory . by constructing simple geometric acoustic models , we obtain a somewhat unexpected result : we show that in order to obtain a stationary and p... |
astro-ph0212205 | i | it has long been realized that galaxies , and self - gravitating systems in general , follow a kind of organization despite the diversity of their initial conditions and their environement . this organization is illustrated by morphological classification schemes such as the hubble sequence and by simple rules which go... | , the system is expected to reach an equilibrium state of a fermi - dirac type within a few dynamical times . we describe in detail the equilibrium phase diagram and the nature of phase transitions which occur in self - gravitating systems . these relaxation equations , of a generalized fokker - planck type , are deriv... | we discuss the statistical mechanics of violent relaxation in stellar systems following the pioneering work of lynden - bell ( 1967 ) . the solutions of the gravitational vlasov - poisson system develop finer and finer filaments so that a statistical description is appropriate to smooth out the small - scales and descr... |
physics9910025 | r | we have carried out a series of experiments to determine the statistical characteristics of the dark , maintained , and driven neural discharge in cat rgc and lgn cells . using the analysis techniques presented in sec . [ sec : analysis ] , we compare and contrast the neural activity for these three different stimulus ... | a drifting - grating stimulus yields rgc and lgn driven spike trains similar in character to those observed in the maintained discharge , with two notable distinctions : action potentials are reorganized along the time axis so that they occur only during certain phases of the stimulus waveform , and fractal activity is... | we employ a number of statistical measures to characterize neural discharge activity in cat retinal ganglion cells ( rgcs ) and in their target lateral geniculate nucleus ( lgn ) neurons under various stimulus conditions , and we develop a new measure to examine correlations in fractal activity between spike - train pa... |
physics9910025 | c | the presence of a stimulus alters the manner in which spike trains in the visual system exhibit fractal behavior . in the absence of a stimulus , rgc and lgn dark discharges display similar fractal activity ( see fig . the normalized rate functions of the two recordings , when computed for long counting times , follow ... | the presentation of a constant , uniform luminance to the eye reduces the fractal fluctuations in the rgc maintained discharge but enhances them in the target lgn discharge , so that neural activity in the pair no longer mirror each other . , the discharges of pairs of lgn cells are highly correlated over long time sca... | we employ a number of statistical measures to characterize neural discharge activity in cat retinal ganglion cells ( rgcs ) and in their target lateral geniculate nucleus ( lgn ) neurons under various stimulus conditions , and we develop a new measure to examine correlations in fractal activity between spike - train pa... |
astro-ph0004309 | i | galaxy clusters are the youngest and largest organized structures in the universe , and as such provide us with a wealth of cosmological information . the most massive clusters draw their substance from cosmologically significant volumes of linear scale @xmath7 mpc . these scales are large enough that no known coherent... | we employ an ensemble of 24 hydrodynamic cluster simulations to create spatially and spectrally resolved images of quality comparable to _ chandra _ s expected performance . emission from simulation mass elements is represented using the xspec ` m`ekal program assuming 0.3 solar metallicity and the resulting spectra ar... | we employ an ensemble of 24 hydrodynamic cluster simulations to create spatially and spectrally resolved images of quality comparable to _ chandra _ s expected performance . emission from simulation mass elements is represented using the xspec ` m`ekal program assuming 0.3 solar metallicity and the resulting spectra ar... |
astro-ph0211175 | i | in the absence of gradients of velocity and magnetic field in the resolution element , the polarization emerging from an atmosphere must be either symmetric or antisymmetric with respect to the central wavelength of each spectral line ( e.g. , @xcite @xcite ; @xcite @xcite ) . the polarization observed in the solar pho... | we employ the magnetic and velocity fields from turbulent dynamo simulations to synthesize the polarization of a typical photospheric line . the simulated magnetograms present a level of signal similar to that of the inter - network regions . this deficit may reflect the fact that the reynolds numbers of the numerical ... | we employ the magnetic and velocity fields from turbulent dynamo simulations to synthesize the polarization of a typical photospheric line . the synthetic stokes profiles have properties in common with those observed in the quiet sun . the simulated magnetograms present a level of signal similar to that of the inter - ... |
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