Research archive
arXiv papers from February 2006
The most recent 100 records published that month. Open any paper for its original abstract, citation metadata, related research, and reading tools.
Denis Gaidashev, Michael Yampolsky
We study one of the central open questions in one-dimensional renormalization theory -- the conjectural universality of golden-mean Siegel disks. We present an approach to the problem based on cylinder renormalization proposed by the second author. Numerical implementation of this approach relies on the Constructive Measurable Riemann Mapping Theorem proved
Diego Dominici
We present the history and previous approaches to the proof of Stirling's series. We use a different procedure, based on the asymptotic analysis of the difference equation $\Gamma(z+1)=z\Gamma(z)$. The method reproduces Stirling's series very easily and can be extended to use in more complicated difference equations.
- Rejecting Astrophysical False Positives from the TrES Transiting Planet Survey: The Example of GSC 03885-00829astro-ph
Francis T. O'Donovan, David Charbonneau, Guillermo Torres, Georgi Mandushev
Ground-based wide-field surveys for nearby transiting gas giants are yielding far fewer true planets than astrophysical false positives, of which some are difficult to reject. Recent experience has highlighted the need for careful analysis to eliminate astronomical systems where light from a faint eclipsing binary is blended with that from a bright star. Dur
Israel Klich, Gil Refael, Alessandro Silva
We explore the relation between entanglement entropy of quantum many body systems and the distribution of corresponding, properly selected, observables. Such a relation is necessary to actually measure the entanglement entropy. We show that in general, the Shannon entropy of the probability distribution of certain symmetry observables gives a lower bound to
Michael Endl, William D. Cochran, Robert A. Wittenmyer, Artie P. Hatzes
We present the precise radial velocity (RV) data for the metal-rich star HD 45350 collected with the Harlan J. Smith (HJS) 2.7 m telescope and the Hobby-Eberly Telescope (HET) at McDonald Observatory. This star was noticed by us as a candidate for having a giant planetary companion in a highly eccentric orbit, but the lack of data close to periastron left th
L. Ludovici, K. S. McFarland, M. Shiozawa, G. P. Zeller
We summarize the discussion and presentation of new experimental results in low energy neutrino scattering at the NuInt05 workshop. In addition, we comment on several investigations that should be targeted in preparation for the next NuInt workshop.
Peter B. Weichman
An experiment is proposed to test a previously developed theory of the hydrodynamics of a nonequilibrium heat current-induced superfluid-normal interface. It is shown that the interfacial ``trapped'' second sound mode predicted by the theory leads to a sharp resonant dip in the reflected signal from an external second sound pulse propagated towards the inter
- Strongly Inhomogeneous Phases and Non-Fermi Liquid Behavior in Randomly Depleted Kondo Latticescond-mat.str-el
Ribhu K. Kaul, Matthias Vojta
We investigate the low-temperature behavior of Kondo lattices upon random depletion of the local $f$-moments, by using strong-coupling arguments and solving SU($N$) saddle-point equations on large lattices. For a large range of intermediate doping levels, between the coherent Fermi liquid of the dense lattice and the single-impurity Fermi liquid of the dilut
G. P. Zeller
This paper summarizes new experimental results in low energy neutrino cross sections as presented in the neutrino scattering working group at the NuFact05 workshop. Several questions and directives for future NuFact workshops are also outlined.
Qi Cheng
Let $k$ and $n$ be positive integers, $n>k$. Define $r(n,k)$ to be the minimum positive value of $$ |\sqrt{a_1} + ... + \sqrt{a_k} - \sqrt{b_1} - >... -\sqrt{b_k} | $$ where $ a_1, a_2, ..., a_k, b_1, b_2, ..., b_k $ are positive integers no larger than $n$. It is an important problem in computational geometry to determine a good upper bound of $-\log r(n,k)
Peter A. Milne
The SPI instrument on-board the ESA/INTEGRAL satellite is engaged in a mission-long study of positron annihilation radiation from the Galaxy. Early results suggest that the disk component is only weakly detected at 511 keV by SPI. We review CGRO/OSSE, TGRS and SMM studies of 511 keV line and positronium continuum emission from the Galaxy in light of the earl
D. Mukherjee, A. Varchenko
We fix three natural numbers $k, n, N$, such that $n+k+1=N$, and introduce the notion of two dual arrangements of hyperplanes. One of the arrangements is an arrangement of $N$ hyperplanes in a $k$-dimensional affine space, the other is an arrangement of $N$ hyperplanes in an $n$-dimensional affine space. We assign weights $\al_1, ..., \al_N$ to the hyperplan
Elizabeth Dan-Cohen, Ivan Penkov, Noah Snyder
Root-reductive Lie algebras are direct limits of finite-dimensional reductive Lie algebras under injections which preserve the root spaces. It is known that a root-reductive Lie algebra is a split extension of an abelian Lie algebra by a direct sum of copies of finite-dimensional simple Lie algebras as well as copies of the three simple infinite-dimensional
Antonio Di Lorenzo
We analyze the issue of the interpretation of the wavefunction, namely whether it should be interpreted as describing individual systems or ensembles of identically prepared systems. We propose an experiment which can decide the issue, based on the simultaneous measurement of the same observable with different detectors, and we discuss the theoretical implic
- Orbital Interaction Mechanisms of Conductance Enhancement and Rectification by Dithiocarboxylate Anchoring Groupcond-mat.mtrl-sci
Zhenyu Li, D. S. Kosov
We study computationally the electron transport properties of dithiocarboxylate terminated molecular junctions. Transport properties are computed self-consistently within density functional theory and nonequilibrium Green's functions formalism. A microscopic origin of the experimentally observed current amplification by dithiocarboxylate anchoring groups is
Shinsei Ryu, Tadashi Takayanagi
A holographic derivation of the entanglement entropy in quantum (conformal) field theories is proposed from AdS/CFT correspondence. We argue that the entanglement entropy in d+1 dimensional conformal field theories can be obtained from the area of d dimensional minimal surfaces in AdS_{d+2}, analogous to the Bekenstein-Hawking formula for black hole entropy.
G. Duchene, E. Delgado-Donate, K. Haisch, L. Loinard
It has now been known for over a decade that low-mass stars located in star-forming regions are very frequently members of binary and multiple systems, even more so than main sequence stars in the solar neighborhood. This high multiplicity rate has been interpreted as the consequence of the fragmentation of small molecular cores into a few seed objects that
S. R. Doty, R. M. Green
We obtain a presentation of certain affine q-Schur algebras in terms of generators and relations. The presentation is obtained by adding more relations to the usual presentation of the quantized enveloping algebra of type affine gl_n. Our results extend and rely on the corresponding result for the q-Schur algebra of the symmetric group, which were proved by
Shmuel Friedland, Elliot Krop, Per Hakan Lundow, Klas Markström
In this paper we review the asymptotic matching conjectures for $r$-regular bipartite graphs, and their connections in estimating the monomer-dimer entropies in $d$-dimensional integer lattice and Bethe lattices. We prove new rigorous upper and lower bounds for the monomer-dimer entropies, which support these conjectures. We describe a general construction o
D. Napoletani, D. C. Struppa, T. Sauer, V. Morozov
In this article, we describe a new method of extracting information from signals, called functional dissipation, that proves to be very effective for enhancing classification of high resolution, texture-rich data. Our algorithm bypasses to some extent the need to have very specialized feature extraction techniques, and can potentially be used as an intermedi
Alessio Del Fabbro, Roberto Chignola, Edoardo Milotti
The simulation of many-particle systems often requires the detailed knowledge of proximity relations to reduce computational complexity and to provide a basis for specific calculations. Here we describe the basic scheme of a simulator of tumor spheroid growth: the calculation of mechanical interactions between cells and of the concentrations of diffusing che
W. H. T. Vlemmings, P. J. Diamond, H. Imai
Planetary nebulae often have asymmetric shapes, which could arise due to collimated jets from evolved stars before evolution to the planetary nebula phase. The source of jet collimation in these stars is unknown. Magnetic fields are thought to collimate outflows that are observed in many other astrophysical sources, such as active galactic nuclei and proto-s
G. A. Benesh, Anzhong Wang
All homothetic self-similar solutions of the Brans-Dicke scalar field in three-dimensional spacetime with circular symmetry are found in closed form.
C. del Burgo, L. Cambresy
We present ISOPHOT observations between 60 and 200 microns and a near-infrared extinction map of LDN 1780. We have used the ISOPHOT data together with the 25, 60 and 100 microns IRIS maps to disentangle the warm and cold components of large dust grains that are observed in translucent and dense clouds. The warm and cold components in LDN 1780 have different
H. M. Antia, Sarbani Basu
The recent downward revision of solar photospheric abundances of Oxygen and other heavy elements has resulted in serious discrepancies between solar models and solar structure as determined through helioseismology. In this work we investigate the possibility of determining the solar heavy-element abundance without reference to spectroscopy by using helioseis
Peter Langfelder
We revisit the energy transfer necessary for the warped reheating scenario in a two-throat geometry. We study KK mode wavefunctions of the full two-throat system in the Randall--Sundrum (RS) approximation and find an interesting subtlety in the calculation of the KK mode tunnelling rate. While wavepacket tunnelling is suppressed unless the Standard Model thr
J. M. Miller, J. Homan, D. Steeghs, M. Rupen
We present the first results of coordinated multi-wavelength observations of the Galactic black hole GX 339-4 in a canonical low-hard state, obtained during its 2004 outburst. XMM-Newton observed the source for 2 revolutions, or approximately 280 ksec; RXTE monitored the source throughout this long stare. The resulting data offer the best view yet obtained o
M. O. Wascko
MiniBooNE began running in antineutrino mode on 19 January, 2006. We describe the sensitivity of MiniBooNE to LSND-like nuebar oscillations and outline a program of antineutrino cross-section measurements necessary for the next generation of neutrino oscillation experiments. We describe three independent methods of constraining wrong-sign (neutrino) backgrou
M. O. Wascko
We present MiniBooNE's preliminary numu charged-current single pion (CC1pi) cross section measurement, calculated using the ratio to charge current quasi-elastic (CCQE) events. We find the inclusive CC1pi cross section to be below the predcition of the NUANCE and NEUGEN Monte Carlos.
Jeff Tollaksen
By analyzing the concept of contextuality (Bell-Kochen-Specker) in terms of pre-and-post-selection (PPS), it is possible to assign definite values to observables in a new and surprising way. Physical reasons are presented for restrictions on these assignments. When measurements are performed which do not disturb the pre- and post-selection (i.e. weak measure
- The Casimir effect for a sphere and a cylinder in front of plane and corrections to the proximity force theoremhep-th
M. Bordag
Using a path integral approach we rederive a recently found representation of the Casimir energy for a sphere and a cylinder in front of a plane and derive the first correction to the proximity force theorem.
G. B. Taylor, N. E. Gugliucci, A. C. Fabian, J. S. Sanders
We present Very Long Baseline Array (VLBA) observations of the nucleus of NGC 1275, the central, dominant galaxy in the Perseus cluster of galaxies. These are the first observations to resolve the linearly polarized emission from 3C84, and from them we determine a Faraday rotation measure (RM) ranging from 6500 to 7500 rad/m^2 across the tip of the bright so
Michael Yampolsky
In this note we construct hyperbolic fixed points for cylinder renormalization of maps with Siegel disks.
Yong-Seon Song
The large scale structure formation in the standard Einstein gravity at later time is uniquely determined by the expansion history H(z) measured by the geometrical factor. A possible departure from the expected standard structure formation is detectable by growth structure test. We design new deviation parameters to test standard gravity at large scales and
Stanley J. Brodsky, Guy F. de Teramond
We show how the string amplitude $\Phi(z)$ defined on the fifth dimension in AdS$_5$ space can be precisely mapped to the light-front wavefunctions of hadrons in physical spacetime. We find an exact correspondence between the holographic variable $z$ and an impact variable $\zeta$, which represents the measure of transverse separation of the constituents wit
H. Ibrahim, M. H. van Emden
Functional programming comes in two flavours: one where ``functions are first-class citizens'' (we call this applicative) and one which is based on equations (we call this declarative). In relational programming clauses play the role of equations. Hence Prolog is declarative. The purpose of this paper is to provide in relational programming a mathematical ba
- Is the dark matter interpretation of the EGRET gamma excess compatible with antiproton measurements?astro-ph
Lars Bergstrom, Joakim Edsjo, Michael Gustafsson, Pierre Salati
We investigate the internal consistency of the halo dark matter model which has been proposed by de Boer et al. to explain the excess of diffuse galactic gamma rays observed by the EGRET experiment. Any model based on dark matter annihilation into quark jets, such as the supersymmetric model proposed by de Boer et al., inevitably also predicts a primary flux
Yuliya P. Moskaleva, Yurii S. Samoilenko
Methods of *-representations in Hilbert space are applied to study of systems of $n$ subspaces in a linear space. It is proved that the problem of description of $n$-transitive subspaces in a finite-dimensional linear space is *-wild for $n \geq 5$.
- Quantum oscillations of the rectified voltage and the critical current of asymmetric mesoscopic superconducting loopscond-mat.supr-con
V. L. Gurtovoi, S. V. Dubonos, A. V. Nikulov, N. N. Osipov
The current-voltage curves and magnetic dependence of the critical current of asymmetric superconducting loops are measured. It was found that sign and value of the asymmetry of the current-voltage curves changes with value of magnetic field, periodically for single loop and system of identical loops. The obtained results allow to explain the quantum oscilla
- Impurity effects on optical response in a finite band electronic system coupled to phononscond-mat.mtrl-sci
Anton Knigavko, J. P. Carbotte
The concepts, which have traditionally been useful in understanding the effects of the electron--phonon interaction in optical spectroscopy, are based on insights obtained within the infinite electronic band approximation and no longer apply in finite band metals. Impurity and phonon contributions to electron scattering are not additive and the apparent stre
- Matters of Gravity, The Newsletter of The Topical Group in Gravitation of the American Physical Society, Volume 27, Spring 2006gr-qc
Jorge Pullin
GGR News: GGR program at the APS April meeting in Dallas We hear that..., 100 years ago, by Jorge Pullin Research Briefs: What's new in LIGO, by David Shoemaker LISA Pathfinder, by Paul McNamara Recent progress in binary black hole simulations, by Thomas Baumgarte Conference reports: Workshop on Emergence of Spacetime, by Olaf Dreyer Quantum gravity subprogr
David Berenstein, Samuel Pinansky
We study superpotential perturbations of q deformed N=4 Yang-Mills for q a root of unity. This is a special case whose geometry is associated to an orbifold with three lines of codimension two singularities meeting at the origin. We perform field theory perturbations that leave only co-dimension three singularities of conifold type in the geometry. We show t
Louis Crane
We explore the possibility of replacing point set topology by higher category theory and topos theory as the foundation for quantum general relativity. We discuss the BC model and problems of its interpretation, and connect with the construction of causal sites.
Emilio Musso, Lorenzo Nicolodi
This article addresses the question of involutiveness and discusses the initial value problem for a class of overdetermined systems of partial differential equations which arise in the theory of integrable systems and are defined by tableaux.
S. Fornasier, I. Belskaya, M. Fulchignoni, M. A. Barucci
We present the first albedo determination of 2867 Steins, the asteroid target o f the Rosetta space mission together with 21 Lutetia. The data were obtained in polarimetric mode at the ESO-VLT telescope with the FORS1 instrument in the V and R filters. Observations were carried out from Jun e to August 2005 covering the phase angle range from 10.3 deg. to 28
M. H. van Emden
Semantics of logic programs has been given by proof theory, model theory and by fixpoint of the immediate-consequence operator. If clausal logic is a programming language, then it should also have a compositional semantics. Compositional semantics for programming languages follows the abstract syntax of programs, composing the meaning of a unit by a mathemat
John A. Robertson, Steven A. Kivelson, Eduardo Fradkin, Alan C. Fang
In two dimensions, quenched disorder always rounds transitions involving the breaking of spatial symmetries so, in practice, it can often be difficult to infer what form the symmetry breaking would take in the ``ideal,'' zero disorder limit. We discuss methods of data analysis which can be useful for making such inferences, and apply them to the problem of d
N. S. Skantzos, J. P. L. Hatchett
We study the Lebwohl-Lasher model for systems in which spin are arranged on random graph lattices. At equilibrium our analysis follows the theory of spin-systems on random graphs which allows us to derive exact bifurcation conditions for the phase diagram. We also study the dynamics of this model using a variant of the dynamical replica theory. Our results a
E. V. Gorbar, Michio Hashimoto, V. A. Miransky, I. A. Shovkovy
We study the spectrum of light plasmons in the (gapped and gapless) two-flavor color superconducting phases and its connection with the chromomagnetic instabilities and the structure of the ground state. It is revealed that the chromomagnetic instabilities in the 4-7th and 8th gluonic channels correspond to two very different plasmon spectra. These spectra l
- Coverage dependence of the 1-propanol adsorption on the Si(001) surface and fragmentation dynamicscond-mat.mtrl-sci
Jian-Ge Zhou, Frank Hagelberg, Chuanyun Xiao
The geometric, electronic, energetic, and dynamic properties of 1-propanol adsorbed on the Si(001)-2x1 surface are studied from first principles by use of a slab approach. The 1-propanol molecule initially interacts with the Si surface through formation of a dative bond, subsequently the physisorbed 1-propanol molecule reacts with the surface by cleavage of
G. Pace, A. Recio-Blanco, G. Piotto, Y. Momany
We present metallicity measurements of 25 stars in the blue horizontal branch of the Galactic globular cluster NGC 2808. Our measurements are based on moderate-resolution spectra taken with the multi-object fiber facility FLAMES-UVES, mounted on Kueyen at the Very Large Telescope. We confirm that stars hotter than a threshold temperature have super-solar abu
Askold Duviryak
By using symmetry properties, the two-body Dirac equation in coordinate representation is reduced to the coupled pair of radial second-order differential equations. Then the large-j expansion technique is used to solve a bound state problem. Linear-plus-Coulomb potentials of different spin structure are examined in order to describe the asymptotic degeneracy
Naoki Yamamoto
In the theory of quantum dynamical filtering, one of the biggest issues is that the underlying system dynamics represented by a quantum stochastic differential equation must be known exactly in order that the corresponding filter provides an optimal performance; however, this assumption is generally unrealistic. Therefore, in this paper, we consider a class
Marta Volonteri
Supermassive black holes (SMBHs) are nowadays believed to reside in most local galaxies, and the available data show an empirical correlation between bulge luminosity - or stellar velocity dispersion - and black hole mass, suggesting a single mechanism for assembling black holes and forming spheroids in galaxy halos. The evidence is therefore in favour of a
Massimiliano Esposito, Shaul Mukamel
A quantum fluctuation theorem for a driven quantum subsystem interacting with its environment is derived based solely on the assumption that its reduced density matrix obeys a closed evolution equation i.e. a quantum master equation (QME). Quantum trajectories and their associated entropy, heat and work appear naturally by transforming the QME to a time depe
B. Alles, M. D'Elia
We review the method developed in Pisa to determine the topological susceptibility in lattice QCD and present a collection of new and old results obtained by the method.
Thierry Sousbie, Christophe Pichon, Hélène Courtois, Stéphane Colombi
The length of the three-dimensional filaments observed in the fourth public data-release of the SDSS is measured using the {\em local skeleton} method. It consists in defining the set of points where the gradient of the smoothed density field is extremal along its isocontours, with some additional constraints on local curvature to probe actual ridges in the
- Application of the Gel'fand Matrix Method to the Missing Label Problem in Classical Kinematical Lie Algebrasmath-ph
Rutwig Campoamor-Stursberg
We briefly review a matrix based method to compute the Casimir operators of Lie algebras, mainly certain type of contractions of simple Lie algebras. The versatility of the method is illustrated by constructing matrices whose characteristic polynomials provide the invariants of the kinematical algebras in (3+1)-dimensions. Moreover it is shown, also for kine
Raanan Schul
We study one dimensional sets (Hausdorff dimension) lying in a Hilbert space. The aim is to classify subsets of Hilbert spaces that are contained in a connected set of finite Hausdorff length. We do so by extending and improving results of Peter Jones and Kate Okikiolu for sets in $\R^d$. Their results formed the basis of quantitative rectifiability in $\R^d
Farhan Saif, Mauro Fortunato
We calculate the quantum revival time for a wave-packet initially well localized in a one-dimensional potential in the presence of an external periodic modulating field. The dependence of the revival time on various parameters of the driven system is shown analytically. As an example of application of our approach, we compare the analytically obtained values
Agustin Sabio Vera
Azimuthal angle decorrelation in inclusive dijet cross sections is studied analytically to take into account the next-to-leading corrections to the BFKL kernel while keeping the jet vertices at leading order. The spectral representation on the basis of leading order eigenfunctions is generalized to include the dependence on conformal spins. With this procedu
Marco M. Caldarelli
We review the issue of chronology protection and show how string theory can solve it in the half BPS sector of AdS/CFT. According to the LLM prescription, half BPS excitations of AdS_5 x S^5 geometries in type IIB string theory can be mapped into free fermion configurations. We show that unitarity of the theory describing these fermions is intimately related
Shahrokh Parvizi, Alireza Tavanfar
In this note, we propose the free energy of general \emph{non-supersymmetric} black hole attractors arising in type IIA(B) superstrings on 3-fold Calabi-Yau, in the supergravity limit. This, by definition, differs from its counterpart BPS free energy by a factor of $4 $. Correspondingly, a mixed ensemble for these black holes is proposed.
P. Serra, S. C. Trager, J. M. van der Hulst, T. A. Oosterloo
We present the result of radio and optical observations of the S0 galaxy IC 4200. We find that the galaxy hosts 8.5 billion solar masses of HI rotating on a ~90 deg warped disk extended out to 60 kpc from the centre of the galaxy. Optical spectroscopy reveals a simple-stellar-population-equivalent age of 1.5 Gyr in the centre of the galaxy and V- and R-band
S. C. Chapman, R. Ibata, G. F. Lewis, A. M. N. Ferguson
We present evidence for a metal-poor, [Fe/H]$\sim-1.4$ $\sigma$=0.2 dex, stellar halo component detectable at radii from 10 kpc to 70 kpc, in our nearest giant spiral neighbor, the Andromeda galaxy. This metal-poor sample underlies the recently-discovered extended rotating component, and has no detected metallicity gradient. This discovery uses a large sampl
D. V. Zakharov, J. Deisenhofer, H. -A. Krug von Nidda, P. Lunkenheimer
We present detailed ESR investigations on single crystals of the low-dimensional quantum magnet TiOCl. The anisotropy of the g-factor indicates a stable orbital configuration below room temperature, and allows to estimate the energy of the first excited state as 0.3(1) eV ruling out a possible degeneracy of the orbital ground state. Moreover, we discuss the
Juan R. Cortes, Jeffrey D. P. Kenney, Eduardo Hardy
We present the results of the stellar and ionized gas kinematics of 13 bright peculiar Virgo cluster galaxies. The stellar velocity field are mostly consistent with a rotation pattern, but some of them shows interesting features such as; S-shaped stellar isovelocity contours in NGC 4064, and signatures of kinematical distinct components in NGC 4429, and NGC
Francesca C. Chittaro
In the paper we present a generalization to Hamiltonian flows on symplectic manifolds of the estimate proved by Ballmann and Wojtkovski in \cite{BaWoEnGeo} for the dynamical entropy of the geodesic flow on a compact Riemannian manifold of nonpositive sectional curvature. Given such a Riemannian manifold $M,$ Ballmann and Wojtkovski proved that the dynamical
- Dynamic Electrophysical Characterization of Porous Silicon based Humidity Sensitive Elementscond-mat.mtrl-sci
S. Bravina, N. Morozovsky, R. Boukroub
The results of the investigation of changes of parameters of dynamic bipolar charge-voltage and bipolar and unipolar dynamic current-voltage characteristics and transient currents connected with the pulse change of humidity for the samples of por-Si are presented. The view of high voltage current-voltage curves is characteristic for poling processes in the s
William J. Henney
This review covers the dynamic processes that are important in the evolution and structure of galactic HII regions, concentrating on an elementary presentation of the physical concepts and recent numerical simulations of HII region evolution in a non-uniform medium. The contents are as follows: (1) The equations (Euler equations; Radiative transfer; Rate equ
R. E. Browne, D. Dudal, J. A. Gracey, V. E. R. Lemes
We review the current status of the application of the local composite operator technique to the condensation of dimension two operators in quantum chromodynamics (QCD). We pay particular attention to the renormalization group aspects of the formalism and the renormalization of QCD in various gauges.
The BABAR Collaboration, B. Aubert
We present updated results on time-dependent CP asymmetries in fully reconstructed B0->D(*)+-pi-+ and B0->D+-rho-+ decays in approximately 232 million Y(4S)->BBbar events collected with the BaBar detector at the PEP-II asymmetric-energy B factory at SLAC. From a time-dependent maximum likelihood fit we obtain for the parameters related to the CP violation an
P. G. Jonker, C. G. Bassa, G. Nelemans, A. M. Juett
In this Paper we report on our analysis of a ~25 ksec. Chandra X-ray observation of the neutron star soft X-ray transient (SXT) 1H1905+000 in quiescence. Furthermore, we discuss our findings of the analysis of optical photometric observations which we obtained using the Magellan telescope and photometric and spectroscopic observations which we obtained using
P. Kurlberg
If f is a polynomial with integer coefficients and q is an integer, we may regard f as a map from Z/qZ to Z/qZ. We show that the distribution of the (normalized) spacings between consecutive elements in the image of these maps becomes Poissonian as q tends to infinity along any sequence of square free integers such that the mean spacing modulo q tends to inf
Josefa Perez, Patricia B. Tissera, Diego G. Lambas, Cecilia Scannapieco
We carry out a statistical analysis of galaxy pairs selected from chemical hydrodynamical simulations with the aim at assessing the capability of hierarchical scenarios to reproduce recent observational results for galaxies in pairs. Particularly, we analyse the effects of mergers and interactions on the star formation (SF) activity, the global mean chemical
Vassilios Yannopapas
We study the blackbody spectrum from slabs of three-dimensional metallodielectric photonic crystals consisting of gold nanoparticles using an ab initio multiple-scattering method. The spectra are calculated for different photonic-crystal slab thicknesses, particle radii and hosting materials. We find in particular that such crystals exhibit a broadband emiss
N. Mauron, P. J. Huggins
We report the results of an exploratory program to image the extended circumstellar envelopes of asymptotic giant branch (AGB) stars in dust-scattered galactic light. The goal is to characterize the morphology of the envelopes as a probe of the mass-loss process. The observations consist of short exposures with the VLT and longer exposures with 1-2m telescop
Rudolf Baier, Paul Romatschke, Urs Achim Wiedemann
Recent discussions of RHIC data emphasized the exciting possibility that the matter produced in nucleus-nucleus collisions shows properties of a near-perfect fluid. Here, we aim at delineating the applicability of fluid dynamics, which is needed to quantify the size of corresponding dissipative effects. We start from the equations for dissipative fluid dynam
J. Arnlind, M. Bordemann, L. Hofer, J. Hoppe
We introduce C-Algebras (quantum analogues of compact Riemann surfaces), defined by polynomial relations in non-commutative variables and containing a real parameter that, when taken to zero, provides a classical non-linear, Poisson-bracket, obtainable from a single polynomial C(onstraint) function. For a continuous class of quartic constraints, we explicitl
Eef van Beveren
Within the independent-harmonic-oscillator model for quarks inside a hadron, a rigorous method is presented for the calculation of coupling constants and transition potentials for hadronic decay, as needed in a multi-channel description of mesons.
Eef van Beveren
Recoupling matrix elements are evaluated, in the harmonic oscillator approximation, for all possible angular and radial excitations in processes where quarks recombine. A diagrammatic representation is given. Their use is demonstrated in calculating the transition potential for rho to two pions in a pair creation model.
- Large n limit of Gaussian random matrices with external source, Part III: Double scaling limitmath-ph
Pavel M. Bleher, Arno B. J. Kuijlaars
We consider the double scaling limit in the random matrix ensemble with an external source $\frac{1}{Z_n} e^{-n \Tr({1/2}M^2 -AM)} dM$ defined on $n\times n$ Hermitian matrices, where $A$ is a diagonal matrix with two eigenvalues $\pm a$ of equal multiplicities. The value $a=1$ is critical since the eigenvalues of $M$ accumulate as $n \to \infty$ on two inte
Kedar Damle, T. Senthil
We study S=1 kagome antiferromagnets with isotropic Heisenberg exchange $J$ and strong easy axis single-ion anisotropy $D$. For $D \gg J$, the low-energy physics can be described by an effective $S=1/2$ $XXZ$ model with antiferromagnetic $J_z \sim J$ and ferromagnetic $J_\perp \sim J^2/D$. Exploiting this connection, we argue that non-trivial ordering into a
Umida Khodjaeva
The simple examples of spontaneous breaking of various symmetries for the scalar theory with fundamental mass have been considered. Higgs generalizations on "fundamental mass" were introduced into the theory on a basis of the five-dimensional de Sitter space.
- Field dependence of the magnetic spectrum in anisotropic and Dzyaloshinskii-Moriya antiferromagnets: II. Raman spectroscopycond-mat.str-el
L. Benfatto, M. B. Silva Neto, A. Gozar, B. S. Dennis
We compare the theoretical predictions of the previous article [L. Benfatto and M. B. Silva Neto, cond-mat/0602419], with Raman spectroscopy experiments in Sr(2)CuO(2)Cl(2) and untwinned La(2)CuO(4) single crystals. We construct the magnetic point group for the magnetically ordered phase of the two compounds, Sr(2)CuO(2)Cl(2) and La(2)CuO(4), and we classify
Carlos Pineda, Rudi Schaefer, Tomaz Prosen, Thomas H. Seligman
We study the time evolution of fidelity in a dynamical many body system, namely a kicked Ising model, modified to allow for a time reversal invariance breaking. We find good agreement with the random matrix predictions in the realm of strong perturbations. In particular for the time-reversal symmetry breaking case the predicted revival at Heisenberg time is
F. Castellano, R. C. Iotti, F. Rossi
We present modeling and simulation of prototypical multi bound state quantum well infrared photodetectors and show that such a detection design may overcome the problems arising when the operation frequency is pushed down into the far infrared spectral region. In particular, after a simplified analysis on a parabolic-potential design, we propose a fully thre
- Why pinning by surface irregularities can explain the peak effect in transport properties and neutron diffraction results in NbSe2 and Bi-2212 crystals?cond-mat.supr-con
Charles Simon, Alain Pautrat, Christophe Goupil, Joseph Scola
The existence of a peak effect in transport properties (a maximum of the critical current as function of magnetic field) is a well-known but still intriguing feature of type II superconductors such as NbSe2 and Bi-2212. Using a model of pinning by surface irregularities in anisotropic superconductors, we have developed a calculation of the critical current w
V. A. Khoze, A. D. Martin, M. G. Ryskin
We discuss the contribution of so-called semi-enhanced hard rescattering corrections to central exclusive diffractive Higgs production, pp -> p+H+p, at the LHC. We present arguments to show that these corrections are small. We confirm these expectations by considering HERA data for leading neutron production.
- Beyond Mean-Field Theory for Attractive Bosons under Transverse Harmonic Confinementcond-mat.stat-mech
Luca Salasnich
We study a dilute gas of attractive bosons confined in a harmonic cylinder, i.e. under cylindric confinement due to a transverse harmonic potential. We introduce a many-body wave function which extends the Bethe ansatz proposed by McGuire (J. Math. Phys. {\bf 5}, 622 (1964)) by including a variational transverse Gaussian shape. We investigate the ground stat
Katharina Vollmayr-Lee, Elizabeth A. Baker
We obtain evidence that the dynamics of glassy systems below the glass transition is characterized by self-organized criticality. Using molecular dynamics simulations of a model glass-former we identify clusters of cooperatively jumping particles. We find string-like clusters whose size is power-law distributed not only close to T_c but for ALL temperatures
Stein Olav Skrøvseth
We investigate the entanglement properties of a finite size 1+1 dimensional Ising spin chain, and show how these properties scale and can be utilized to reconstruct the ground state wave function. Even at the critical point, few terms in a Schmidt decomposition contribute to the exact ground state, and to physical properties such as the entropy. Nevertheless
V. B. Eltsov, A. P. Finne, R. Hanninen, J. Kopu
We study a twisted vortex bundle where quantized vortices form helices circling around the axis of the bundle in a "force-free" configuration. Such a state is created by injecting vortices into rotating vortex-free superfluid. Using continuum theory we determine the structure and the relaxation of the twisted state. This is confirmed by numerical calculation
R. M. Kiehn
This article examines how the physical presence of field energy and particulate matter could influence the topological properties of space time. The theory is developed in terms of vector and matrix equations of exterior differential forms. The topological features and the dynamics of such exterior differential systems are studied with respect to processes o
Li Liu, Yi Wang
This paper is devoted to the study of the log-convexity of combinatorial sequences. We show that the log-convexity is preserved under componentwise sum, under binomial convolution, and by the linear transformations given by the matrices of binomial coefficients and Stirling numbers of two kinds. We develop techniques for dealing with the log-convexity of seq
- Magnetic field dependence of the magnetic phase separation in Pr1-xCaxMnO3 manganites studied by small-angle neutron scatteringcond-mat.str-el
Damien Saurel, Annie Brulet, Andre Heinemann, Christine Martin
Transport properties of manganese oxides suggest that their colossal magnetoresistance (CMR) is due to percolation between ferromagnetic metallic (FM) clusters in an antiferromagnetic insulating (AFI) matrix. We have studied small-angle neutron scattering under applied magnetic field in CMR Pr1-xCaxMnO3 crystals for x around 0.33. Quantitative analysis of th
Maarten J Bergvelt
The usual vertex algebras have as underlying symmetry the Hopf algebra $H_D=\mathbb C[D]$ of infinitesimal translations. We show that it is possible to replace $H_D$ by another symmetry algebra $H_T=\mathbb C[T,T\inv]$, the group algebra of the Abelian group generated by $T$. $H_T$ is the algebra of symmetries of a lattice of rank 1, and the construction giv
Minoru Eto, Youichi Isozumi, Muneto Nitta, Keisuke Ohashi
A systematic method to obtain the effective Lagrangian on the BPS background in supersymmetric gauge theories is worked out, taking domain walls and vortices as concrete examples. The Lagrangian in terms of the superfields for four preserved SUSY is expanded in powers of the slow-movement parameter lambda. The expansion gives the superfield form of the BPS e
Nabin Kumar Jana
In this paper the Random Energy Model(REM) under exponential type environment is considered which includes double exponential and Gaussian cases. Limiting Free Energy is evaluated in these models. Limiting Gibbs' distribution is evaluated in the double exponential case.
- Enhanced Transmission of Light and Matter through Nanoapertures without Assistance of Surface Wavesphysics.optics
S. V. Kukhlevsky
Subwavelength aperture arrays in thin metal films enable enhanced transmission of light and matter waves [for example, see T.W. Ebbesen et al., Nature (London) 391, 667 (1998) and E. Moreno et al., Phys. Rev. Lett. 95, 170406 (2005)]. The phenomenon relies on resonant excitation of the surface electron or matter waves. We show another mechanism that provides