March 2009 arXiv papers — page 39
Showing 3,801–3,900 of 5,470 papers
Gleb Arutyunov, Marius de Leeuw, Alessandro Torrielli
We identify certain blocks in the S-matrix describing the scattering of bound states of the AdS5 x S5 superstring that allow for a representation in terms of universal R-matrices of Yangian doubles. For these cases, we use the formulas for Drinfeld's second realization of the Yangian in arbitrary bound-state representations to obtain the explicit express
Javiera Barrera, Olivier Bertoncini, Roberto Fernández
We link two phenomena concerning the asymptotical behavior of stochastic processes: (i) abrupt convergence or cut-off phenomenon, and (ii) the escape behavior usually associated to exit from metastability. The former is characterized by convergence at asymptotically deterministic times, while the convergence times for the latter are exponentially distributed
B. Pasquini, S. Boffi, A. V. Efremov, P. Schweitzer
The main properties of the leading-twist transverse momentum dependent parton distributions in a light-cone constituent quark model of the nucleon are reviewed, with focus on the role of the spin-spin and spin-orbit correlations of quarks. Results for azimuthal single spin asymmetries in semi-inclusive deep inelastic scattering are also discussed.
S. Aigrain, F. Pont, F. Fressin, A. Alapini
In this short paper, we study the photometric precision of stellar light curves obtained by the CoRoT satellite in its planet finding channel, with a particular emphasis on the timescales characteristic of planetary transits. Together with other articles in the same issue of this journal, it forms an attempt to provide the building blocks for a statistical i
Colin J. Lonsdale, Roger J. Cappallo, Miguel F. Morales, Frank H. Briggs
The Murchison Widefield Array (MWA) is a dipole-based aperture array synthesis telescope designed to operate in the 80-300 MHz frequency range. It is capable of a wide range of science investigations, but is initially focused on three key science projects. These are detection and characterization of 3-dimensional brightness temperature fluctuations in the 21
Theodoros E. Kouloukas, Vassilios G. Papageorgiou
A family of nonparametric Yang Baxter (YB) maps is constructed by refactorization of the product of two 2 by 2 matrix polynomials of first degree. These maps are Poisson with respect to the Sklyanin bracket. For each Casimir function a parametric Poisson YB map is generated by reduction on the corresponding level set. By considering a complete set of Casimir
Microscopic mechanism for experimentally observed anomalous elasticity of DNA in 2D
cond-mat.stat-mechNicolas Destainville, Manoel Manghi, John Palmeri
By exploring a recent model [Palmeri, J., M. Manghi, and N. Destainville. 2007. Phys. Rev. Lett. 99:088103] where DNA bending elasticity, described by the wormlike chain model, is coupled to base-pair denaturation, we demonstrate that small denaturation bubbles lead to anomalies in the flexibility of DNA at the nanometric scale, when confined in two dimensio
Non-thermal processes in colliding-wind massive binaries: the contribution of Simbol-X to a multiwavelength investigation
astro-ph.HEM. De Becker, R. Blomme, G. Micela, J. M. Pittard
Several colliding-wind massive binaries are known to be non-thermal emitters in the radio domain. This constitutes strong evidence for the fact that an efficient particle acceleration process is at work in these objects. The acceleration mechanism is most probably the Diffusive Shock Acceleration (DSA) process in the presence of strong hydrodynamic shocks du
Duration of interactions in quantum electrodynamics: basic concepts, temporal features of kinetic phenomena
quant-phMark E. Perel'man
For temporal magnitudes describing, in details, processes of particles scattering for a long time at each necessity case a particular, ad hoc reception were used. However the desirability of general approach basing on concepts of quantum field theory and uniting two main problems, durations of delay at scattering and of formation of arisen states, seems evid
Amos Lapidoth, Stefan M. Moser, Michele A. Wigger
New upper and lower bounds are presented on the capacity of the free-space optical intensity channel. This channel is characterized by inputs that are nonnegative (representing the transmitted optical intensity) and by outputs that are corrupted by additive white Gaussian noise (because in free space the disturbances arise from many independent sources). Due
James I. Lathrop, Jack H. Lutz, Scott M. Summers
Winfree (1998) showed that discrete Sierpinski triangles can self-assemble in the Tile Assembly Model. A striking molecular realization of this self-assembly, using DNA tiles a few nanometers long and verifying the results by atomic-force microscopy, was achieved by Rothemund, Papadakis, and Winfree (2004). Precisely speaking, the above self-assemblies tile
Leslie Greengard, Chris Stucchio
Reconstructing a finite set of curves from an unordered set of sample points is a well studied topic. There has been less effort that considers how much better the reconstruction can be if tangential information is given as well. We show that if curves are separated from each other by a distance D, then the sampling rate need only be O(sqrt(D)) for error-fre
Laszlo Erdos, Jan Philip Solovej
We consider a large atom with nuclear charge $Z$ described by non-relativistic quantum mechanics with classical or quantized electromagnetic field. We prove that the absolute ground state energy, allowing for minimizing over all possible self-generated electromagnetic fields, is given by the non-magnetic Thomas-Fermi theory to leading order in the simultaneo
Kengo Tachihara, Ralph Neuhaeuser, Yasuo Fukui
We report on a search for the parental molecular clouds of the TW Hya association (TWA), using CO emission and Na I absorption lines. TWA is the nearest young (~ 50 pc; ~ 10 Myr) stellar association, yet in spite of its youth, there are no detection of any associated natal molecular gas, as is the case for other typical young clusters. Using infrared maps as
Motoi Endo, Tetsuo Shindou
A decay of the gravitino dark matter is an attractive candidate to explain the current excesses of the PAMELA/ATIC cosmic-ray data. However, R-parity violations are required to be very tiny in low-energy scale. We suggest a R-parity violation in the right-handed neutrino sector. The violation is suppressed by a see-saw mechanism. Although a reheating tempera
Jean-Michel Caillol
We consider the exact renormalization group for a non-canonical scalar field theory in which the field is coupled to the external source in a special non linear way. The Wilsonian action and the average effective action are then simply related by a Legendre transformation up to a trivial quadratic form. An exact mapping between canonical and non-canonical th
Collapse and Fragmentation of Molecular Cloud Cores. X. Magnetic Braking of Prolate and Oblate Cores
astro-ph.GAAlan P. Boss
The collapse and fragmentation of initially prolate and oblate, magnetic molecular clouds is calculated in three dimensions with a gravitational, radiative hydrodynamics code. The code includes magnetic field effects in an approximate manner: magnetic pressure, tension, braking, and ambipolar diffusion are all modelled. The parameters varied for both the ini
Peter Nägele, Ulrich Weiss
We study the dynamics of dissipative spins for general spin-spin coupling. We investigate the population dynamics and relaxation of the purity in the white noise regime, in which exact results are available. Inter alia, we find distinct reduction of decoherence and slowdown of purity decay around degeneracy points. We also determine in analytic form the one-
M. Debessai, T. Matsuoka, J. J. Hamlin, J. S. Schilling
Divalent Eu (4f7, J=7/2) possesses a strong local magnetic moment which suppresses superconductivity. Under sufficient pressure it is anticipated that Eu will become trivalent (4f6, J=0) and a weak Van Vleck paramagnet, thus opening the door for a possible superconducting state, in analogy with Am metal (5f6, J=0) which superconducts at 0.79 K. We present ac
M. M. Maslov, D. A. Lobanov, A. I. Podlivaev, L. A. Openov
The reasons for the anomalously high thermal stability of cubane C8H8 and the mechanisms of its decomposition are studied by numerically simulating the dynamics of this metastable cluster at T = 1050 - 2000 K using a tight-binding potential. The decomposition activation energy is found from the temperature dependence of the cubane lifetime obtained from the
X. Du, Y. Zhang, J. E. Thomas
We report the measurement of inelastic three-body and two-body collisional decay rates for a two-component Fermi gas of $^6$Li, which are highly suppressed by the Pauli exclusion principle. Our measurements are made in the BEC-BCS crossover regime, near the two-body collisional (Feshbach) resonance. At high temperature (energy) the data shows a dominant thre
Comparing Correlation Lengths of Red and Blue Galaxies: A New Standard Length for Testing Cosmic Isotropy
astro-ph.COMichael J. Longo
I introduce a simple empirical measure of average galaxy cluster sizes based on a comparison of the correlation lengths of red galaxies with blue that can provide a more accurate and bias-free measure of the average size and number density of galaxy clusters. Using 269,000 galaxies from the SDSS DR6 survey, I show that this 3D correlation length, averaged ov
Macroscopic Superpositions, Decoherent Histories and the Emergence of Hydrodynamic Behaviour
quant-phJ. J. Halliwell
Macroscopic systems are described most completely by local densities (particle number, momentum and energy) yet the superposition states of such physical variables, indicated by the Everett interpretation, are not observed. In order to explain this, it is argued that histories of local number, momentum and energy density are approximately decoherent when coa
Aruna Kumar Nayak
The cross section for production of Z bosons with two associated b-jets, and Z decaying to leptons, can be measured at the LHC with about 100 pb-1 of data. We use simulated data to study possible strategies for an early measurement of this process with the CMS detector. The rate and kinematic properties of this final state needs to be well understood because
A. Mikovic
In this essay we describe a platonic metaphysics where time is a fundamental idea such that the passage of time is independent of observers and the laws of physics. Furthermore, time serves to distinguish between a real and an abstract universe, where a real universe is an appropriatelly ordered set of ideas in time, while an abstract universe is such a set
J. J. Halliwell
Any account of the emergence of classicality from quantum theory must address the fact that the quantum operators representing positions and momenta do not commute, whereas their classical counterparts suffer no such restrictions. To address this, we revive an old idea of von Neumann, and seek a pair of commuting operators $X,P$ which are, in a specific sens
A. Schuh, A. Fritsch, J. Q. Ginepro, M. Heim
Thirty-six gold isotopes have so far been observed; the discovery of these isotopes is discussed. For each isotope a brief summary of the first refereed publication, including the production and identification method, is presented.
A Parameter-Uniform Finite Difference Method for Multiscale Singularly Perturbed Linear Dynamical Systems
math.NAS Valarmathi, John J H Miller
A system of singularly perturbed ordinary differential equations of first order with given initial conditions is considered. The leading term of each equation is multiplied by a small positive parameter. These parameters are assumed to be distinct and they determine the different scales in the solution to this problem. A Shishkin piecewise--uniform mesh is c
Alexander L. Kagan, Gilad Perez, Tomer Volansky, Jure Zupan
A model independent study of the minimal flavor violation (MFV) framework is presented, where the only sources of flavor breaking at low energy are the up and down Yukawa matrices. Two limits are identified for the Yukawa coupling expansion: linear MFV, where it is truncated at the leading terms, and nonlinear MFV, where such a truncation is not possible due
Yvon Maday, Julien Salomon
The control of quantum phenomena is a topic that has carried out many challenging problems. Among others, the Hamiltonian identification, i.e, the inverse problem associated with the unknown features of a quantum system is still an open issue. In this work, we present an algorithm that enables to design a set of selective laser fields that can be used, in a
X. Artru, C. Ray
The electromagnetic wave field propagating in a helical wave guide is decomposed in an angular momentum basis. Eigenmodes are calculated using a truncation in $l$ and a discretisation of the boundary condition. Modes slightly slower than light are considered for relativistic particle acceleration.
Constraint algorithm for k-presymplectic Hamiltonian systems. Application to singular field theories
math-phXavier Gracia, Ruben Martin, Narciso Roman-Roy
The k-symplectic formulation of field theories is especially simple, since only tangent and cotangent bundles are needed in its description. Its defining elements show a close relationship with those in the symplectic formulation of mechanics. It will be shown that this relationship also stands in the presymplectic case. In a natural way, one can mimick the
Dirk Bollen, Harry Halpin
Most tagging systems support the user in the tag selection process by providing tag suggestions, or recommendations, based on a popularity measurement of tags other users provided when tagging the same resource. In this paper we investigate the influence of tag suggestions on the emergence of power law distributions as a result of collaborative tag behavior.
S. Ivashkovich
In the works of Darboux and Walsh it was remarked that a one to one self mapping of $\rr^3$ which sends convex sets to convex ones is affine. It can be remarked also that a $\calc^2$-diffeomorphism $F:U\to U^{'}$ between two domains in $\cc^n$, $n\ge 2$, which sends pseudoconvex hypersurfaces to pseudoconvex ones is either holomorphic or antiholomorphic.
Thomas Olsen
We calculate the inelastic scattering probabilities in the wide band limit of a local polaron model with quadratic coupling to bosons. The central object is a two-particle Green function which is calculated exactly using a purely algebraic approach. Compared with the usual linear interaction term a quadratic interaction term gives higher probabilities for in
Xavier Mary
We study generalized inverses on semigroups by means of Green's relations. We first define the notion of inverse along an element and study its properties. Then we show that the classical generalized inverses (group inverse, Drazin inverse and Moore-Penrose inverse) belong to this class.
Compactness estimates for the $\overline \partial $ - Neumann problem in weighted $L^2$ - spaces
math.CVKlaus Gansberger, Friedrich Haslinger
In this paper we discuss compactness estimates for the $\bar \partial $-Neumann problem in the setting of weighted $L^2$-spaces on $\mathbb{C}^n.$ For this purpose we use a version of the Rellich - Lemma for weighted Sobolev spaces.
Timothy A. Davis, Peter J. Wheatley
We investigate the evaporation history of known transiting exoplanets in order to consider the origin of observed correlations between mass, surface gravity and orbital period. We show that the survival of the known planets at their current separations is consistent with a simple model of evaporation, but that many of the same planets would not have survived
Kim Ruane
We specify exactly which groups can act geometrically on CAT(0) spaces whose visual boundary is homeomorphic to either a circle or a suspension of a Cantor set.
P. Rudra
We have summarized here the astronomical knowledge of the ancient Hindu astronomers. This knowledge was accumulated from before 1500 B.C. up to around 1200 A.D. In Section \ref{equiv} we have correlated terms used by the Hindu astronomers and their equivalents in modern astronomy. In Section \ref{coord} we have defined the different astronomical coordinate s
Mechanism of Canted Magnetic Structure Formation in the Absence of Spin-Orbital Interaction
cond-mat.otherE. V. Rosenfeld
A simple exactly solvable model of canted magnetic structure appearance in the system of crystallographic and chemically equivalent atoms is proposed. The corresponding mechanism originates from the competition of intra- and interatomic exchange interactions.
Ping Liao, Qin-Qin Wu, Jie-Qiao Liao, Le-Man Kuang
We study decoherence in a circuit QED system consisting of a charge qubit and two superconducting transmission line resonators (TLRs). We show that in the dispersive regime of the circuit QED system one TLR can be used as an auxiliary subsystem to realize decoherence-free quantum dynamics of the bipartite target system consisting of the charge qubit and the
The ALADIN2000 Collaboration, C. Sfienti, P. Adrich, T. Aumann
The A/Z dependence of projectile fragmentation at relativistic energies has been studied with the ALADIN forward spectrometer at SIS. A stable beam of 124Sn and radioactive beams of 124La and 107Sn at 600 MeV per nucleon have been used in order to explore a wide range of isotopic compositions. Chemical freeze-out temperatures are found to be nearly invariant
Utkir A. Rozikov, Jianjun Paul Tian
In this article we study algebraic structures of function spaces defined by graphs and state spaces equipped with Gibbs measures by associating evolution algebras. We give a constructive description of associating evolution algebras to the function spaces (cell spaces) defined by graphs and state spaces and Gibbs measure $μ$. For finite graphs we find some e
Wigner operator's new transformation in phase space quantum mechanics and its applications
quant-phHong-yi Fan
Using operators' Weyl ordering expansion formula (Hong-yi Fan,\emph{\}J. Phys. A 25 (1992) 3443) we find new two-fold integration transformation about the Wigner operator $Δ(q',p')$ ($q$-number transform) in phase space quantum mechanics, \[ \iint_{-\infty}^\infty dp' dq'/πΔ(q',p') e^{-2i(p-p') (q-q')} =δ(p-P) δ(q-Q), \] a
F. Lignieres, B. Georgeot
The asteroseismology of rapidly rotating pulsating stars is hindered by our poor knowledge of the effect of the rotation on the oscillation properties. Here we present an asymptotic analysis of high-frequency acoustic modes in rapidly rotating stars. We study the Hamiltonian dynamics of acoustic rays in uniformly rotating polytropic stars and show that the p
P. Antolin, K. Shibata, T. Kudoh, D. Shiota
Alfven waves created by sub-photospheric motions or by magnetic reconnection in the low solar atmosphere seem good candidates for coronal heating. However, the corona is also likely to be heated more directly by magnetic reconnection, with dissipation taking place in current sheets. Distinguishing observationally between these two heating mechanisms is an ex
Jochen Bröcker
An important tool to quantify the likeness of two probability measures are f-divergences, which have seen widespread application in statistics and information theory. An example is the total variation, which plays an exceptional role among the f-divergences. It is shown that every f-divergence is bounded from below by a monotonous function of the total varia
V. Sguera, G. E. Romero, A. Bazzano, N. Masetti
3EG J1837-0423 and HESS J1841-055 are two unidentified and peculiar high-energy sources located in the same region of the sky, separated by 1.4 deg. Specifically, 3EG J1837-0423 is a transient MeV object detected by EGRET only once during flaring activity that lasted a few days while HESS J1841-055 is a highly extended TeV source. We attempted to match the h
Robert D. Grober
It is shown that the putting stroke of world class golfers can be described as the motion of a pendulum driven at twice its natural resonance frequency. This model minimizes error in the speed of the putter head due to random errors in the magnitude of the applied forces, providing rational for why great players have developed this particular putting stroke.
P. Klaja, R. Czyzykiewicz, P. Moskal
We present a comparison of the two-body invariant mass distributions for the pp -> ppeta and pp -> ppeta-prime reactions, both measured at a nominal excess energy value of Q = 15.5 MeV. For the pp -> ppeta reaction, in addition, the differential cross sections were extracted for an excess energy of Q = 10 MeV. The comparison of the results for the eta and et
M. T. Dova, M. E. Manceñido, A. G. Mariazzi, H. Wahlberg
Azimuthal asymmetries in signals of non vertical showers have been observed in ground arrays of water Cherenkov detectors, like Haverah Park and the Pierre Auger Observatory. The asymmetry in time distributions of arriving particles offers a new possibility for the determination of the mass composition. The dependence of this asymmetry on atmospheric depth s
J. S. Clark, I. Negueruela, B. Davies, V. M. Larionov
We aim to characterise the properties of a third massive, red supergiant dominated galactic cluster. To accomplish this we utilised a combination of near/mid-IR photometry and spectroscopy to identify and classify the properties of cluster members, and statistical arguments to determine the mass of the cluster. We found a total of 16 strong candidates for cl
Stanislav Shkarin
We prove that any bounded linear operator on $L_p[0,1]$ for $1\leq p<\infty$, commuting with the Volterra operator $V$, is not weakly supercyclic, which answers affirmatively a question raised by Léon-Saavedra and Piqueras-Lerena. It is achieved by providing an algebraic flavored condition on an operator which prevents it from being weakly supercyclic and is
V. Hambaryan, R. Neuhäuser, F. Haberl, M. M. Hohle
We found a narrow absorption feature at 0.57keV in the co-added RGS spectrum of the isolated neutron star RX J0720.4-3125 with an equivalent width of 1.35+/-0.3eV and FWHM ~6.0eV. The feature was identified with an absorption line of highly ionized oxygen OVII, most probably originating in the ambient medium of RX J0720.4-3125. An extensive investigation wit
Maureen Lagos, Fernando Sato, Jeferson Bettini, Varlei Rodrigues
Understanding the mechanical properties of nanoscale systems requires a range of measurement techniques and theoretical approaches to gather the relevant physical and chemical information. The arrangements of atoms in nanostructures and macroscopic matter can be different, principally due to the role of surface energy, but the interplay between atomic and el
Shabnam Akhtari
As an application of the method of Thue-Siegel, we will resolve a conjecture of Walsh to the effect that the Diophantine equation $aX^{4} - bY^2=1$, for fixed positive integers $a$ and $b$, possesses at most two solutions in positive integers $X$ and $Y$. Since there are infinitely many pairs $(a,b)$ for which two such solutions exist, this result is sharp.
M. Frank, V. Manuilov, E. Troitsky
Continuous actions of topological groups on compact Hausdorff spaces $X$ are investigated which induce almost periodic functions in the corresponding commutative C*-algebra. The unique invariant mean on the group resulting from averaging allows to derive a C*-valued inner product and a Hilbert C*-module which serve as an environment to describe characteristi
Hamza Chraibi, Didier Lasseux, Eric Arquis, Régis Wunenburger
We study numerically the deformation of sessile dielectric drops immersed in a second fluid when submitted to the optical radiation pressure of a continuous Gaussian laser wave. Both drop stretching and drop squeezing are investigated at steady state where capillary effects balance the optical radiation pressure. A boundary integral method is implemented to
Jean-Pierre Delville, Matthieu Robert De Saint-Vincent, Robert D. Schroll, Hamza Chraibi
The development of microfluidic devices is still hindered by the lack of robust fundamental building blocks that constitute any fluidic system. An attractive approach is optical actuation because light field interaction is contactless and dynamically reconfigurable, and solutions have been anticipated through the use of optical forces to manipulate micropart
Hamza Chraibi, M. Prat, O. Chapuis
We study numerically the influence of contact angle on slow evaporation in two-dimensional model porous media. For sufficiently low contact angles, the drying pattern is fractal and can be predicted by a simple model combining the invasion percolation model with the computation of the diffusive transport in the gas phase. The overall drying time is minimum i
Global controllability and stabilization for the nonlinear Schrödinger equation on some compact manifolds of dimension 3
math.APCamille Laurent
We prove global internal controllability in large time for the nonlinear Schrödinger equation on some compact manifolds of dimension 3. The result is proved under some geometrical assumptions : geometric control and unique continuation. We give some examples where they are fulfilled on $\Tot$, $S^3$ and $S^2\times S^1$. We prove this by two different methods
Francisco Torralbo, Francisco Urbano
Compact flat surfaces of homogeneous Riemannian 3-manifolds with isometry group of dimension 4 are classified. Non-existence results for compact constant Gauss curvature surfaces in these 3-manifolds are established.
Cobordism of Morse functions on surfaces, the universal complex of singular fibers and their application to map germs
math.GTOsamu Saeki
We give a new and simple proof for the computation of the oriented and the unoriented fold cobordism groups of Morse functions on surfaces. We also compute similar cobordism groups of Morse functions based on simple stable maps of 3-manifolds into the plane. Furthermore, we show that certain cohomology classes associated with the universal complexes of singu
Vladan Pankovic, Aleksandar-Meda Radakovic
In this work we present a close correlation between third Kepler law and Titius-Bode empirical rule. Concretely, we demonstrate that third Kepler law, or, corresponding equilibrium condition between centrifugal and Newtonian gravitational force, implies that planet orbital momentum becomes effectively a function of the planet distance as unique variable and
The XMM Cluster Survey: Galaxy Morphologies and the Color-Magnitude Relation in XMMXCS J2215.9-1738 at z=1.46
astro-ph.COMatt Hilton, S. Adam Stanford, John P. Stott, Chris A. Collins
We present a study of the morphological fractions and color-magnitude relation in the most distant X-ray selected galaxy cluster currently known, XMMXCS J2215.9-1738 at z=1.46, using a combination of optical imaging data obtained with the Hubble Space Telescope Advanced Camera for Surveys, and infrared data from the Multi-Object Infrared Camera and Spectrogr
Vladan Pankovic, Rade Glavatovic, Marko Mandic, Vojislav Bozic-Sremac
In this work we do an "interpolation" of Scardigli theory of a quantum-like description of the planetary system that reproduces remarkable Titius-Bode-Richardson rule. More precisely, instead of simple, approximate, Bohr-like theory, or, accurate, Schr$\ddot{o}$dinger-like theory, considered by Scardigli, we suggest originally a semi-accurate, de Bro
Magnetic properties of nanosized diluted magnetic semiconductors with band splitting
cond-mat.mtrl-sciE. Z. Meilikhov, R. M. Farzetdinova
The continual model of the nonuniform magnetism in thin films and wires of a diluted magnetic semiconductor is considered with taking into account the finite spin polarization of carriers responsible for the indirect interaction of magnetic impurities (e.g. via RKKY mechanism). Spatial distributions (across the film thickness or the wire radius) of the magne
E. Z. Meilikhov, R. M. Farzetdinova
Magnetic properties of the planar structure consisting of a ferromagnetic metal and the diluted magnetic semiconductor are considered (by the example of the structure Fe/Ga(Mn)As, experimentally studied in [F. Maccherozzi, e.a., Phys. Rev. Lett., 101, 267201 (2008)]). In the framework of the mean field theory, we demonstrate the presence of the significant a
Yang Chen, Mourad E. H. Ismail
The "Diophantine" property of the zeros of certain polynomials in the Askey scheme, recently discovered by Calogero and his collaborators, is explained, with suitably chosen parameter values, in terms of the summation theorem of hypergeometric series. Here the Diophantine property refers to integer valued zeros. It turns out that the same procedure c
V. Spokoiny
The paper offers a novel unified approach to studying the accuracy of parameter estimation by the quasi likelihood method. Important features of the approach are: (1) The underlying model {is not assumed to be parametric}. (2) No conditions on parameter identifiability are required. The parameter set can be unbounded. (3) The model assumptions are quite gene
G. Lesur, J. C. B. Papaloizou
(Abriged) The existence of large-scale and long-lived 2D vortices in accretion discs has been debated for more than a decade. They appear spontaneously in several 2D disc simulations and they are known to accelerate planetesimal formation through a dust trapping process. However, the issue of the stability of these structures to the imposition of 3D disturba
C Bernicot
All one-massless-loop Feynman diagrams could be written like a linear combination of scalar boxes, triangles an bubbles in $n$ dimensions plus rational terms. However, the four-point scalar integrals in $n+2$ dimensions are free of infrared divergences. We are going to change the dimensions of the scalar boxes $n \to n+2$ and the using of this degree of free
G. Letawe, P. Magain, V. Chantry, Y. Letawe
The QSO HE0450-2958 was brought to the front scene by the non-detection of its host galaxy and strong upper limits on the latter's luminosity. The QSO is also a powerful infrared emitter, in gravitational interaction with a strongly distorted UltraLuminous InfraRed companion galaxy. We investigate the properties of the companion galaxy, through new near-
Jarmo Hietarinta, Da-jun Zhang
In Part I [arXiv:0902.4873 [nlin.SI]] soliton solutions to the ABS list of multi-dimensionally consistent difference equations (except Q4) were derived using connection between the Q3 equation and the NQC equations, and then by reductions. In that work central role was played by a Cauchy matrix. In this work we use a different approach, we derive the $N$-sol
Improved Lower Bounds on Capacities of Symmetric 2-Dimensional Constraints using Rayleigh Quotients
cs.ITErez Louidor, Brian Marcus
A method for computing lower bounds on capacities of 2-dimensional constraints having a symmetric presentation in either the horizontal or the vertical direction is presented. The method is a generalization of the method of Calkin and Wilf (SIAM J. Discrete Math., 1998). Previous best lower bounds on capacities of certain constraints are improved using the m
N. Honda, G. Morando
In this paper we introduce the sheaf of stratified Whitney jets of Gevrey order on the subanalytic site relative to a real analytic manifold X. Then we define stratified ultradistributions of Beurling and Roumieu type on X. In the end, by means of stratified ultradistributions, we define tempered-stratified ultradistributions and we prove two results. First,
Fermi/LAT discovery of gamma-ray emission from the flat-spectrum radio quasar PKS 1454-354
astro-ph.HELAT Collaboration, A. A. Abdo, P. G. Edwards, M. M. Chester
We report the discovery by the Large Area Telescope (LAT) onboard the Fermi Gamma-ray Space Telescope of high-energy gamma-ray (GeV) emission from the flat-spectrum radio quasar PKS 1454-354 (z=1.424). On 4 September 2008 the source rose to a peak flux of (3.5 +/- 0.7)x 10^-6 ph cm^-2 s^-1 (E > 100 MeV) on a time scale of hours and then slowly dropped over t
Variable polarization measured in the prompt emission of GRB 041219A using IBIS on board INTEGRAL
astro-ph.HED. Gotz, P. Laurent, F. Lebrun, F. Daigne
Polarization measurements provide direct insight into the nature of astrophysical processes. Unfortunately, only a few instruments are available for this kind of measurements at gamma-ray energies, and the sources need to be very bright. Gamma-Ray Bursts (GRBs) are ideal candidates due to their large flux over limited time intervals, maximizing the available
A. Baldi, M. Gonzalez-Silveira, V. Palmisano, B. Dam
We tune the thermodynamics of hydrogen absorption in Mg by means of elastic clamping. The loading isotherms measured by hydrogenography show that Mg films covered with Mg-alloy-forming elements, such as Pd and Ni, have hydrogen plateau pressures more than two orders of magnitude higher than bulk Mg at the same temperature. An elastic model allows us to inter
M. M. Ettefaghi
We extend the noncommutative (NC) standard model to incorporate singlet particles as cold dark matter. In the NC space-time, the singlet particles can be coupled to the U(1) gauge field in the adjoint representation. We Study the relic density of the singlet particles due to the NC induced interaction. Demanding either the singlet fermion or the singlet scal
Metallicity effects in the spectral classification of O-type stars. Theoretical consideration
astro-ph.CON. Markova, L. Bianchi, B. Efremova, J. Puls
Based on an exteded grid of NLTE, line blanketed model atmospheres with stellar winds as calculated by means of FASTWIND, we have investigated the change in the strengths of strategic Helium transitions in the optical as caused by a 0.3 decrease in metallicity with respect to solar abundances. Our calculations predict that only part of the observed increase
Bertrand J. Guillou
We describe a construction of an object associated to the fundamental group of the projective line minus three points in the Bloch-Kriz category of mixed Tate motives. This description involves Massey products of Steinberg symbols in the motivic cohomology of the ground field.
Pierre-Olivier Mattei
It was recently observed in a numerical study on a high order perturbation method under heavy fluid loading that a loaded vibrating plate results, not only in the classical frequency shift of the in vacuo single resonance (in both the real part because of the fluid added mass and the imaginary part because of energy lost by radiation), but also in an increas
Natalia Castellana, Juan A. Crespo, Jerome Scherer
The class of loop spaces whose mod p cohomology is Noetherian is much larger than the class of p-compact groups (for which the mod p cohomology is required to be finite). It contains Eilenberg-Mac Lane spaces such as the infinite complex projective space and 3-connected covers of compact Lie groups. We study the cohomology of the classifying space BX of such
Endogenous circannual rhythm in LH secretion: insight from signal analysis coupled with mathematical modelling
math.DSAlexandre Vidal, Claire Médigue, Benoit Malpaux, Frédérique Clément
In sheep as in many vertebrates, the seasonal pattern of reproduction is timed by the annual photoperiodic cycle, characterized by seasonal changes in the daylength. The photoperiodic information is translated into a circadian profile of melatonin secretion. After multiple neuronal relays (within the hypothalamus), melatonin impacts GnRH (gonadotrophin relea
David Bachman
We construct families of pairs of Heegaard splittings that must be stabilized several times to become equivalent. The first such pair differs only by their orientation. These are genus n splittings of a closed 3-manifold that must be stabilized at least n-2 times to become equivalent. The second is a pair of genus n splittings of a manifold with toroidal bou
Yan-Yang Zhang, Chen Fang, Xiaoting Zhou, Kangjun Seo
Using both two orbital and five orbital models, we investigate the quasiparticle interference (QPI) patterns in the superconducting (SC) state of iron-based superconductors. We compare the results for nonmagnetic and magnetic impurities in sign-changed s-wave $\cos(k_x)\cdot\cos(k_y)$ and sign-unchanged $|\cos(k_x)\cdot\cos(k_y)|$ SC states. While the patter
Direct Observation of Photonic Jets and Corresponding Backscattering Enhancement at Microwave frequencies
physics.opticsLi Zhao, C. K. Ong
We experimentally verified the phenomena of photonic jets generated by plane-electromagnetic-wave-illuminated dielectric micro-cylinders with diameter comparable to the corresponding wavelength at microwave frequencies. Using a home-made 2D spatial field mapping system, we carried out a point-by-point measurement of both phase and intensity of spatial electr
David Bachman
In earlier work we introduced topologically minimal surfaces as the analogue of geometrically minimal surfaces. Here we strengthen the analogy by showing that complicated amalgamations act as barriers to low genus, topologically minimal surfaces.
Reproducibility of room temperature ferromagnetism in Zn0.95Mn0.05O and its understanding
cond-mat.str-elR. N. Bhowmik, Asok Poddar, A. Saravanan
The present work reproduces the room temperature ferromagnetism by doping magnetic Mn atoms in diamagnetic ZnO. The ferromagnetic ordering is extended up to 640 K in mechanical milled Zn0.95Mn0.05O samples. The bulk and nanocrystalline samples are stabilized in hexagonal crystal structure with space group p63mc. The grain size and lattice strain of the sampl
Mikami Hirasawa, Kunio Murasugi
Suppose the knot group G(K) of a knot K has a non-abelian representation ρon A_4 \subset GL(4,Z). We conjecture that the twisted Alexander polynomial of K associated to ρis of the form: Δ_K(t)/(1-t) ϕ(t^3), where Δ_K (t) is the Alexander polynomial of K and ϕ(t^3) is an integer polynomial in t^3. We prove the conjecture for 2-bridge knots K whose group G(K)
K. Shiokawa
Certain quantum topological invariants of three manifolds can be written in the form of the Gaussian sum. It is shown that such topological invariants can be approximated efficiently by a quantum computer. The invariants discussed here are obtained as a partition function of the gauge theory on three manifolds with various gauge groups. Our algorithms are ap
Size of Orbital Ordering Domain Controlled by the Itinerancy of the 3d Electrons in a Manganite Thin Film
cond-mat.str-elY. Wakabayashi, H. Sagayama, T. Arima, M. Nakamura
An electronic effect on a macroscopic domain structure is found in a strongly correlated half-doped manganite film Nd$_{0.5}$Sr$_{0.5}$MnO3 grown on a (011) surface of SrTiO3. The sample has a high-temperature (HT) phase free from distortion above 180K and two low-temperature (LT) phases with a large shear-mode strain and a concomitant twin structure. One LT
Taichi Kato, Elena P. Pavlenko, Hiroyuki Maehara, Kazuhiro Nakajima
We observed the 2006 superoutburst of SDSS J080434.20+510349.2 during its plateau phase, rebrightening phase, and post-superoutburst final decline. We found that this object is a grazing eclipsing system with a period of 0.0590048(2) d. Well-defined eclipses were only observed during the late stage of the superoutburst plateau and the depth decreased during
First model-independent determination of the relative strong phase between D0 and D0B --> K0Spi+pi- and its impact on the CKM Angle gamma/phi3 measurement
hep-exThe CLEO Collaboration, R. A. Briere
We exploit the quantum coherence between pair-produced D0 and D0B in psi(3770) decays to make a first determination of the relative strong phase differences between D0--> K0Spi+pi- and D0B--> K0Spi+pi-, which are of great importance in determining the CKM angle gamma/phi3 in B- --> D0 (D0B) K- decays. Using 818 1/pb of e+e- collision data collected with the
Transition frequency shifts with fine-structure constant variation for Fe I. Isotope shift calculations in Fe I and Fe II
astro-ph.COS. G. Porsev, M. G. Kozlov, D. Reimers
In this paper we calculated the relativistic corrections to transition frequencies (q factors) of Fe I for the transitions from the even- and odd-parity states to the ground state. We also carried out isotope shift calculations in Fe I and Fe II. To the best of our knowledge, the isotope shift in Fe I was calculated for the first time.
On the X-ray emission from massive star clusters and their evolving superbubbles II. Detailed analytics and observational effects
astro-ph.COG. A. Añorve-Zeferino, G. Tenorio-Tagle, S. Silich
In this work, we present a comprehensive X-ray picture of the interaction between a super star cluster and the ISM. In order to do that, we compare and combine the X-ray emission from the superwind driven by the cluster with the emission from the wind-blown bubble. Detailed analytical models for the hydrodynamics and X-ray luminosity of fast polytropic super
Feng Qi, Bai-Ni Guo
In this note, we present monotonicity results of a function involving to the inverse hyperbolic sine. From these, we derive some inequalities for bounding the inverse hyperbolic sine.
A Simple Cooperative Transmission Protocol for Energy-Efficient Broadcasting Over Multi-Hop Wireless Networks
cs.NIAravind Kailas, Lakshmi Thanayankizil, Mary Ann Ingram
This paper analyzes a broadcasting technique for wireless multi-hop sensor networks that uses a form of cooperative diversity called opportunistic large arrays (OLAs). We propose a method for autonomous scheduling of the nodes, which limits the nodes that relay and saves as much as 32% of the transmit energy compared to other broadcast approaches, without re