August 2005 arXiv papers — page 10
Showing 901–1,000 of 3,714 papers
Magda Arnaboldi
I will review the latest results for the presence of diffuse light in the nearby universe and at intermediate redshift, and then discuss the latest results from hydrodynamical cosmological simulations of cluster formation on the expected properties of diffuse light in clusters. I shall present how intracluster planetary nebulae (ICPNe) can be used as excelle
The "K-Correction" for Irradiated Emission Lines in LMXBs: Evidence for a Massive Neutron Star in X1822-371 (V691 CrA)
astro-phT. Muñoz-Darias, J. Casares, I. G. Martínez-Pais
We study the K-correction for the case of emission lines formed in the X-ray illuminated atmosphere of a Roche lobe filling star. We compute the K-correction as function of the mass ratio 'q' and the disc flaring angle 'alpha' using a compact binary code where the companion's Roche lobe is divided into 10^5 resolution elements. We also st
T. J. -L. Courvoisier, M. Turler
We discuss accretion flows on massive black holes in which different elements of the flow (clumps) have velocities that may differ substantially. We estimate the consequence of collisions between these clumps as they come close to the central object and calculate the resulting radiation. We show that this radiation is similar to that observed in the optical
Francesco Palla
Young stars on their way to the ZAMS evolve in significantly different ways depending on mass. While the theoretical and observational properties of low- and intermediate-mass stars are rather well understood and/or empirically tested, the situation for massive stars (>10-15 Msun) is, to say the least, still elusive. On theoretical grounds, the PMS evolution
Observation of VHE gamma-ray emission from the Active Galactic Nucleus 1ES1959+650 using the MAGIC telecope
astro-phJ. Albert et al.
The MAGIC Cherenkov telescope has observed very high energy (VHE) gamma-ray emission from the Active Galactic Nucleus 1ES1959+650 during six hours in September and October 2004. The observations were carried out alternated with the Crab Nebula, whose data were used as reference source for optimizing gamma/hadron separation and for flux comparison. The data a
Constraints on radiatively inefficient accretion history of active galactic nuclei from hard cosmological X-ray background
astro-phXinwu Cao
The transition of a standard thin disk to a radiatively inefficient accretion flow (RIAF) is expected to occur, when its dimensionless accretion rate is lower than the critical value. The RIAF is very hot, and it radiates mostly in the hard X-ray band (>100 keV). Assuming that the accretion disk in every bright active galactic nucleus (AGN) will finally unde
Masses of high-z galaxy hosting haloes from angular clustering and their evolution in the CDM model
astro-phTakashi Hamana, Toru Yamada, Masami Ouchi, Ikuru Iwata
We examine masses of hosting haloes of two photometrically-selected high-z galaxy samples: the old passively-evolving galaxies (OPEGs) and Lyman Break Galaxies (LBGs) both taken from the Subaru/XMM-Newton Deep Survey (SXDS). The large survey area of the SXDS (1sq deg) allows us to measure the angular two-point correlation functions to a wide separation of >1
A. A. Schekochihin, S. C. Cowley
We propose a model of magnetic-field growth in galaxy clusters whereby the field is amplified by a factor of about 10^8 over a cosmologically short time of ~10^8 yr. Our model is based on the idea that the viscosity of the intracluster medium during the field-amplification epoch is determined not by particle collisions but by plasma microinstabilities: these
A New Apsidal Motion Determination of the Eclipsing Binary Star V459 Cassiopeiae: A Possible Discrepancy Between the Theory and the Observation
astro-phA. Dariush
Photometric and spectroscopic observations and analysis of the eccentric eclipsing binary V459 Cassiopeiae (e=0.0244) were performed by Lacy et al. (2004). Observations of minimum light show the presence of apsidal motion. In order to find the observed rate of apsidal motion, I followed the procedure described by Guinan & Maloney (1985). A new observed rate
Jared C. Bronski, Tom Gambill
We consider the Kuramoto-Sivashinsky (KS) equation in one spatial dimension with periodic boundary conditions. We apply a Lyapunov function argument similar to the one first introduced by Nicolaenko, Scheurer, and Temam, and later improved by Collet, Eckmann, Epstein and Stubbe, and Goodman, to prove that ||u||_2 < C L^1.5. This result is slightly weaker tha
M. Ablikim, BES Collaboration
A partial wave analysis of $χ_{c0}\toπ^+π^-K^+K^-$ in $ψ(2S)\toγχ_{c0}$ decay is presented using a sample of 14 million $ψ(2S)$ events accumulated by the BES II detector. The data are fitted to the sum of relativistic covariant tensor amplitudes for intermediate resonant decay modes. From the fit, significant contributions to $χ_{c0}$ decays from the channel
Coexistence of gapless excitations and commensurate charge-density wave in the 2H-transition metal dichalcogenides
cond-mat.str-elRyan Barnett, Anatoli Polkovnikov, Eugene Demler, Wei-Guo Yin
An unexpected feature common to 2H-transition metal dichalcogenides (2H-TMDs) is revealed with first-principles Wannier functions analysis of the electronic structure of the prototype 2H-TaSe2: The low-energy Ta \red{``$5d_{z^2}$''} bands governing the physics of charge-density wave (CDW) is dominated by hopping between next-nearest neighbors. With t
Masamune Oguri
We present a halo model prediction of the image separation distribution of strong lenses. Our model takes account of the subhalo population, which has been ignored in previous studies, as well as the conventional halo population. Halos and subhalos are linked to central and satellite galaxies by adopting an universal scaling relation between masses of (sub-)
Zhongxi Zhang, C. F. Destefani, Chris McDonald, Thomas Brabec
A 1D model study of charge transport in nano-devices is made by comparing multi-configuration time dependent Hartree-Fock and frozen core calculations. The influence of exchange and Coulomb correlation on the tunneling current is determined. We identify the shape of the tunneling barrier and the resonance structure of the nano-device as the two dominant para
J. S. Milne
We classify the "quotients" of a tannakian category in which the objects of a tannakian subcategory become trivial, and we examine the properties of such quotient categories.
Mahiko Suzuki
It has been argued that the mystery boson X(3872) is a molecule state consisting of primarily D0-D0*bar + D0bar-D*0. In contrast, apparent puzzles and potential difficulties have been pointed out for the charmonium assignment of X(3872). We examine several aspects of these alternatives by semiquantitative methods since quantitatively accurate results are oft
Jessica K. Barrett
We discuss the nonextremal generalisation of the enhancon mechanism. We find that the nonextremal shell branch solution does not violate the Weak Energy Condition when the nonextremality parameter is small, in contrast to earlier discussions of this subject. We show that this physical shell branch solution fills the mass gap between the extremal enhancon sol
Ashok Das, A. Melikyan, Matsuo Sato
We continue the program initiated in hep-th/0411200 and calculate the algebra of the flat currents for the string on AdS_5 x S^5 background in the light-cone gauge with kappa-symmetry fixed. We find that the algebra has a closed form and that the non-ultralocal terms come with a weight factor e^ϕ that depends on the radial AdS_5 coordinate. Based on results
F. A. Barone, L. M. De Moraes, J. A. Helayel-Neto
In this work we calculate the functional generator of the Green's functions of the Kalb-Ramond field in 3+1 dimensions. We also calculate the functional generator, and corresponding Casimir energy, of the same field when it is submitted to boundary conditions on two parallel planes. The boundary conditions we consider can be interpreted as a kind of cond
Thomas Hertog, Stefan Hollands
We study the stability of designer gravity theories, in which one considers gravity coupled to a tachyonic scalar with anti-de Sitter boundary conditions defined by a smooth function W. We construct Hamiltonian generators of the asymptotic symmetries using the covariant phase space method of Wald et al.and find they differ from the spinor charges except when
Y. Wiaux, L. Jacques, P. Vielva, P. Vandergheynst
A fast algorithm is developed for the directional correlation of scalar band-limited signals and band-limited steerable filters on the sphere. The asymptotic complexity associated to it through simple quadrature is of order O(L^5), where 2L stands for the square-root of the number of sampling points on the sphere, also setting a band limit L for the signals
Y. Wiaux, L. Jacques, P. Vandergheynst
A fast and exact algorithm is developed for the spin +-2 spherical harmonics transforms on equi-angular pixelizations on the sphere. It is based on the Driscoll and Healy fast scalar spherical harmonics transform. The theoretical exactness of the transform relies on a sampling theorem. The associated asymptotic complexity is of order O(L^2 log^2_2(L)), where
M. S. Kugeratski, V. P. Goncalves, F. S. Navarra
Perturbative Quantum Chromodynamics (pQCD) predicts that the small-$x$ gluons in a hadron wavefunction should form a Color Glass Condensate (CGC), characterized by a saturation scale $Q_s (x, A)$ which is energy and atomic number dependent. In this paper we study the predictions of CGC physics for electron - ion collisions at high energies. We consider that
Gregor Weihs
Photonic crystals create dramatic new possibilities for nonlinear optics. Line defects are shown to support modes suitable for the production of pairs of photons by the material's second order nonlinearity even if the phase-matching conditions cannot be satisfied in the bulk. These structures offer the flexibility to achieve specific dispersion character
Eric Keto, George Field
We test the hypothesis that the starless cores may be gravitationally bound clouds supported largely by thermal pressure by comparing observed molecular line spectra to theoretical spectra produced by a simulation that includes hydrodynamics, radiative cooling, variable molecular abundance, and radiative transfer in a simple one-dimensional model. The result
Chris Done, Marek Gierlinski
The galactic black hole binary systems give an observational template showing how the accretion flow changes as a function of increasing mass accretion rate, or L/L_Edd. These data can be synthetised with theoretical models of the accretion flow to give a coherent picture of accretion in strong gravity, in which the major hard-soft spectral transition is tri
Philosophy Enters the Optics Laboratory: Bell's Theorem and its First Experimental Tests (1965-1982)
physics.hist-phOlival Freire
This paper deals with the ways that the issue of completing quantum mechanics was brought into laboratories and became a topic in mainstream quantum optics. It focuses on the period between 1965, when Bell published what now we call Bell's theorem, and 1982, when Aspect published the results of his experiments. I argue that what was considered good physi
Nicola Arcozzi, Daniele Morbidelli
In this paper we prove some approximation results for biLipschitz maps in the Heisenberg group. Namely, we show that a biLipschitz map with biLipschitz constant close to one can be pointwise approximated, quantitatively on any fixed ball, by an isometry. This leds to an approximation in BMO norm for the map's Pansu derivative. We also prove that a global
Rajiv Bhat, L. D. Carr, M. J. Holland
Strongly interacting bosons in 2D in a rotating square lattice are investigated via a modified Bose-Hubbard Hamiltonian. Such a system corresponds to a rotating lattice potential imprinted on a trapped Bose-Einstein condensate. Second-order quantum phase transitions between states of different symmetries are observed at discrete rotation rates. For the squar
Jorgen Rasmussen
We study a particular type of logarithmic extension of SL(2,R) Wess-Zumino-Witten models. It is based on the introduction of affine Jordan cells constructed as multiplets of quasi-primary fields organized in indecomposable representations of the Lie algebra sl(2). We solve the simultaneously imposed set of conformal and SL(2,R) Ward identities for two- and t
Hungchong Kim, Yongseok Oh
We perform a QCD sum rule study of the open-charmed $D_s (2317)$ as a four-quark state. Using the diquark-antidiquark picture for the four-quark state, we consider four possible interpolating fields for $D_s (2317)$, namely, scalar-scalar, pseudoscalar-pseudoscalar, vector-vector, and axial-vector--axial-vector types. We test all four currents by constructin
Scott A. Wolpert
The hyperbolic metric for the punctured unit disc in the Euclidean plane is singular at the origin. A renormalization of the metric at the origin is provided by the Euclidean metric. For Riemann surfaces there is a unique germ for the isometry class of a complete hyperbolic metric at a cusp. The renormalization for the punctured unit disc provides a renormal
P. Chigansky
The filtering problem for finite state Markov chains is revisited, when the intensity of the observation noise increases. We give a description of conditional measure concentration around the invariant distribution of the signal and derive asymptotic expressions for the performance indices of the MMSE and MAP filtering estimates.
A. Markowitz
We have characterized the energy-dependent X-ray variability properties of the Seyfert~1 galaxy NGC 3783 using archival XMM-Newton and Rossi X-ray Timing Explorer data. The high-frequency fluctuation power spectral density function (PSD) slope is consistent with flattening towards higher energies. Light curve cross correlation functions yield no significant
Alejandro Perez, Hanno Sahlmann, Daniel Sudarsky
The current understanding of the quantum origin of cosmic structure is discussed critically. We point out that in the existing treatments a transition from a symmetric quantum state to an (essentially classical) non-symmetric state is implicitly assumed, but not specified or analyzed in any detail. In facing the issue we are led to conclude that new physics
Philip Walther, Kevin J. Resch, Caslav Brukner, Anton Zeilinger
All previous tests of local realism have studied correlations between single-particle measurements. In the present experiment, we have performed a Bell experiment on three particles in which one of the measurements corresponds to a projection onto a maximally-entangled state. We show theoretically and experimentally, that correlations between these entangled
Giovanni Panti
MV-algebras can be viewed either as the Lindenbaum algebras of Lukasiewicz infinite-valued logic, or as unit intervals of lattice-ordered abelian groups in which a strong order unit has been fixed. The free n-generated MV-algebra Free_n is representable as an algebra of continuous piecewise-linear functions with integer coefficients over the unit cube [0,1]^
Bahram Mashhoon, Helmut Kaiser
The state of a particle in space and time is characterized by its mass and spin, which therefore determine the inertial properties of the particle. The coupling of intrinsic spin with rotation is examined and the corresponding inertial effects of intrinsic spin are studied. An experiment to measure directly the spin-rotation coupling via neutron interferomet
Jian Dai, Xiao-Jun Wang, Yong-Shi Wu
The LLM's 1/2 BPS solutions of IIB supergravity are known to be closely related to the integer quantum Hall droplets with filling factor $ν=1$, and the giant gravitons in the LLM geometry behave like the quasi-holes in those droplets. In this paper we consider how the fractional quantum Hall effect may arise in this context, by studying the dynamics of g
Eric Keto, Luis C. Ho, K. Y. Lo
We observed the nearby starburst galaxy M82 in CO in the higher frequency (2--1) transition to achieve an angular resolution below 1 arc second or 17 pc at the target. We resolved the molecular gas into a large number of compact clouds, with masses ranging from about 2x10^3 to 2x10^6 solar masses. The mass spectrum scales as N(M) ~ M^-1.5, similar to the mas
M. Chernyakova, A. Lutovinov, J. Rodriguez, M. Revnivtsev
We report on analysis of the poorly studied source 2RXP J130159.6-635806 at different epochs with ASCA, Beppo-SAX, XMM-Newton, and INTEGRAL. The source shows coherent X-ray pulsations at a period ~700s with an average spin up rate of about dnu/dt ~ 2x10^{-13} Hz/s. A broad band (1-60 keV) spectral analysis of 2RXP J130159.6-635806 based on almost simultaneou
C. D. Froggatt, H. B. Nielsen
It is proposed that dark matter could consist of compressed collections of atoms (or metallic matter) encapsulated into, for example, 20 cm big pieces of a different phase. The idea is based on the assumption that there exists at least one other phase of the vacuum degenerate with the usual one. Apart from the degeneracy of the phases we only assume Standard
Yong Zhou
This manuscript has been withdrawn at 17 April, 2007.
Ulrik L. Andersen, Radim Filip, Jaromir Fiurasek, Vincent Josse
We propose a scheme for optimal Gaussian purification of coherent states from several imperfect copies. The proposal is experimentally demonstrated for the case of two copies of a coherent state sent through independent noisy channels. Our purification protocol relies on only linear optics and an ancilla vacuum state, rendering this approach an interesting a
Hirotaka Ito, Shoichi Yamada, Kohsuke Sumiyoshi, Shigehiro Nagataki
We discuss effects of magnetic fields on proto-neutron star winds by performing numerical simulation. We assume that the atmosphere of proto-neutron star has a homogenous magnetic field (ranging from ~10^{12} G to ~10^{15} G) perpendicular to the radial direction and examine the dependence of the three key quantities (dynamical time scale, electron fraction,
Enwei Liang, Bing Zhang
We present the results of a systematical analysis of the intrinsic optical afterglow light curves for a complete sample of gamma-ray bursts (GRBs) observed in the period from Feb. 1997 to Aug. 2005. These light curves are generally well-sampled, with at least four detections in the $R$ band. The redshifts of all the bursts in the sample are available. We der
Xavier Carvajal
This paper has been withdrawn by the author due to a crucial error.
Compositional disorder and its influence on the structural, electronic and magnetic properties of MgC(Ni_{1-x}Co_{x})_{3} alloys using first-principles
cond-mat.mtrl-sciP. Jiji Thomas Joseph, Prabhakar P. Singh
First-principles, density-functional based electronic structure calculations are carried out for MgC(Ni_{1-x}Co_{x})_{3} alloys over the concentration range 0\leq x\leq1, using Korringa-Kohn-Rostoker coherent-potential approximation (KKR CPA) method in the atomic sphere approximation (ASA). The self-consistent calculations are used to study the changes as a
Yuri A. Serebrennikov
In moderately strong magnetic fields, the difference in Lande g-factors in each of the dots of a coupled double quantum dot device may induce oscillations between singlet and triplet states of the entangled electron pair and lead to a nonequilibrium electron spin polarization. We will show that this polarization may partially survive the rapid inhomogeneous
Prateek Sharma, Gregory W. Hammett, Eliot Quataert, James M. Stone
We describe local shearing box simulations of turbulence driven by the magnetorotational instability (MRI) in a collisionless plasma. Collisionless effects may be important in radiatively inefficient accretion flows, such as near the black hole in the Galactic Center. The MHD version of ZEUS is modified to evolve an anisotropic pressure tensor. A fluid closu
David Shih, Xi Yin
Motivated by the recent conjecture of Ooguri, Strominger and Vafa, we compute the semi-canonical partition function of BPS black holes in N=4 and N=8 string theories, to all orders in perturbation theory. Not only are the black hole partition functions surprisingly simple; they capture the full topological string amplitudes, as expected from the OSV conjectu
Lie-Wen Chen, Che Ming Ko, Bao-An Li
Using the relativistic impulse approximation with empirical NN scattering amplitude and the nuclear scalar and vector densities from the relativistic mean-field theory, we evaluate the Dirac optical potential for neutrons and protons in asymmetric nuclear matter. From the resulting Schrö% dinger-equivalent potential, the high energy behavior of the nuclear s
Spin-Wave Relaxation in Diluted Magnetic Semiconductors within the Self-Consistent Green's Function Approach
cond-mat.mtrl-sciJ. E. Bunder, Shih-Jye Sun, Hsiu-Hau Lin
We employ a self-consistent Green's function approach to investigate the spin-wave relaxation Γ(p) in diluted magnetic semiconductors. We find the trend of the spin-wave relaxation strongly depends on the ratio of the itinerant and impurity spin densities. For density ratios in the Ruderman-Kittel-Kasuya-Yosida phase, Γ(p) decreases even though thermal f
L. Petrov, Y. Y. Kovalev, E. Fomalont, D. Gordon
This paper presents the fourth extension to the Very Long Baseline Array (VLBA) Calibrator Survey, containing 258 new sources not previously observed with very long baseline interferometry (VLBI). This survey, based on three 24 hour VLBA observing sessions, fills remaining areas on the sky above declination -40 degrees where the calibrator density is less th
F. M. Cucchietti, J. P. Paz, W. H. Zurek
We examine two exactly solvable models of decoherence -- a central spin-system, (i) with and (ii) without a self--Hamiltonian, interacting with a collection of environment spins. In the absence of a self--Hamiltonian we show that in this model (introduced some time ago to illustrate environment--induced superselection) generic assumptions about the coupling
David R. Mitchell
We present a new approach to quantum computation involving the geometric phase. In this approach, an entire computation is performed by adiabatically evolving a suitably chosen quantum system in a closed circuit in parameter space. The problem solved is the determination of the solubility of a 3-SAT Boolean Satisfiability problem. The problem of non-adiabati
J. Finkelstein
Students Alice and Bob take an examination in their quantum mechanics class, and thereby illustrate some aspects of energy decoherence.
On distinguishability, orthogonality, and violations of the second law: contradictory assumptions, contrasting pieces of knowledge
quant-phP. G. L. Mana, A. Maansson, G. Bjoerk
Two statements by von Neumann and a thought-experiment by Peres prompts a discussion on the notions of one-shot distinguishability, orthogonality, semi-permeable diaphragm, and their thermodynamic implications. In the first part of the paper, these concepts are defined and discussed, and it is explained that one-shot distinguishability and orthogonality are
Kazuya Yuasa, Hiromichi Nakazato
A simple scheme to prepare an entanglement between two separated qubits from a given mixed state is proposed. A single qubit (entanglement mediator) is repeatedly made to interact locally and consecutively with the two qubits through rotating-wave couplings and is then measured. It is shown that we need to repeat this kind of process only three times to esta
Paul Meredith, B. J. Powell, Jennifer Riesz, Stephen Nighswander-Rempel
We discuss recent progress towards the establishment of important structure-property-function relationships in eumelanins - key functional bio-macromolecular systems responsible for photo-protection and immune response in humans, and implicated in the development of melanoma skin cancer. We focus on the link between eumelanin's secondary structure and op
Tommaso Zillio, Igor Volkov, Jayanth R. Banavar, Stephen P. Hubbell
We present an analytically tractable variant of the voter model that provides a quantitatively accurate description of beta-diversity (two-point correlation function) in two tropical forests. The model exhibits novel scaling behavior that leads to links between ecological measures such as relative species abundance and the species area relationship.
Science and exile: David Bohm, the hot times of the Cold War, and his struggle for a new interpretation of quantum mechanics
physics.hist-phOlival Freire
This article focuses on the reception among physicists of Bohm's 1952 papers on the causal interpretation of quantum mechanics, which were poorly received at the time. I describe his Brazilian exile and analyze the culture of physics surrounding the foundations of quantum mechanics. I take into account the strength of the Copenhagen interpretation among
The Road Less Traveled: Non-traditional Ways of Communicating Astronomy with the Public
physics.pop-phMichael J. West
In an age of media saturation, how can astronomers succeed in grabbing the public's attention to increase awareness and understanding of astronomy? Here I discuss some creative alternatives to press releases, public lectures, television programs, books, magazine articles, and other traditional ways of bringing astronomy to a wide audience. By thinking ou
Z. -Y Ma, K. Burnett, M. B. d'Arcy, S. A. Gardiner
We discuss the use of high-order quantum accelerator modes to achieve an atom optical realization of a biased quantum random walk. We first discuss how one can create co-existent quantum accelerator modes, and hence how momentum transfer that depends on the atoms' internal state can be achieved. When combined with microwave driving of the transition betw
Jean Alexandre
A non technical introduction to the concept of renormalization is given, with an emphasis on the energy scale dependence in the description of a physical system. We first describe the idea of scale dependence in the study of a ferromagnetic phase transition, and then show how similar ideas appear in Particle Physics. This short review is written for non-part
Atushi Ishikawa
Employing profits data of Japanese companies in 2002 and 2003, we identify the non-Gibrat's law which holds in the middle profits region. From the law of detailed balance in all regions, Gibrat's law in the high region and the non-Gibrat's law in the middle region, we kinematically derive the profits distribution function in the high and middle r
Goong Chen, Siu A. Chin, Yusheng Dou, Kishore T. Kapale
In this review we first discuss extension of Bohr's 1913 molecular model and show that it corresponds to the large-D limit of a dimensional scaling (D-scaling) analysis, as developed by Herschbach and coworkers. In a separate but synergetic approach to the two-electron problem, we summarize recent advances in constructing analytical models for describing
Reginald T. Cahill
Physics textbooks assert that in the famous interferometer 1887 experiment to detect absolute motion Michelson and Morley saw no rotation-induced fringe shifts - the signature of absolute motion; it was a null experiment. However this is incorrect. Their published data revealed to them the expected fringe shifts, but that data gave a speed of some 8km/s usin
Oscar Bolina
This paper has been withdrawn by the author.
Ilya V. Shadrivov, Andrey A. Sukhorukov, Yuri S. Kivshar
Artificially fabricated structures with periodically modulated parameters such as photonic crystals offer novel ways of controlling the flow of light due to the existence of a range of forbidden frequencies associated with a photonic bandgap. It is believed that modulation of the refractive index in all three spatial dimensions is required to open a complete
Hrayr H. Matevosyan, Anthony W. Thomas, Gerald A. Miller
We explore the suitability of a modern vector meson dominance (VMD) model as a method for chiral extrapolation of nucleon electromagnetic form factor simulations in lattice QCD. It is found that the VMD fits to experimental data can be readily generalized to describe the lattice simulations. However, the converse is not true. That is, the VMD form is unsuita
R. Schiavilla, O. Benhar, A. Kievsky, L. E. Marcucci
The $^3$He$(e,e^\prime p)$$d$ reaction is studied using an accurate three-nucleon bound state wave function, a model for the electromagnetic current operator including one- and two-body terms, and the Glauber approximation for the treatment of final state interactions. In contrast to earlier studies, the profile operator in the Glauber expansion is derived f
V. Yu. Ponomarev, A. I. Vdovin
A recently suggested modified BCS (MBCS) model has been studied at finite temperature. We show that this approach does not allow the existence of the normal (non-superfluid) phase at any finite temperature. Other MBCS predictions such as a negative pairing gap, pairing induced by heating in closed-shell nuclei, and ``superfluid -- super-superfluid''
L. Satpathy
The resonances in $^{12}$C+$^{12}$C system described earlier using long range Morse potential determined from resonance data itself, are reexamined in the light of the recent development of the two new methods for identification of resonances in the scattering theory, namely Imaginary Test Potential and Imaginary Phase-shift methods. The high lying resonance
D. N. Poenaru, R. A. Gherghescu, W. Greiner
The wave function of a spheroidal harmonic oscillator without spin-orbit interaction is expressed in terms of associated Laguerre and Hermite polynomials. The pairing gap and Fermi energy are found by solving the BCS system of two equations. Analytical relationships for the matrix elements of inertia are obtained function of the main quantum numbers and pote
G. Tabacaru, A. Azhari, J. Brinkley, V. Burjan
Measurements of scattering of $^{7}$Be at 87 MeV on a melamine (C$_{3}$N$ _{6}$H$_{6}$) target and of $^{8}$B at 95 MeV on C were performed. For $^{7}$Be the angular range was extended over previous measurements and monitoring of the intensity of the radioactive beam was improved. The measurements allowed us to check and improve the optical model potentials
N. Grion, M. Bregant, P. Camerini, E. Fragiacomo
The results of an extensive campaign of measurements of the pi -> pi pi process in the nucleon and nuclei at intermediate energies are presented. The measurements were motivated by the study of strong pi pi correlations in nuclei. The analysis relies on the composite ratio C_{pi pi}^A, which accounts for the clear effect of the nuclear medium on the (pi pi)
M. V. Ricciardi, P. Armbruster, J. Benlliure, M. Bernas
The production of light and intermediate-mass nuclides formed in the reaction 1H+238U at 1 GeV was measured at the Fragment Separator (FRS) at GSI, Darmstadt. The experiment was performed in inverse kinematics, shooting a 1 A GeV 238U beam on a thin liquid-hydrogen target. 254 isotopes of all elements in the range from Z=7 to Z=37 were unambiguously identifi
K. S. Egiyan, N. B. Dashyan, M. M. Sargsian, M. I. Strikman
The ratios of inclusive electron scattering cross sections of He4, C12 and Fe56 to He3 have been measured at 1 < x_B < 3. At Q^2 > 1.4 GeV^2, the ratios exhibit two separate plateaus, at 1.5 < x_B < 2 and at x_B > 2.25. This pattern is predicted by models that include 2- and 3-nucleon short-range correlations (SRC). Relative to A=3, the per-nucleon probabili
Navot Israeli, Nigel Goldenfeld
We study the predictability of emergent phenomena in complex systems. Using nearest neighbor, one-dimensional Cellular Automata (CA) as an example, we show how to construct local coarse-grained descriptions of CA in all classes of Wolfram's classification. The resulting coarse-grained CA that we construct are capable of emulating the large-scale behavior
T. V. Dudnikova, A. I. Komech, N. J. Mauser
We consider the Dirac equation in $\R^3$ with constant coefficients and study the distribution $μ_t$ of the random solution at time $t\in\R$. It is assumed that the initial measure $μ_0$ has zero mean, a translation-invariant covariance, and finite mean charge density. We also assume that $μ_0$ satisfies a mixing condition of Rosenblatt- or Ibragimov-Linnik-
Semi-classical determination of exponentially small intermode transitions for 1+1 space-time scattering systems
math-phMagali Marx, Alain Joye
We consider the semiclassical limit of systems of autonomous PDE's in 1+1 space-time dimensions in a scattering regime. We assume the matrix valued coefficients are analytic in the space variable and we further suppose that the corresponding dispersion relation admits real-valued modes only with one-dimensional polarization subspaces. Hence a BKW-type an
Viacheslav V. Nikulin, Sachiko Saito
We consider real forms of relatively minimal rational surfaces F_m. Connected components of moduli of real non-singular curves in |-2K_{F_m}| had been classified recently for m=0, 1, 4 in math.AG/0312396. Applying similar methods, here we fill the gap for m=2 and m=3 to complete similar classification for any 0\le m\le 4 when |-2K_{F_m}| is reduced. The case
A. de Carvalho, M. Lyubich, M. Martens
In this paper geometric properties of infinitely renormalizable real Hénon-like maps $F$ in $\R^2$ are studied. It is shown that the appropriately defined renormalizations $R^n F$ converge exponentially to the one-dimensional renormalization fixed point. The convergence to one-dimensional systems is at a super-exponential rate controlled by the average Jacob
R. C. Penner, Dragomir Saric
The punctured solenoid $§$ is an initial object for the category of punctured surfaces with morphisms given by finite covers branched only over the punctures. The (decorated) Teichmüller space of $§$ is introduced, studied, and found to be parametrized by certain coordinates on a fixed triangulation of $§$. Furthermore, a point in the decorated Teichmüller s
Siqi Fu
A smooth bounded pseudoconvex domain in two complex variables is of finite type if and only if the number of eigenvalues of the d-bar-Neumann Laplacian that are less than or equal to $λ$ has at most polynomial growth as $λ$ goes to infinity.
Anish Ghosh
We prove that the convergence Khintchine theorem holds for affine hyperplanes whose parametrizing matrices satisfy a mild Diophantine condition. We use the dynamical method of Kleinbock-Margulis.
Anish Ghosh
We estalish the conjectures of Sprindzhuk over a local field of positive characteristic using the dynamical method of Kleinbock-Margulis.
Elemer E Rosinger
Following our previous work, we suggest here a large class of algebras of scalars in which simultaneous and correlated computations can be performed owing to the existence of surjective algebra homomorphisms. This may replace the currently used traditional computations in which only real or complex scalars are used, or occasionally, nonstandard ones. The usu
Thomas Huettemann
Let X be a pointed connected simplicial set with loop group G. The linearisation map in K-theory as defined by Waldhausen uses G-equivariant spaces. This paper gives an alternative description using presheaves of sets and abelian groups on the simplex category of X. In other words, the linearisation map is defined in terms of X only, avoiding the use of the
Daniel Ryder
A complete classification is presented of elliptic and K3 fibrations birational to certain mildly singular complex Fano 3-folds. Detailed proofs are given for one example case, namely that of a general hypersurface X of degree 30 in weighted P^4 with weights 1,4,5,6,15; but our methods apply more generally. For constructing birational maps from X to elliptic
Sharp estimates for pseudodifferential operators with symbols of limited smoothness and commutators
math.APDavid Lannes
We consider here pseudo-differential operators whose symbol $σ(x,ξ)$ is not infinitely smooth with respect to $x$. Decomposing such symbols into four -sometimes five- components and using tools of paradifferential calculus, we derive sharp estimates on the action of such pseudo-differential operators on Sobolev spaces and give explicit expressions for their
Mathew D. Penrose
Given $n$ independent random marked $d$-vectors $X_i$ with a common density, define the measure $ν_n = \sum_i ξ_i $, where $ξ_i$ is a measure (not necessarily a point measure) determined by the (suitably rescaled) set of points near $X_i$. Technically, this means here that $ξ_i$ stabilizes with a suitable power-law decay of the tail of the radius of stabiliz
Benedicte Haas
This paper introduces stochastic processes that describe the evolution of systems of particles in which particles immigrate according to a Poisson measure and split according to a self-similar fragmentation. Criteria for existence and absence of stationary distributions are established and uniqueness is proved. Also, convergence rates to the stationary distr
The probability of exceeding a high boundary on a random time interval for a heavy-tailed random walk
math.PRSergey Foss, Zbigniew Palmowski, Stan Zachary
We study the asymptotic probability that a random walk with heavy-tailed increments crosses a high boundary on a random time interval. We use new techniques to extend results of Asmussen [Ann. Appl. Probab. 8 (1998) 354-374] to completely general stopping times, uniformity of convergence over all stopping times and a wide class of nonlinear boundaries. We al
A large deviations approach to asymptotically optimal control of crisscross network in heavy traffic
math.PRAmarjit Budhiraja, Arka Prasanna Ghosh
In this work we study the problem of asymptotically optimal control of a well-known multi-class queuing network, referred to as the ``crisscross network,'' in heavy traffic. We consider exponential inter-arrival and service times, linear holding cost and an infinite horizon discounted cost criterion. In a suitable parameter regime, this problem has b
The sizes of the pioneering, lowest crossing and pivotal sites in critical percolation on the triangular lattice
math.PRG. J. Morrow, Y. Zhang
Let L_n denote the lowest crossing of a square 2n\times2n box for critical site percolation on the triangular lattice imbedded in Z^2. Denote also by F_n the pioneering sites extending below this crossing, and Q_n the pivotal sites on this crossing. Combining the recent results of Smirnov and Werner [Math. Res. Lett. 8 (2001) 729-744] on asymptotic probabili
Herbert Lange
An abelian variety admits only a finite number of isomorphism classes of principal polarizations. The paper gives an interpretation of this number in terms of class numbers of definite Hermitian forms in the case of a product of elliptic curves without complex multiplication. In the case of a self-product of an elliptic curve, as well as in the two-dimension
Jianfeng Zhang
In this paper we investigate a class of decoupled forward-backward SDEs, where the volatility of the FSDE is degenerate and the terminal value of the BSDE is a discontinuous function of the FSDE. Such an FBSDE is associated with a degenerate parabolic PDE with discontinuous terminal condition. We first establish a Feynman-Kac type representation formula for
H. Lange, S. Recillas
To any pair of coverings $f_i: X \ra X_i, i = 1,2$ of smooth projective curves one can associate an abelian subvariety of the Jacobian $J_X$, the Prym variety $P(f_1,f_2)$ of the pair $(f_1,f_2)$. In some cases we can compute the type of the restriction of the canonical principal polarization of $JX$. We obtain 2 families of Prym-Tyurin varieties of exponent