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September 2009 arXiv papers — page 3

Showing 201300 of 5,691 papers

  1. Benoit Cerutti, Guillaume Dubus, Gilles Henri

    In gamma-ray binaries such as LS 5039 a large number of electron-positron pairs are created by the annihilation of primary very high energy (VHE) gamma-rays with photons from the massive star. The radiation from these particles contributes to the total high energy gamma-ray flux and can initiate a cascade, decreasing the effective gamma-ray opacity in the sy

  2. Johann Cigler

    Recently I. Mezo studied a simple but interesting generalization of the exponential polynomials. In this note I consider two q-analogues of these polynomials and compute their Hankel determinants.

  3. Shrihari Gopalakrishna

    We discuss the implications of a gauged Abelian hidden-sector communicating with the Standard Model (SM) fields via kinetic mixing with the SM hypercharge gauge field, or via the Higgs quartic interaction. We discuss signatures of the hidden-sector gauge boson at the LHC in the four-lepton channel. We show that a hidden-sector fermion can be a natural dark-m

  4. Miguel A. Perez-Torres

    Core-collapse supernovae are the endproducts of massive stars, and yield radio events whose brightness depends on the intensity of the interaction experienced by the supernova ejecta with the circumstellar presupernova wind material. The fact that CCSNe are intrinsically radio supernovae --albeit with a huge range of different radio powers-- and hence unaffe

  5. Dirk Zerwas

    If supersymmetry is discovered at the LHC, the extraction of the fundamental parameters will be a formidable task. In such a system where measurements depend on different combinations of the parameters in a highly correlated system, the identification of the true parameter set in an efficient way necessitates the development and use of sophisticated methods.

  6. W. A. Zajc

    The new millennium's qualitative advances in relativistic heavy ion physics are in part due to, and are in part causing, a new appreciation for quantitative rigor in both experimental and theoretical work in the field. In these proceedings for the conference-opening "pre-Summary" talk I present an annotated guide to the figures and points made in

  7. Olivier Babelon, Michel Talon, Michel Capdequi Peyranère

    We study the Kowalevski expansions near singularities of the swinging Atwood's machine. We show that there is a infinite number of mass ratios $M/m$ where such expansions exist with the maximal number of arbitrary constants. These expansions are of the so--called weak Painlevé type. However, in view of these expansions, it is not possible to distinguish

  8. Femke Douma

    In 1966, P. Günther proved the following result: Given a continuous function $f$ on a compact surface $M$ of constant curvature -1 and its periodic lift $\tilde{f}$ to the universal covering, the hyperbolic plane, then the averages of the lift $\tilde{f}$ over increasing spheres converge to the average of the function $f$ over the surface $M$. In this articl

  9. Agnieszka Janiuk, Maciej Sznajder, Monika Moscibrodzka, Daniel Proga

    We study a slightly rotating accretion flow onto a black hole, using the fully three dimensional (3-D)numerical simulations. We consider hydrodynamics of an inviscid flow, assuming a spherically symmetric density distribution at the outer boundary and a small, latitude-dependent angular momentum. We investigate the role of the adiabatic index and gas tempera

  10. Gang Mu, Bin Zeng, Peng Cheng, Xiyu Zhu

    Superconductivity at about 15.6 K was achieved in Tb_{1-x}Ca_xFeAsO by partially substituting Tb^{3+} with Ca^{2+} in the nominal doping region x = 0.40 \sim 0.50. A detailed investigation was carried out in a typical sample with doping level of x = 0.44. The upper critical field of this sample was estimated to be 77 Tesla from the magnetic field dependent r

  11. A. Serminato, R. Gallino, C. Travaglio, S. Bisterzo

    We follow the chemical evolution of the Galaxy for the s elements using a Galactic chemical evolution (GCE) model, as already discussed by Travaglio et al. (1999, 2001, 2004), with a full updated network and refined asymptotic giant branch (AGB) models. Calculations of the s contribution to each isotope at the epoch of the formation of the solar system is de

  12. Fedor V. Prigara

    It is shown that the specific heat jump at the superconducting transition temperature in pnictide and cuprate superconductors is produced by ferroelastic fluctuations just below the transition temperature. The amplitude of the corresponding lattice distortion is estimated. It is shown that a contribution from ferroelastic fluctuations to the specific heat ju

  13. Petter Andreas Bergh, Karin Erdmann

    We completely describe the tree classes of the components of the stable Auslander-Reiten quiver of a quantum complete intersection. In particular, we show that the tree class is always $A_{\infty}$ whenever the algebra is of wild representation type. Moreover, in the tame case, there is one component of tree class $\tilde{A}_{12}$, whereas all the other are

  14. J. W. Mei, Z. Y. Weng

    We identify a new kind of elementary excitations, spin-rotons, in the doped Mott insulator. They play a central role in deciding the superconducting transition temperature Tc, resulting in a simple Tc formula,Tc=Eg/6, with Eg as the characteristic energy scale of the spin rotons. We show that the degenerate S=1 and S=0 rotons can be probed by neutron scatter

  15. T. H. Kim, S. -H. Baek, S. M. Yang, S. Y. Jang

    We describe the directional growth of ferroelectric domains in a multiferroic BiFeO3 thin film, which was grown epitaxially on a vicinal (001) SrTiO3 substrate. A detailed structural analysis of the film shows that a strain gradient, which can create a symmetry breaking in a ferroelectric double well potential, causes ferroelectric domains to grow with prefe

  16. E. -M. Laine

    We derive a time-convolutionless master equation for the spin-boson model in the weak coupling limit. The temporarily negative decay rates in the master equation indicate short time memory effects in the dynamics which is explicitly revealed when the dynamics is studied using the non-Markovian jump description. The approach gives new insight into the memory

  17. F. Patat, D. Baade, P. Hoeflich, J. R. Maund

    Using VLT-FORS1 we performed optical spectropolarimetric observations of the Type Ia SN2006X on 7 pre-maximum epochs (day -10 to day -1) and one post-maximum epoch (+39 days). The SN shows strong continuum interstellar polarization reaching about 8% at 4000A, characterized by a wavelength dependency that is substantially different from that of the Milky-Way

  18. Yu. L. Ratis

    It is shown the possibility of existence of metastable atoms of dineutroneum as a bound state of two neutrons and one neutrino. Such atoms can appear in a reaction of deuterons with free or quasi-free electrons. The estimation of mass, size and lifetime of dineutroneum atom is fulfilled.

  19. L. Husti, R. Gallino, S. Bisterzo, O. Straniero

    Barium stars are extrinsic Asymptotic Giant Branch (AGB) stars. They present the s-enhancement characteristic for AGB and post-AGB stars, but are in an earlier evolutionary stage (main sequence dwarfs, subgiants, red giants). They are believed to form in binary systems, where a more massive companion evolved faster, produced the s-elements during its AGB pha

  20. A. Spallicci, S. Aoudia

    Through detection by low gravitational wave space interferometers, the capture of stars by supermassive black holes will constitute a giant step forward in the understanding of gravitation in strong field. The impact of the perturbations on the motion of the star is computed via the tail, the back-scattered part of the perturbations, or via a radiative Green

  21. H. Spreeuw, B. Scheers, R. A. M. J. Wijers

    The 2004 December 27 giant flare from SGR 1806-20 produced a radio nebula that was detectable for weeks. It was observed at a wide range of radio frequencies. We made a total of 19 WSRT observations. Most of these were performed quasi simultaneously at either two or three frequencies, starting 2005 January 4 and ending 2005 January 29. We reobserved the fiel

  22. Michael Baumann, Pierre Mozer, Vincent Daanen, Jocelyne Troccaz

    Computer-assisted prostate biopsies became a very active research area during the last years. Prostate tracking makes it possi- ble to overcome several drawbacks of the current standard transrectal ultrasound (TRUS) biopsy procedure, namely the insufficient targeting accuracy which may lead to a biopsy distribution of poor quality, the very approximate knowl

  23. Luca Belluzzi

    The peculiar three-peak structure of the linear polarization profile shown in the second solar spectrum by the Ba II line at 4554 A has been interpreted as the result of the different contributions coming from the barium isotopes with and without hyperfine structure (HFS). In the same spectrum, a triple peak polarization signal is also observed in the Sc II

  24. Peng-Zhi Huang, Hua-Xing Chen, Shi-Lin Zhu

    We calculate the coupling constants between the light vector mesons and heavy baryons within the framework of the light-cone QCD sum rule in the leading order of heavy quark effective theory. Most resulting sum rules are stable with the variations of the Borel parameter and the continuum threshold. The extracted couplings will be useful in the study of the p

  25. Nguyen D. H. Hai, Lionel Schwartz

    In a preceding article the authors and Tran Ngoc Nam constructed a minimal injective resolution of the mod 2 cohomology of a Thom spectrum. A Segal conjecture type theorem for this spectrum was proved. In this paper one shows that the above mentioned resolutions can be realized topologically. In fact there exists a family of cofibrations inducing short exact

  26. Stephen Coughlan

    We study the extension of a hyperelliptic K3 surface to a Fano 6-fold. This determines a family of surfaces of general type with p_g=1, K^2=2 and hyperelliptic canonical curve, where each surface is a weighted complete intersection inside a Fano 6-fold. Finally, we use these hyperelliptic surfaces to determine an 8-parameter family of Godeaux surfaces with t

  27. Stephen Coughlan

    We give an explicit construction for the extension of a symmetric determinantal quartic K3 surface to a Fano 6-fold. Remarkably, the moduli of the 6-fold extension are in one-to-one correspondence with the moduli of the quartic surface. As a consequence, we determine a 16-parameter family of surfaces of general type with p_g=1 and K^2=2 as weighted complete

  28. D. J. Harding, T. R. Walsh, S. M. Hamilton, W. S. Hopkins

    The geometric structure of the Rh$_8^+$ cation is investigated using a combination of far-infrared multiple photon dissociation spectroscopy and density functional theory (DFT) calculations. The energetic ordering of the different structural motifs is found to depend sensitively on the choice of pure or hybrid exchange functionals. Comparison of experimental

  29. Mariusz Puchalski, Dariusz Kedziera, Krzysztof Pachucki

    We compare the explicitly correlated Hylleraas and exponential basis sets in the evaluations of ground state of Li and Be$^+$. Calculations with Hylleraas functions are numerically stable and can be performed with the large number of basis functions. Our results for ground state energies $-7.478 060 323 910 10(32)$, $-14.324 763 176 790 43(22)$ of Li and Be$

  30. Shu-Chiuan Chang, Lung-Chi Chen

    We derive exactly the number of Hamiltonian paths H(n) on the two dimensional Sierpinski gasket SG(n) at stage $n$, whose asymptotic behavior is given by $\frac{\sqrt{3}(2\sqrt{3})^{3^{n-1}}}{3} \times (\frac{5^2 \times 7^2 \times 17^2}{2^{12} \times 3^5 \times 13})(16)^n$. We also obtain the number of Hamiltonian paths with one end at a certain outmost vert

  31. Han Zhang, Qiaoliang Bao, Dingyuan Tang, Luming Zhao

    Due to its unique electronic property and the Pauli Blocking Principle, atomic layer graphene possesses wavelength-independent ultrafast saturable absorption, which can be exploited for the ultrafast photonics application. Through chemical functionalization, a graphene-polymer nanocomposite membrane was fabricated and firstly used to mode lock a fiber laser.

  32. Mikko Vaananen, Lauri Alha, Juhani Huovelin

    A number of X-ray instruments have been active in observing the solar coronal X-ray radiation this decade. We have compared XSM observations with simultaneous GOES and RHESSI observations. We present flux calibrations for all instruments, and compare XSM and GOES total emission measures (TEM) and temperatures (T). The model-independent flux comparison with X

  33. H. Zhang, D. Y. Tang, L. M. Zhao, Q. L. Bao

    We report on large energy pulse generation in an erbium-doped fiber laser passively mode-locked with atomic layer graphene. Stable mode locked pulses with single pulse energy up to 7.3 nJ and pulse width of 415 fs have been directly generated from the laser. Our results show that atomic layer graphene could be a promising saturable absorber for large energy

  34. N. Marchili, I. Marti-Vidal, A. Brunthaler, T. P. Krichbaum

    We report on a set of 5 GHz Urumqi observations of the galaxy M82, made between August 2005 and May 2009. From the resulting flux densities, we detect a strong flare, starting in March or April and peaking in June 2008. We identify this flare with supernova SN 2008iz. The time sampling of the radio light curve allows us to obtain information on the precursor

  35. Kazuto Oshima

    We exhibit a simple procedure to find how classical signals should be processed in cluster-state quantum computation. Using stabilizers characterizing a cluster state, we can easily find a precise classical signal-flow that is required in performing cluster-state computation.

  36. U. Ott, P. R. Heck, F. Gyngard, R. Wieler

    Knowledge about the age of presolar grains provides important insights into Galactic chemical evolution and the dynamics of grain formation and destruction processes in the Galaxy. Determination from the abundance of cosmic ray interaction products is straightforward, but in the past has suffered from uncertainties in correcting for recoil losses of spallati

  37. Tetsuo Hyodo, Daisuke Jido, Atsushi Hosaka

    The nature of baryon resonances is studied in the dynamical chiral coupled-channel approach for meson-baryon scattering. In general, origin of resonances in two-body scattering can be classified into two categories: dynamically generated states and genuine elementary particles. We demonstrate that the genuine contribution in the loop function can be excluded

  38. Xiaokui Xiao, Guozhang Wang, Johannes Gehrke

    Privacy preserving data publishing has attracted considerable research interest in recent years. Among the existing solutions, {\em $ε$-differential privacy} provides one of the strongest privacy guarantees. Existing data publishing methods that achieve $ε$-differential privacy, however, offer little data utility. In particular, if the output dataset is used

  39. A. V. Rozhkov

    We show that, under rather general assumptions, the phase diagram of a quasi-one-dimensional repulsive Fermi system consists of two ordered phases: the density wave, spin or charge, and the superconductivity. It is demonstrated that the symmetry of the superconducting order parameter is a non-universal property sensitive to microscopic details of the model.

  40. Xiaoming Cai, Liming Guan, Shu Chen, Yajiang Hao

    We study a mixture of $N_{b}$ bosons with point hard-core boson-boson interactions and $N_{f}$ noninteracting spinless fermions with point hard-core boson-fermion interactions in 1D optical lattice with external harmonic confine potential. Using an extended Jordan-Winger transformation (JWT) which maps the hard-core Bose-Fermi mixture into two component noni

  41. Vladimir Baranovsky, Victor Ginzburg, Jeremy Pecharich

    We prove a criterion stating when a line bundle on a smooth coisotropic subvariety Y of a smooth variety X with an algebraic Poisson structure, admits a first order deformation quantization.

  42. Marcos Curty, Tobias Moroder, Xiongfeng Ma, Norbert Lütkenhaus

    We propose a method to prepare different non-Poissonian signal pulses from sources of Poissonian photon number distribution using only linear optical elements and threshold photon detectors. This method allows a simple passive preparation of decoy states for quantum key distribution. We show that the resulting key rates are comparable to the performance of a

  43. Hvedri Inassaridze, Tamaz Kandelaki

    We develop a finite KKG-theory of C*-algebras following Arlettaz- H.Inassaridze's approach to finite algebraic K-theory. The Browder- Karoubi-Lambre's theorem on the orders of the elements for finite algebraic K-theory is extended to finite KKG-theory. A new bivariant theory, called torsion KK-theory is defined as the direct limit of finite KK-theori

  44. Santabrata Das, Sandip K. Chakrabarti, Soumen Mondal

    We investigate the dynamical structure of advective accretion flow around stationary as well as rotating black holes. For a suitable choice of input parameters, such as, accretion rate ($\dot {\cal M}$) and angular momentum ($λ$), global accretion solution may include a shock wave. The post shock flow is located at few tens of Schwarzchild radius and it is g

  45. P. Weltevrede, S. Johnston, R. N. Manchester, R. Bhat

    We report here on two years of timing of 168 pulsars using the Parkes radio telescope. The vast majority of these pulsars have spin-down luminosities in excess of 10^34 erg/s and are prime target candidates to be detected in gamma-rays by the Fermi Gamma-Ray Space Telescope. We provide the ephemerides for the ten pulsars being timed at Parkes which have been

  46. D. Hsieh, Y. Xia, L. Wray, D. Qian

    A topologically ordered material is characterized by a rare quantum organization of electrons that evades the conventional spontaneously broken symmetry based classification of condensed matter. Exotic spin transport phenomena such as the dissipationless quantum spin Hall effect have been speculated to originate from a novel topological order whose identific

  47. Cuizhu Shi, Aditya Ramamoorthy

    The deterministic channel model for wireless relay networks proposed by Avestimehr, Diggavi and Tse `07 has captured the broadcast and inference nature of wireless communications and has been widely used in approximating the capacity of wireless relay networks. The authors generalized the max-flow min-cut theorem to the linear deterministic wireless relay ne

  48. J. R. Trail, R. J. Needs

    Quantum Monte Carlo and quantum chemistry techniques are used to investigate pseudopotential models of the lithium hydride (LiH) molecule. Interatomic potentials are calculated and tested by comparing with the experimental spectroscopic constants and well depth. Two recently-developed pseudopotentials are tested, and the effects of introducing a Li core pola

  49. J. R. Trail

    The combination of continuum Many-Body Quantum physics and Monte Carlo methods provide a powerful and well established approach to first principles calculations for large systems. Replacing the exact solution of the problem with a statistical estimate requires a measure of the random error in the estimate for it to be useful. Such a measure of confidence is

  50. J. R. Trail

    Expectation values of physical quantities may accurately be obtained by the evaluation of integrals within Many-Body Quantum mechanics, and these multi-dimensional integrals may be estimated using Monte Carlo methods. In a previous publication it has been shown that for the simplest, most commonly applied strategy in continuum Quantum Monte Carlo, the random

  51. J. R. Trail, R. J. Needs

    We report smooth relativistic Hartree-Fock pseudopotentials (also known as averaged relativistic effective potentials or AREPs) and spin-orbit operators for the atoms H to Ba and Lu to Hg. We remove the unphysical extremely non-local behaviour resulting from the exchange interaction in a controlled manner, and represent the resulting pseudopotentials in an a

  52. J. R. Trail, R. J. Needs

    We investigate the properties of norm-conserving pseudopotentials (effective core potentials) generated by inversion of the Hartree-Fock equations. In particular we investigate the asymptotic behaviour as $\mathbf{r} \to \infty$ and find that such pseudopotentials are non-local over all space, apart from a few special special cases such H and He. Such extrem

  53. J. R. Trail, D. M. Bird, M. Persson, S. Holloway

    Electron-hole pair creation by an adsorbate incident on a metal surface is described using \textit{ab initio} methods. The approach starts with standard first principles electronic structure theory, and proceeds to combine classical, quantum oscillator and time dependent density functional methods to provide a consistent description of the non-adiabatic ener

  54. Angel R. Lopez-Sanchez, Barbel Koribalski, Janine van Eymeren, Cesar Esteban

    We are obtaining deep multiwavelength data of a sample of nearby blue compact dwarf galaxies (BCDGs) combining broad-band optical/NIR and H$α$ photometry, optical spectroscopy and 21-cm radio observations. Here we present HI results obtained with the Australia Telescope Compact Array for some BCDGs, all showing evident interaction features in their neutral g

  55. J. R. Trail, M. D. Towler, R. J. Needs

    We demonstrate that unrestricted Hartree-Fock theory applied to electrons in a uniform potential has stable Wigner crystal solutions for $r_s \geq 1.44$ in two dimensions and $r_s \geq 4.5$ in three dimensions. The correlation energies of the Wigner crystal phases are considerably smaller than those of the fluid phases at the same density.

  56. J. R. Trail, M. C. Graham, D. M. Bird, M. Persson

    A method is presented for calculating electron-hole pair excitation due to an incident atom or molecule interacting with a metal surface. Energy loss is described using an \textit{ab initio} approach that obtains a position-dependent friction coefficient for an adsorbate moving near a metal surface from a total energy pseudopotential calculation. A semi-clas

  57. J. R. Trail, M. C. Graham, D. M. Bird

    A method for the calculation of the damping rate due to electron-hole pair excitation for atomic and molecular motion at metal surfaces is presented. The theoretical basis is provided by Time Dependent Density Functional Theory (TDDFT) in the quasi-static limit and calculations are performed within a standard plane-wave, pseudopotential framework. The artifi

  58. Lie-Wen Chen, Bao-An Li, Hong-Ru Ma, Jun Xu

    We show that the widely used parabolic approximation to the Equation of State (EOS) of asymmetric nuclear matter leads systematically to significantly higher core-crust transition densities and pressures. Using an EOS for neutron-rich nuclear matter constrained by the isospin diffusion data from heavy-ion reactions in the same sub-saturation density range as

  59. J. R. Trail, D. M. Bird

    One of the goals in the development of large scale electronic structure methods is to perform calculations explicitly for a localised region of a system, while still taking into account the rest of the system outside of this region. An example of this in surface physics would be to embed an adsorbate and a few surface atoms into an extended substrate, hence

  60. K. Tsukiyama, M. Hjorth-Jensen, G. Hagen

    We employ the Gamow shell model (GSM) to describe low-lying states of the oxygen isotopes 24O and 25O. The many-body Schrodinger equation is solved starting from a two-body Hamiltonian defined by a renormalized low-momentum nucleon-nucleon (NN) interaction, and a spherical Berggren basis. The Berggren basis treats bound, resonant, and continuum states on an

  61. J. R. Trail, D. M. Bird

    The constrained electron density method of embedding a Kohn-Sham system in a substrate system (first described by P. Cortona, Phys. Rev. B {\bf 44}, 8454 (1991) and T.A. Wesolowski and A. Warshel, J. Phys. Chem {\bf 97}, 8050 (1993)) is applied with a plane-wave basis and both local and non-local pseudopotentials. This method divides the electron density of

  62. J. R. Trail, D. M. Bird

    A new method is presented for obtaining all-electron results from a pseudopotential calculation. This is achieved by carrying out a localised calculation in the region of an atomic nucleus using the embedding potential method of Inglesfield [J.Phys. C {\bf 14}, 3795 (1981)]. In this method the core region is \emph{reconstructed}, and none of the simplifying

  63. S. Johnston, W. S. Lee, Y. Chen, E. A. Nowadnick

    In this paper we present a review of bosonic renormalization effects on electronic carriers observed from angle-resolved photoemission spectra in the cuprates. We specifically discuss the viewpoint that these renormalizations represent coupling of the electrons to the lattice, and review how the wide range of materials dependence, such as the number of CuO$_

  64. J. R. Trail, D. M. Bird

    Highly accurate experimental structure factors of silicon are available in the literature, and these provide the ideal test for any \emph{ab initio} method for the construction of the all-electron charge density. In a recent paper [J. R. Trail and D. M. Bird, Phys. Rev. B {\bf 60}, 7863 (1999)] a method has been developed for obtaining an accurate all-electr

  65. Zhiwei Yun, Xinwen Zhu

    Let K be a connected compact Lie group, and G be its complexification. The homology of the based loop group ΩK with integer coefficients is naturally a \ZZ-Hopf algebra. After possibly inverting 2 or 3, we identify H_*(ΩK,\ZZ) with the Hopf algebra of algebraic functions on B^\vee_e, where B^\vee is a Borel subgroup of the Langlands dual group scheme G^\vee

  66. Hiroshi Itoyama, Kazunobu Maruyoshi, Syoji Minato

    We consider low energy processes described by the N=2 supercurrent on its partially (to N=1) and spontaneously broken vacuum and the attendant Nambu-Goldstone fermion (NGF), which the presence of the electric and magnetic Fayet-Iliopoulos (FI) terms is responsible for. We show suppressions of amplitudes decaying into the NGF as its momentum becomes small. In

  67. M. R. Robilotta

    Three instances are discussed in which results produced by chiral perturbation theory can be reliably pushed to high space-like values of transferred momenta: 1. nuclear interactions, 2. nucleon sigma-term and 3. space-like structure of the pion

  68. Leping Li, Jun Zhang

    Flare ribbons are always dynamic, and sometimes sweep across sunspots. Examining 588 (513 M-class and 75 X-class) flare events observed by Transition Region and Coronal Explorer (TRACE) satellite and Hinode Solar Optical Telescope (SOT) from 1998 May to 2009 May, we choose the event displaying that one of the flare ribbons completely sweeps across the umbra

  69. Evangelos Markakis, Ioannis Milis

    ACAC 2009 is organized by the Athens University of Economics and Business (AUEB) and it is the fourth in a series of meetings that aim to bring together researchers working on all areas of the theory of algorithms and computational complexity. These meetings are expected to serve as a lively forum for presenting results that are in a preliminary stage or hav

  70. Manuele Santoprete, Cristina Stoica

    Consider the motion of a material point of unit mass in a central field determined by a homogeneous potential of the form $(-1/r^α)$, $α>0,$ where $r$ being the distance to the centre of the field. Due to the singularity at $r=0,$ in computer-based simulations, usually, the potential is replaced by a similar potential that is smooth, or at least continuous.

  71. K. Kusakabe, K. Harada, Y. Ikuno, H. Nagara

    Stable oxygen sites on a PdO film over a Pd(100) thin structures with a (sqrt{5} times sqrt{5}) R27^circ surface-unit cell are determined using the first-principles electronic structure calculations with the generalized gradient approximation. The adsorbed monatomic oxygen goes to a site bridging two 2-fold-coordinated Pd atoms or to a site bridging a 2-fold

  72. Chao-Jun Feng, Xin-Zhou Li

    The class of Chaplygin gas models regarded as a candidate of dark energy can be realized by a scalar field, which could drive the variation of the fine structure constant $α$ during the cosmic time. This phenomenon has been observed for almost ten years ago from the quasar absorption spectra and attracted many attentions. In this paper, we reconstruct the cl

  73. Koichi Kusakabe

    We propose a possible charge fluctuation effect expected in layered superconducting materials. In the multireference density functional theory, relevant fluctuation channels for the Josephson coupling between superconducting layers include the interlayer pair hopping derived from the Coulomb repulsion. When interlayer single-electron tunneling processes are

  74. Mu-Chun Chen, K. T. Mahanthappa, Felix Yu

    We propose a Randall-Sundrum model with a bulk family symmetry based on the double tetrahedral group, T', which generates the tri-bimaximal neutrino mixing pattern and a realistic CKM matrix. The T' symmetry forbids tree-level flavor-changing-neutral-currents in both the quark and lepton sectors, as different generations of fermions are unified into

  75. Derrick Hart, Liangpan Li, Chun-Yen Shen

    In this paper the authors study set expansion in finite fields. Fourier analytic proofs are given for several results recently obtained by Solymosi, Vinh and Vu using spectral graph theory. In addition, several generalizations of these results are given. In the case that $A$ is a subset of a prime field $\mathbb F_p$ of size less than $p^{1/2}$ it is shown t

  76. Mu-Chun Chen, K. T. Mahanthappa

    We propose the complex group theoretical Clebsch-Gordon coefficients as a novel origin of CP violation. This is manifest in our model based on SU(5) combined with the double tetrahedral group, T'. Due to the presence of the doublet representations in $T^{\prime}$, there exist complex CG coefficients, leading to explicit CP violation in the model, while t

  77. Nathan Killoran, Devon N. Biggerstaff, Rainer Kaltenbaek, Kevin J. Resch

    Remote state preparation (RSP) is the act of preparing a quantum state at a remote location without actually transmitting the state itself. Using at most two classical bits and a single shared maximally entangled state, one can in theory remotely prepare any qubit state with certainty and with perfect fidelity. However, in any experimental implementation the

  78. Qingqing Sun, M. Selim Shahriar, M. Suhail Zubairy

    We analyze the effects of noise and parameter deviations in a bichromatic Raman type white light cavity, with potential applications in precision measurements such as gravitational wave detection. The results show that the dispersion variation induced by parameter deviation can be controlled within $10^{-4}$. The laser phase noise decreases the dispersion ma

  79. Sebastien Boyaval, Tony Lelievre

    In this work, we develop a reduced-basis approach for the efficient computation of parametrized expected values, for a large number of parameter values, using the control variate method to reduce the variance. Two algorithms are proposed to compute online, through a cheap reduced-basis approximation, the control variates for the computation of a large number

  80. Quan M. Nguyen, Avner Peleg

    We study the deterministic effects of Raman-induced crosstalk in amplified wavelength division multiplexing (WDM) optical fiber transmission lines. We show that the dynamics of pulse amplitudes in an N-channel transmission system is described by an N-dimensional predator-prey model. We find the equilibrium states with non-zero amplitudes and prove their stab

  81. V. D. Ivashchuk

    The (n +1)-dimensional Einstein-Gauss-Bonnet (EGB) model is considered. For diagonal cosmological metrics, the equations of motion are written as a set of Lagrange equations with the effective Lagrangian containing two "minisuperspace" metrics on R^n: a 2-metric of pseudo-Euclidean signature and a Finslerian 4-metric proportional to the n-dimensional

  82. E. Shaked, O. Michailovich

    The problem of reconstruction of digital images from their degraded measurements is regarded as a problem of central importance in various fields of engineering and imaging sciences. In such cases, the degradation is typically caused by the resolution limitations of an imaging device in use and/or by the destructive influence of measurement noise. Specifical

  83. Rupert L. Frank, Elliott H. Lieb, Robert Seiringer

    We show that, under very general definitions of a kinetic energy operator $T$, the Lieb-Thirring inequalities for sums of eigenvalues of $T-V$ can be derived from the Sobolev inequality appropriate to that choice of $T$.

  84. A. V. Samokhvalov

    The current-phase relation (CPR) for a short Josephson junction placed in the nonuniform field of a small ferromagnetic particle is studied. The effect of the particle produced on the junction appears to be strong due to the formation of the pair of oppositely directed Abrikosov vortices which pierce the thin film superconducting electrode and cause a small-

  85. Benoit Fresse

    The category of pruned trees has been defined by M. Batanin with the aim of understanding the cell structure of certain E_n-operads in categorical terms. The objects of this category are planar trees with n levels so that all leaves are at the top level of the tree. The goal of this article is to prove that the category of pruned trees is Koszul. This result

  86. Joey Wilson, Neal Patwari

    This paper presents a new method for imaging, localizing, and tracking motion behind walls in real-time. The method takes advantage of the motion-induced variance of received signal strength measurements made in a wireless peer-to-peer network. Using a multipath channel model, we show that the signal strength on a wireless link is largely dependent on the po

  87. Sheldon Stone, Liming Zhang

    We show that the decay Bs -> J/psi f0(980), f0(980)->pi+ pi- can be used to measure the CP violating phase in Bs mixing, -2β_s, and estimate the sensitivity as +/- 0.050 rad, for 2/fb of LHCb data. After adding in the related Bs -> J/psi eta', η' -> rho gamma mode, the sensitivity improves to +/- 0.044 rad. Use of these CP eigenstates obviates the ne

  88. Andrew Randono

    We exploit an interpretation of gravity as the symmetry broken phase of a de Sitter gauge theory to construct new solutions to the first order field equations. The new solutions are constructed by performing large $Spin(4,1)$ gauge transformations on the ordinary de Sitter solution and extracting first the tetrad, then the induced metric. The class of metric

  89. Michael Aizenman, Simone Warzel

    We present some recent results concerning the persistence of dynamical localization for disordered systems of n particles under weak interactions.

  90. Marcela Carena, Kyoungchul Kong, Eduardo Ponton, Jose Zurita

    We consider supersymmetric models that include particles beyond the Minimal Supersymmetric Standard Model (MSSM) with masses in the TeV range, and that couple significantly to the MSSM Higgs sector. We perform a model-independent analysis of the spectrum and couplings of the MSSM Higgs fields, based on an effective theory of the MSSM degrees of freedom. The

  91. Raman Sundrum

    We study the phenomenon of accidental or "emergent" supersymmetry within gauge theory and connect it to the scenarios of Split Supersymmetry and Higgs compositeness. Combining these elements leads to a significant refinement and extension of the proposal of Partial Supersymmetry, in which supersymmetry is broken at very high energies but with a remna

  92. Imran Ahmed

    We recall first some basic facts on weighted homogeneous functions and filtrations in the ring $A$ of formal power series. We introduce next their analogues for weighted homogeneous diffeomorphisms and vector fields. We show that the Milnor algebra is a complete invariant for the classification of weighted homogeneous polynomials with respect to right-equiva

  93. Prateek Sharma, Phillip Colella, Daniel F. Martin

    The equation governing the streaming of a quantity down its gradient superficially looks similar to the simple constant velocity advection equation. In fact, it is the same as an advection equation if there are no local extrema in the computational domain or at the boundary. However, in general when there are local extrema in the computational domain it is a

  94. Jun-Hwan Choi, Kentaro Nagamine

    We investigate the effects of the change of cosmological parameters and star formation (SF) models on the cosmic SF history using cosmological smoothed particle hydrodynamics (SPH) simulations based on the cold dark matter (CDM) model. We vary the cosmological parameters within 1-sigma error from the WMAP best-fit parameters, and find that such changes in co

  95. Chinmay S. Vaze, Mahesh K. Varanasi

    The degrees of freedom (DoF) regions are characterized for the multiple-input multiple-output (MIMO) broadcast channel (BC), interference channels (IC) (including X and multi-hop interference channels) and the cognitive radio channel (CRC), when there is perfect and no channel state information at the receivers and the transmitter(s) (CSIR and CSIT), respect

  96. Leonardo Modesto, Isabeau Prémont-Schwarz

    In this paper we have recalled the semiclassical metric obtained from a classical analysis of the loop quantum black hole (LQBH). We show that the regular Reissner-Nordström-like metric is self-dual in the sense of T-duality: the form of the metric is invariant under the exchange r -> a0/r where a0 is proportional to the minimum area in LQG. Of particular in

  97. Carlos R. Mafra

    We use the pure spinor formalism to obtain the supersymmetric massless five-point amplitude at tree-level in a streamlined fashion. We also prove the equivalence of an OPE identity in string theory with a subset of the Bern-Carrasco-Johansson five-point kinematic relations, and demonstrate how the remaining BCJ identities follow from the different integratio

  98. Li-Sheng Tseng, Shing-Tung Yau

    We introduce new finite-dimensional cohomologies on symplectic manifolds. Each exhibits Lefschetz decomposition and contains a unique harmonic representative within each class. Associated with each cohomology is a primitive cohomology defined purely on the space of primitive forms. We identify the dual currents of lagrangians and more generally coisotropic s

  99. Rutger Dungan, Harrison B. Prosper

    The observation that Type Ia supernovae are fainter than expected given their red shifts has led to the conclusion that the expansion of the universe is accelerating. The widely accepted hypothesis is that this acceleration is caused by a cosmological constant or, more generally, some dark energy field that pervades the universe. This hypothesis presents a c

  100. Analia Zwick, Omar Osenda

    One spin excitation states are involved in the transmission of quantum states and entanglement through a quantum spin chain, the localization properties of these states are crucial to achieve the transfer of information from one extreme of the chain to the other. We investigate the bipartite entanglement and localization of the one excitation states in a qua