June 2009 arXiv papers — page 4
Showing 301–400 of 5,471 papers
M. L. Glasser, M. Gadella, L. M. Nieto
We study a one-dimensional singular potential plus three types of regular interactions: constant electric field, harmonic oscillator and infinite square well. We use the Lippman-Schwinger Green function technique in order to search for the bound state energies. In the electric field case the unique bound state coincides with that found in an earlier study as
The D0 Collaboration, V. M. Abazov
We present a search for charged Higgs bosons in decays of top quarks, in the mass range $80 < m_{H^{\pm} < 155$ GeV, assuming the subsequent decay $H^{+} \to τ^{+} ν_τ$ (and its charge conjugate). Using 0.9 fb$^{-1}$ of lepton+jets data collected with the D0 detector at the Fermilab Tevatron $p\bar{p}$ collider, operating at a center of mass energy $\sqrt{s}
Andreas Ruttor, Manfred Opper
We address the problem of estimating unknown model parameters and state variables in stochastic reaction processes when only sparse and noisy measurements are available. Using an asymptotic system size expansion for the backward equation we derive an efficient approximation for this problem. We demonstrate the validity of our approach on model systems and ge
Rui Pedro Carpentier
Eliahou \cite{2} and Kryuchkov \cite{9} conjectured a proposition that Gravier and Payan \cite{4} proved to be equivalent to the Four Color Theorem. It states that any triangulation of a polygon can be transformed into another triangulation of the same polygon by a sequence of signed diagonal flips. It is well known that any pair of polygonal triangulations
Alessandro Ruzzi
We describe the effective and the big cones of a projective symmetric variety. Moreover, we give a necessary and sufficient combinatorial criterion for the bigness of a nef divisor on a projective symmetric variety. When the variety is toroidal and the divisor is $G$-stable, such criterion has an explicit geometric interpretation. Finally, we describe the sp
Alisdair O. G. Wallis, Jeremy M. Hutson
We carry out calculations on $M$-changing collisions of NH ($^3Σ^-$) molecules in magnetically trappable states using a recently calculated potential energy surface. We show that elastic collision rates are much faster than inelastic rates for a wide range of fields at temperatures up to 10 mK and that the ratio increases for lower temperatures and magnetic
Daniel E. Sheehy, Joerg Schmalian
The observed 97.7% optical transparency of graphene has been linked to the value 1/137 of the fine structure constant, by using results for noninteracting Dirac fermions. The agreement in three significant figures requires an explanation for the apparent unimportance of the Coulomb interaction. Using arguments based on Ward identities, the leading correction
On the imaginary part of the next-to-leading-order static gluon self-energy in an anisotropic plasma
hep-phM. E. Carrington, A. Rebhan
Using hard-loop (HL) effective theory for an anisotropic non-Abelian plasma, which even in the static limit involves nonvanishing HL vertices, we calculate the imaginary part of the static next-to-leading-order gluon self energy in the limit of a small anisotropy and with external momentum parallel to the anisotropy direction. At leading order, the static pr
Families of Canonical Transformations by Hamilton-Jacobi-Poincaré equation. Application to Rotational and Orbital Motion
nlin.SISebastián Ferrer, Martin Lara
The Hamilton-Jacobi equation in the sense of Poincaré, i.e. formulated in the extended phase space and including regularization, is revisited building canonical transformations with the purpose of Hamiltonian reduction. We illustrate our approach dealing with orbital and attitude dynamics. Based on the use of Whittaker and Andoyer symplectic charts, for whic
Marius Junge, Quanhua Xu
Following Grothendieck's characterization of Hilbert spaces we consider operator spaces $F$ such that both $F$ and $F^*$ completely embed into the dual of a C*-algebra. Due to Haagerup/Musat's improved version of Pisier/Shlyakhtenko's Grothendieck inequality for operator spaces, these spaces are quotients of subspaces of the direct sum $C\oplus R
Éric Ricard, Quanhua Xu
Let $\mathcal{M}$ be a semifinite von Neumann algebra equipped with a semifinite normal faithful trace $τ$. Let $d$ be an injective positive measurable operator with respect to $(\mathcal{M}, τ)$ such that $d^{-1}$ is also measurable. Define $$L_p(d)={x\in L_0(\mathcal{M}) : dx+xd\in L_p(\mathcal{M})}\quad{and}\quad \|x\|_{L_p(d)}=\|dx+xd\|_p .$$ We show tha
Julien Grivaux
This paper has been replaced by the papers arXiv:1001.0114 and arXiv:1001.0119
Hidefumi Ohsugi
Sturmfels-Sullivant conjectured that the cut polytope of a graph is normal if and only if the graph has no K_5 minor. In the present paper, it is proved that the normality of cut polytopes of graphs is a minor closed property. By using this result, we have large classes of normal cut polytopes. Moreover, it turns out that, in order to study the conjecture, i
Sebastien Galais, James Kneller, Cristina Volpe, Jerome Gava
We investigate shock wave effects upon the diffuse supernova neutrino background using dynamic profiles taken from hydrodynamical simulations and calculating the neutrino evolution in three flavors with the S-matrix formalism. We show that the shock wave impact is significant and introduces modifications of the relic fluxes by about $20 \%$ and of the associ
From 0 to 5000 in $2\times 10^{-24}$ seconds: Entropy production in relativistic heavy-ion collisions
nucl-thR. J. Fries, T. Kunihiro, B. Müller, A. Ohnishi
We review what is known about the contributions to the final entropy from the different stages of a relativistic nuclear collision, including recent results on the decoherence entropy and the entropy produced during the hydrodynamic phase by viscous effects. We then present a general framework, based on the Husimi distribution function, for the calculation o
E. M. Shahverdiev, K. A. Shore
We report on partial and global generalized synchronization in exemplar bidirectionally coupled non-identical chaotic systems with multiple time delays. We derive conditions for such synchronization regimes. The general approach is applied to the case of multiple time delay laser systems with electro-optical feedback. We also study the effect of signal sampl
Ugo Boscain, Grégoire Charlot, Francesco Rossi
In this paper we consider the problem of reconstructing a curve that is partially hidden or corrupted by minimizing the functional $\int \sqrt{1+K_γ^2} ds$, depending both on length and curvature $K$. We fix starting and ending points as well as initial and final directions. For this functional we discuss the problem of existence of minimizers on various fun
Gunther Cornelissen, Oliver Lorscheid
The space of toroidal automorphic forms was introduced by Zagier in the 1970s: a GL_2-automorphic form is toroidal if it has vanishing constant Fourier coefficients along all embedded non-split tori. The interest in this space stems (amongst others) from the fact that an Eisenstein series of weight s is toroidal for a given torus precisely if s is a non-triv
X. Y. Sun, D. Q. Fang, Y. G. Ma, X. Z. Cai
The dependence between neutron-to-proton yield ratio ($R_{np}$) and neutron skin thickness ($δ_{np}$) in neutron-rich projectile induced reactions is investigated within the framework of the Isospin-Dependent Quantum Molecular Dynamics (IQMD) model. The density distribution of the Droplet model is embedded in the initialization of the neutron and proton dens
U. Langenfeld, S. Moch, P. Uwer
We present the first direct determination of the running top-quark mass based on the total cross section of top-quark pair-production as measured at the Tevatron. Our theory prediction for the cross section includes various next-to-next-to-leading order QCD contributions, in particular all logarithmically enhanced terms near threshold, the Coulomb correction
Mathieu Colin, Louis Jeanjean, Marco Squassina
We study a class of quasi-linear Schrödinger equations arising in the theory of superfluid film in plasma physics. First, using gauge transforms and a derivation process we solve, under some regularity assumptions, the Cauchy problem. Then, by means of variational methods, we study the existence, the orbital stability and instability of standing waves which
Kentaro Saji
We give useful and simple criteria for determining D_4 singularities of wave fronts. As an application, we investigate behaviors of singular curvatures of cuspidal edges near D_4^+ singularities.
Elsa Prada, Pablo San-Jose, Gladys León, Michael M. Fogler
Graphene membranes suspended off electric contacts or other rigid supports are prone to elastic strain, which is concentrated at the edges and corners of the samples. Such a strain leads to an algebraically varying effective magnetic field that can reach a few Tesla in sub-micron wide flakes. In the quantum Hall regime the interplay of the effective and the
Takafumi Shibuta
We prove that the defining ideal of a sufficiently high Veronese subring of a toric algebra admits a quadratic Gröbner basis consisting of binomials. More generally, we prove that the defining ideal of a sufficiently high Veronese subring of a standard graded ring admits a quadratic Gröbner basis. We give a lower bound on $d$ such that the defining ideal of
Remigiusz Augusiak, Maciej Lewenstein
While the experimental detection of entanglement provides already quite a difficult task, experimental quantification of entanglement is even more challenging, and has not yet been studied thoroughly. In this paper we discuss several issues concerning bounds on concurrence measurable collectively on copies of a given quantum state. Firstly, we concentrate on
E. A. Chekhovich, M. N. Makhonin, K. V. Kavokin, A. B. Krysa
We demonstrate that efficient optical pumping of nuclear spins in semiconductor quantum dots (QDs) can be achieved by resonant pumping of optically "forbidden" transitions. This process corresponds to one-to-one conversion of a photon absorbed by the dot into a polarized nuclear spin, which also has potential for initialization of hole spin in QDs. P
B. Steinke, T. Jogler, D. Borla Tridon
The Imaging Atmospheric Cherenkov Telescope MAGIC I has recently been extended to a stereoscopic system by adding a second 17 m telescope, MAGIC-II. One of the major improvements of the second telescope is an improved camera. The Camera Control Program is embedded in the telescope control software as an independent subsystem. The Camera Control Program is an
R. M. Wagner, I. Donnarumma, J. Grube, M. Villata
We present optical to very-high energy (VHE) gamma-ray observations of Mrk 421 between 2008 May 24 and June 23. A high-energy (HE) gamma-ray signal was detected by AGILE-GRID during June 9-15, brighter than the average flux observed by EGRET in Mrk 421 by a factor of approx. 1.5. In 20-60 keV X-rays, a large-amplitude 5-day flare (June 9-15) was resolved wit
Alexey Zaytsev, Gary McGuire
In this paper we derive a recursion for the zeta function of each function field in the second Garcia-Stichtenoth tower when $q=2$. We obtain our recursion by applying a theorem of Kani and Rosen that gives information about the decomposition of the Jacobians. This enables us to compute the zeta functions explicitly of the first six function fields.
Jean-Michel Vallin
Generalizing the notion of matched pair of groups, we define and study matched pairs of locally compact groupoids endowed with Haar systems, in order to give new examples of measured quantum groupoids.
Oleksiy Kashuba, Vladimir I. Fal'ko
Inelastic light scattering from Dirac-type electrons in graphene is shown to be dominated by the generation of the inter-band electronic modes which are odd in terms of time-inversion symmetry and belong to the irreducible representation A$_2$ of the point group C$_{6v}$ of the honeycomb crystal. At high magnetic fields, these electron-hole excitations appea
Anton S. Galaev
Possible irreducible holonomy algebras $\g\subset\osp(p,q|2m)$ of Riemannian supermanifolds under the assumption that $\g$ is a direct sum of simple Lie superalgebras of classical type and possibly of a one-dimensional center are classified. This generalizes the classical result of Marcel Berger about the classification of irreducible holonomy algebras of ps
Jin-Wu Jiang, Jian-Sheng Wang, Baowen Li
The Young's modulus of graphene is investigated through the intrinsic thermal vibration in graphene which is `observed' by molecular dynamics, and the results agree quite well with the recent experiment [Science \textbf{321}, 385 (2008)]. This method is further applied to show that the Young's modulus of graphene: 1. increases with increasing siz
Hansjörg Geiges, András I. Stipsicz
Two constructions of contact manifolds are presented: (i) products of S^1 with manifolds admitting a suitable decomposition into two exact symplectic pieces and (ii) fibre connected sums along isotropic circles. Baykur has found a decomposition as required for (i) for all closed, oriented 4-manifolds. As a corollary, we can show that all closed, oriented 5-m
A. A. Vasiliev, S. V. Dmitriev, A. E. Miroshnichenko
We overview the basic concepts, models, and methods related to the multi-field continuum theory of solids with complex structures. The multi-field theory is formulated for structural solids by introducing a macrocell consisting of several primitive cells and, accordingly, by increasing the number of vector fields describing the response of the body to extern
Y. Yan, K. Khosonthongkee, C. Kobdaj, P. Suebka
The reactions of electron-positron to nucleon-antinucleon pair at energy threshold are studied in a non-perturbative quark model. The puzzling experimental result that the ratio of the cross section of electron-positron to proton-antiproton to the one of electron-positron to neutron-antineutron is smaller than 1 can be understood in the framework of the phen
Graham S. Hall, David P. Lonie
A study is made of 4-dimensional Lorentz manifolds which are projectively related, that is, whose Levi-Civita connections give rise to the same (unparameterised) geodesics. A brief review of some relevant recent work is provided and a list of new results connecting projective relatedness and the holonomy type of the Lorentz manifold in question is given. Thi
Laurent Chevillard, Raoul Robert, Vincent Vargas
Based on the mechanics of the Euler equation at short time, we show that a Recent Fluid Deformation (RFD) closure for the vorticity field, neglecting the early stage of advection of fluid particles, allows to build a 3D incompressible velocity field that shares many properties with empirical turbulence, such as the teardrop shape of the R-Q plane. Unfortunat
Peter J. Forrester, Manjunath Krishnapur
A result of Zyczkowski and Sommers [J.Phys.A, 33, 2045--2057 (2000)] gives the eigenvalue probability density function for the top N x N sub-block of a Haar distributed matrix from U(N+n). In the case n \ge N, we rederive this result, starting from knowledge of the distribution of the sub-blocks, introducing the Schur decomposition, and integrating over all
The CDF Collaboration, T. Aaltonen
We present an analysis of the mass of the X(3872) reconstructed via its decay to J/psi pi+ pi- using 2.4 fb^-1 of integrated luminosity from ppbar collisions at sqrt(s) = 1.96 TeV, collected with the CDF II detector at the Fermilab Tevatron. The possible existence of two nearby mass states is investigated. Within the limits of our experimental resolution the
$α_s$ from $τ$ decays: contour-improved versus fixed-order summation in a new QCD perturbation expansion
hep-phIrinel Caprini, Jan Fischer
We consider the determination of $α_s$ from $τ$ hadronic decays, by investigating the contour-improved (CI) and the fixed-order (FO) renormalization group summations in the frame of a new perturbation expansion of QCD, which incorporates in a systematic way the available information about the divergent character of the series. The new expansion functions, wh
Ville Keranen, Esko Keski-Vakkuri, Sean Nowling, K. P. Yogendran
We construct dark soliton solutions in a holographic model of a relativistic superfluid. We study the length scales associated with the condensate and the charge density depletion, and find that the two scales differ by a non-trivial function of the chemical potential. By adjusting the chemical potential, we study the variation of the depletion of charge den
Luigi Fontana, Carlo Morpurgo
In 1988 Adams obtained sharp Moser-Trudinger inequalities on bounded domains of R^n. The main step was a sharp exponential integral inequality for convolutions with the Riesz potential. In this paper we extend and improve Adams' results to functions defined on arbitrary measure spaces with finite measure. The Riesz fractional integral is replaced by gene
Electroweak two-loop contribution to the mass splitting within a new heavy SU(2)$_L$ fermion multiplet
hep-phYouichi Yamada
New heavy particles in an SU(2)_L multiplet, sometimes introduced in extensions of the standard model, have highly degenerate tree-level mass M if their couplings to the Higgs bosons are very small or forbidden. However, loop corrections may generate the gauge-symmetry-breaking mass splitting within the multiplet, which does not vanish in the large M limit d
Zero modes, energy gap, and edge states of anisotropic honeycomb lattice in a magnetic field
cond-mat.mes-hallKenta Esaki, Masatoshi Sato, Mahito Kohmoto, Bertrand I. Halperin
We present systematic study of zero modes and gaps by introducing effects of anisotropy of hopping integrals for a tight-binding model on the honeycomb lattice in a magnetic field. The condition for the existence of zero modes is analytically derived. From the condition, it is found that a tiny anisotropy for graphene is sufficient to open a gap around zero
Shoji Yokura
The Milnor class is a generalization of the Milnor number, defined as the difference (up to sign) of Chern--Schwartz--MacPherson's class and Fulton--Johnson's canonical Chern class of a local complete intersection variety in a smooth variety. In this paper we introduce a "motivic" Grothendieck group $K^{\mathcal Prop}_{\ell.c.i}(\mathcal V/X
Calabi-Yau structures and Einstein-Sasakian structures on crepant resolutions of isolated singularities
math.DGRyushi Goto
Let $X_0$ be an affine variety with only normal isolated singularity $p$ and $π: X\to X_0$ a smooth resolution of the singularity with trivial canonical line bundle $K_X$. If the complement of the affine variety $X_0\backslash\{p\}$ is the cone $C(S)=\Bbb R_{>0}\times S$ of an Einstein-Sasakian manifold $S$, we shall prove that the crepant resolution $X$ of
Simant Dube
We provide geometrical interpretation of the Master Theorem to solve divide-and-conquer recurrences. We show how different cases of the recurrences correspond to different kinds of fractal images. Fractal dimension and Hausdorff measure are shown to be closely related to the solution of such recurrences.
Nikolai V. Ivanov
The proof of Brouwer's fixed-point theorem based on Sperner's lemma is often presented as an elementary combinatorial alternative to advanced proofs based on algebraic topology. The goal of this note is to show that: (i) the combinatorial proof of Sperner's Lemma can be considered as a cochain-level version, written in the combinatorial language, of a standa
Shinji Mukohyama
There are at least four versions of Horava-Lishitz gravity in the literature. We consider the version without the detailed balance condition with the projectability condition and address one aspect of the theory: avoidance of caustics for constant time hypersurfaces. We show that there is no caustic with plane symmetry in the absence of matter source if λ\ne
Heesang Park, Jongil Park, Dongsoo Shin
In this paper we construct a new family of simply connected minimal complex surfaces of general type with $p_g=1$, $q=0$, and $K^2=3, 4, 5, 6, 8$ using a $\mathbb{Q}$-Gorenstein smoothing theory. We also reconstruct minimal complex surfaces of general type with $p_g=1$, $q=0$, and $K^2=1, 2$ using the same method.
Erhard Neher, Alistair Savage, Prasad Senesi
Suppose a finite group acts on a scheme X and a finite-dimensional Lie algebra g. The corresponding equivariant map algebra is the Lie algebra M of equivariant regular maps from X to g. We classify the irreducible finite-dimensional representations of these algebras. In particular, we show that all such representations are tensor products of evaluation repre
Beena Kalisky, John R. Kirtley, James G. Analytis, Jiun-Haw Chu
Superconducting quantum interference device (SQUID) microscopy shows stripes of increased diamagnetic susceptibility in underdoped, but not overdoped, single crystals of Ba(Fe1-xCox)2As2. These stripes of increased diamagnetic susceptibility are consistent with enhanced superfluid density on twin boundaries. Individual vortices avoid pinning on or crossing t
Serguei A. Mokhov, Joey Paquet, Mourad Debbabi
In this work we model the ACME (a fictitious company name) "printer case incident" and make its specification in Forensic Lucid, a Lucid- and intensional-logic-based programming language for cyberforensic analysis and event reconstruction specification. The printer case involves a dispute between two parties that was previously solved using the finit
A novel wear-resistant magnetic thin film material based on a $Ti_{1-x}Fe_xC_{1-y}$ nanocomposite alloy
cond-mat.mtrl-sciStojanka Bijelovic, Mikael Råsander, Ola Wilhelmsson, Erik Lewin
In this study we report on the film growth and characterization of thin (approximately 50 nm thick) Ti-Fe-C films deposited on amorphous quartz. The experimental studies have been complemented by first principles density functional theory (DFT) calculations. Upon annealing of as-prepared films, the composition of the metastable Ti-Fe-C film changes. An iron-
Three-dimensional evolution of magnetic and velocity shear driven instabilities in a compressible magnetized jet
physics.plasm-phLapo Bettarini, Simone Landi, Marco Velli, Pasquale Londrillo
The problem of three-dimensional combined magnetic and velocity shear driven instabilities of a compressible magnetized jet modeled with a plane neutral/current double vortex sheet in the framework of the resistive magnetohydrodynamics is addressed. The resulting dynamics given by the stream+current sheet interaction is analyzed and the effects of a variable
Lapo Bettarini, Giovanni Lapenta
This work presents a 2.5-dimensional simulation study of the instability of current-sheets located in a medium with a strong density variation along the current layer. The initial force-free configuration is observed to undergo a two-stage evolution consisting of an abrupt regime transition from a slow to a fast reconnection process leading the system to a f
Regularity and mass conservation for discrete coagulation-fragmentation equations with diffusion
math.APJosé A. Cañizo, Laurent Desvillettes, Klemens Fellner
We present a new a-priori estimate for discrete coagulation-fragmentation systems with size-dependent diffusion within a bounded, regular domain confined by homogeneous Neumann boundary conditions. Following from a duality argument, this a-priori estimate provides a global $L^2$ bound on the mass density and was previously used, for instance, in the context
R. Guandalini, M. Busso
The study of the evolutionary properties of Asymptotic Giant Branch stars still presents unresolved topics. Progress in the theoretical understanding of their evolution is hampered by the difficulty to empirically explain key physical parameters like their luminosity, mass loss rate and chemical abundances. We are performing an analysis of Galactic AGB stars
Arindam Kundagrami, M. Muthukumar
The charge of a polyelectrolyte (PE) controls myriads of phenomena in biology, biotechnology, and materials science, but still remains elusive from an understanding. Considering the adsorption of counterions on an isolated PE chain, an analytical expression for the effective charge - valid for all chain flexibility, for variable salt, in good solvents at all
Measurement of the Top Quark Mass Using the Invariant Mass of Lepton Pairs in Soft Muon b-tagged Events
hep-exThe CDF Collaboration, T. Aaltonen
We present the first measurement of the mass of the top quark in a sample of $t\bar{t}\to\ell\barν b\bar{b} q\bar{q}$ events (where $\ell = e$, $μ$) selected by identifying jets containing a muon candidate from the semileptonic decay of heavy-flavor hadrons (soft muon $b$-tagging). The $p\bar{p}$ collision data used corresponds to an integrated luminosity of
Duncan A. Forbes, Pavel Kroupa, Manuel Metz, Lee Spitler
Our Milky Way galaxy is host to a number of companions. These companions are gravitationally bound to the Milky Way and are stellar systems in their own right. They include a population of some 30 dwarf satellite galaxies (DSGs) and about 150 globular clusters (GCs). Here we discuss the relationship between GCs and DSGs using an interactive 3D model of the M
The Infrared Nuclear Emission of Seyfert Galaxies on Parsec Scales: Testing the Clumpy Torus models
astro-ph.COCristina Ramos Almeida, Nancy A. Levenson, Jose Miguel Rodriguez Espinosa, Almudena Alonso Herrero
We present subarcsecond resolution mid-infrared (mid-IR) photometry in the wavelength range from 8 to 20 micron of eighteen Seyfert galaxies, reporting high spatial resolution nuclear fluxes for the entire sample. We construct spectral energy distributions (SEDs) that the AGN dominates adding near-IR measurements from the literature at similar angular resolu
S. Kaufmann, U. K. Roessler, O. Heczko, M. Wuttig
Modulated phases occur in numerous functional materials like giant ferroelectrics and magnetic shape memory alloys. To understand the origin of these phases, we review and generalize the concept of adaptive martensite. As a starting point, we investigate the coexistence of austenite, adaptive 14M phase and tetragonal martensite in Ni-Mn-Ga magnetic shape mem
T. Ito, W. Bentz, I. C. Cloët, A. W. Thomas
A description of fragmentation functions which satisfy the momentum and isospin sum rules is presented in an effective quark theory. Concentrating on the pion fragmentation function, we first explain why the elementary (lowest order) fragmentation process q --> q πis completely inadequate to describe the empirical data, although the "crossed" process
The Disruption of Giant Molecular Clouds by Radiation Pressure and the Efficiency of Star Formation in Galaxies
astro-ph.GANorman Murray, Eliot Quataert, Todd A. Thompson
Star formation is slow, in the sense that the gas consumption time is much longer than the dynamical time. It is also inefficient; essentially all star formation in local galaxies takes place in giant molecular clouds (GMCs), but the fraction of a GMC converted to stars is very small, ~5%. In the most luminous starbursts, the GMC lifetime is shorter than the
Concentration and compactness in nonlinear Schrodinger-Poisson system with a general nonlinearity
math.APAntonio Azzollini
In this paper we use a concentration and compactness argument to prove the existence of a nontrivial nonradial solution to the nonlinear Schrodinger-Poisson equations in R3, assuming on the nonlinearity the general hypotheses introduced by Berestycki & Lions
Arne Rau, Shrinivas R. Kulkarni, Nicholas M. Law, Joshua S. Bloom
The Palomar Transient Factory (PTF) is a wide-field experiment designed to investigate the optical transient and variable sky on time scales from minutes to years. PTF uses the CFH12k mosaic camera, with a field of view of 7.9 deg^2 and a plate scale of 1 asec/pixel, mounted on the the Palomar Observatory 48-inch Samuel Oschin Telescope. The PTF operation st
Marco Baldi
The evidence in favor of a dark energy component dominating the Universe, and driving its presently accelerated expansion, has progressively grown during the last decade of cosmological observations. If this dark energy is given by a dynamic scalar field, it may also have a direct interaction with other matter fields in the Universe, in particular with cold
Oleg Y. Gnedin, Thomas J. Maccarone, Dimitrios Psaltis, Stephen E. Zepf
Large extra dimensions have been proposed as a possible solution to the hierarchy problem in physics. One of the suggested models, the RS2 braneworld model, makes a prediction that black holes evaporate by Hawking radiation on a short timescale that depends on the black hole mass and on the asymptotic radius of curvature of the extra dimensions. Thus the siz
P. Germain, N. Masmoudi, J. Shatah
We show existence of global solutions for the gravity water waves equation in dimension 3, in the case of small data. The proof combines energy estimates, which yield control of L^2 related norms, with dispersive estimates, which give decay in L^\infty. To obtain these dispersive estimates, we use an analysis in Fourier space; the study of space and time res
Michael J. Ramsey-Musolf
I discuss simple extensions of the Standard Model scalar sector that can help solve the origin of matter problem and that can be probed in their cosmologically relevant parameter space at the LHC.
The Coupling of a Wigner Polaronic Charge Density Wave with a Fermi Liquid Arising from the Instability of a Wigner Polaron Crystal: a Possible Pairing Mechanism in High Tc Superconductors
cond-mat.supr-conAntonio Bianconi, Mauro Missori
We report evidence that the metallic phase in high Tc cuprate superconductors results from an instability of the quasi 2D-electron gas at densities lower or larger than the critical density for the formation of a Wigner polaronic crystal. The electron gas undergoes a microscopic phase separation between 1) a polaron gas with density 1/8 at the Wigner localiz
Mohammad Edalati, Justin F. Vazquez-Poritz
We calculate the one-point function of certain chiral operators, known as open Wilson lines, in the holographic Nambu-Jona-Lasinio (NJL) model at finite temperature as well as finite chemical potential for quark (baryon) number density. These operators are holographically dual to Euclidean string worldsheets bounded by the flavor branes. Their one-point func
Jing Yang, Charles W. Wolgemuth, Greg Huber
\emph{Spiroplasma} swimming is studied with a simple model based on resistive-force theory. Specifically, we consider a bacterium shaped in the form of a helix that propagates traveling-wave distortions which flip the handedness of the helical cell body. We treat cell length, pitch angle, kink velocity, and distance between kinks as parameters and calculate
Emmanuel Clouet
We derive an expression of the core traction contribution to the dislocation elastic energy within linear anisotropic elasticity theory using the sextic formalism. With this contribution, the elastic energy is a state variable consistent with the work of the Peach-Koehler forces. This contribution needs also to be considered when extracting from atomic simul
Priyotosh Bandyopadhyay, Sandhya Choubey, Manimala Mitra
We propose a two Higgs doublet Type III seesaw model with $\mu$-$\tau$ flavor symmetry. We add an additional SU(2) Higgs doublet and three SU(2) fermion triplets in our model. The presence of two Higgs doublets allows for natural explanation of small neutrino masses with triplet fermions in the 100 GeV mass range, without fine tuning of the Yukawa couplings
M. Bustamante, A. M. Gago, C. Pena-Garay
We add an energy-independent Hamiltonian to the standard flavour oscillation one. This kind of physics might appear in theories where neutrinos couple differently to a plausible non-zero torsion of the gravitational field or more dramatically in the presence of CPT-violating physics in the flavour oscillations. If this contribution exists, experiments at hig
Roland M. Friedrich
In this article we develop a concise description of the global geometry which is underlying the universal construction of all possible generalised Stochastic Lœwner Evolutions. The main ingredient is the Universal Grassmannian of Sato-Segal-Wilson. We illustrate the situation in the case of univalent functions defined on the unit disc and the classical Schra
Effect of inhomogeneous surface relaxivity, pore geometry and internal field gradient on NMR logging:exact and perturbative theories and numerical investigations
cond-mat.otherSeungoh Ryu
Nuclear magnetic resonance is widely used as a probe of pore geometry and fluid composition in well logging. One of the critical assumptions often made is that the diffusion of fluid molecules is sufficiently fast to warrant the condition for direct mapping between the surface-enhanced relaxation rate and the pore geometry. In pores satisfying such a conditi
Nicholas Mastronarde, Mihaela van der Schaar
In our previous work, we proposed a systematic cross-layer framework for dynamic multimedia systems, which allows each layer to make autonomous and foresighted decisions that maximize the system's long-term performance, while meeting the application's real-time delay constraints. The proposed solution solved the cross-layer optimization offline, unde
Zygmunt Lalak
Gauge mediation of supersymmetry breakdown has many attractive features and can be realized in phenomenologically interesting string-motivated models. We point out that in models with the Polonyi-like field stabilized at a low expectation value by quantum corrections, gravity seems to limit from above the admixture of gravity mediation to the dominant gauge
Ioannis Kontoyiannis, Sean P. Meyn
We argue that the spectral theory of non-reversible Markov chains may often be more effectively cast within the framework of the naturally associated weighted-$L_\infty$ space $L_\infty^V$, instead of the usual Hilbert space $L_2=L_2(π)$, where $π$ is the invariant measure of the chain. This observation is, in part, based on the following results. A discrete
M. Kopp, H. Schomerus
Weyl's law approximates the number of states in a quantum system by partitioning the energetically accessible phase-space volume into Planck cells. Here we show that typical resonances in generic open quantum systems follow a modified, fractal Weyl law, even though their classical dynamics is not globally chaotic but also contains domains of regular motion.
Nonaxisymmetric Rossby Vortex Instability with Toroidal Magnetic Fields in Radially Structured Disks
astro-ph.SRCong Yu, Hui Li
We investigate the global nonaxisymmetric Rossby vortex instability in a differentially rotating, compressible magnetized accretion disk with radial density structures. Equilibrium magnetic fields are assumed to have only the toroidal component. Using linear theory analysis, we show that the density structure can be unstable to nonaxisymmetric modes. We find
Naseem Rangwala, T. B. Williams
We measure the Ca II 8542 line strength in 3360 stars along three lines-of-sight in the Galactic bar: (l,b) ~ (+/-5.0,-3.5) and Baade's Window, using Fabry-Perot (FP) absorption line spectroscopy. This is the first attempt to show that reliable absorption line strengths can be measured using FP spectroscopy. The Ca II 8542 line is a good indicator of met
Semiclassical Wigner distribution for two-mode entangled state generated by an optical parametric oscillator
quant-phK. Dechoum, M. D. Hahn, A. Z. Khoury, R. O. Vallejos
We derive the steady state solution of the Fokker-Planck equation that describes the dynamics of the nondegenerate optical parametric oscillator in the truncated Wigner representation of the density operator. The adiabatic limit of strong pump damping is assumed. This phase space image provides a clear view of the intracavity two-mode entangled state valid i
Ivan Agullo, Jose Navarro-Salas, Gonzalo J. Olmo, Leonard Parker
A disturbing aspect of Hawking's derivation of black hole radiance is the need to invoke extreme conditions for the quantum field that originates the emitted quanta. It is widely argued that the derivation requires the validity of the conventional relativistic field theory to arbitrarily high, trans-Planckian scales. We stress in this note that this is n
Stefan Hollands, Heiner Olbermann
In this paper, we explain how perturbative quantum field theory can be formulated in terms of (a version of) vertex algebras. Our starting point is the Wilson-Zimmermann operator product expansion (OPE). Following ideas of a previous paper [arXiv:0802.2198], we consider a consistency (essentially associativity) condition satisfied by the coefficients in this
Valerio Faraoni
We reply to a comment by Capozziello and Vignolo about the Cauchy problem of Palatini f(R) gravity.
Dominant mobility modulation by the electric field effect at the LaAlO_3 / SrTiO_3 interface
cond-mat.supr-conC. Bell, S. Harashima, Y. Kozuka, M. Kim
Caviglia et al. [Nature (London) 456, 624 (2008)] have found that the superconducting LaAlO_3 / SrTiO_3 interface can be gate modulated. A central issue is to determine the principal effect of the applied electric field. Using magnetotransport studies of a gated structure, we find that the mobility variation is almost five times as large as the sheet carrier
V. A. Petrov, R. A. Ryutin, A. E. Sobol
We propose an experiment at the LHC with leading neutron production.The latter can be used to extract from it the total $\pi^+ p$ cross-sections. With two leading neutrons we can get access to the total $\pi^+\pi^+$ cross-sections. In this note we give some estimates and discuss related problems and prospects.
J. I. Katz
This paper reviews and develops the proposal, widely discussed but not examined in detail, to use stratospheric aerosols to increase the Earth's albedo to Solar radiation in order to control climate change. The potential of this method has been demonstrated by the "natural experiments" of volcanic injection of sulfate aerosols into the stratosphe
Quintuple-layer epitaxy of high-quality Bi2Se3 thin films for topological insulator
cond-mat.mes-hallGuanhua Zhang, Huajun Qin, Jing Teng, Jiandong Guo
We report the growth of atomically smooth, single crystalline Bi2Se3 thin films on Si(111) by using molecular beam epitaxy. Scanning tunneling microscopy, low-energy electron diffraction, X-ray photoelectron emission spectroscopy and Raman spectroscopy were used to characterize the stoichiometry and crystallinity of the film. The film grows in a self-organiz
Chris Lintott, Kevin Schawinski, William Keel, Hanny van Arkel
We report the discovery of an unusual object near the spiral galaxy IC 2497, discovered by visual inspection of the Sloan Digital Sky Survey (SDSS) as part of the Galaxy Zoo project. The object, known as Hanny's Voorwerp, is bright in the SDSS g band due to unusually strong OIII 4959-5007 emission lines. We present the results of the first targeted obser
Inclusive single-particle production in two-photon collisions at LEP II with the DELPHI detector
hep-exThe DELPHI Collaboration, J. Abdallah
A study of the inclusive charged hadron production in two-photon collisions is described. The data were collected with the DELPHI detector at LEP II. Results on the inclusive single-particle p_T distribution and the differential charged hadrons dsigma/dp_T cross-section are presented and compared to the predictions of perturbative NLO QCD calculations and to
R. Fleischhaker, J. Evers
Light propagation in chiral media is discussed. We derive the wave equations for a probe pulse propagating through a chiral medium, and solve them analytically in Fourier space using the slowly varying envelope approximation. Our analysis reveals the influence of the different medium response coefficients on the propagation dynamics. Applying these results t
M. Rubio, S. Paron, G. Dubner
The 30 Doradus region in the Large Magellanic Cloud is one of the most outstanding star forming regions of the Local Group and a primary target to study star formation in an environment of low metallicity. In order to obtain a more complete picture of the not yet consumed or dispersed cool gas, we searched for line emission from molecular clouds that could b
H. Neuberger
The eigenvalues of Wilson loop matrices in SU(N) gauge theories in dimensions 2,3,4 at infinite N are supported on a small arc on the unit circle centered at $z=1$ for small loops, but expand to the entire unit circle for large loops. These two regimes are separated by a large N phase transition whose universal properties are the same in d=2,3 and 4. Hopeful
Andrea Scaramucci, Thomas A. Kaplan, Maxim Mostovoy
We study the structure of domain walls in multiferroic magnets with the conical spiral ordering. We formulate a simple spin model which has a conical spiral ground state in absence of magnetic anisotropies. We find a transition from the regime where ferromagnetic and ferroelectric domain walls are clamped to the regime where they are decoupled and derive a c