November 2007 arXiv papers — page 41

V. O. Nesterenko, W. Kleinig, J. Kvasil, P. Vesely

Time-odd densities and their effect on electric giant resonances are investigated within the self-consistent separable random-phase-approximation (SRPA) model for various Skyrme forces (SkT6, SkO, SkM*, SIII, SGII, SLy4, SLy6, SkI3). Time-odd densities restore Galilean invariance of the Skyrme functional, violated by the effective-mass and spin-orbital terms

Sharmila Goedhart, Michael J. Gaylard, D. Johan van der Walt

An intensive monitoring program of 54 6.7-GHz methanol maser sources was carried out at the Hartebeesthoek Radio Astronomy Observatory from January 1999 to April 2003. The monitoring program was subsequently continued on 19 sources of interest. Analysis of the resulting time-series stretching over eight years shows that six of the sources are periodic, with

Bernhard Krötz, Henrik Schlichtkrull

Let Y=G/H be a semisimple symmetric space. It is shown that the smooth vectors for the regular representation of G on L^p(Y) vanish at infinity.

S. Albino, B. A. Kniehl, G. Kramer

The standard analytic solution to the DGLAP equation in Mellin space is improved by resumming the large x divergences. Explicit results are given to next-to-leading order and next-to-leading logarithmic accuracy. Numerically, the theoretical error is found to be reduced by the resummation for a large range of x.

L. Angelani, G. Ruocco

The thermodynamics and topology of mean-field models with 2+k body interaction terms (generalizing XY model) are derived. Focusing on two particular cases (2+4 and 2+6 body interaction terms), a comparison between thermodynamic (phase transition energy, thermodynamically forbidden energy regions) and topological (singularity and curvature of saddle entropy)

Mathieu Bouville, Rajeev Ahluwalia

We use the phase-field method to study the martensitic transformation at the nanoscale. For nanosystems such as nanowires and nanograins embedded in a stiff matrix, the geometric constraints and boundary conditions have an impact on martensite formation, leading to new microstructures --such as dots aligned on a square lattice with axes along <01>-- or preve

C. J. Conselice, K. Bundy, Vivian U, P. Eisenhardt

We present in this paper an analysis of the faint and red near-infrared selected galaxy population found in near-infrared imaging from the Palomar Observatory Wide-Field Infrared Survey. This survey covers 1.53 deg^2 to 5-sigma detection limits of K_vega = 20.5-21 and J_vega = 22.5, and overlaps with the DEEP2 spectroscopic redshift survey. We discuss the de

Émilien Azema, Farhang Radjaï, Robert Peyroux, Vincent Richefeu

We analyze the dynamics of a 3D granular packing composed of particles of irregular polyhedral shape confined inside a rectangular box with a retaining wall sub jected to horizontal harmonic forcing. The simulations are performed by means of the contact dynamics method for a broad set of loading parameters. We explore the vibrational dynamics of the packing,

S L Bud&#39;ko, S A Law, P C Canfield, G D Samolyuk

Data on temperature-dependent, anisotropic thermal expansion in pure and doped RAgSb2 (R = Y, Sm, La) single crystals are presented. Using the Ehrenfest relation and heat capacity measurements, uniaxial pressure derivatives for long range magnetic ordering and charge density wave transition temperatures are evaluated and compared with the results of the dire

G. G. Kiss, Gy. Gyurky, Z. Elekes, Zs. Fulop

The cross sections of the 70Ge(p,gamma)71As and 76Ge(p,n)76As reactions have been measured with the activation method in the Gamow window for the astrophysical p process. The experiments were carried out at the Van de Graaff and cyclotron accelerators of ATOMKI. The cross sections have been derived by measuring the decay gamma-radiation of the reaction produ

G. Alecian, M. J. Stift

In recent papers convincing evidence has been presented for chemical stratification in Ap star atmospheres, and surface abundance maps have been shown to correlate with the magnetic field direction. Radiatively driven diffusion in magnetic fields is among the processes responsible for these inhomogeneities. Here we explore the hypothesis that equilibrium str

Andreas Jansson, Olga Mena, Stephen Parke, Niki Saoulidou

We explore an alternative strategy to determine the neutrino mass hierarchy by making use of possible future neutrino facilities at Fermilab. Here, we use CPT-conjugate neutrino channels, exploiting a nu_mu beam from the NuMI beamline and a barnu_e beam from a betabeam experimental setup. Both experiments are performed at approximately the same E/L. We prese

W. Dahmen, T. Rohwedder, R. Schneider, A. Zeiser

This paper is concerned with the design and analysis of a fully adaptive eigenvalue solver for linear symmetric operators. After transforming the original problem into an equivalent one formulated on $\ell_2$, the space of square summable sequences, the problem becomes sufficiently well conditioned so that a gradient type iteration can be shown to reduce the

Roberto De Leo, Sergio Demelio

We present the results of our numerical analysis of a &#34;composite&#34; model of DNA which generalizes a well-known elementary torsional model of Yakushevich by allowing bases to move independently from the backbone. The model shares with the Yakushevich model many features and results but it represents an improvement from both the conceptual and the pheno

Lorenzo Zambotti

We consider the problem of conditioning the Brownian excursion to have a fixed time average over the interval [0,1] and we study an associated stochastic partial differential equation with reflection at 0 and with the constraint of conservation of the space average. The equation is driven by the derivative in space of a space-time white noise and contains a

Shinya Katayama, Akito Kobayashi, Yoshikazu Suzumura

We investigate the formation of density waves in the zero-gap state (ZGS) which has been found in the quasi-two-dimensional organic conductor $α$-(BEDT-TTF)$_2$I$_3$ salt under the hydrostatic pressure. The ZGS exhibits the cone-like dispersion for both the conduction band and the valence band which degenerate each other at the two-dimensional wave vectors,

German Sierra

We discuss a possible spectral realization of the Riemann zeros based on the Hamiltonian $H = xp$ perturbed by a term that depends on two potentials, which are related to the Berry-Keating semiclassical constraints. We find perturbatively the potentials whose Jost function is given by the zeta function $ζ(σ- i t)$ for $σ> 1$. For $σ= 1/2$ we find the potenti

Jacob Linder, Asle Sudbø

We study the proximity-induced superconducting correlations as well as the local density of states of a ferromagnet, in a ferromagnet/s-wave superconductor heterostructure. We include the effects of spin-flip scattering, non-ideal interfaces, and the presence of impurities in the sample. We employ the quasiclassical theory of superconductivity, solving the U

Soonsik Kwon

We consider the initial value problem of the fifth order modified KdV equation on the Sobolev spaces. \partial_t u - \partial_x^5u + c_1\partial_x^3(u^3) + c_2u\partial_x u\partial_x^2 u + c_3uu\partial_x^3 u =0, u(x,0)= u_0(x) where $ u:R\timesR \to R $ and $c_j$&#39;s are real. We show the local well-posedness in H^s(R) for s \geq 3/4 via the contraction p

M. Kohno, R. Okamoto, H. Kamada, Y. Fujiwara

Equivalent interactions in a low-momentum space for the $ΛN$, $ΣN$ and $ΞN$ interactions are calculated, using the SU$_6$ quark model potential as well as the Nijmegen OBEP model as the input bare interaction. Because the two-body scattering data has not been accumulated sufficiently to determine the hyperon-nucleon interactions unambiguously, the constructi

Soma Nath, Ujjal Debnath, Subenoy Chakraborty

In this work the junction conditions between the exterior Reissner-Nordstrom-Vaidya space-time with the interior quasi-spherical Szekeres space-time have been studied for analyzing gravitational collapse in the presence of a magneto-hydrodynamic fluid undergoing dissipation in the form of heat flow. We have discussed about the apparent horizon and have evalu

Igal Sason, Gil Wiechman

This paper provides simple lower bounds on the number of iterations which is required for successful message-passing decoding of some important families of graph-based code ensembles (including low-density parity-check codes and variations of repeat-accumulate codes). The transmission of the code ensembles is assumed to take place over a binary erasure chann

Daniel Andersson, Kristoffer Arnsfelt Hansen, Peter Bro Miltersen, Troels Bjerre Sorensen

We define the class of &#34;simple recursive games&#34;. A simple recursive game is defined as a simple stochastic game (a notion due to Anne Condon), except that we allow arbitrary real payoffs but disallow moves of chance. We study the complexity of solving simple recursive games and obtain an almost-linear time comparison-based algorithm for computing an

Peter J. Mosley, Jeff S. Lundeen, Brian J. Smith, Piotr Wasylczyk

We present an experimental demonstration of heralded single photons prepared in pure quantum states from a parametric downconversion source. It is shown that, through controlling the modal structure of the photon pair emission, one can generate pairs in factorable states and thence eliminate the need for spectral filters in multiple-source interference schem

Shoji Yamamoto, Jun Ohara

Motivated by the homometallic intertwining double-chain ferrimagnets A_3_Cu_3_(PO_4_)_4_ (A=Ca,Sr,Pb), we investigate the low-energy structure of their model Hamiltonian H=\sum_n_[J_1_(S_{n :1}_+S_{n :3}_) +J_2_(S_{n+1:1}+S_{n-1:3}_)]\cdotS_{n:2}_, where S_{n:l}_ stands for the Cu^{2+}^ ion spin labeled l in the nth trimer unit, with particular emphasis on t

R. A. García, J. Ballot

It is usual in helioseismology to remove unwanted instrumental low-frequency trends by applying high-pass filters to the time series. However, the choice of the filter is very important because it can keep the periodic signals throughout the spectrum. At the same time, these filters should not introduce any spurious effects on the remaining signal, which wou

J. Lopez-Pavon

Some theories of new physics accounting for neutrino masses can give rise to a low-energy non-unitary leptonic mixing matrix. It is shown that the CP-asymmetries in the $ν_μ\to ν_τ$ channel are an excellent probe of such new physics. In adition, we clarify the relationship betweeen our framework and the so called &#34;non-standard neutrino interactions&#34;

K. V. P. Latha, Dilip Angom, Rajat K. Chaudhuri, B. P. Das

The effects of parity and time reversal violating potential, in particular the tensor-pseudotensor electron nucleus interaction are studied. We establish that selected terms representing the interplay of these effects and the residual Coulomb interaction in the coupled-cluster method are equivalent to the coupled perturbed Hartree-Fock. We have shown that th

B. Fuchs, O. Esquivel

Recent high-resolution simulations together with theoretical studies of the dynamical evolution of galactic disks have shown that contrary to wide-held beliefs a `live&#39;, dynamically responsive, dark halo surrounding a disk does not stabilize the disk against dynamical instabilities. We generalize Toomre&#39;s Q stability parameter for a disk-halo system

M. Demianski, E. Piedipalumbo, C. Rubano, P. Scudellaro

We consider cosmological models in scalar tensor theories of gravity that describe an accelerating universe, and we study a family of inverse power law potentials, for which exact solutions of the Einstein equations are known. We also compare theoretical predictions of our models with observations. For this we use the following data: the publicly available c

William J. Ugalde

We review previous work of Alain Connes, and its extension by the author, on some conformal invariants obtained from the noncommutative residue on even dimensional compact manifolds without boundary. Inspired by recent work of Yong Wang, we also address possible generalizations of these conformal invariants to the setting of compact manifolds with boundary.

Hervé Kunz, Boris Shapiro

We study the average density of resonances (DOR) for a semi-infinite disordered chain, coupled to the outside world by a (semi-infinite) perfect lead. A set of equations is derived, which provides the general framework for calculating the average DOR, for an arbitrary disorder and coupling strength. These general equations are applied to the case of weak cou

Ghazi Bouselmi, Dominique Fohr, Irina Illina, Jean-Paul Haton

In this article, we present an approach for non native automatic speech recognition (ASR). We propose two methods to adapt existing ASR systems to the non-native accents. The first method is based on the modification of acoustic models through integration of acoustic models from the mother tong. The phonemes of the target language are pronounced in a similar

Armen Nersessian

We discuss the generalizations of the MICZ-Kepler system (the system describing the motion of the charged particle in the field of Dirac dyon), to the curved spaces, arbitrary potentials and to the multi-dyon background.

Armen Nersessian, Vahagn Yeghikyan

We present the higher-dimensional generalization of anisotropic (pseudo)spherical oscillator suggested recently in [arXiv:0710.5001], and the related spherical and pseudosperical generalizations (MICZ-)Kepler like systems with Stark term and $\cosθ$ potential. We write down the potentials and hidden symmetry generators of these systems, in terms of ambient E

Agapitos Hatzinikitas

In this work we provide a novel approach for computing the coefficients of the characteristic polynomial of a square matrix. We demonstrate that each coefficient can be efficiently represented by a set of circle graphs. Thus, one can employ a diagrammatic approach to determine the coefficients of the characteristic polynomial.

Thorsten Renk

The nuclear suppression of high transverse momentum P_T hadrons is one of the most striking findings in heavy-ion collision experiments. It has long been recognized that the suppression can be theoretically described by folding the primary parton spectrum with an energy loss probability distribution which is suitably averaged over the collision geometry. How

M. Zhang, H. X. Zhang, Z. Y. Zhang

The possibility of $QQ\bar{q}\bar{q}$ heavy-light four-quark bound states has been analyzed by means of the chiral SU(3) quark model, where $Q$ is the heavy quark ($c$ or $b$) and $q$ is the light quark ($u$, $d$ or $s$). We obtain a bound state for the $bb\bar{n}\bar{n}$ configuration with quantum number $J^{P}=1^{+},I=0$ and for the $cc\bar{n}\bar{n}$ ($J^

M. Pulupa, S. D. Bale

We present \emph{in situ} observations of the source regions of interplanetary (IP) type II radio bursts, using data from the Wind spacecraft during the period 1996-2002. We show the results of this survey as well as in-depth analysis of several individual events. Each event analyzed in detail is associated with an interplanetary coronal mass ejection (ICME)

Susumu Inoue, Guenter Sigl, Francesco Miniati, Eric Armengaud

Large-scale accretion shocks around massive clusters of galaxies, generically expected in hierarchical scenarios of cosmological structure formation, are shown to be potential sources of the observed ultrahigh energy cosmic rays (UHECRs) by accelerating a mixture of heavy nuclei including the iron group elements. Current observations can be explained if the

C. Martin Gaskell, Elizabeth S. Klimek, Ludmila S. Nazarova

We consider in detail the spectral energy distribution (SED) and multi-wavelength variability of NGC5548. Comparison with the SEDs of other AGNs implies that the internal reddening of NGC5548 is E(B-V) = 0.17 mag. The extinction curve is consistent with the mean curve of other AGNs found by Gaskell & Benker, but inconsistent with an SMC-type reddening curve.

Guillaume Jourdan, Gauthier Torricelli, Joël Chevrier, Fabio Comin

Fabrication of Nano-Electro-Mechanical-Systems (NEMS) of high quality is nowadays extremely efficient. These NEMS will be used as sensors and actuators in integrated systems. Their use however raises questions about their interface (actuation, detection, read out) with external detection and control systems. Their operation implies many fundamental questions

Hiroshi Tamaru

In this paper, we study the solvmanifolds constructed from any parabolic subalgebras of any semisimple Lie algebras. These solvmanifolds are naturally homogeneous submanifolds of symmetric spaces of noncompact type. We show that the Ricci curvatures of our solvmanifolds coincide with the restrictions of the Ricci curvatures of the ambient symmetric spaces. C

Toshifumi Itakura

In recent years, researchers have discovered various excited states of electrons having an excited domain with a structural order different from the original one. We examine a dynamics of electron system and phonon system by using the time-dependent Hartree-Fock approximation. We examine time evolution with spin degree of freedom. We found a thermally excite

S. K. Pandey, Swapnil Patil, V. R. R. Medicherla, R. S. Singh

We investigate the detailed electronic structure of PrCoO$_3$ and its temperature evolution using state-of-the-art photoemission spectroscopy and ab initio band structure calculations. We observe that in addition to the correlation effect, spin-orbit interaction plays an important role in determining the electronic properties of this system. Pr 4$f$ states a

Shangduan Wu, Lei Jing, Qunxiang Li, Q. W. Shi

In this paper, the average density of states (ADOS) with a binary alloy disorder in disordered graphene systems are calculated based on the recursion method. We observe an obvious resonant peak caused by interactions with surrounding impurities and an anti-resonance dip in ADOS curves near the Dirac point. We also find that the resonance energy (Er) and the

Asterios Pantokratoras

Comment on Effects of transverse magnetic field on mixed convection in wall plume of power-law fluids, by Rama Subba Reddy Gorla, Jin Kook Lee, Shoichiro Nakamura and Ioan Pop [International Journal of Engineering Science, 31 (1993) 1035-1045]. In the above paper the authors treat the boundary layer mixed convection flow of a power-law fluid along a vertical

Collin Bleak, Bronlyn Wassink

The authors classify the finite index subgroups of R. Thompson&#39;s group $F$. All such groups that are not isomorphic to $F$ are non-split extensions of finite cyclic groups by $F$. The classification describes precisely which finite index subgroups of $F$ are isomorphic to $F$, and also separates the isomorphism classes of the finite index subgroups of $F

C. Martin Gaskell, A. J. Benker

We present intrinsic extinction curves for 14 AGNs. The AGNs have reddenings, E(B-V), of up to 0.36 mag. The majority (13 out of 14) of the extinction curves are not steep in the UV. Of the seven best determined extinction curves, five have extinction curves that are as flat as the standard Galactic curve in the optical and near UV, but flatter in the far UV

Akira R. Kinjo, Haruki Nakamura

A method to search for local structural similarities in proteins at atomic resolution is presented. It is demonstrated that a huge amount of structural data can be handled within a reasonable CPU time by using a conventional relational database management system with appropriate indexing of geometric data. This method, which we call geometric indexing, can e

Akira R. Kinjo, Haruki Nakamura

Position-specific scoring matrices (PSSMs) are useful for detecting weak homology in protein sequence analysis, and they are thought to contain some essential signatures of the protein families. In order to elucidate what kind of ingredients constitute such family-specific signatures, we apply singular value decomposition to a set of PSSMs and examine the pr

Achim Kempf

High temperature superconductors have in common that they consist of parallel planes of copper oxide separated by layers whose composition can vary. Being ceramics, the cuprate superconductors are poor conductors above the transition temperature, T_c. Below T_c, the parallel Cu-O planes in those materials become superconducting while the layers in between st

Gustavo Osorio, Mario di Bernardo, Stefania Santini

This paper is concerned with the analysis of a class of impacting systems of relevance in applications: cam-follower systems. We show that these systems, which can be modelled as discontinuously forced impact oscillators, can exhibit complex behaviour due to the detachment at high rotational speeds between the follower and the cam. We propose that the observ

Hua-Xing Chen, Atsushi Hosaka, Shi-Lin Zhu

We study the light scalar mesons in the QCD sum rule. We find that there are five independent scalar tetraquark currents in the local form, and we perform QCD sum rule analysis using both these currents and their combinations. Compared with the sum rules by conventional \bar{q} q currents, our result supports a tetraquark structure for low-lying scalar meson

Z. H. Qiao, J. Wang, Y. D. Wei, H. Guo

We report a theoretical investigation of quantized spin-Hall conductance fluctuation of graphene devices in the diffusive regime. Two graphene models that exhibit quantized spin-Hall effect (QSHE) are analyzed. Model-I is with unitary symmetry under an external magnetic field $B\ne 0$ but with zero spin-orbit interaction, $t_{SO}=0$. Model-II is with symplec

J. Ponce de Leon

It is well known that, in the five-dimensional scenario of braneworld and space-time-mass theories, geodesic motion in 5D is observed to be non-geodesic in 4D. Usually, the discussion is purely geometric and based on the dimensional reduction of the geodesic equation in 5D, without any reference to the test particle whatsoever. In this work we obtain the equ

Patrick Slane

The synchrotron-emitting nebulae formed by energetic winds from young pulsars provide information on a wide range phenomena that contribute to their structure. High resolution X-ray observations reveal jets and toroidal structures in many systems, along with knot-like structures whose emission is observed to be time-variable. Large-scale filaments seen in op

Y. H. Ahn, Sin Kyu Kang, C. S. Kim, Jake Lee

We investigate how the baryon asymmetry of our universe via leptogenesis can be achieved within the framework of the seesaw model with Fritzsch type lepton mass matrices proposed by Fukugita $et. al$. We study the cases with CP-violating phases in charged lepton Yukawa matrix, however, with and without Dirac neutrino Yukawa phases. We consider both flavor in

J. K. Freericks

Dynamical mean-field theory is generalized to solve the nonequilibrium Keldysh boundary problem: a system is started in equilibrium at a temperature T=0.1, a uniform electric field is turned on at t=0, and the system is monitored as it approaches the steady state. The focus here is on the Bloch oscillations of the current and how they decay after their initi

J. Ponce de Leon

A striking characteristic of non-Schwarzschild vacuum exteriors is that they contain not only the total gravitational mass of the source, but also an {\it arbitrary} constant. In this work, we show that the constants appearing in the &#34;temporal Schwarzschild&#34;, &#34;spatial Schwarzschild&#34; and &#34;Reissner-Nordstr{ö}m-like&#34; exteriors are not ar

Robert N. Proctor, Duncan A. Forbes, Jean P. Brodie, Jay Strader

We analyse Keck spectra of 24 candidate globular clusters (GCs) associated with the spiral galaxy NGC 2683. We identify 19 bona fide GCs based on their recession velocities, of which 15 were suitable for stellar population analysis. Age and metallicity determinations reveal old ages in 14 out of 15 GCs. These old GCs exhibit age and metallicity distributions

Kouji Nakamura

As in the case of the other gauge field theories, there is so called ``gauge&#39;&#39; also in general relativity. This ``gauge&#39;&#39; is unphysical degree of freedom. There are two kinds of ``gauges&#39;&#39; in general relativity. These are called the first- and the second-kind of gauges, respectively. The gauge of the first kind is just coordinate syst

Paul Kabaila, Khageswor Giri

We consider a linear regression model, with the parameter of interest a specified linear combination of the regression parameter vector. We suppose that, as a first step, a data-based model selection (e.g. by preliminary hypothesis tests or minimizing AIC) is used to select a model. It is common statistical practice to then construct a confidence interval fo

Pat Scott, Joakim Edsjö, Malcolm Fairbairn

Recent work has indicated that WIMP annihilation in stellar cores has the potential to contribute significantly to a star&#39;s total energy production. We report on progress in simulating the effects of WIMP capture and annihilation upon stellar structure and evolution near supermassive black holes, using the new DarkStars code. Preliminary results indicate

M. P. Muno, B. M. Gaensler, A. Nechita, J. M. Miller

We present constraints on the number of Galactic magnetars, which we have established by searching for sources with periodic variability in 506 archival Chandra observations and 441 archival XMM-Newton observations of the Galactic plane (|b|<5 degree). Our search revealed four sources with periodic variability on time scales of 200-5000 s, all of which are p

Leonid, Kontorovich

The rate at which dependencies between future and past observations decay in a random process may be quantified in terms of mixing coefficients. The latter in turn appear in strong laws of large numbers and concentration of measure results for dependent random variables. Questions regarding what rates are possible for various notions of mixing have been pose

Jan Rak

Measurements of the nuclear modification factor of inclusive yields of $π^0$, $p\bar{p}$, non-phtonic electrons and prompt photon measured at RHIC are reviewed. Some of the difficulties arising from interpretation of these measurements such as similarity of the suppression pattern of light and heavy quarks, quarks and gluons, light quarks and prompt photon a

Peter Imkeller, Ilya Pavlyukevich, Torsten Wetzel

We consider a dynamical system described by the differential equation $\dot{Y}_t=-U&#39;(Y_t)$ with a unique stable point at the origin. We perturb the system by the Lévy noise of intensity $\varepsilon$ to obtain the stochastic differential equation $dX^{\varepsilon}_t=-U&#39;(X^{\varepsilon}_{t-}) dt+\varepsilon dL_t.$ The process $L$ is a symmetric Lévy p

Leonid Malyshkin, Stanislav Boldyrev

We investigate magnetic field amplification in a turbulent velocity field with nonzero helicity, in the framework of the kinematic Kazantsev-Kraichnan model. We present the numerical solution of the model for the practically important case of Kolmogorov distribution of velocity fluctuations, with a large magnetic Reynolds number. We find that in contrast to

Gerald A. Miller, E. Piasetzky, G. Ron

We study the ratio $R\equivμG_E(Q^2)/G_M(Q^2)$ of the proton at very small values of $Q^2$. Radii commonly associated with these form factors are not moments of charge or magnetization densities. We show that the form factor $F_2$ is correctly interpretable as the two-dimensional Fourier transformation of a magnetization density. A relationship between the m

C. N. Varney, V. G. Rousseau, R. T. Scalettar

The study of ultracold optically trapped atoms has opened new vistas in the physics of correlated quantum systems. Much attention has now turned to mixtures of bosonic and fermionic atoms. A central puzzle is the disagreement between the experimental observation of a reduced bosonic visibility ${\cal V}_b$, and quantum Monte Carlo (QMC) calculations which sh

E. H. Hwang, S. Das Sarma

We theoretically calculate the phonon scattering limited electron mobility in extrinsic (i.e. gated or doped with a tunable and finite carrier density) 2D graphene layers as a function of temperature $(T)$ and carrier density $(n)$. We find a temperature dependent phonon-limited resistivity $ρ_{ph}(T)$ to be linear in temperature for $T\agt 50 K$ with the ro

Patrick Brosnan, Hao Fang, Zhaohu Nie, Gregory Pearlstein

In a recent paper, M. Green and P. Griffiths used R. Thomas&#39; works on nodal hypersurfaces to establish the equivalence of the Hodge conjecture and the existence of certain singular admissible normal functions. Inspired by their work, we study normal functions using M. Saito&#39;s mixed Hodge modules and prove that the existence of singularities of the ty

Thomas Chen, Itaru Sasaki

We discuss some basic aspects of the dynamics of a homogenous Fermi gas in a weak random potential, under negligence of the particle pair interactions. We derive the kinetic scaling limit for the momentum distribution function with a translation invariant initial state and prove that it is determined by a linear Boltzmann equation. Moreover, we prove that if

Ugo Aglietti, Francesca Di Lodovico, Giancarlo Ferrera, Giulia Ricciardi

By analyzing B -> X_u l nu_l spectra with a model based on soft-gluon resummation and an analytic time-like QCD coupling, we obtain |V_ub| = (3.76 +-0.13 +- 0.22)*10^(-3), where the first and the second error refers to experimental and theoretical errors, respectively. The V_ub value is obtained from the available measured semileptonic branching fractions in

Lior M. Burko, Gaurav Khanna

The decay rate of late time tails in the Kerr spacetime have been the cause of numerous conflicting results, both analytical and numerical. In particular, there is much disagreement on whether the decay rate of an initially pure multipole moment ${\ell}$ is according to $t^{-(2{\bar\ell}+3)}$, where ${\bar\ell}$ is the least multipole moment whose excitation

Zhe Xu, Carsten Greiner, Horst Stoecker

The elliptic flow $v_2$ and the ratio of the shear viscosity over the entropy density, $η/s$, of gluon matter are calculated from the perturbative QCD (pQCD) based parton cascade Boltzmann approach of multiparton scatterings. For Au+Au collisions at $\sqrt{s}=200$A GeV the gluon plasma generates large $v_2$ values measured at the BNL Relativistic Heavy Ion C

Anaelle Halle, HongSheng Zhao, Baojiu Li

We propose a unified single-field description of the galactic Dark Matter and various uniform scalar fields for the inflation and cosmological constant. The two types of effects could originate from a fluid of both spatially and temporally varying Vacuum Energy if the vacuum has an uneven pressure caused by a photon-like vector field (of perhaps an unstable

T. Mansson

We investigate higher loop integrability for a q-deformation of the su(2)-sector of N=4 SYM theory. First we construct a generalisation of the long range spin chain, which for the lowest orders describes the non-deformed dilatation operator. This generalised model is built up from Temperley-Lieb algebra generators and describes the deformed theory to at leas

G. C. Levine, D. J. Miller

The entanglement entropy of a gapless fermion subsystem coupled to a gapless bulk by a &#34;weak link&#34; is considered. It is demonstrated numerically that each independent weak link contributes an entropy proportional to lnL, where L is linear dimension of the subsystem.

R. N. Mohapatra, Nobuchika Okada, Hai-Bo Yu

Anomaly mediated supersymmetry breaking (AMSB), when implemented in MSSM is known to suffer from the problem of negative slepton mass squared leading to breakdown of electric charge conservation. We show however that when MSSM is extended to explain small neutrino masses by including a pair of superheavy Higgs triplet superfields (the type II seesaw mechanis

Jonathan Bagger, Neil Lambert

In previous work we proposed a field theory model for multiple M2-branes based on an algebra with a totally antisymmetric triple product. In this paper we gauge a symmetry that arises from the algebra&#39;s triple product. We then construct a supersymmetric theory that is consistent with all the symmetries expected of a multiple M2-brane theory: 16 supersymm

Dominique Spehner, Fritz Haake

We study a class of quantum measurement models. A microscopic object is entangled with a macroscopic pointer such that each eigenvalue of the measured object observable is tied up with a specific pointer deflection. Different pointer positions mutually decohere under the influence of a bath. Object-pointer entanglement and decoherence of distinct pointer rea

Hannah Markwig, Josephine Yu

The space T_{d,n} of n tropically collinear points in a fixed tropical projective space TP^{d-1} is equivalent to the tropicalization of the determinantal variety of matrices of rank at most 2, which consists of real d x n matrices of tropical or Kapranov rank at most 2, modulo projective equivalence of columns. We show that it is equal to the image of the m

Pierre Darancet, Nicolas Wipf, Claire Berger, Walt de Heer

We propose a mechanism for the quenching of the Shubnikov de Haas oscillations and the quantum Hall effect observed in epitaxial graphene. Experimental data show that the scattering time of the conduction electron is magnetic field dependent and of the order of the cyclotron orbit period, \textit{i.e.} can be much smaller than the zero field scattering time.

Olivier Lopez, Anne Amy-Klein, Christophe Daussy, Christian Chardonnet

RF frequency transfer over an urban 86 km fibre has been demonstrated with a resolution of 2.10-18 at one day measuring time using an optical compensator. This result is obtained with a reference carrier frequency of 1 GHz, and a rapid scrambling of the polarisation state of the input light in order to reduce the sensitivity to the polarisation mode dispersi

J. Lember, A. Koloydenko

Since the early days of digital communication, Hidden Markov Models (HMMs) have now been routinely used in speech recognition, processing of natural languages, images, and in bioinformatics. An HMM $(X_i,Y_i)_{i\ge 1}$ assumes observations $X_1,X_2,...$ to be conditionally independent given an &#34;explanotary&#34; Markov process $Y_1,Y_2,...$, which itself

Oliver J. Rosten

It is pointed out that the exact renormalization group approach to cosmological perturbation theory, proposed in Matarrese and Pietroni, JCAP 0706 (2007) 026, arXiv:astro-ph/0703563 and arXiv:astro-ph/0702653, constitutes a misnomer. Rather, having instructively cast this classical problem into path integral form, the evolution equation then derived comes ab

Huirong Yan, A. Lazarian

We continue our studies of atomic alignment in diffuse media, in particularly, in interstellar and circumstellar media, with the goal of developing new diagnostics of magnetic fields in these environments. We understand atomic alignment as alignment of atoms or ions in their ground state. Such atoms are sensitive to weak magnetic fields. In particular, we pr

Paulo C. C. Freire, Scott M. Ransom, Steve Begin, Ingrid H. Stairs

Motivated by the recent discovery of 30 new millisecond pulsars in Terzan 5, made using the Green Bank Telescope&#39;s S-band receiver and the Pulsar Spigot spectrometer, we have set out to use the same observing system in a systematic search for pulsars in other globular clusters. Here we report on the discovery of five new pulsars in NGC 6440 and three in

Florian Bauer, Lily Schrempp

We establish an indirect link between relic neutrinos and the dark energy sector which originates from the vacuum energy contributions of the neutrino quantum fields. Via renormalization group effects they induce a running of the cosmological constant with time which dynamically influences the evolution of the cosmic neutrino background. We demonstrate that

Remco Duits, Erik Franken

We provide the explicit solutions of linear, left-invariant, (convection)-diffusion equations and the corresponding resolvent equations on the 2D-Euclidean motion group SE(2). These diffusion equations are forward Kolmogorov equations for stochastic processes for contour enhancement and completion. The solutions are group-convolutions with the corresponding

Giovanni Volpe, Jan Wehr, Dmitri Petrov, J. Miguel Rubi

In order to stabilize the behavior of noisy systems, confining it around a desirable state, an effort is required to suppress the intrinsic noise. This noise suppression task entails a cost. For the important case of thermal noise in an overdamped system, we show that the minimum cost is achieved when the system control parameters are held constant: any addi

José Burillo, Sean Cleary, Claas E. Röver

We determine the abstract commensurator com(F) of Thompson&#39;s group F and describe it in terms of piecewise linear homeomorphisms of the real line and in terms of tree pair diagrams. We show com (F) is not finitely generated and determine which subgroups of finite index in F are isomorphic to F. We show that the natural map from the commensurator group to

Pedro Ojeda, Aurora Londono, Nan-Yow Chen, Martin Garcia

We present a theoretical study of the folding of small proteins inside confining potentials. Proteins are described in the framework of an effective potential model which contains the Ramachandran angles as degrees of freedom and does not need any {\it a priori} information about the native state. Hydrogen bonds, dipole-dipole- and hydrophobic interactions a

V. V. Bavula

Two theorems of J. F. Ritt on decompositions of polynomials maps are generalized to a more general situation: for, so-called, reduction monoids ($(K[x], \circ)$ and $(K[x^2]x, \circ)$ are examples of reduction monoids). In particular, analogues of the two theorems of J. F. Ritt hold for the monoid $(K[x^2]x, \circ)$ of odd polynomials. It is shown that, in g

Fay Dowker, Yousef Ghazi-Tabatabai

The Kochen-Specker Theorem is widely interpreted to imply that non-contextual hidden variable theories that agree with the predictions of Copenhagen quantum mechanics are impossible. The import of the theorem for a novel observer independent interpretation of quantum mechanics, due to Sorkin, is investigated.

Liang Gao, Julio F. Navarro, Shaun Cole, Carlos Frenk

(Abridged) We use two very large cosmological simulations to study how the density profiles of relaxed LCDM dark halos depend on redshift and on halo mass. We confirm that these profiles deviate slightly but systematically from the NFW form and are better approximated by the empirical formula, $d\log ρ/d\log r \propto r^α$, first used by Einasto to fit star

A. De Rujula

I review the subjects of non-solar cosmic rays (CRs) and long-duration gamma-ray bursts (GRBs). Of the various interpretations of these phenomena, the one best supported by the data is the following. Accreting compact objects, such as black holes, are seen to emit relativistic puffs of plasma: `cannonballs&#39; (CBs). The inner domain of a rotating star whos

S. Staudenmayer, W. Belzig, C. Bruder

We discuss the occupation number correlations in an ultracold system of interacting fermionic atoms. For a system with a special energy-level distribution, viz. two multiply-degenerate levels, explicit expressions for the correlation functions are derived in a canonical approach using the exact ground state wavefunction of the reduced BCS Hamiltonian. We eva