April 2009 arXiv papers — page 13

William H. Lee, Enrico Ramirez-Ruiz, Diego Lopez-Camara

We consider the long term evolution of debris following the tidal disruption of compact stars in the context of short gamma ray bursts (SGRBs). The initial encounter impulsively creates a hot, dense, neutrino-cooled disk capable of powering the prompt emission. After a long delay, we find that powerful winds are launched from the surface of the disk, driven

Brian D. Smithling

Local models are schemes, defined in terms of linear algebra, that were introduced by Rapoport and Zink to study the étale-local structure of integral models of certain PEL Shimura varieties over p-adic fields. A basic requirement for the integral models, or equivalently for the local models, is that they be flat. In the case of local models for even orthogo

Ian Shipman

We study the structural and homological properties of graded Artinian modules over generalized Weyl algebras (GWAs), and this leads to a decomposition result for the category of graded Artinian modules. Then we define and examine a category of graded modules analogous to the BGG category O. We discover a condition on the data defining the GWA that ensures O

Leo Radzihovsky, Sungsoo Choi

We show that a degenerate gas of two-species bosonic atoms interacting through a p-wave Feshbach resonance (as realized in, e.g., a 85Rb-87Rb mixture) exhibits a finite-momentum atomic-molecular superfluid (AMSF), sandwiched by a molecular p-wave (orbital spinor) superfluid and by an s-wave atomic superfluid at large negative and positive detunings, respecti

Degang Zhang

The low energy band structure of the FeAs based superconductors is fitted by a tight binding model with two Fe ions per unit cell and two degenerate orbitals per Fe ion. Based on this, superconductivity with extended s-wave pairing symmetry of the form $\cos k_x +\cos k_y$ is examined. The local density of states near an impurity is also investigated by usin

Vladislav V. Kravchenko, R. Michael Porter

We study conformal mappings from the unit disk to circular-arc quadrilaterals with four right angles. The problem is reduced to a Sturm-Liouville boundary value problem on a real interval, with a nonlinear boundary condition, in which the coefficient functions contain the accessory parameters t,lambda of the mapping problem. The parameter lambda is designed

Rubina Kotak, Peter Meikle, Duncan Farrah, Christopher Gerardy

We present mid-infrared (MIR) observations of the Type II-plateau supernova (SN) 2004et, obtained with the {\it Spitzer Space Telescope} between days 64 and 1406 past explosion. Late-time optical spectra are also presented. For the period 300-795 days past explosion, we argue that the spectral energy distribution of SN 2004et comprises (a) a hot component du

Diego Pazó, Ernest Montbrió

We investigate the transition to synchronization in the Kuramoto model with bimodal distributions of the natural frequencies. Previous studies have concluded that the model exhibits a hysteretic phase transition if the bimodal distribution is close to a unimodal one, due to the shallowness the central dip. Here we show that proximity to the unimodal-bimodal

Joachim Schnadt, Jan Knudsen, Xiao Liang Hu, Angelos Michaelides

The oxidized Ag(111) surface has been studied by a combination of experimental and theoretical methods, scanning tunneling microscopy (STM), x-ray photoelectron spectroscopy (XPS), and density functional theory (DFT). A large variety of different surface structures is found, depending on the detailed preparation conditions. The observed structures fall into

Kenta Hioki, Kei-ichi Maeda

A black hole casts a shadow as an optical appearance because of its strong gravitational field. We study how to determine the spin parameter and the inclination angle by observing the apparent shape of the shadow, which is distorted mainly by those two parameters. Defining some observables characterizing the apparent shape (its radius and distortion paramete

P. D. Dixit, S. Merchant, D. Asthagiri

The S$_2$ site of the KcsA K$^+$ channel has eight carbonyl ligands in the ion-binding site. A recent study suggests that the K$^+$-over-Na$^+$ selectivity of the S$_2$ site can be understood by noting the larger free energy change involved in enforcing an eight water coordination state around Na$^+$ relative to K$^+$. The free energies were obtained from th

Davide Mamone, Carlo Rovelli

We explore some second-order amplitudes in loop quantum gravity. In particular, we compute some second-order contributions to diagonal components of the graviton propagator in the large distance limit, using the old version of the Barrett-Crane vertex amplitude. We illustrate the geometry associated to these terms. We find some peculiar phenomena in the larg

Dmitry Zakharov

We construct a discrete analogue of the integrable two-dimensional Dirac operator and describe the spectral properties of its eigenfunctions. We construct an integrable discrete analogue of the modified Novikov-Veselov hierarchy. We derive the first two equations of the hierarchy and give explicit formulas for the eigenfunctions in terms of the theta-functio

Wei Zhang, Wei Zhang

In this paper, we numerically study energy dissipation caused by traffic in the Nagel-Schreckenberg (NaSch) model with open boundary conditions (OBC). Numerical results show that there is a nonvanishing energy dissipation rate Ed, and no true free-flow phase exists in the deterministic and nondeterministic NaSch models with OBC. In the deterministic case, th

J. T. Wright, A. W. Howard

We describe a technique for solving for the orbital elements of multiple planets from radial velocity (RV) and/or astrometric data taken with 1 m/s and microarcsecond precision, appropriate for efforts to detect Earth-massed planets in their stars' habitable zones, such as NASA's proposed Space Interferometry Mission. We include details of calculatin

André Martin

We prove that while the total cross{}-section is bounded by $(π/m_π^2) \ln^2 s$, where $s$ is the square of the c.m. energy and $m_π$ the mass of the pion, the total inelastic cross{}-section is bounded by $(1/4)(π/m_π^2) \ln^2 s$, which is 4 times smaller. We discuss the implications of this result on the total cross{}-section itself.

A. Mobius, U. K. Roessler

The ordering of charges on half-filled hypercubic lattices is investigated numerically, where electroneutrality is ensured by background charges. This system is equivalent to the $s = 1/2$ Ising lattice model with antiferromagnetic $1/r$ interaction. The temperature dependences of specific heat, mean staggered occupation, and of a generalized susceptibility

R. M. Albuquerque, S. Narison, M. Nielsen

We extract directly (for the first time) the charmed (C=1) and bottom (B=-1) heavy-baryons (spin 1/2 and 3/2) mass-splittings due to SU(3) breaking using double ratios of QCD spectral sum rules (QSSR) in full QCD, which are less sensitive to the exact value and definition of the heavy quark mass, to the perturbative radiative corrections and to the QCD conti

Mathias Garny, Markus Michael Muller

The nonequilibrium dynamics of quantum fields is an initial-value problem, which can be described by Kadanoff-Baym equations. Typically, and in particular when numerical solutions are demanded, these Kadanoff-Baym equations are restricted to Gaussian initial states. However, physical initial states are non-Gaussian correlated initial states. In particular, r

Hovhannes R. Grigoryan, T. -S. H. Lee, Ho-Ung Yee

We study nucleon-to-delta electromagnetic transition form factors and relations between them within the framework of holographic dual model of QCD proposed by Sakai and Sugimoto. In this setup, baryons appear as topological solitons of the five dimensional holographic gauge theory that describes a tower of mesons and their interactions. We find a relativisti

Barry Mazur, Karl Rubin

In this paper we investigate the 2-Selmer rank in families of quadratic twists of elliptic curves over arbitrary number fields. We give sufficient conditions on an elliptic curve so that it has twists of arbitrary 2-Selmer rank, and we give lower bounds for the number of twists (with bounded conductor) that have a given 2-Selmer rank. As a consequence, under

Benoit Estienne, Nicolas Regnault, Raoul Santachiara

Recently, Jack polynomials have been proposed as natural generalizations of Z_k Read-Rezayi states describing non-Abelian fractional quantum Hall systems. These polynomials are conjectured to be related to correlation functions of a class of W-conformal field theories based on the Lie algebra A_{k-1}. These theories can be considered as non-unitary solutions

Sven Zschocke, Sergei A. Klioner

Numerical integration of the differential equations of light propagation in the Schwarzschild metric shows that in some extreme situations relevant for practical observations (e.g. for Gaia) the well-known standard post-Newtonian formula for the boundary problem has an error up to 16 \muas. The aim of this note is to identify the reason for this error and to

A. I. Volokitin, B. N. J. Persson

Quite recently Philbin et al present new theory of the van der Waals friction at zero temperature. Contrary to the previous theory they claimed that there is no "quantum friction" due to quantum fluctuation of the electromagnetic field between two parallel plates moving relative to each other. We show that this theory is incorrect.

Dao Xuan Viet, Hikaru Kawamura

The nature of the ordering of the three-dimensional isotropic Heisenberg spin glass with nearest-neighbor random Gaussian coupling is studied by extensive Monte Carlo simulations. Several independent physical quantities are measured both for the spin and for the chirality, including the correlation-length ratio, the Binder ratio, the glass order parameter, t

Peter Leifer

A model of self-interacting quantum non-local Dirac's electron has been proposed. Its dynamics was revealed by the projective representation of operators corresponding to spin/charge degrees of freedom. Energy-momentum field is described by the system of quasi-linear "field-shell" PDE's following from the conservation law expressed by the aff

H. Allmaier, L. Chioncel, E. Arrigoni

We investigate electron correlation effects in stoichiometric Titanium Nitride (TiN) using a combination of electronic structure and many-body calculations. In a first step, the Nth-order muffin tin orbital technique is used to obtain parameters for the low-energy Hamiltonian in the Ti-d(t2g)-band manifold. The Coulomb-interaction U and the Hund's rule e

Michel Planat

Peres/Mermin arguments about no-hidden variables in quantum mechanics are used for displaying a pair (R, S) of entangling Clifford quantum gates, acting on two qubits. From them, a natural unitary representation of Coxeter/Weyl groups W(D5) and W(F4) emerges, which is also reflected into the splitting of the n-qubit Clifford group Cn into dipoles C$\pm$n . T

P. Manuel, L. C. Chapon, P. G. Radaelli, H. Zheng

We have studied the frustrated system YBaCo4O7 generally described as an alternating stacking of Kagome and triangular layers of magnetic ions on a trigonal lattice, by single crystal neutron diffraction experiments above the Neel ordering transition. Experimental data reveals pronounced magnetic diffuse scattering, which is successfully modeled by direct Mo

Scott M. Bailey, Nicolas Ricka

Computations involving the root invariant prompted Mahowald and Shick to develop the slogan: "the root invariant of v_n periodic homotopy is v_n torsion." While neither a proof, nor a precise statement, of this slogan appears in the literature, numerous authors have offered computational evidence in support of its fundamental idea. The root invariant

Jozef Devreese, Sasha Alexandrov

It is remarkable how the Froehlich polaron, one of the simplest examples of a Quantum Field Theoretical problem, as it basically consists of a single fermion interacting with a scalar Bose field of ion displacements, has resisted full analytical or numerical solution at all coupling since 1950, when its Hamiltonian was first written. The field has been a tes

Rong-Gen Cai, Li-Ming Cao, Nobuyoshi Ohta

We find topological (charged) black holes whose horizon has an arbitrary constant scalar curvature $2k$ in Hořava-Lifshitz theory. Without loss of generality, one may take $k=1,0$ and -1. The black hole solution is asymptotically AdS with a nonstandard asymptotic behavior. Using the Hamiltonian approach, we define a finite mass associated with the solution.

Hidefumi Ohsugi, Takayuki Hibi

In this paper, it is proved that, if a toric ideal possesses a fundamental binomial none of whose monomials is squarefree, then the corresponding semigroup ring is not very ample. Moreover, very ample semigroup rings of Lawrence type are discussed. As an application, we study very ampleness of configurations arising from contingency tables.

A. G. Akeroyd, Mayumi Aoki, Hiroaki Sugiyama

Singly and doubly charged Higgs bosons in the Higgs Triplet Model mediate the lepton flavour violating (LFV) decays tau to \bar{l}ll and mu to e gamma. The LFV decay rates are proportional to products of two triplet Yukawa couplings (h_{ij}) which can be expressed in terms of the parameters of the neutrino mass matrix and an unknown triplet vacuum expectatio

Arindam Mitra

No theory of physics has been collectively scientifically verified in an experiment so far. It is pointed out that probabilistic structure of quantum theory can be collectively scientifically verified in an experiment. It is also argued that experimentalist point of view quantum theory is a complete theory.

Haozhao Liang, Nguyen Van Giai, Jie Meng

Self-consistent random phase approximation (RPA) approaches in the relativistic framework are applied to calculate the isospin symmetry-breaking corrections $δ_c$ for the $0^+\to0^+$ superallowed transitions. It is found that the corrections $δ_c$ are sensitive to the proper treatments of the Coulomb mean field, but not so much to specific effective interact

Masanori Asakura, Kanetomo Sato

In this paper, we study an analogue of the Tate conjecture for $K_2$ of U, the complement of split multiplicative fibers in an elliptic surface. A main result is to give an upper bound of the rank of the Galois fixed part of the etale cohomology $H^2(\bar{U},Q_p(2))$. As an application, we give an elliptic K3 surface $X$ over a p-adic field for which the tor

Guo-Ping Guo, Zhi-Rong Lin, Tao Tu, Hai-Ou Li

We develop an architecture for distributed quantum computation using quantum bus of plasmonic circuits and spin qubits in self-assembled quantum dots. Deterministic quantum gates between two distant spin qubits can be reached by using an adiabatic approach in which quantum dots couple with highly detuned plasmon modes in a metallic nanowire. Plasmonic quantu

Denis Comtesse, Alfred Hucht, Daniel Grüneberg

We consider systems with slab geometry of finite thickness L that undergo second order phase transitions in the bulk limit and belong to the universality class of O(n)-symmetric systems with short-range interactions. In these systems the critical fluctuations at the bulk critical temperature T_c induce a long-range effective force called the "thermodynam

Gouranga C Nayak

We study Higgs production and decay from TeV scale string balls in $pp$ collisions at $\sqrt{s}$ = 14 TeV at LHC. We present the results of total cross section of diphotons, invariant mass distribution of the diphotons and $p_T$ distribution of the diphotons and $ZZ$ pairs from Higgs from string balls at LHC. We find that the invariant mass distribution of d

Bruno Küng, Simon Gustavsson, Theodore Choi, Ivan Shorubalko

We measure the shot noise of a quantum point-contact using a capacitively coupled InAs double quantum dot as an on-chip sensor. Our measurement signals are the (bidirectional) interdot electronic tunneling rates which are determined by means of time-resolved charge sensing. The detector frequency is set by the relative detuning of the energy levels in the tw

Yu-Ying Zhang, Thomas H Reiprich, Alexis Finoguenov, Daniel S. Hudson

Mahdavi et al. find that the degree of agreement between weak lensing and X-ray mass measurements is a function of cluster radius. Numerical simulations also point out that X-ray mass proxies do not work equally well at all radii. The origin of the effect is thought to be associated with cluster mergers. Recent work presenting the cluster maps showed an abil

Marc Quincampoix, Jérôme Renault

We investigate a limit value of an optimal control problem when the horizon converges to infinity. For this aim, we suppose suitable nonexpansive-like assumptions which does not imply that the limit is independent of the initial state as it is usually done in the literature.

K. K. Yadav

The TACTIC gamma-ray telescope, equipped with a tracking light collector of $\sim$9.5m$^2$ area and a 349-pixel imaging camera has been in operation at Mount Abu in Western India since 2001. Having a sensitivity of detecting the Crab Nebula above 1.2 TeV at 5.0$\sigma$ significance level in 25h of observations, this telescope has detected gamma-ray emissions

Luca Fontanesi, Michiel Wouters, Vincenzo Savona

We study the one-dimensional Bose gas in spatially correlated disorder at zero temperature, using an extended density-phase Bogoliubov method. We analyze in particular the decay of the one-body density matrix and the behaviour of the Bogoliubov excitations across the phase boundary. We observe that the transition to the Bose glass phase is marked by a power-

C. E. Mora, M. Piani, A. Miyake, M. Van den Nest

We investigate which quantum states can serve as universal resources for approximate and stochastic measurement-based quantum computation, in the sense that any quantum state can be generated from a given resource by means of single-qubit (local) operations assisted by classical communication. More precisely, we consider the approximate and stochastic genera

Burra G. Sidharth

In the theory of the Dirac equation and in the standard model, the neutrino is massless. Both these theories use Lorentz invariance. In modern approaches however, spacetime is no longer smooth, and this modifies special relativity. We show how such a modification throws up the mass of the (electron) neutrino.

Fabien Campillo, Marc Joannides

An individual-based model (IBM) of a spatiotemporal terrestrial ecological population is proposed. This model is spatially explicit and features the position of each individual together with another characteristic, such as the size of the individual, which evolves according to a given stochastic model. The population is locally regulated through an explicit

Diana Sophia Codat

The level of development of the electronic communication market and of the information technology, the indicators regarding the penetration of Internet and the level of penetration of the connections in wide band, the integration degree of the Tic application in the business area are crucial for the development of an informational society and for the creatio

Hu Young Jeong, Jeong Yong Lee, Sung-Yool Choi, Jeong Won Kim

We report a direct observation of the microscopic origin of the bipolar resistive switching behavior in nanoscale titanium oxide films. Through a high-resolution transmission electron microscopy, an analytical TEM technique using energy-filtering transmission electron microscopy and an in situ x-ray photoelectron spectroscopy, we demonstrated that the oxygen

Gil Jannes

It is widely hoped that quantum gravity will shed light on the question of the origin of time in physics. The currently dominant approaches to a candidate quantum theory of gravity have naturally evolved from general relativity, on the one hand, and from particle physics, on the other hand. A third important branch of 20th century `fundamental' physics,

Masahiro Kawasaki, Kazunori Kohri, Kazunori Nakayama

We study the annihilating dark matter contribution to the extra-galactic diffuse gamma-ray background spectrum, motivated by the recent observations of cosmic-ray positron/electron anomalies. The observed diffuse gamma-ray flux provides stringent constraint on dark matter models and we present upper bounds on the annihilation cross section of the dark matter

Shesansu Sekhar Pal

The supergravity solutions to various $p$-branes are presented and typically it breaks one quarter of supersymmetry except for the D1 brane case, where it breaks one half of supersymmetry and are manifestly non-relativistic in nature. The symmetries that the solutions enjoys are that of space and time translations, rotations, boosts but without any scaling a

Yu-Ao Chen, Xiao-Hui Bao, Zhen-Sheng Yuan, Shuai Chen

We report the observation of phase-super resolution in a motion-sensitive spin-wave (SW) atom interferometer utilizing a NOON-type entanged state. The SW interferometer is implemented by generating a superposition of two SWs and observing the interference between them, where the interference fringe is sensitive to the atomic collective motion. By heralded ge

Michael Gary, Steven B. Giddings

We investigate recovery of the bulk S-matrix from the AdS/CFT correspondence, at large radius. It was recently argued that some of the elements of the S-matrix might be read from CFT correlators, given a particular singularity structure of the latter, but leaving the question of more general S-matrix elements. Since in AdS/CFT, data must be specified on the

Ryan C. Hickox

Extragalactic X-ray surveys are exceptionally powerful tools for studying the evolution of supermassive black holes and their host galaxies, by detecting large numbers of active galactic nuclei (AGN) and star-forming galaxies over a wide range of redshifts and cosmic environments. With its sensitivity and superb angular resolution, Chandra has been at the fo

Sergei I. Blinnikov

A few remarks on Dark Matter (DM) models are presented. An example is Mirror Matter which is the oldest but still viable DM candidate, perhaps not in the purest form. It can serve as a test-bench for other analogous DM models, since the properties of macroscopic objects are quite firmly fixed for Mirror Matter. A pedagogical derivation of virial theorem is g

Béchir Amri, Jean-Philippe Anker, Mohamed Sifi

In this article, we establish first a geometric Paley-Wiener theorem for the Dunkl transform in the crystallographic case. Next we obtain an optimal bound for the $L^p\to L^p$ norm of Dunkl translations in dimension 1. Finally we describe more precisely the support of the distribution associated to Dunkl translations in higher dimension.

Basudeb Dasgupta, Amol Dighe, Georg G. Raffelt, Alexei Yu. Smirnov

Collective oscillations of supernova neutrinos swap the electron neutrino and antineutrino spectra with those of another flavor in certain energy intervals bounded by sharp spectral splits. This phenomenon is far more general than previously appreciated: typically one finds one or more swaps and accompanying splits in the neutrino and antineutrino channels f

Horatiu Nastase

In this note we search for large distance solutions of Horava gravity. In the case of the "detailed balance" action, gravity solutions asymptote to IR only above the cosmological constant ($\sim$horizon) scale. However, if one adds IR dominant terms $αR^{(3)}+βΛ_W$, one can recover general relativity solutions on usual scales in the real Universe, pr

D. V. Alekseevsky, Yu. G. Nikonorov

A homogeneous Riemannian space $(M= G/H,g)$ is called a geodesic orbit space (shortly, GO-space) if any geodesic is an orbit of one-parameter subgroup of the isometry group $G$. We study the structure of compact GO-spaces and give some sufficient conditions for existence and non-existence of an invariant metric $g$ with homogeneous geodesics on a homogeneous

Satoshi Fujimoto

We propose an experimental scheme to detect unambiguously parity-mxing of Cooper pairs in noncentrosymmetric superconductors, which utilizes crossed Andreev reflection processes between two oppositely spin-polarized normal metal leads and a noncentrosymmetric superconductor. It is demonstrated that a non-local conductance exhibits a clear signature of parity

J. D. do Nascimento, M. Castro, J. Melendez, M. Bazot

We analyze the non-standard mixing history of the solar twins HIP 55459, HIP 79672, HIP 56948, HIP 73815, and HIP 100963, to determine as precisely as possible their mass and age. We computed a grid of evolutionary models with non-standard mixing at several metallicities with the Toulouse-Geneva code for a range of stellar masses assuming an error bar of +-5

V. N. Berestovskii, C. P. Plaut

We prove that every length space X is the orbit space (with the quotient metric) of an R-tree T via a free action of a locally free subgroup G(X) of isometries of X. The mapping f:T->X is a kind of generalized covering map called a URL-map and is universal among URL-maps onto X. T is the unique R-tree admitting a URL-map onto X. When X is a complete Riemanni

G. Y. Wang, K. H. Wong, Y. Wang

A-site ordered manganites $R$BaMn$_{2}$O$_{6}$ ($R$ = La, Pr, Nd, Sm) were synthesized and the oxygen isotope effect in them was studied. It was found that the substitution of $^{16}$O by $^{18}$O has caused increases in both the Neel temperature ($T$$_{N}$) and the charge ordering temperature ($T$$_{CO}$) and an decrease in the Curie temperature ($T$$_{C}$)

L. J. Hou, A. Piel, P. K. Shukla

Reply to the comment [arXiv:0904.2989] on "Self-Diffusion in 2D Dusty-Plasma Liquids: Numerical-Simulation Results" [arXiv:0812.0338]

Eric Vanden-Eijnden, Maddalena Venturoli

A sampling procedure to compute exactly the rate of activated processes arising in systems at equilibrium or nonequilibrium steady state is presented. The procedure is a generalization of the method in [A. Warmflash, P. Bhimalapuram, and A. R. Dinner, J. Chem. Phys., 127, 154112 (2007); A. Dickson, A. Warmflash, and A. R. Dinner, J. Chem. Phys., 130, 074104

Andrey Vladimirov

This research was motivated by the recent observations indicating very strong magnetic fields at some supernova remnant shocks, which suggests in-situ generation of magnetic turbulence. The dissertation presents a numerical model of collisionless shocks with strong amplification of stochastic magnetic fields, self-consistently coupled to efficient shock acce

S. McHugh, R. Jaafar, M. P. Sarachik, Y. Myasoedov

Using micron-sized thermometers and Hall bars, we report time-resolved studies of the local temperature and local magnetization for two types of magnetic avalanches (abrupt spin reversals) in the molecular magneti Mn12-acetate, corresponding to avalanches of the main slow-relaxing crystalline form and avalanches of the fast-relaxing minor species that exists

F. Pascoal, L. C. Céleri, S. S. Mizrahi, M. H. Y. Moussa

We analyze the dynamical Casimir effect for a massless scalar field confined between two concentric spherical shells which impose on the field mixed boundary conditions. We thus complement a previous result [Phys. Rev. A \textbf{78}, 032521 (2008)], where the same problem was considered but in that case the field was submitted to a Dirichlet boundary conditi

Ingve Simonsen, Age Larsen, Erik Andreassen, Espen Ommundsen

Approximate analytic expressions for haze (and gloss) of Gaussian randomly rough surfaces for various types of correlation functions are derived within phase-perturbation theory. The approximations depend on the angle of incidence, polarization of the incident light, the surface roughness, $σ$, and the average of the power spectrum taken over a small angular

Ugo Moschella, Richard Schaeffer

We describe a new viewpoint on canonical quantization of linear fields on a general curved background that encompasses and generalizes the standard treatment of canonical QFT given in textbooks. Our method permits the construction of pure states and mixed stated with the same technique. We apply our scheme to the study of Rindler QFT and we present a new der

Massimo Marengo, Mayly C. Sanchez

We present a statistical method for the photometric search of rare astronomical sources based on the weighted k-NN method. A metric is defined in a multi-dimensional color-magnitude space based only on the photometric properties of template sources and the photometric uncertainties of both templates and data, without the need to define ad-hoc color and magni

Kim L. Phan, Peter G. Steeneken, Martijn J. Goossens, Gerhard E. J. Koops

There is a large interest to decrease the size of mechanical oscillators since this can lead to miniaturization of timing and frequency referencing devices, but also because of the potential of small mechanical oscillators as extremely sensitive sensors. Here we show that a single crystal silicon resonator structure spontaneously starts to oscillate when dri

A. Georgakakis, A. L. Coil, E. S. Laird, R. L. Griffith

We use morphological information of X-ray selected AGN hosts to set limits on the fraction of the accretion density of the Universe at z~1 that is not likely to be associated with major mergers. Deep X-ray observations are combined with high resolution optical data from the Hubble Space Telescope in the AEGIS, GOODS North and GOODS South fields to explore th

David Eppstein, Emma S. Spiro

We describe a data structure that maintains the number of triangles in a dynamic undirected graph, subject to insertions and deletions of edges and of degree-zero vertices. More generally it can be used to maintain the number of copies of each possible three-vertex subgraph in time O(h) per update, where h is the h-index of the graph, the maximum number such

Alexei Borodin, Persi Diaconis, Jason Fulman

Adding a column of numbers produces "carries" along the way. We show that random digits produce a pattern of carries with a neat probabilistic description: the carries form a one-dependent determinantal point process. This makes it easy to answer natural questions: How many carries are typical? Where are they located? We show that many further exampl

Alwyn Wootten, A. Richard Thompson

The Atacama Large Millimeter/submillimeter Array (ALMA) is an international radio telescope under construction in the Atacama Desert of northern Chile. ALMA is situated on a dry site at 5000 m elevation, allowing excellent atmospheric transmission over the instrument wavelength range of 0.3 to 10 mm. ALMA will consist of two arrays of high-precision antennas

Silvia Picozzi, Claude Ederer

Multiferroics, materials where spontaneous long-range magnetic and dipolar orders coexist, represent an attractive class of compounds, which combine rich and fascinating fundamental physics with a technologically appealing potential for applications in the general area of spintronics. Ab-initio calculations have significantly contributed to recent progress i

S. J. Williams, D. R. Gies, R. A. Matson, W. Huang

We present a spectroscopic and photometric analysis of the remarkable massive binary system, BD +36 4063. We argue that the visible ON star is undergoing a rapid mass transfer episode that results in a thick and opaque disk that surrounds and renders invisible its massive companion. A comparison of the projected rotational velocity and the orbital semiamplit

I. Stetcu, S. Quaglioni, J. L. Friar, A. C. Hayes

The electric dipole polarizabilities of $^3$H, $^3$He, and $^4$He are calculated directly using the Schrödinger equation with the latest generation of two- and three-nucleon interactions. These polarizabilities are necessary in order to obtain accurate nuclear-polarization corrections for transitions involving S-waves in one- and two-electron atoms. Our resu

Hyo Chul Ahn, Deog Ki Hong, Cheonsoo Park, Sanjay Siwach

We study the 5D Rarita-Schwinger fields to describe spin 3/2 baryons in AdS/QCD. We calculate the spectrum of spin 3/2 baryons (Delta resonances) and their form factors, together with meson-baryon couplings from AdS/QCD. The transition form-factors between Delta and nucleon are evaluated. Both pion and rho meson couplings have the same origin in the bulk and

Bernd A. Kniehl, Oleg V. Tarasov

The method for obtaining functional equations, recently proposed by one of the authors, is applied to one-loop box integrals needed in calculations of radiative corrections to heavy-quark production and Bhabha scattering. We present relationships between these integrals with different arguments and box integrals with all propagators being massless. It turns

Xianpeng Hu, Dehua Wang

The relationship between the compressible magnetohydrodynamic flows with low Mach number and the incompressible magnetohydrodynamic flows is investigated. More precisely, the convergence of weak solutions of the compressible isentropic viscous magnetohydrodynamic equations to the weak solutions of the incompressible viscous magnetohydrodynamic equations is p

M. Pestalozzi, M. Elitzur, J. Conway

A strong signature of a circumstellar disc around a high-mass protostar has been inferred from high resolution methanol maser observations in NGC7538-IRS1 N. This interpretation has however been challenged with a bipolar outflow proposed as an alternative explanation. We compare the two proposed scenarios for best consistency with the observations. Using a n

Dmitri I. Panyushev

Let $G$ be a semisimple algebraic group and $B$ a Borel subgroup. We consider generalisations of Lusztig's q-analogues of weight multiplicity, where the set of positive roots is replaced with the multiset of weights of a $B$-submodule of an arbitrary finite-dimensional $G$-module.

C. Opagiste, C. Paulsen, E. Lhotel, P. Rodiere

A high-quality single crystal of Ce3Pt23Si11 has been grown using the Czochralski method. The crystal structure is presented and the chemical composition has been checked using an electron microprobe analyzer. Measurements of the electrical resistivity and magnetic susceptibility performed at low temperature show a ferromagnetic transition at Tc = 0.44 K.

Nicole Lemire, Jan Minac, Andrew Schultz, John Swallow

Let p>2 be prime, and let n,m be positive integers. For cyclic field extensions E/F of degree p^n that contain a primitive pth root of unity, we show that the associated F_p[Gal(E/F)]-modules H^m(G_E,mu_p) have a sparse decomposition. When E/F is additionally a subextension of a cyclic, degree p^{n+1} extension E'/F, we give a more refined F_p[Gal(E/F)]-

K. Yermashov, K. H. Siemsen, K. Wolke, R. A. Rasenack

The idea of the Neurath Basic Model View Controller (NBMVC) appeared during the discussion of the design of domain-specific modeling tools based on the Neurath Modeling Language [Yer06]. The NBMVC is the core of the modeling process within the modeling environment. It reduces complexity out of the design process by providing domain-specific interfaces betwee

Karsten Wolke, K. Yermashov, K. H. Siemsen, Rolf Andreas Rasenack

Computing systems are becoming more and more complex and assuming more and more responsibilities in all sectors of human activity. Applications do not run locally on a single computer any more. A lot of today's applications are built as distributed system; with services on different computers communicating with each other. Distributed systems arise every

Radu Vultur

Whether you just want to take a peek of a remote computer status, or you want to install the latest version of a software on several workstations, you can do all of this from your computer. The networks are growing, the time spent administering the workstations increases and the number of repetitive tasks is going sky high. But here comes MESH to take that l

Mihai Timis

In present paper, I propose a method for resolving the timing delays for output signals from an asynchronous sequential system. It will be used an example of an asynchronous sequential system that will set up an output signal when an input signal will be set up. The width of the output signal depends on the input signal width, and in this case it is very sho

Johan Bijnens

The present status of Chiral Perturbation Theory (ChPT) in the strong mesonic sector is discussed. A very short introduction to ChPT is followed by an overview of existing two-loop calculations and the determination of the Low-Energy-Constants (LECs). I discuss the case of $η\toπππ$ decays in somewhat more detail and finish by mentioning some recent work on

S. Bordacs, D. Varjas, I. Kezsmarki, G. Mihaly

We demonstrate that the onset of complex spin orders in ACr$_2$O$_4$ spinels with magnetic A$=$Co, Fe and Cu ions lowers the lattice symmetry. This is clearly indicated by the emergence of anisotropic lattice dynamics -- as evidenced by the pronounced phonon splittings -- even when experiments probing static distortions fail. We show that the crystal symmetr

Mihai Timis

In present paper, I propose a method for resolving the timing delays for output signals from an asynchronous sequential system. It will be used an example of an asynchronous sequential system that will set up an output signal when an input signal will be set up. The width of the output signal depends on the input signal width, and in this case it is very sho

S. A. Mikhailov

The many-body theory of a uniform electron gas was developed at the end of 1950ies. The Coulomb interaction between electrons was considered as a perturbation and the ground state energy was calculated in all orders of the non-degenerate perturbation theory. We show that the ground state of the unperturbed system is actually strongly degenerate and that the

Milind V. Diwan

MINOS is an accelerator neutrino oscillation experiment at Fermilab. An intense high energy neutrino beam is produced at Fermilab and sent to a near detector on the Fermilab site and also to a 5 kTon far detector 735 km away in the Soudan mine in northern Minnesota. The experiment has now had several years of running with millions of events in the near detec

Johan Bijnens, Ilaria Jemos

We present the results of a search for relations between observables that are independent of the Chiral Pertubation Theory (ChPT) Next-to-Next-to-Leading Order (NNLO) Low-Energy Constants (LECs). We have found some relations between observables in $ππ$, $πK$ scattering and $K_{l4}$ decay which have been evaluated numerically using the old fit (fit 10 in [1]

Guillaume Erétéo, Fabien Gandon, Olivier Corby, Michel Buffa

Social Network Analysis (SNA) tries to understand and exploit the key features of social networks in order to manage their life cycle and predict their evolution. Increasingly popular web 2.0 sites are forming huge social network. Classical methods from social network analysis (SNA) have been applied to such online networks. In this paper, we propose leverag

Valerie Hower, Christine E. Heitsch

We extend recent methods for parametric sequence alignment to the parameter space for scoring RNA folds. This involves the construction of an RNA polytope. A vertex of this polytope corresponds to RNA secondary structures with common branching. We use this polytope and its normal fan to study the effect of varying three parameters in the free energy model th