August 2010 arXiv papers — page 50
Showing 4,901–5,000 of 5,306 papers
L. P. G. De Assis, Patricio Gaete, José A. Helaÿel-Neto, S. O. Vellozo
In the framework of three-dimensional Born-Infeld Electrodynamics, we pursue an investigation of the consequences of the space-time dimensionality on the existence of magnetostatic fields generated by electric charges at rest in an inertial frame, which are present in its four-dimensional version. Our analysis reveals interesting features of the model. In fa
L. M. Haffner
Ionized nebulae have been targets of interest since the introduction of the telescope centuries ago. These isolated, "classical" H II regions gave us some of the earliest insight into the copious feedback energy that stars inject into the interstellar medium. Their unique spectra contain information about the quality and quantity of the ionizing fiel
János Kollár
This is a survey paper discussing the moduli problem for varieties of general type.
Frank Bauer
Choosing the regularization parameter for inverse problems is of major importance for the performance of the regularization method. We will introduce a fast version of the Lepskij balancing principle and show that it is a valid parameter choice method for Tikhonov regularization both in a deterministic and a stochastic noise regime as long as minor condition
A meshless numerical solution of the family of generalized fifth-order Korteweg-de Vries equations
math.NASyed Tauseef Mohyud-Din, Elham Negahdary, Muhammad Usman
In this paper we present a numerical solution of a family of generalized fifth-order Korteweg-de Vries equations using a meshless method of lines. This method uses radial basis functions for spatial derivatives and Runge-Kutta method as a time integrator. This method exhibits high accuracy as seen from the comparison with the exact solutions.
Jean-François Burnol
We modify the classical Paley-Wiener spaces $PW_x$ of entire functions of finite exponential type at most $x>0$, which are square integrable on the real line, via the additional condition of vanishing at finitely many complex points $z_1, ..., z_n$. We compute the reproducing kernels and relate their variations with respect to $x$ to a Krein differential sys
L. M. Haffner, R. J. Reynolds, G. J. Madsen, A. S. Hill
After a successful eleven-year campaign at Kitt Peak, we moved the Wisconsin H-Alpha Mapper (WHAM) to Cerro Tololo in early 2009. Here we present some of the early data after a few months under southern skies. These maps begin to complete the first all-sky, kinematic survey of the diffuse H-alpha emission from the Milky Way. Much of this emission arises from
D. Moretti, D. Felinto, J. W. R. Tabosa
We report a detailed investigation on the generation of pulse pairs during the readout of a coherence grating stored in a cold atomic ensemble. The pulse shapes and the split of the retrieved energy between the two pulses are studied as a function of the relative intensities of the two reading fields, and a minimum is observed for the total retrieved energy.
Size distribution and waiting times for the avalanches of the Cell Network Model of Fracture
cond-mat.softGabriel Villalobos, Ferenc Kun, Dorian L. Linero, Jose D. Muñoz
The Cell Network Model is a fracture model recently introduced that resembles the microscopical structure and drying process of the parenchymatous tissue of the Bamboo Guadua angustifolia. The model exhibits a power-law distribution of avalanche sizes, with exponent -3.0 when the breaking thresholds are randomly distributed with uniform probability density.
M. Gomes, J. R. Nascimento, A. Yu. Petrov, A. J. da Silva
We study the generation of aether-like Lorentz-breaking actions in three, four and five dimensions via an appropriate Lorentz-breaking coupling of electromagnetic and spinor fields. Special attention is given to the four-dimensional case where we discuss the issue of ambiguities.
Blaz Krese, Matjaz Perc, Edvard Govekar
We examine the dynamics of laser droplet generation in dependence on the detachment pulse power. In the absence of the detachment pulse, undulating pendant droplets are formed at the end of a properly fed metal wire due to the impact of the primary laser pulse that induces melting. Eventually, these droplets detach, i.e. overcome the surface tension, because
Design drivers for a wide-field multi-object spectrograph for the William Herschel Telescope
astro-ph.IMMarc Balcells, Chris R. Benn, David Carter, Gavin B. Dalton
Wide-field multi-object spectroscopy is a high priority for European astronomy over the next decade. Most 8-10m telescopes have a small field of view, making 4-m class telescopes a particularly attractive option for wide-field instruments. We present a science case and design drivers for a wide-field multi-object spectrograph (MOS) with integral field units
Anthony Várilly-Alvarado, Bianca Viray
We construct an Enriques surface X over Q with empty étale-Brauer set (and hence no rational points) for which there is no algebraic Brauer-Manin obstruction to the Hasse principle. In addition, if there is a transcendental obstruction on X, then we obtain a K3 surface that has a transcendental obstruction to the Hasse principle.
Constraints from Unrealistic Vacua in Supersymmetric Standard Model with Neutrino Mass Operators
hep-phYoshimi Kanehata, Tatsuo Kobayashi, Yasufumi Konishi, Takashi Shimomura
We analyze a scalar potential of the minimal supersymmetric standard model (MSSM) with neutrino mass operators along Unbounded-From-Below (UFB) and Color and/or Charged Breaking (CCB) directions. We show necessary conditions to avoid the potential minima which can be deeper than the realistic vacuum. These conditions would constrain more strongly than condit
Benoit Roland
The two calorimeters CASTOR and ZDCs enhance the hermeticity of the CMS detector at the LHC by extending the rapidity coverage in the forward region. After having described these detectors, their forward physics capabilities are presented. These latters include the study of parton shower, multiple parton interactions, diffraction and ultra high energy cosmic
Slowly rotating Kerr black hole as a solution of Einstein-Cartan gravity extended by a Chern-Simons term
gr-qcMauro Cambiaso, Luis F. Urrutia
We consider the nondynamical Chern-Simons (CS) modification to General Relativity (GR) in the framework of the Einstein-Cartan formulation, as providing a way to incorporate a slowly rotating Kerr black hole in the space of solutions. Our proposal lies on considering the CS term as a source of torsion and on an iterative procedure to look for vacuum solution
Svetlana V. Shinkareva, Vladimir Gudkov, Jing Wang
In this work we focus on examination and comparison of whole-brain functional connectivity patterns measured with fMRI across experimental conditions. Direct examination and comparison of condition-specific matrices is challenging due to the large number of elements in a connectivity matrix. We present a framework that uses network analysis to describe condi
Christopher Bradley
A Wallace-Simson line of a point J has the property that it passes through the midpoint Q of HJ, where H is the orthocentre. By allowing Q to move on the perpendicular bisector of HJ we obtain generalized Wallace-Simson lines. These turn out to be known in another context.
Malik Magdon-Ismail
We focus the use of \emph{row sampling} for approximating matrix algorithms. We give applications to matrix multipication; sparse matrix reconstruction; and, \math{\ell_2} regression. For a matrix \math{\matA\in\R^{m\times d}} which represents \math{m} points in \math{d\ll m} dimensions, all of these tasks can be achieved in \math{O(md^2)} via the singular v
Claire I. Levaillant
The Lawrence-Krammer representation was used in $2000$ to show the linearity of the braid group. The problem had remained open for many years. The fact that the Lawrence-Krammer representation of the braid group is reducible for some complex values of its two parameters is now known, as well as the complete description of these values under some restrictions
Pedro Teixeira
k is a field of characteristic p>0, and l_1,...,l_n are linear forms in k[x,y]. Intending applications to Hilbert--Kunz theory, to each triple C=(F,G,H) of nonzero homogeneous elements of k[x,y] we associate a function delta_C that encodes the "syzygy gaps" of F^q, G^q, and H^q*l_1^{a_1}*...*l_n^{a_n}, for all q=p^e and a_i<= q. These are close relat
K. Tullney, C. Gemmel, W. Heil, S. Karpuk
To test Lorentz symmetry we used a 3He/129Xe co-magnetometer. We will give a short summary of our experimental setup and the results of our latest measurements. We obtained preliminary results for the equatorial component of the background field interacting with the spin of the bound neutron: b_n < 3.72 x 10^(-32) GeV (95 C.L.).
Introducing students to the culture of physics: Explicating elements of the hidden curriculum
physics.ed-phEdward F. Redish
When we teach physics to prospective scientists and engineers we are teaching more than the "facts" of physics - more, even, than the methods and concepts of physics. We are introducing them to a complex culture - a mode of thinking and the cultural code of behavior of a community of practicing scientists. This culture has components that are often p
Sang Pyo Kim
In the in-/out-state formalism we find the exact one-loop effective action of a massive scalar field in the global coordinates of de Sitter spaces, which is a gravity analog of the Heisenberg-Euler action in QED. The nonperturbative effective action, modulo the angular momentum sum, has an imaginary part in all even dimensions, but the imaginary part of the
Wiet de Ronde, Filipe Tostevin, Pieter Rein ten Wolde
In this paper we show that living cells can multiplex biochemical signals, i.e. transmit multiple signals through the same signaling pathway simultaneously, and yet respond to them very specifically. We demonstrate how two binary input signals can be encoded in the concentration of a common signaling protein, which is then decoded such that each of the two o
Patrick Baumann, Iván Ramírez, Jorge Meléndez, Martin Asplund
We have determined precise stellar parameters and lithium abundances in a sample of 117 stars with basic properties very similar to the Sun. This sample selection reduces biasing effects and systematic errors in the analysis. We estimate the ages of our sample stars mainly from isochrone fitting but also from measurements of rotation period and X-ray luminos
Leonid Galtchouk, Isaac Sonin
It is well known that if a submartingale $X$ is bounded then the increasing predictable process $Y$ and the martingale $M$ from the Doob decomposition $% X=Y+M$ can be unbounded. In this paper for some classes of increasing convex functions $f$ we will find the upper bounds for $\lim_n\sup_XEf(Y_n)$, where the supremum is taken over all submartingales $(X_n)
A boundary element regularised Stokeslet method applied to cilia and flagella-driven flow
physics.flu-dynDavid J. Smith
A boundary element implementation of the regularised Stokeslet method of Cortez is applied to cilia and flagella-driven flows in biology. Previously-published approaches implicitly combine the force discretisation and the numerical quadrature used to evaluate boundary integrals. By contrast, a boundary element method can be implemented by discretising the fo
St. Reimann, V. Gontis, M. Alaburda
The dynamics of the {\em generalized} CEV process $dX_t = aX_t^n dt+ bX_t^m dW_t$ $(gCEV)$ is due to an interplay of two feedback mechanisms: State-to-Drift and State-to-Diffusion, whose degrees are $n$ and $m$ respectively. We particularly show that the gCEV, in which both feedback mechanisms are {\sc positive}, i.e. $n,m>1$, admits a stationary probability
Ab initio analysis of the x-ray absorption spectrum of the myoglobin-carbon monoxide complex: Structure and vibrations
cond-mat.softG. Veronesi, C. Degli Esposti Boschi, L. Ferrari, G. Venturoli
We present a comparison between Fe K-edge x-ray absorption spectra of carbonmonoxy-myoglobin and its simulation based on density-functional theory determination of the structure and vibrations and spectral simulation with multiple-scattering theory. An excellent comparison is obtained for the main part of the molecular structure without any structural fittin
Changes in the Cloud Belts of Jupiter, 1630-1664, as reported in the 1665 Astronomia Reformata of Giovanni Battista Riccioli
astro-ph.EPChristopher M. Graney
A translation of a section from the 1665 Astronomia Reformata of G. B. Riccioli discussing the appearance of the disk of Jupiter during the years 1630-1664; changes in the Jovian cloud belts as recorded by a variety of observers are a major feature of Riccioli's discussion.
Discrete maximum principle and a Delaunay-type mesh condition for linear finite element approximations of two-dimensional anisotropic diffusion problems
math.NAWeizhang Huang
The finite element solution of two-dimensional anisotropic diffusion problems is considered. A Delaunay-type mesh condition is developed for linear finite element approximations to satisfy a discrete maximum principle. The condition is shown to be weaker than the existing anisotropic non-obtuse angle condition. It reduces to the well known Delaunay condition
V. Bosch-Ramon
Gamma-ray binaries are suitable sources to study high-energy processes in jets and outflows in general. In the last years, there has been a lot of activity in the field of gamma-ray binaries to identify the different factors that shape their non-thermal spectra, which ranges from radio to very high energies, as well as their lightcurves. In this work, I disc
Compactness and invariance properties of evolution operators associated with Kolmogorov operators with unbounded coefficients
math.APLuciana Angiuli, Luca Lorenzi
In this paper we consider nonautonomous elliptic operators ${\mathcal A}$ with nontrivial potential term defined in $I\times\mathbb R^d$, where $I$ is a right-halfline (possibly $I=\mathbb R$). We prove that we can associate an evolution operator $(G(t,s))$ with ${\mathcal A}$ in the space of all bounded and continuous functions on $\mathbb R^d$. We also stu
M. A. Reynolds, M. T. Shouppe
Bertrand's theorem proves that inverse square and Hooke's law-type central forces are the only ones for which all bounded orbits are closed. Similar analysis was used to show that for other central force laws there exist closed orbits for a discrete set of angular momentum and energy values. These orbits can in general be characterized as ``spirograp
T. Muñoz-Darias, S. Motta, T. M. Belloni
We present the rms-intensity diagram for black hole transients. Using observations taken with the Rossi X-ray timing explorer we study the relation between the root mean square (rms) amplitude of the variability and the net count-rate during the 2002, 2004 and 2007 outbursts of the black hole X-ray binary GX 339-4. We find that the rms-flux relation previous
Invariant densities and escape rates: Rigorous and computable approximations in the $L^{\infty}$-norm
math.DSWael Bahsoun, Christopher Bose
In this article we study a piecewise linear discretization schemes for transfer operators (Perron-Frobenius operators) associated with interval maps. We show how these can be used to provide rigorous {\bf pointwise} approximations for invariant densities of Markov interval maps. We also derive the order of convergence of the approximate invariant density to
Marco Stangalini, Francesco Berrilli, Dario Del Moro, Roberto Piazzesi
In the framework of a 4m class Solar Telescope we studied the performance of the MCAO using the LOST simulation package. In particular, in this work we focus on two different methods to reduce the time delay error which is particularly critical in solar adaptive optics: a) the optimization of the wavefront reconstruction by reordering the modal base on the b
Merse E. Gáspár, István Rácz
As a preparation for the dynamical investigations, this paper begins with a short review of the three-layer gravastar model with distinguished attention to the structure of the pertinent parameter space of gravastars in equilibrium. Then the radial stability of these types of gravastars is studied by determining their response for the totally inelastic colli
First Kepler results on compact pulsators V: Slowly pulsating subdwarf B stars in short-period binaries
astro-ph.SRS. D. Kawaler, M. D. Reed, R. H. Østensen, S. Bloemen
The survey phase of the Kepler Mission includes a number of hot subdwarf B (sdB) stars to search for nonradial pulsations. We present our analysis of two sdB stars that are found to be g-mode pulsators of the V1093 Her class. These two stars also display the distinct irradiation effect typical of sdB stars with a close M-dwarf companion with orbital periods
Lorenzo Bertini, Marcello Ponsiglione
Consider the viscous Burgers equation on a bounded interval with inhomogeneous Dirichlet boundary conditions. Following the variational framework introduced by Bertini-De Sole-Gabrielli-Jona-Lasinio-Landim C, we analyze a Lyapunov functional for such equation which gives the large deviations asymptotics of a stochastic interacting particles model associated
Xin-She Yang
Test functions are important to validate new optimization algorithms and to compare the performance of various algorithms. There are many test functions in the literature, but there is no standard list or set of test functions one has to follow. New optimization algorithms should be tested using at least a subset of functions with diverse properties so as to
Kanglin Chen, Dirk A. Lorenz
The problem of the generation of an intermediate image between two given images in an image sequence is considered. The problem is formulated as an optimal control problem governed by a transport equation. This approach bears similarities with the Horn \& Schunck method for optical flow calculation but in fact the model is quite different. The images are mod
A. V. Kotikov, V. G. Krivokhizhin, B. G. Shaikhatdenov
Deep inelastic scattering data on the F_2 structure function provided by the BCDMS, SLAC and NMC collaborations are analyzed in the non-singlet approximation with the analytic and "frozen" modifications of the strong coupling constant featuring no unphysical singularity (the Landau pole). Improvement of agreement between theory and experiment, with r
S. H. Hendi
In this paper, with considering the nonlinear electromagnetic field coupled to Einstein gravity, we obtain the higher dimensional slowly rotating charged black hole solutions. By use of the fact that the temperature of the extreme black hole is zero, we find that these solutions may be interpreted as black hole solutions with inner (Cauchy) and outer (event)
Rinaldo Baldini Ferroli, Simone Pacetti, Adriano Zallo
The Sommerfeld rescattering formula is compared to the e+e- -> ppbar BaBar data at threshold and above. While there is the expected Coulomb enhancement at threshold, two unexpected outcomes have been found: |G^p (4M_p^2)|= 1, like for a pointlike fermion, and moreover data show that the resummation factor in the Sommerfeld formula is not needed. Other e+e- -
Andreas Björklund
We present a Monte Carlo algorithm for Hamiltonicity detection in an $n$-vertex undirected graph running in $O^*(1.657^{n})$ time. To the best of our knowledge, this is the first superpolynomial improvement on the worst case runtime for the problem since the $O^*(2^n)$ bound established for TSP almost fifty years ago (Bellman 1962, Held and Karp 1962). It an
M. Stratmann, R. Sassot, P. Zurita
We present a detailed phenomenological analysis of single-inclusive hadron production at the CERN-LHC in both proton-proton and proton-lead collisions. First data from the LHC experiments on charged hadron spectra are compared to next-to-leading order QCD expectations, and predictions are made for identified pion, kaon, and proton distributions differential
German Gomez-Herrero, Wei Wu, Kalle Rutanen, Miguel C. Soriano
Finding interdependency relations between (possibly multivariate) time series provides valuable knowledge about the processes that generate the signals. Information theory sets a natural framework for non-parametric measures of several classes of statistical dependencies. However, a reliable estimation from information-theoretic functionals is hampered when
Christopher Bradley
The ten pairs of directly similar triangles in perspective in the Wood-Desargues' configuration have ten common Hagge circle centres. These centres are known to lie one each of the ten perspectrices. It is shown in this paper that these centres also lie at the vertices of five cyclic quadrangles, which are similar to the five cyclic quadrangles of the in
J. G. Kirk
The radio, optical, X-ray and gamma-ray nebulae that surround many pulsars are thought to arise from synchrotron and inverse Compton emission. The energy powering this emission, as well as the magnetic fields and relativistic particles, are supplied by a "wind" driven by the central object. The inner parts of the wind can be described using the equat
Properties of odd nuclei and the impact of time-odd mean fields: A systematic Skyrme-Hartree-Fock analysis
nucl-thK. J. Pototzky, J. Erler, P. -G. Reinhard, V. O. Nesterenko
We present a systematic analysis of the description of odd nuclei by the Skyrme-Hartree-Fock approach augmented with pairing in BCS approximation and blocking of the odd nucleon. Current and spin densities in the Skyrme functional produce time-odd mean fields (TOMF) for odd nuclei. Their effect on basic properties (binding energies, odd-even staggering, sepa
Agil Kh. Khanmamedov
We study the solution of the Toda lattice Cauchy problem with steplike initial data. The initial data are supposed to tend to zero as $n \to +\infty$. By the inverse scattering transform method formulas allowing us to find solution of the Toda lattice are obtained.
Analytic description and explicit parametrization of the equilibrium shapes of elastic rings and tubes under uniform hydrostatic pressure
math-phPeter A. Djondjorov, Vassil M. Vassilev, Ivailo M. Mladenov
The parametric equations of the plane curves determining the equilibrium shapes that a uniform inextensible elastic ring or tube could take subject to a uniform hydrostatic pressure are presented in an explicit analytic form. The determination of the equilibrium shape of such a structure corresponding to a given pressure is reduced to the solution of two tra
David Gerard-Varet, Toan Nguyen
In the lines of a recent paper by Gerard-Varet and Dormy, we establish various ill-posedness results for the Prandtl equation. By considering perturbations of stationary shear flows, we show that for some linearizations of the Prandtl equation and some $C^\infty$ initial data, local in time $C^\infty$ solutions do not exist. At the nonlinear level, we prove
Balázs Dóra, Roderich Moessner
A single two-dimensional Dirac cone with a mass gap produces a quantized (spin-) Hall step in the absence of magnetic field. What happens in strong electric fields? This question is investigated by analyzing time evolution and dynamics of the (spin-) Hall effect. After switching on a longitudinal electric field, a stationary Hall current is reached through d
Strategy iteration is strongly polynomial for 2-player turn-based stochastic games with a constant discount factor
cs.GTThomas Dueholm Hansen, Peter Bro Miltersen, Uri Zwick
Ye showed recently that the simplex method with Dantzig pivoting rule, as well as Howard's policy iteration algorithm, solve discounted Markov decision processes (MDPs), with a constant discount factor, in strongly polynomial time. More precisely, Ye showed that both algorithms terminate after at most $O(\frac{mn}{1-γ}\log(\frac{n}{1-γ}))$ iterations, wh
Paired phases and Bose-Einstein condensation of spin-one bosons with attractive interaction
cond-mat.quant-gasG. Pelka, K. Byczuk, J. Tworzydlo
We analyze paired phases of cold bosonic atoms with the hyper spin S=1 and with an attractive interaction. We derive mean-field self-consistent equations for the matrix order parameter describing such paired bosons on an optical lattice. The possible solutions are classified according to their symmetries. In particular, we find that the self-consistent equat
Bounded Coordinate-Descent for Biological Sequence Classification in High Dimensional Predictor Space
cs.LGGeorgiana Ifrim, Carsten Wiuf
We present a framework for discriminative sequence classification where the learner works directly in the high dimensional predictor space of all subsequences in the training set. This is possible by employing a new coordinate-descent algorithm coupled with bounding the magnitude of the gradient for selecting discriminative subsequences fast. We characterize
Ilse Fischer
In recent papers we have studied refined enumerations of alternating sign matrices with respect to a fixed set of top and bottom rows. The present paper is a first step towards extending these considerations to alternating sign matrices where in addition a number of left and right columns are fixed. The main result is a simple linear relation between the num
Dror Sagi, Tsvi Tlusty, Joel Stavans
Homologous recombination plays a key role in generating genetic diversity, while maintaining protein functionality. The mechanisms by which RecA enables a single-stranded segment of DNA to recognize a homologous tract within a whole genome are poorly understood. The scale by which homology recognition takes place is of a few tens of base pairs, after which t
Simone A. Hamerla, Sebastian Duffe, Götz S. Uhrig
Mapping complex problems to simpler effective models is a key tool in theoretical physics. One important example in the realm of strongly correlated fermionic systems is the mapping of the Hubbard model to a t-J model which is appropriate for the treatment of doped Mott insulators. Charge fluctuations across the charge gap are eliminated. So far the derivati
Jan Holland
We prove that $D\geq 5$ dimensional stationary, non-static near horizon geometries with (D-3) rotational symmetries subject to the vacuum Einstein equations including a cosmological constant cannot have toroidal horizon topology. In D=4 dimensions the same result is obtained under the assumption of a non-negative cosmological constant.
Jean-François Burnol
Let $H$ be a Hilbert space of entire functions. Let $H'$ be the space of the functions $f(z)/\prod_i(z-z_i)$ where $f$ belongs to $H$ and vanishes at $n$ given complex points $z_i$. We compute a suitable $E$ function for $H'$ when one is given for $H$.
E. Khomenko, V. Martinez Pillet, S. K. Solanki, J. C. del Toro Iniesta
Based on IMaX/Sunrise data, we report on a previously undetected phenomenon in solar granulation. We show that in a very narrow region separating granules and intergranular lanes the spectral line width of the Fe I 5250.2 A line becomes extremely small. We offer an explanation of this observation with the help of magneto-convection simulations. These regions
Y. Matsuoka, S. Masaki, K. Kawara, N. Sugiyama
We present a clustering analysis of ~60,000 massive (stellar mass Mstar > 10^{11} Msun) galaxies out to z = 1 drawn from 55.2 deg2 of the UKIRT Infrared Deep Sky Survey (UKIDSS) and the Sloan Digital Sky Survey (SDSS) II Supernova Survey. Strong clustering is detected for all the subsamples of massive galaxies characterized by different stellar masses (Mstar
Niamh O'Sullivan
The study of localizations of groups has concentrated on group theoretic properties which are preserved by localization. In this paper we look at finitely generated soluble groups and determine when the local groups associated with them are soluble.
Peter Friz, Harald Oberhauser
This article introduces the splitting method to systems responding to rough paths as external stimuli. The focus is on nonlinear partial differential equations with rough noise but we also cover rough differential equations. Applications to stochastic partial differential equations arising in control theory and nonlinear filtering are given.
Markus C. Kohler, Michael Klaiber, Karen Z. Hatsagortsyan, Christoph H. Keitel
High-order harmonic generation (HHG) with relativistically strong laser pulses is considered employing electron ionization-recollisions from multiply charged ions in counterpropagating, linearly polarized attosecond pulse trains. The propagation of the harmonics through the medium and the scaling of HHG into the multi-kilo-electronvolt regime are investigate
Masataka Fukugita, Naoki Yasuda, Mamoru Doi, James E. Gunn
We study the photometric properties of stars in the data archive of the Sloan Digital Sky Survey (SDSS), the prime aim being to understand the photometric calibration over the entire data set. It is confirmed that the photometric calibration for point sources has been made overall tightly against the SDSS standard stars. We have also confirmed that photometr
D. J. Hepburn, G. J. Ackland, P. Olsson
We present empirical potentials for dilute transition metal solutes in a-iron. It is in the Finnis-Sinclair form and is therefore suitable for billion atom molecular dynamics simulations. First principles calculation shows that there are clear trends across the transition metal series which enable us to relate the rescaling parameters to principal quantum nu
V. V. Bludov, A. M. W. Glass
We construct a finitely presented (two-sided) totally orderable group with insoluble word problem.
Marco Regis
Although well established observations on cosmological, cluster, and galactic scales strongly suggest the existence of dark matter (DM), our understanding of its non-gravitational properties is still lacking. I review basic aspects of particle dark matter and detection strategies, outlining the state of the art for searches in direct detection experiments, i
Ram Band, Gregory Berkolaiko, Uzy Smilansky
We investigate the properties of the zeros of the eigenfunctions on quantum graphs (metric graphs with a Schrödinger-type differential operator). Using tools such as scattering approach and eigenvalue interlacing inequalities we derive several formulas relating the number of the zeros of the n-th eigenfunction to the spectrum of the graph and of some of its
Li-Gang Wang, Xi Chen
In this paper, the electronic band structures and its transport properties in the gapped graphene superlattices, with one-dimensional (1D) periodic potentials of square barriers, are systematically investigated. It is found that a zero averaged wave-number (zero-$\overline{k}$ ) gap is formed inside the gapped graphene-based superlattices, and the condition
Sergei V. Shabanov, Igor B. Gornushkin
An emission tomography of laser-induced plasmas employed in the laser induced breakdown spectroscopy (LIBS) requires long signal integration times during which the plasma cannot be considered stationary. To reduce the integration time, it is proposed to measure a plasma absorption in parallel rays with an aperture that collects light coming from large fracti
Benjamin Doerr, Mahmoud Fouz
We give a time-randomness tradeoff for the quasi-random rumor spreading protocol proposed by Doerr, Friedrich and Sauerwald [SODA 2008] on complete graphs. In this protocol, the goal is to spread a piece of information originating from one vertex throughout the network. Each vertex is assumed to have a (cyclic) list of its neighbors. Once a vertex is informe
Amelia Carolina Sparavigna
The paper is proposing a survey of a region in Sudan, the Bayuda desert, using the satellite images as obtained from Google Maps. The images reveal the ring granitic structure of the region enclosed by a bend of river Nile. To enhance the features of the landform, images are processed with a method based on fractional calculus, able to increase the rendering
P. M. Gauthier, N. Tarkhanov
We show that it is possible to approximate the zeta-function of a curve over a finite field by meromorphic functions which satisfy the same functional equation and moreover satisfy (respectively do not satisfy) the analogue of the Riemann hypothesis. In the other direction, it is possible to approximate holomorphic functions by simple manipulations of such a
Universal behavior of the gluon saturation scale at high energy including full NLL BFKL effects
hep-phGuillaume Beuf
The universal traveling wave solution to the Balitsky-Kovchegov equation with running coupling (and other equations in the same universality class) is extended to subleading orders at large rapidity and small dipole size $r$. The large rapidity expansion of the logarithm of the saturation scale $Q_s(Y)$ is derived from that traveling wave solution. In additi
J. Ballot
CoRoT has allowed a quantitative leap for the solar-like-star seismology thanks to 5-month-long uninterrupted timeseries of high-precision photometric data. Kepler is also starting to deliver similar data. Now, several F and G main-sequence stars have been analyzed. The techniques developed to interpret light curves directly inherit from the experience got o
Karol Trojanowski, Lech Longa
By means of numerical integration we investigate the coherent and incoherent phases in a generalized Kuramoto model of phase-coupled oscillators with distance-dependent delay. Preserving the topology of a complete graph, we arrange the nodes on a square lattice while introducing finite interaction velocity, which gives rise to non-uniform delay. It is found
E. A. Yanovich
In this paper we construct the new coefficient which allows to measure quantitatively the independence of the two discrete random variables. The new inequalities for the matrices with non-negative elements are found
Lee Chee Kong
This thesis covers various aspects of open systems in classical and quantum mechanics. In the first part, we deal with classical systems. The bath-of-oscillators formalism is used to describe an open system, and the phenomenological Langevin equation is recovered. The Fokker-Planck equation is derived from its corresponding Langevin equation. The Fokker-Plan
Lorenzo Mazzieri, Antonio Segatti
In this paper we produce families of complete non compact Riemannian metrics with positive constant $σ_k$-curvature by performing the connected sum of a finite number of given $n$-dimensional Delaunay type solutions, provided $2 \leq 2k < n$. The problem is equivalent to solve a second order fully nonlinear elliptic equation.
Dynamical Behaviours of the Nonlinear Atom-Field Interaction in the Presence of Classical Gravity: f-Deformation Approach
quant-phSh. Barzanjeh1, M. H. Naderi, M. Soltanolkotabi
In this paper, we investigate the effects of a classical gravitational field on the dynamical behaviour of nonlinear atom-field interaction within the framework of the f-deformed Jaynes-Cummings model. For this purpose, we first introduce a set of new atomic operators obeying an f-deformed su(2) algebraic structure to derive an effective Hamiltonian for the
Young-Hwan Hyun, Yoonbai Kim, Corneliu Sochichiu, Min-Young Choi
We consider graphene bilayer in a constant magnetic field of arbitrary orientation (i.e. tilted with respect to the graphene plane). In the low energy approximation to tight binding model with Peierls substitution, we find the exact spectrum of Landau levels. This spectrum is two-fold degenerate in the limit of large in-plane field, which gives rise to a new
Cosmological birefringence due to CPT-even Chern-Simons-like term with Kalb-Ramond and scalar fields
hep-phShih-Hao Ho, W. F. Kao, Kazuharu Bamba, C. Q. Geng
We study the CPT-even dimension-six Chern-Simons-like term by including dynamical Kalb-Ramond and scalar fields to examine the cosmological birefringence. We show that the combined effect of neutrino current and Kalb-Ramond field could induce a sizable rotation polarization angle in the cosmic microwave background radiation polarization.
Frank Aurzada, Steffen Dereich
We consider the one-sided exit problem for (fractionally) integrated random walks and Lévy processes. We prove that the rate of decrease of the non-exit probability -- the so-called survival exponent -- is universal in this class of processes. In particular, the survival exponent can be inferred from the (fractionally) integrated Brownian motion. This, in pa
Diego F. Torres
The gamma-ray binaries LS 5039 and LS I +61 303 have been detected by Cerenkov telescopes at TeV energies, exhibiting periodic behavior correlated with the orbital period. These gamma-ray binary systems have also been recently detected by the Fermi Gamma-ray Telescope at GeV energies, and combination of GeV and TeV observations are providing both, expected a
Colin Wilkin
New experimental data are presented on the energy dependence of the total cross sections for the np -> d eta and quasi-two-body pp -> pp eta reactions, where the final diproton is detected at very low excitation energy. Differential cross sections of pp -> pp eta away from threshold show the influence of higher partial waves and a partial wave decomposition
Shijun Mao, Yoshio Kuramoto, Ken-Ichiro Imura, Ai Yamakage
Spectrum and wave function of gapless edge modes are derived analytically for a tight-binding model of topological insulators on square lattice. Particular attention is paid to dependence on edge geometries such as the straight (1,0) and zigzag (1,1) edges in the thermodynamic limit. The key technique is to identify operators that combine to annihilate the e
Forward dijets in high-energy collisions: evolution of QCD n-point functions beyond the dipole approximation
hep-phAdrian Dumitru, Jamal Jalilian-Marian
Present knowledge of QCD n-point functions of Wilson lines at high energies is rather limited. In practical applications, it is therefore customary to factorize higher n-point functions into products of two-point functions (dipoles) which satisfy the BK evolution equation. We employ the JIMWLK formalism to derive explicit evolution equations for the 4- and 6
Colin Wilkin
The roles of the COSY-TOF and COSY-ANKE spectrometers in the measurement of strange meson production are briefly reviewed, mainly in connection with new results on the pp -> K^+ p Lambda, pp -> K^+ p Sigma^0 and pp -> K^+ n Sigma^+ reactions.
Péter Veres, Zsolt Bagoly
With the early afterglow localizations of gamma-ray burst positions made by Swift, the clear delimitation of the prompt phase and the afterglow is not so obvious any more. It is important to see weather the two phases have the same origin or they stem from different parts of the progenitor system. We will combine the two kinds of gamma-ray burst data from th
N. Aoi, S. Kanno, S. Takeuchi, H. Suzuki
The neutron-rich nucleus 74Ni was studied with inverse-kinematics inelastic proton scattering using a 74Ni radioactive beam incident on a liquid hydrogen targetat a center-of-mass energy of 80 MeV. From the measured de-excitation gamma-rays, the population of the first 2+ state was quantified. The angle-integrated excitation cross section was determined to b
M. A. Jafarizadeh, N. Behzadi, Y. Akbari
On the basis of linear programming, new sets of entanglement witnesses (EWs) for 3x3 and 4x4 systems are constructed. In both cases, the constructed EWs correspond to the hyperplanes contacting, without intersecting, the related feasible regions at line segments and restricted planes respectively. Due to the special property of the contacting area between th
Satoshi Yashiki, Shunsuke Kirino, Kazuo Ueda
A generalized Anderson model for a magnetic ion in a harmonic potential is formulated. The model is investigated by the numerical renormalization group(NRG) method. In addition to the conventional s-wave screening, the model exhibits phonon assisted p-wave Kondo effect as well as Yu and Anderson type Kondo effect. It is shown that the s-wave Kondo and the Yu
Stefan A. Revets
The determination of confidence intervals of stress orientation is a crucial element in the discussion of homogeneity or heterogeneity of the stress field under study. The error estimates provided by the grid search method Focal Mechanism Stress Inversion of Gephart and Forsyth (1984) have been shown to be too wide but the reasons for this failure have escap
Yuki Kanai, Masaru Siino, Akio Hosoya
We construct an exact solution for the spherical gravitational collapse in a single coordinate patch. To describe the dynamics of collapse, we use a generalized form of the Painlevé-Gullstrand coordinates in the Schwarzschild spacetime. The time coordinate of the form is the proper time of a free-falling observer so that we can describe the collapsing star n