October 2010 arXiv papers — page 6

V. Kotimaki, E. Cicek, A. Siddiki, E. Rasanen

A numerical approach is employed to explain transport characteristics in realistic, quantum Hall based Aharonov-Bohm interferometers. First, the spatial distribution of incompressible strips, and thus the current channels, are obtained applying a self-consistent Thomas-Fermi method to a realistic heterostructure under quantized Hall conditions. Second, the t

Piero Rosati, Stefano Borgani, Roberto Gilli, Maurizio Paolillo

We list here the contents of the Proceedings of the "Wide Field X-ray Telescope" conference held in Bologna, Italy on 25-26 Nov 2009. The conference highlighted the scientific potential and discovery space provided by an X-ray mission concept characterized by a wide field-of-view (1 sq.deg.), large effective area (1 sq.mt.) and approximately constant

A. D. Giddings, J. G. Keizer, M. Hara, G. J. Hamhuis

This study compares cross-sectional scanning tunnelling microscopy (XSTM) and atom probe tomography (APT). We use epitaxially grown self-assembled InAs quantum dots (QDs) in GaAs as an exemplary material with which to compare these two nanostructural analysis techniques. We studied the composition of the wetting layer and the QDs, and performed quantitative

Gregory Gutin, Mark Jones, Anders Yeo

In the {\sc Hitting Set} problem, we are given a collection $\cal F$ of subsets of a ground set $V$ and an integer $p$, and asked whether $V$ has a $p$-element subset that intersects each set in $\cal F$. We consider two parameterizations of {\sc Hitting Set} below tight upper bounds: $p=m-k$ and $p=n-k$. In both cases $k$ is the parameter. We prove that the

Se-Wan Ji, Jaewan Kim, Hai-Woong Lee, M. S. Zubairy

In a recent note, Cavalcanti and Scarani (CS) constructed a counter local-hidden-variable model to explain the violation of our inequalities in Phys. Rev. Lett. 105, 170404 (2010). Here, we briefly discuss some issues in response to the comments raised by CS.

Tristan Dennen, Yu-tin Huang

We demonstrate that the tree-level amplitudes of maximal super-Yang-Mills theory in six dimensions, when stripped of their overall momentum and supermomentum delta functions, are covariant with respect to the six-dimensional dual conformal group. Using the generalized unitarity method, we demonstrate that this property is also present for loop amplitudes. Si

Baishali Chakraborty, Kumar S. Gupta, Siddhartha Sen

We show that the critical charge for the Dirac excitations in gapless graphene depends on the spatial topology of the sample. In particular, for graphene cones, the effective value of the critical charge can tend towards zero for a suitable angle of the conical sample. We discuss the nature of the scattering phase shifts, quasi-bound state energies and local

Liang Jiang, Charles L. Kane, John Preskill

We propose and analyze an interface between a topological qubit and a superconducting flux qubit. In our scheme, the interaction between Majorana fermions in a topological insulator is coherently controlled by a superconducting phase that depends on the quantum state of the flux qubit. A controlled phase gate, achieved by pulsing this interaction on and off,

Ezra Getzler

We show that there is a sequence of operations on the positively graded part of a differential graded algebra making it into an L-infinity algebra. The formulas for the higher brackets involve Bernoulli numbers. The construction generalizes the derived bracket for Poisson manifolds, and the Lie 2-algebra associated to a Courant algebroid constructed by Royte

Shahrukh Khalid, Adnan Ali Khan

A number of data acquisition systems depend on human interface to access computer for measuring, processing and analyzing data and to prepare it for presentation and storage. Data acquisition software is installed on the computer and all intended operations are performed manually. The data acquisition software requires user intervention for operations like s

Fabrice Baudoin, Alice Vatamanelu

We study new heat kernel estimates for the Neumann heat kernel on a compact manifold with positive Ricci curvature and convex boundary. As a consequence, we obtain new lower bounds for the Neumann eigenvalues which are consistent with Weyl's asymptotics.

Y. H. Kim, Xuandong Zhao, Günter Schmid

We have carried out far-infrared (far-IR) transmission measurements on the ligand stabilized Au55 nanoparticles dispersed in Teflon at volume fractions ranging from 0.2% to 1%. Instead of a series of peaks which might arise from the electron transition between discrete energy levels, we have observed a broad far-IR absorption coefficient that follows with an

Bo Zhu, Pietro Govoni, Yajun Mao, Chiara Mariotti

WW scattering is an important process to study electroweak symmetry breaking in the Standard Model at the LHC, in which the Higgs mechanism or other new physics processes must intervene to preserve the unitarity of the process below 1 TeV. This channel is expected to be one of the most sensitive to determine whether the Higgs boson exists. In this paper, the

Hau-wen Huang

A configuration of the lit-only $σ$-game on a finite graph $Γ$ is an assignment of one of two states, on or off, to all vertices of $Γ.$ Given a configuration, a move of the lit-only $σ$-game on $Γ$ allows the player to choose an on vertex $s$ of $Γ$ and change the states of all neighbors of $s.$ Given any integer $k$, we say that $Γ$ is $k$-lit if, for any

Tomohiro Taniguchi, Hiroshi Imamura

We studied the magnetization reversal rates of thermally assisted spin transfer torque switching in a ferromagnetically coupled synthetic free layer theoretically. By solving the Fokker-Planck equation, we obtained the analytical expression of the switching probability for both the weak and the strong coupling limit. We found that the thermal stability is pr

Ariel Edery, Benjamin Constantineau

We show that extremal black holes have zero entropy by pointing out a simple fact: they are time-independent throughout the spacetime and correspond to a single classical microstate. We show that non-extremal black holes, including the Schwarzschild black hole, contain a region hidden behind the event horizon where all their Killing vectors are spacelike. Th

Man-Duen Choi, Frederic Latremoliere

We investigate the structure of the automorphism of $\mathcal{O}_{2}$ which exchanges the two canonical isometries. Our main observation is that the fixed point C*-subalgebra for this action is isomorphic to $\mathcal{O}_{2}$ and we detail the relationship between the crossed-product and fixed point subalgebra.

Tadashi Machida, Takuya Kato, Hiroshi Nakamura, Masaki Fujimoto

Using Scanning tunneling spectroscopy (STS), we report the correlation between spatial gap inhomogeneity and the zinc (Zn) impurity resonance in single crystals of Bi$_{\mathrm{2}}$Sr$_{\mathrm{2}}$Ca(Cu$_{\mathrm{1-}x}$Zn$_{x}$)$_{\mathrm{2}}$O$_{\mathrm{8+}δ}$ with different carrier (hole) concentrations ($p$) at a fixed Zn concentration ($x$ $\sim$ 0.5 %

Daniel Miller

This is an expository work presenting in detail the proof of the structure theorem for divisible abelian groups. A divisible abelian group is an abelian group that satisfies nD=D for all natural n. The theorem states that any divisible group is a direct sum of copies of the additive rationals and quasicyclic groups.

Toshiyuki Katsura, Shigeyuki Kondo

We construct, on a supersingular K3 surface with Artin invariant 1 in characteristic 2, a set of 21 disjoint smooth rational curves and another set of 21 disjoint smooth rational curves such that each curve in one set intersects exactly 5 curves from the other set with multiplicity 1 by using the structure of a generalized Kummer surface.

Yu Kawasaki, Jorge L. Gavilano, Lukas Keller, Jurg Schefer

We report a neutron diffraction and muon spin relaxation muSR study of static and dynamical magnetic properties of BaCo2V2O8, a quasi-one-dimensional spin-chain system. A proposed model for the antiferromagnetic structure includes: a propagation vector k_AF = (0, 0, 1), independent of external magnetic fields for fields below a critical value H_c(T). The ord

A. Pinzul

We initiate the study of Horava-Lifshitz models of gravity in the framework of spectral geometry. As the first step, we calculate the dimension of space-time. It is shown, that for the natural choice of a Dirac operator (or rather corresponding generalized Laplacian), which respects both the foliation structure and anisotropic scaling, the result of Horava o

Yu-Fang Chen, Ahmed Rezine

The aim of the INFINITY workshop is to provide a forum for researchers interested in the development of formal methods and algorithmic techniques for the analysis of systems with infinitely many states, and their application in automated verification of complex software and hardware systems.

A. Moreno-Gobbi, G. Zamir, J. A. Eiras

In this paper we present experimental data of ultrasonic velocity and attenuation obtained in a high purity crystalline sample of cooper hydrogenated by gaseous charge. The sample is oriented in the <111> crystallographic direction and aged for this work in three stages between 64 and 97 days. The results indicate that the hydrogen is mainly segregated at th

Roland Kothes, Tom L. Landecker, Andrew D. Gray

The DRAO ST was used for the past 15 years as the primary instrument for the Canadian Galactic Plane Survey. This has been a spectacularly successful project, advancing our understanding of the Milky Way Galaxy through panoramic imaging of the main constituents of the Interstellar Medium. Observations for the CGPS are now complete and the Synthesis Telescope

Kevin Hayden, Eric Olson, Edriss S. Titi

Consider a continuous dynamical system for which partial information about its current state is observed at a sequence of discrete times. Discrete data assimilation inserts these observational measurements of the reference dynamical system into an approximate solution by means of an impulsive forcing. In this way the approximating solution is coupled to the

Brian Macdonald

We study the density of complex critical points of a real random SO(m+1) polynomial in m variables. In a previous paper [Mac09], the author used the Poincare- Lelong formula to show that the density of complex zeros of a system of these real random polynomials rapidly approaches the density of complex zeros of a system of the corresponding complex random pol

Enrique Perez-Montero, Monica Relano, Jose M. Vilchez, Ana Monreal-Ibero

We present a set of photoionization models that reproduce simultaneously the observed optical and mid-infrared spatial distribution of the HII region NGC595 in the disk of M33 using the code CLOUDY. Both optical (PMAS-Integral Field Spectroscopy) and mid-infrared (8 mi and 24 mi bands from Spitzer) data provide enough spatial resolution to model in a novel a

Biagio Lucini, Antonio Rago, Enrico Rinaldi

The lowest-lying glueball masses are computed in SU($N$) gauge theory on a spacetime lattice for constant value of the lattice spacing $a$ and for $N$ ranging from 3 to 8. The lattice spacing is fixed using the deconfinement temperature at temporal extension of the lattice $N_T = 6$. The calculation is conducted employing in each channel a variational ansatz

P. A. Cargile, D. J. James, R. D. Jeffries

We present results from a spectroscopic study of the very low mass members of the Southern open cluster Blanco 1 using the Gemini-N telescope. We obtained intermediate resolution (R~4400) GMOS spectra for 15 cluster candidate members with I~14-20 mag, and employed a series of membership criteria - proximity to the cluster&#39;s sequence in an I/I-Ks color-ma

Chung Chiang Wu, Zhaohui Zhong

We report the capacitive spring softening effect observed in single-walled carbon nanotube (SWNT) nanoelectromechanical (NEM) resonators. The nanotube resonators adopt dual-gate configuration with both bottom-gate and side-gate capable of tuning the resonance frequency through capacitive coupling. Interestingly, downward resonance frequency shifting is obser

A. Tawfik, A. Saleh, M. T. Ghoneim, A. Hady

Based on the generic acceleration model, which suggests different types of electromagnetic interactions between the cosmic charged particles and the different configurations of the electromagnetic (plasma) fields, the ultra high energy cosmic rays are studied. The plasma fields are assumed to vary, spatially and temporally. The well-known Fermi accelerations

Brian R. Kent

Aperture synthesis observations of two HI cloud complexes located in the periphery of the Virgo galaxy cluster are presented. These low HI-mass clouds ($M_{HI}<$ 10$^{9}$) are seen projected on the M region of the western Virgo cluster, where the galaxy population is thought to lie behind the main A cluster surrounding M87. The kinematic measurements of both

Thomas J. Maccarone, Brian Warner

The globular cluster X-ray source CXO J033831.8-352604 in NGC 1399 has recently been found to show strong emission lines of [O III] and [N II] in its optical spectrum in addition to ultraluminous X-ray emission with a soft X-ray spectrum. It was further suggested that this system contained an intermediate mass black hole which had tidally disrupted a white d

Michael P. Allocca, Tom Lada

We construct an example of an $A_{\infty}$ algebra structure defined over a finite dimensional graded vector space.

Nikolai Nikolski, Vasily Vasyunin

For a given $δ$, $0<δ<1$, a Blaschke sequence $σ=\{λ_j\}$ is constructed such that every function $f$, $f\in H^\infty$, having $δ<δ_f=\inf_{λ\inσ}|f(λ)|\le\|f\|_\infty\le1$ is invertible in the trace algebra $H^\infty|σ$ (with a norm estimate of the inverse depending on $δ_f$ only), but there exists $f$ with $δ=δ_f\le\|f\|_\infty\le1$, which does not. As an

A. M. Hidalgo-Gamez, D. Ramirez-Fuentes, J. J. Gonzalez

The oxygen abundances for four dwarf spiral galaxies have been determined using long-slit spectroscopy. The abundances of these galaxies have not previously reported in the literature. Several HII regions were detected in each galaxy. The electronic temperature method could be used only in one region because of the lack of the auroral lines of oxygen or sulf

Manas Khan, A. K. Sood

Many wormlike micellar systems exhibit appreciable shear thinning due to shear induced alignment. As the micelles get aligned introducing directionality in the system, the viscoelastic properties are no longer expected to be isotropic. An optical tweezers based active microrheology technique enables us to probe the out-of-equilibrium rheological properties o

Drew Clausen, Michael Eracleous

We calculate the emission line spectrum produced by the debris released when a white dwarf (WD) is tidally disrupted by an intermediate-mass black hole (IMBH; $M\sim 10^{2}-10^{5}\msun$) and we explore the possibility of using the emission lines to identify such events and constrain the properties of the IMBH. To this end, we adopt and adapt the techniques d

Aaron M. Katzenmeyer, François Léonard, A. Alec Talin, Ping-Show Wong

We present electronic transport measurements of GaAs nanowires grown by catalyst-free metal-organic chemical vapor deposition. Despite the nanowires being doped with a relatively high concentration of substitutional impurities, we find them inordinately resistive. By measuring sufficiently high aspect-ratio nanowires individually in situ, we decouple the rol

Eric Vernier, David Pekker, Martin W. Zwierlein, Eugene Demler

We consider a localized impurity atom that interacts with a cloud of fermions in the paired state. We develop an effective scattering length description of the interaction between an impurity and a fermionic atom using their vacuum scattering length. Treating the pairing of fermions at the mean-field level, we show that the impurity atom acts like a magnetic

Bernhelm Booss-Bavnbek

We explain an array of basic functional analysis puzzles on the way to general spectral flow formulae and indicate a direction of future topological research for dealing with these puzzles.

Milan Perkovac

Using Pearson correlation coefficient a statistical analysis of Duane-Hunt and Kulenkampff&#39;s measurement results was performed. This analysis reveals that empirically based Duane-Hunt&#39;s law is not entirely consistent with the measurement data. The author has theoretically found the action of electromagnetic oscillators, which corresponds to Planck&#3

Jean-François Burnol

We evaluate the determinant D = det((y_j u_i - x_j v_i)/(l_j - k_i)) as a function of the last sextuple (u,v,k;x,y,l), the result being shown to have a form reproducing the one of the entries of D. ----- Nous calculons le déterminant D = det((y_j u_i - x_j v_i)/(l_j - k_i)) comme fonction du dernier des sextuplets (u,v,k;x,y,l), en exprimant le résultat sous

S. Wiedmann, G. M. Gusev, O. E. Raichev, A. K. Bakarov

Experimental studies of magnetoresistance in high-mobility wide quantum wells reveal oscillations which appear with an increase in temperature to 10 K and whose period is close to that of Shubnikov-de Haas oscillations. The observed phenomenon is identified as magnetointersubband oscillations caused by the scattering of electrons between two occupied subband

Mikhail N. Smolyakov

We discuss a new solution, admitting the existence of dS_{4} branes, in five-dimensional Brans-Dicke theory. It is shown that, due to a special form of a bulk scalar field potential, for certain values of the model parameters the effective cosmological constant can be made small on the brane, where the hierarchy problem of gravitational interaction is solved

Tahir Yaqoob, Kendrah D. Murphy

Heavily obscured active galactic nuclei (AGNs) play an important role in contributing to the cosmic X-ray background (CXRB). However, the AGNs found in deep X-ray surveys are often too weak to allow direct measurement of the column density of obscuring matter. One method adopted in recent years to identify heavily obscured, Compton-thick AGNs under such circ

Matthew J. Turk, Michael L. Norman, Tom Abel

We report on simulations of the formation of the first stars in the Universe, where we identify regions of hot atomic gas (fH2 < 10-6) at densities above 10-14 g/cc, heated to temperatures ranging between 3000 and 8000 K. Within this temperature range atomic hydrogen is unable to cool effectively. We describe the kinetic and thermal characteristics of these

James T. Liu, Ruben Minasian

Stringy corrections in AdS/CFT generally fall into the category of either α&#39; effects or string loop effects, corresponding to 1/λand 1/N corrections, respectively, in the dual field theory. While α&#39;^3R^4 corrections have been well studied, at least in the context of N=4 super-Yang-Mills, less is known about the 1/N^2 corrections arising from closed s

Nicholas J. Nelson, Benjamin P. Brown, Matthew K. Browning, Allan Sacha Brun

Observations of sun-like stars rotating faster than our current sun tend to exhibit increased magnetic activity as well as magnetic cycles spanning multiple years. Using global simulations in spherical shells to study the coupling of large-scale convection, rotation, and magnetism in a younger sun, we have probed effects of rotation on stellar dynamos and th

Sinisa Coh, David Vanderbilt, Andrei Malashevich, Ivo Souza

We present a Wannier-based method to calculate the Chern-Simons orbital magnetoelectric coupling in the framework of first-principles density-functional theory. In view of recent developments in connection with strong Z2 topological insulators, we anticipate that the Chern-Simons contribution to the magnetoelectric coupling could, in special cases, be as lar

Jiangang Hao, James Annis

Galaxy clusters are spectacular. We provide a Google Earth compatible imagery for the deep co-added images from the Sloan Digital Sky Survey and make it a tool for examing galaxy clusters. More details about how to get it can be found from the following website: https://sites.google.com/site/geclusters/

Miljan Brakočević

We prove non-vanishing modulo p, for a prime $\ell$ different from p, of central critical Rankin-Selberg L-values with anticyclotomic twists of $\ell$-power conductor. The L-function is Rankin product of a cusp form and a theta series of arithmetic Hecke character of an imaginary quadratic field. The paper is concerned with the case when the weight of Hecke

A. A. Saharian

We consider the quantum radiation of scalar particles from a surface wave excited on a plane surface of a mirror. It is assumed that the field obeys Dirichlet condition on the boundary of the mirror. In both cases of running and standing surface waves the expression is given for the spectral-angular distribution of the number of the radiated quanta.

D. Gamermann, C. García-Recio, J. Nieves, L. L. Salcedo

We follow a model based on the SU(8) symmetry for the interaction of mesons with baryons. The model treats on an equal footing the pseudo-scalars and the vector mesons, as required by heavy quark symmetry. The T-matrix calculated within an unitary scheme in coupled channels has poles which are interpreted as baryonic resonances.

S. ter Veen, S. Buitink, H. Falcke, C. W. James

A particle cascade (shower) in a dielectric, for example as initiated by an ultra-high energy cosmic ray, will have an excess of electrons which will emit coherent Čerenkov radiation, known as the Askaryan effect. In this work we study the case in which such a particle shower occurs in a medium just below its surface. We show, for the first time, that the ra

Raef Bassily, Sennur Ulukus

In this paper, we introduce two new achievable schemes for the fading multiple access wiretap channel (MAC-WT). In the model that we consider, we assume that perfect knowledge of the state of all channels is available at all the nodes in a causal fashion. Our schemes use this knowledge together with the time varying nature of the channel model to align the i

Alvaro Bustinduy

We prove that if a polynomial vector field on C2 has a proper and non-algebraic trajectory analytically isomorphic to C* all its trajectories are proper, and except at most one which is contained in an algebraic curve of type C all of them are of type C*. As corollary we obtain an analytic version of Lin-Zaidenberg Theorem for polynomial foliations.

Biagio Lucini, Gregory Moraitis, Agostino Patella, Antonio Rago

A numerical study of Orientifold Planar Equivalence is performed in SU(N) Yang-Mills theories for N=2,3,4,6. Quenched meson masses are extracted in the antisymmetric, symmetric and adjoint representations for the pseudoscalar and vector channels. An extrapolation of the vector mass as a function of the pseudoscalar mass to the large-N limit shows that the nu

Olga Katkova, Boris Shapiro, Anna Vishnyakova

In this note we prove a new result about (finite) multiplier sequences, i.e. linear operators acting diagonally in the standard monomial basis of R[x] and sending polynomials with all real roots to polynomials with all real roots. Namely, we show that any such operator does not decrease the logarithmic mesh when acting on an arbitrary polynomial having all r

Anca Gheorghiu, Anda Gheorghiu

After September 2008, the advanced economies severe decline caused demand for emerging economies&#39; exports to drop and the crisis became truly global, much deeper and broader than expected. In these times of global depression, most countries and companies are affected, some more than others. The financial crisis has turned out to be much deeper and broade

Rustam Baladai

Khabibullin&#39;s conjecture has three statements equivalent to each other. Recently Ruslan Sharipov has constructed a counterexample to this conjecture for one of its three statements. In this paper Sharipov&#39;s counterexample is transferred to the other two statements of Khabibullin&#39;s conjecture.

A. C. Bartnik, Al. L. Efros, W. -K. Koh, C. B. Murray

A theory of the electronic structure and excitonic absorption spectra of PbS and PbSe nanowires and nanorods in the framework of a four-band effective mass model is presented. Calculations conducted for PbSe show that dielectric contrast dramatically strengthens the exciton binding in narrow nanowires and nanorods. However, the self-interaction energies of t

J. E. Sonier, W. Huang, C. V. Kaiser, C. Cochrane

It is shown that attempts to accurately deduce the magnetic penetration depth of overdoped BaFe_{1.82}Co_{0.18}As2 single crystals by transverse-field muon spin rotation (TF-muSR) are thwarted by field-induced magnetic order and strong vortex-lattice disorder. We explain how substantial deviations from the magnetic field distribution of a nearly perfect vort

Arthur A. Evans, Eric Lauga

Confinement and wall effects are known to affect the kinematics and propulsive characteristics of swimming microorganisms. When a solid body is dragged through a viscous fluid at constant velocity, the presence of a wall increases fluid drag, and thus the net force required to maintain speed has to increase. In contrast, recent optical trapping experiments h

Eric G. Sorte, Boris V. Fine, Brian Saam

The transverse nuclear magnetic resonance (NMR) decays of $^{129}$Xe in polycrystalline xenon were recently shown to have a universal property: in the long-time regime these decays all converge to the same sinusoidally modulated exponential function irrespective of the initial transverse spin configuration prepared by a sequence of one or more radio frequenc

Jacob S. Levy, Mark A. Foster, Alexander L. Gaeta, Michal Lipson

The emerging field of silicon photonics seeks to unify the high bandwidth of optical communications with CMOS microelectronic circuits. Many components have been demonstrated for on-chip optical communications, including those that utilize the nonlinear optical properties of silicon[1, 2], silicon dioxide[3, 4] and silicon nitride[5, 6]. Processes such as se

Gordon J. D. Petrie, Irina Patrikeeva

Besides their own intrinsic interest, correct interpretation of solar surface magnetic field observations is crucial to our ability to describe the global magnetic structure of the solar atmosphere. Photospheric magnetograms are often used as lower boundary conditions in models of the corona, but not data from the nearly force-free chromosphere. National Sol

J. H. Cole, C. Müller, P. Bushev, G. J. Grabovskij

We use high-precision spectroscopy and detailed theoretical modelling to determine the form of the coupling between a superconducting phase qubit and a two-level defect. Fitting the experimental data with our theoretical model allows us to determine all relevant system parameters. A strong qubit-defect coupling is observed, with a nearly vanishing longitudin

Robert Szafron, Marek Zralek

The problems of neutrino production states, prepared to the oscillation process, in the case of non standard interactions, are briefly discussed. Quantum neutrino states are determined from the dynamics of a production process. We show, that even in models where only left-handed neutrinos are introduced, the standard adopted procedure is valid only approxima

Noah Linden, Sandu Popescu, Paul Skrzypczyk

We construct the smallest possible self contained heat engines; one composed of only two qubits, the other of only a single qutrit. The engines are self-contained as they do not require external sources of work and/or control. They are able to produce work which is used to continuously lift a weight. Despite the dimension of the engine being small, it is sti

Javier L Albacete

A brief review of the phenomenological studies in the field of heavy ion collisions based on the Color Glass Condensate theory and, in particular, of those relying in the use of the BK equation including running coupling effects is presented.

Delphine Lautier, Franck Raynaud

This article presents an empirical study of thirteen derivative markets for commodity and financial assets. It compares the statistical properties of futures contracts&#39;s daily returns at different maturities, from 1998 to 2010 and for delivery dates up to 120 months. The analysis of the fourth first moments of the distribution shows that the mean and var

Gregory Seregin, Luis Silvestre, Vladimir Sverak, Andrej Zlatos

We investigate the validity and failure of Liouville theorems and Harnack inequalities for parabolic and elliptic operators with low regularity coefficients. We are particularly interested in operators of the form $\partial_t - Δ+b\cdot\nabla$ and $-Δ+b\cdot\nabla$ with a divergence-free drift $b$. We prove the Liouville theorem and Harnack inequality when $

Marc Peigné

We present here some basic properties around the Poincaré exponent of a discrete group of isometries in pinched negatived curvature. We state some important results and present the main tools which are used in this domain.

Shrinivas Kudekar, Henry D. Pfister

Recently, it was observed that spatially-coupled LDPC code ensembles approach the Shannon capacity for a class of binary-input memoryless symmetric (BMS) channels. The fundamental reason for this was attributed to a &#34;threshold saturation&#34; phenomena derived by Kudekar, Richardson and Urbanke. In particular, it was shown that the belief propagation (BP

Maciej Misiorny, Irenuesz Weymann, Jozef Barnas

We study transport properties of a single-molecule magnet (SMM) weakly coupled to one nonmagnetic and one ferromagnetic lead. Using the diagrammatic technique in real time, we calculate transport in the sequential and cotunneling regimes for both ferromagnetic and antiferromagnetic exchange coupling between the molecule&#39;s LUMO level and the core spin. We

V. Bernard, M. Lage, U. -G. Meißner, A. Rusetsky

Using effective field theory methods, we discuss the extraction of the mass and width of the scalar mesons f0(980) and a0(980) from the finite-volume spectrum in lattice QCD. In particular, it is argued that the nature of these states can be studied by invoking twisted boundary conditions, as well as investigating the quark mass dependence of the spectrum.

José Villa

Using, as main tool, the convergence theorem for discrete martingales and the mean value property of harmonic functions we solve, a particular case of, Dirichlet problem.

M. Fuhrmann, N. Seehafer, G. Valori, T. Wiegelmann

Extrapolations of solar photospheric vector magnetograms into three-dimensional magnetic fields in the chromosphere and corona are usually done under the assumption that the fields are force-free. The field calculations can be improved by preprocessing the photospheric magnetograms. We compare two preprocessing methods presently in use, namely the methods of

Maciej Misiorny, Ireneusz Weymann, Jozef Barnas

We analyze the stationary spin-dependent transport through a single-molecule magnet weakly coupled to external ferromagnetic leads. Using the real-time diagrammatic technique, we calculate the sequential and cotunneling contributions to current, tunnel magnetoresistance and Fano factor in both linear and nonlinear response regimes. We show that the effects o

Megan B. Gralla, Michael D. Gladders, H. K. C. Yee, L. Felipe Barrientos

We conduct a statistical analysis of the radio source population in galaxy clusters as a function of redshift by matching radio sources from the Faint Images of the Radio Sky at Twenty-Centimeters (FIRST) catalog with 618 optically-selected galaxy clusters from the first Red-Sequence Cluster Survey (RCS1). The number of excess radio sources (above the backgr

Abraham D. Smith

For the purpose of understanding second-order scalar PDEs and their hydrodynamic integrability, we introduce G-structures that are induced on hypersurfaces of the space of symmetric matrices (interpreted as the fiber of second-order jet space) and are defined by non-degenerate scalar second-order-only (Hessian) PDEs in any number of variables. The fiber grou

Jennifer S. Balakrishnan, Amnon Besser

We describe an algorithm to compute the local component at p of the Coleman-Gross p-adic height pairing on divisors on hyperelliptic curves. As the height pairing is given in terms of a Coleman integral, we also provide new techniques to evaluate Coleman integrals of meromorphic differentials and present our algorithms as implemented in Sage.

J. R. Pelaez, G. Rios

We study the pion mass dependence of the rho(770) and f_0(600) masses and widths from one and two-loop unitarized Chiral Perturbation Theory. We show the consistency of one-loop calculations with lattice results for the M_rho, f_pi and the isospin 2 scattering length a_20.Then, we develop and apply the modified Inverse Amplitude Method formalism for two-loop

Silvere Bonnabel, Philippe Martin, Pierre Rouchon, Erwan Salaun

For linear time-invariant systems, a separation principle holds: stable observer and stable state feedback can be designed for the time-invariant system, and the combined observer and feedback will be stable. For non-linear systems, a local separation principle holds around steady-states, as the linearized system is time-invariant. This paper addresses the i

Masahito Mochizuki, Naoto Nagaosa

We show theoretically with an accurate spin Hamiltonian describing the multiferroic Mn perovskites that the application of the picosecond optical pulse with a terahertz frequency can switch the spin chirality through intensely exciting the electromagnons. There are four states with different spin chiralities, i.e. clockwise and counterclockwise ab/bc-plane s

Philipp Gerhold, Karl Jansen, Jim Kallarackal

We study the effect of a potential fourth fermion generation on the upper and lower Higgs boson mass bounds. This investigation is based on the numerical evaluation of a chirally invariant lattice Higgs-Yukawa model emulating the same Higgs-fermion coupling structure as in the Higgs sector of the electroweak Standard Model. In particular, the considered mode

Jun Ding, Yugui Yao, Leonard Kleinman

Very thick films of BiCrO$_3$ have been grown on a SrTiO$_3$ substrate, maintaining a tetragonal lattice up to thicknesses of 14,000Å. Assuming we can treat films of this thickness as bulk crystals, we first calculated the experimentally undetermined atomic positions within the unit cell with the measured lattice constant of the film, then relaxed the lattic

A. B. Mason, A. J. Norton, J. S. Clark, P. Roche

The maximum mass of a neutron star (NS) is poorly defined. Theoretical attempts to define this mass have thus far been unsuccessful. Observational results currently provide the only means of narrowing this mass range down. Eclipsing X-ray binary (XRB) pulsar systems are the only interacting binaries in which the mass of the NS may be measured directly. Only

Charles B. Thorn

We improve and update the discussion, given some years ago by my collaborators and me, of infrared divergences and Bremsstrahlung in one-loop gluon scattering probabilities in lightcone gauge. In that work, we showed that adding soft and collinear gluon radiation, satisfying simple Lorentz invariant constraints, not only cancelled all IR divergences, but res

Florian U. Bernlochner, Marek Schonherr

In this publication electroweak next-to-leading order corrections to semileptonic B-meson decays into (pseudo)scalar final states are presented. To this end, these corrections of O(alpha G_F) have been calculated in the QED-enhanced phenomenological model, incorporating the bound-state mesons as its degrees of freedom, and matched to a similar calculation on

CMS Collaboration

The first measurement of the cross section for top-quark pair production in pp collisions at the LHC at center-of-mass energy sqrt(s)= 7 TeV has been performed using 3.1 {\pm} 0.3 inverse pb of data recorded by the CMS detector. This result utilizes the final state with two isolated, highly energetic charged leptons, large missing transverse energy, and two

Iftach Sadeh

The International Linear Collider (ILC) is a proposed electron-positron collider with a center-of-mass energy of 500~GeV, and a peak luminosity of $2 \cdot 10^{34}~\mathrm{cm}^{-2}\mathrm{s}^{-1}$. The ILC will complement the Large Hadron Collider, a proton-proton accelerator, and provide precision measurements, which may help in solving some of the fundamen

R. Angstadt, W. Cooper, M. Demarteau, J. Green

A collaboration between Fermilab and the Institute for High Energy Physics (IHEP), Beijing, has developed a beam position monitor for the IHEP test beam facility. This telescope is based on 5 stations of silicon strip detectors having a pitch of 60 microns. The total active area of each layer of the detector is about 12x10 cm2. Readout of the strips is provi

Oleg Zaitsev

Semiclassical multimode laser theory is extended to gas lasers with open two-dimensional resonators of arbitrary shape. The Doppler frequency shift of the linear-gain coefficient leads to an additional linear coupling between the modes, which, however, is shown to be negligible. The nonlinear laser equations simplify in the special case of wave-chaotic reson

Ismail Zahed

Electromagnetic emission in the form of photons or dileptons provide important information on the onset and evolution of a heavy ion collision at ultrarelativistic energies. We briefly summarize the theoretical assessments of the thermalized electromagnetic emissivities from a hot partonic and hadronic medium, and compare them to current experiments at colli

J. Hammer, M. Aprili, I. Petkovic

An extended Josephson junction intrinsically couples the superconducting current to the microwave cavity in the insulating barrier. We demonstrate that this coupling produces sidebands in the microwave cavity resonances of the junction. By measuring the switching current distribution, we show that microwave radiation at sidebands brings the Josephson phase o

D. Agboola

We present solutions of the Dirac equation with spin symmetry for vector and scalar modified Pöschl-Teller potential within framework of an approximation of the centrifugal term. The relativistic energy spectrum is obtained using the Nikiforov-Uvarov method and the two-component spinor wavefunctions are obtain are in terms of the Jacobi polynomials. It is fo

Ismail Zahed

Recent developments in holography have provided a new vista to the nucleon composition. A strongly coupled core nucleon tied with vector mesons emerge in line with the Cheshire cat principle. The cat is found to hide in the holographic direction. We discuss the one, two and many baryon problem in this context and point at the striking similarities between th