July 2008 arXiv papers — page 4

Shengli Zhang, Soung-Chang Liew

Physical-layer Network Coding (PNC) can significantly improve the throughput of wireless two way relay channel (TWRC) by allowing the two end nodes to transmit messages to the relay simultaneously. To achieve reliable communication, channel coding could be applied on top of PNC. This paper investigates link-by-link channel-coded PNC, in which a critical proc

Tôru Sakai, Masahiro Sato, Kouichi Okunishi, Yuichi Otsuka

We investigate quantum phase transitions of the S=1/2 three-leg antiferromagnetic spin tube with asymmetric inter-chain (rung) exchange interactions. On the basis of the electron tube system, we propose a useful effective theory to give the global phase diagram of the asymmetric spin tube. In addition, using other effective theories we raise the reliability

Max Nalsky

The article states that for every compact manifold M of dimension 4 or higher there is an area U in a set of smooth diffeomorphisms over M such that every map f from U has local maximal partially hyperbolic attractor and nonatomic ergodic invariant measure on it where one of Lyapunov exponents vanish. The result is first proved for skew products over horsesh

Dimitri Bourilkov

A review of the discovery potential of LHC for new phenomena beyond the Standard Model (BSM) other than Supersymmetry in the early phase of running is presented. Topics covered include searches for extra dimensions in different scenarios (ADD, Randall-Sundrum, black holes ...), resonance hunting in di-lepton, di-photon and di-jet final states, searches for c

Zhuang Liu, Joshua T. Robinson, Xiaoming Sun, Hongjie Dai

It is known that many potent, often aromatic drugs are water insoluble, which has hampered their use for disease treatment. In this work, we functionalized nano-graphene oxide (NGO), a novel graphitic material, with branched polyethylene glycol (PEG) to obtain a biocompatible NGO-PEG conjugate stable in various biological solutions, and used them for attachi

Delia Coculescu, Ashkan Nikeghbali

In this paper, we provide a solution to two problems which have been open in default time modeling in credit risk. We first show that if $τ$ is an arbitrary random (default) time such that its Azéma's supermartingale $Z_t^τ=¶(τ>t|\F_t)$ is continuous, then $τ$ avoids stopping times. We then disprove a conjecture about the equality between the hazard proc

M. Vesterinen, T. R. Wyatt

We present a novel method for studying the shape of the Z boson transverse momentum distribution, Q_T, at hadron colliders in ppbar/pp -> Z/gamma* -> l^+l^-. The Q_T is decomposed into two orthogonal components; one transverse and the other parallel to the di-lepton thrust axis. We show that the transverse component is almost insensitive to the momentum reso

Collin Bleak, Daniel Lanoue

We give a short argument showing that if $m, n \in {1, 2, ...} \cup ω$, then the groups mV and nV are not isomorphic. This answers a question of Brin.

Pierre Berger

We present a modern proof of some extensions of the celebrated Hirsch-Pugh-Shub theorem on persistence of normally hyperbolic compact laminations. Our extensions consist of allowing the dynamics to be an endomorphism, of considering the complex analytic case and of allowing the laminations to be non compact. To study the analytic case, we use the formalism o

K. V. Samokhin

We calculate the upper critical field, Hc2(T), due to the orbital pair breaking in disordered superconductors without inversion symmetry. Differences from the usual centrosymmetric case are highlighted. The linearized gap equations in magnetic field, with the singlet and triplet pairing channels mixed by impurity scattering, are solved exactly for a cubic cr

E. Steinbring, J. Melbourne, A. J. Metevier, D. C. Koo

We have employed laser guide star (LGS) adaptive optics (AO) on the Keck II telescope to obtain near-infrared (NIR) images in the Extended Groth Strip (EGS) deep galaxy survey field. This is a continuation of our Center for Adaptive Optics Treasury Survey (CATS) program of targeting 0.5<z<1 galaxies where existing images with the Hubble Space Telescope (HST)

S. B. Arnason, A. F. Hebard

We have used the two-step growth technique, quench condensing followed by an anneal, to grow ultra thin films of silver on glass substrates. As has been seen with semiconductor substrates this process produces a metastable homogeneous covering of silver. By measuring the in situ resistance of the film during growth we are able to see that the low temperature

Werner DePauli-Schimanovich

Zermelo&#39;s Axiom of Separation is: Exist x: Forall y: (y in x <==> y in a & E(y)) with definite(E) and parameter a. Thoralf Skolem suggested to characterize the terminus &#34;definite&#34; by &#34;the property E should be representable by a FOL formula&#34;. But that is trivial. &#34;definite&#34; must mean more. The author claims that &#34;definite&#34;

Filiberto Bilotti, Simone Tricarico, Lucio Vegni

In this paper, we present the design of cylindrical and spherical electromagnetic cloaks working at visible frequencies. The cloak design is based on the employment of layered structures consisting of alternating plasmonic and non-plasmonic materials and exhibiting the collective behavior of an effective epsilon-near-zero material at optical frequencies. The

N. Romero, S. Mchugh, M. P. Sarachik, S. A. Vitkalov

The non-linear zero-differential resistance state (ZDRS) that occurs for highly mobile two-dimensional electron systems in response to a dc bias in the presence of a strong magnetic field applied perpendicular to the electron plane is suppressed and disappears gradually as the magnetic field is tilted away from the perpendicular at fixed filling factor $ν$.

M. Klein, Y. Xiao, A. V. Gorshkov, M. Hohensee

We present a preliminary experimental study of the dependence on optical depth of slow and stored light pulses in Rb vapor. In particular, we characterize the efficiency of slow and stored light as a function of Rb density; pulse duration, delay and storage time; and control field intensity. Experimental results are in good qualitative agreement with theoret

Rainer J. Fries, Vincenzo Greco, Paul Sorensen

We review hadron formation from a deconfined quark gluon plasma (QGP) via coalescence or recombination of quarks and gluons. We discuss the abundant experimental evidence for coalescence from the Relativistic Heavy Ion Collider (RHIC) and compare the various coalescence models advocated in the literature. We comment on the underlying assumptions and remainin

Werner DePauli-Schimanovich

What is the slightest modification of ZF to add a complement-axiom? The answer in my Ph.D. thesis 1971 was ZF&#39;&#39;: Zermelo-Fraenkel with replacement for only well-founded domains and an omega-axiom. In 1974, Alonzo Church published a similar system, as did Urs Oswald in 1976. In his 1976 Ph.D. thesis, E. Mitchell also designed, a system very similar to

Graham D. Kribs, Adam Martin, Tuhin S. Roy

We demonstrate that the lightest chargino can be lighter than the lightest neutralino in supersymmetric models with Dirac gaugino masses as well as within a curious parameter region of the MSSM. Given also a light gravitino, such as from low scale supersymmetry breaking, this mass hierarchy leads to an unusual signal where every superpartner cascades down to

Marcello Cacciato, Frank C. van den Bosch, Surhud More, Ran Li

Galaxy clustering and galaxy-galaxy lensing probe the connection between galaxies and their dark matter haloes in complementary ways. On one hand, the halo occupation statistics inferred from the observed clustering properties of galaxies are degenerate with the adopted cosmology. Consequently, different cosmologies imply different mass-to-light ratios for d

Lara Nava, Giancarlo Ghirlanda, Gabriele Ghisellini, Claudio Firmani

The spectral-energy and (luminosity) correlations in long GRBs are being hotly debated to establish, first of all, their reality against possible selection effects. These are best studied in the observer planes, namely the peak energy E_peak_obs vs the fluence F or the peak flux P. In a recent paper we started to attack this problem considering all GRBs with

Gabriel Katz

Let G be a compact Lie group and A(G) its Burnside Ring. For a compact smooth n-dimensional G-manifold X equipped with a generic G-invariant vector field v, we prove an equivariant analog of the Morse formula Ind^G(v) = \sum_{k = 0}^{n} (-1)^k χ^G(\d_k^+X) which takes its values in A(G). Here Ind^G(v) denotes the equivariant index of the field v, {\d_k^+X\}

Hao Zhang, David J. Srolovitz, Jack F. Douglas*, James A. Warren

Polycrystalline materials can be viewed as composites of crystalline particles or grains separated from one another by thin amorphous grain boundary (GB) regions. While GB have been exhaustively investigated at low temperatures, where these regions resolve into complex ordered structures accessible to measurement, much less is known about them at higher temp

Masaki Asano, Takayuki Kubo, Shigeki Matsumoto, Masato Senami

It is demonstrated that the light Higgs boson scenario, which the lightest Higgs mass is less than the LEP bound, mh > 114.4 GeV, is consistent with the SUSY seesaw model. With the assumptions of the universal right-handed neutrino mass and the hierarchical mass spectrum of the ordinary neutrinos, the bounds for the right-handed neutrino mass is investigated

A. G. Winbow, L. V. Butov, A. C. Gossard

Photon storage with 250 ps rise time of the readout optical signal was implemented with indirect excitons in coupled quantum well nanostructures (CQW). The storage and release of photons was controlled by the gate voltage pulse. The transient processes in the CQW were studied by measuring the kinetics of the exciton emission spectra after application of the

M. Marta, A. Formicola, Gy. Gyurky, D. Bemmerer

The rate of the hydrogen-burning carbon-nitrogen-oxygen (CNO) cycle is controlled by the slowest process, 14N(p,gamma)15O, which proceeds by capture to the ground and several excited states in 15O. Previous extrapolations for the ground state contribution disagreed by a factor 2, corresponding to 15% uncertainty in the total astrophysical S-factor. At the La

Chunlei Liu

The CKM mechanism is well established as the dominant mechanism for $CP$ violation, which was first discovered in the neutral kaons in 1964 \cite{ref:cpkaon}. To search for new sources of CP violation, one can exploit a handful of systems in which the standard model makes a precise prediction of CP violation. In the $B^0_s\to J/ψϕ$ system, CP violation in th

Eyal Feigenbaum, Noam Kaminski, Meir Orenstein

When a negative slope of the dispersion curve is encountered, the propagating light may be either &#39;fast light&#39; or &#39;backward propagating&#39;. We show that causality considerations select only one of which for each scenario, and demonstrate that the same photonic (plasmonic) system can support both type of solutions depending on parameters.

T. Herpay, S. Razzaque, A. Patkos, P. Meszaros

We discuss the relevance of the curvature radiation of pions in strongly magnetized pulsars or magnetars, and their implications for the production of TeV energy neutrinos detectable by cubic kilometer scale detectors, as well as high energy photons.

T. Gorin, C. Pineda, H. Kohler, T. H. Seligman

Random matrix theory is used to represent generic loss of coherence of a fixed central system coupled to a quantum-chaotic environment, represented by a random matrix ensemble, via random interactions. We study the average density matrix arising from the ensemble induced, in contrast to previous studies where the average values of purity, concurrence, and en

Holger M. Kienle, Hausi A. Müller

In this paper we argue that policies are an increasing concern for organizations that are operating a web site. Examples of policies that are relevant in the domain of the web address issues such as privacy of personal data, accessibility for the disabled, user conduct, e-commerce, and intellectual property. Web site policies--and the overarching concept of

R. I. Eglitis, David Vanderbilt

We present the results of calculations of surface relaxations, energetics, and bonding properties for CaTiO3 (001) and (011) surfaces using a hybrid B3PW description of exchange and correlation. We consider both CaO and TiO2 terminations of the non-polar (001) surface, and Ca, TiO and O terminations of the polar (011) surface. On the (001) surfaces, we find

Ari M. Turner, Eugene Demler

Condensates of atoms with spins can have vortices of several types; these are related to the symmetry group of the atoms&#39; ground state. We discuss how, when a condensate is placed in a small magnetic field that breaks the spin symmetry, these vortices may form bound states. Using symmetry classification of vortex-charge and rough estimates for vortex int

Steffen Dereich, Peter Morters

We define a dynamic model of random networks, where new vertices are connected to old ones with a probability proportional to a sublinear function of their degree. We first give a strong limit law for the empirical degree distribution, and then have a closer look at the temporal evolution of the degrees of individual vertices, which we describe in terms of l

Matthew L. Wallace, Yves Gingras, Russell Duhon

We use a technique recently developed by Blondel et al. (2008) in order to detect scientific specialties from author cocitation networks. This algorithm has distinct advantages over most of the previous methods used to obtain cocitation &#34;clusters&#34;, since it avoids the use of similarity measures, relies entirely on the topology of the weighted network

M. B. Plenio, S. F. Huelga

Transport phenomena are fundamental in Physics. They allow for information and energy to be exchanged between individual constituents of communication systems, networks or even biological entities. Environmental noise will generally hinder the efficiency of the transport process. However, and contrary to intuition, there are situations in classical systems w

Nikolay Gromov, Victor Mikhaylov

The folded spinning string in AdS3 gives us an important insight into AdS/CFT duality. Recently its one-loop energy was analyzed in the context of AdS4/CFT3 by McLoughlin and Roiban arXiv:0807.3965, by Alday, Arutyunov and Bykov arXiv:0807.4400 and by Krishnan arXiv:0807.4561. They computed the spectrum of the fluctuations around the classical solution. In t

S. Tommasin, L. Spinoglio, K. Hainline, M. A. Malkan

The Spitzer high resolution spectra of 72 Seyfert galaxies from the 12$μ$m Galaxy Sample are presented and discussed. The presence of starburst components in these galaxies can be quantified by powerful mid-IR diagnostics tools (i.e. 11.25$μ$m PAH feature equivalent width and the H$_2$ emission line intensity), as well as the AGN dominance can be measured by

Leopoldo A. Pando Zayas, Daniel J. Phalen, Cesar A. Terrero-Escalante

We emphasize that non-conformal theories provide a natural playground for the ideas of the Maldacena conjecture, opening the possibility of exploring properties that could potentially be in the same universality class as QCD. In particular, we discuss in detail how light-like Wilson loops, an important ingredient in the prescription for scattering amplitudes

Andrei Kustarev

This paper deals with the question of J.Morava on existence of canonical complex cobordism class of singular submanifold. We present several solutions of this question for $X_r(ξ)$ -- the set of points where $\dimξ-r+1$ generic sections of a complex vector bundle $ξ$ are linearly dependent. The corresponding complex cobordism classes $Q_r(ξ)$ and $P_r(ξ)$ te

P. Chung, P. Danielewicz

A model-independent, three-dimensional source function for pion pairs has been extracted from Pb+Pb collisions at $\sqrt s_{NN}=17.3$ AGeV. The extracted sourc e exhibits long-range non-Gaussian tails in the directions of the pion-pair net transverse-momentum and of the beam. Comparison with the Therminator model allow s for an extraction of the pion source

Eugene B. Kolomeisky, Joseph P. Straley

Casimir forces are a manifestation of the change in the zero-point energy of the vacuum caused by the insertion of boundaries. We show how the Casimir force can be efficiently computed by consideration of the vacuum fluctuations that are suppressed by the boundaries, and rederive the scalar Casimir effects for a series of the Dirichlet geometries. For the pl

Peter Schupp, Jiangyang You

Noncommutative gauge theories defined via Seiberg-Witten map have desirable properties that theories defined directly in terms of noncommutative fields lack, covariance and unrestricted choice of gauge group and charge being among them, but nonperturbative results in the deformation parameter θare hard to obtain. In this article we use a θ-exact approach to

A. Garbarz, G. Giribet, F. D. Mazzitelli

In a recent work, it has been pointed out that certain observables of the massless scalar field theory in a static spherically symmetric background exhibit a universal behavior at large distances. More precisely, it was shown that, unlike what happens in the case the coupling to the curvature ξis generic, for the special cases ξ=0 and ξ= 1/6 the large distan

M. Alaei, S. Akbar Jafari, H. Akbarzadeh

Using first principle electronic structure calculations we investigated the role of substitutional doping of B,N,P,Al and vacancies (${\cal V}$) in diamond (X$_α$C$_{1-α}$). In the heavy doping regime, at about $\sim 1-6%$ doping an impurity band appears in the mid gap. Increasing further the concentration of the impurity substitution fills in the gap of the

Zhiyi Chi

Multiple hypothesis testing often involves composite nulls, i.e., nulls that are associated with two or more distributions. In many cases, it is reasonable to assume that there is a prior distribution on the distributions despite it is unknown. When the number of distributions under true nulls is finite, we show that under the above assumption, the false dis

S. A. Jafari

Hubbard model is an important model in theory of strongly correlated electron systems. In this contribution we introduce this model along with numerically exact method of diagonalization of the model.

Kathrin Bringmann, Jeremy Lovejoy, Robert Osburn

We study two types of crank moments and two types of rank moments for overpartitions. We show that the crank moments and their derivatives, along with certain linear combinations of the rank moments and their derivatives, can be written in terms of quasimodular forms. We then use this fact to prove exact relations involving the moments as well as congruence

Martin Bojowald

Different aspects of relativity, mainly in a canonical formulation, relevant for the question &#34;Is spacetime nothing more than a mathematical space (which describes the evolution in time of the ordinary three-dimensional world) or is it a mathematical model of a real four-dimensional world with time entirely given as the fourth dimension?&#34; are present

Mohsen Hafez, S. A. Jafari, M. R. Abolhassani

Taking the site-diagonal terms of the one-dimensional ionic Hubbard model (IHM) as $H_0$, we employ Continuous Unitary Transformations (CUT) to obtain a &#34;classical&#34; effective Hamiltonian in which hopping term has been integrated out. For this Hamiltonian spin gap and charge gap are calculated at half-filling and subject to periodic boundary condition

Jun Zhao, Q. Huang, Clarina de la Cruz, J. W. Lynn

We use powder neutron diffraction to study the spin and lattice structures of polycrystalline samples of nonsuperconducting PrFeAsO and superconducting PrFeAsO0.85F0.15 and PrFeAsO0.85. We find that PrFeAsO exhibits an abrupt structural phase transitions at 153 K, followed by static long range antiferromagnetic order at 127 K. Both the structural distortion

Jean-Paul Zahn

To first approximation, a binary system conserves its angular momentum while it evolves to its state of minimum kinetic energy: circular orbit, all spins aligned, and components rotating in synchronism with the orbital motion. The pace at which this final state is achieved depends on the physical processes that are responsible for the dissipation of the tida

Tatsuya Fujii

Recently we have developed a theory of Keldysh formalism for mesoscopic systems. The resulting nonequilibrium Kubo formula for differential conductance makes it possible to propose the new formula of shot noise $S_h$, and thus to study shot noise in correlated systems at any temperature and any bias voltage. Employing this new approach, we analyze shot noise

Omar Valsson, Chi-Shung Tang, Vidar Gudmundsson

We investigate phase coherent electronic transport in an open quantum system, which consists of quantum dots side-coupled to a nanowire. It is demonstrated that coherent switching can be characterized by adjusting the electronic energy. A comparative analysis of quantum coherence effects in side-coupled quantum-dot systems is presented. Our results demonstra

Jianhua Z. Huang, Haipeng Shen, Andreas Buja

Two existing approaches to functional principal components analysis (FPCA) are due to Rice and Silverman (1991) and Silverman (1996), both based on maximizing variance but introducing penalization in different ways. In this article we propose an alternative approach to FPCA using penalized rank one approximation to the data matrix. Our contributions are four

Zoltan Spiro, Istvan A. Kovacs, Peter Csermely

Recently, a number of drug-therapy, disease, drug, and drug-target networks have been introduced. Here we suggest novel methods for network-based prediction of novel drug targets and for improvement of drug efficiency by analysing the effects of drugs on the robustness of cellular networks.

Jean-Michel Loubes, Carenne Ludeña

We tackle the problem of building adaptive estimation procedures for ill-posed inverse problems. For general regularization methods depending on tuning parameters, we construct a penalized method that selects the optimal smoothing sequence without prior knowledge of the regularity of the function to be estimated. We provide for such estimators oracle inequal

Seth D. Tribble, Art B. Owen

In Markov chain Monte Carlo (MCMC) sampling considerable thought goes into constructing random transitions. But those transitions are almost always driven by a simulated IID sequence. Recently it has been shown that replacing an IID sequence by a weakly completely uniformly distributed (WCUD) sequence leads to consistent estimation in finite state spaces. Un

V. I. Zagrebaev

The so called &#34;barrier distribution&#34; derived from quasi-elastic backscattering of heavy ions gives us, in fact, an information about the &#34;reaction threshold distribution&#34;. For light nuclear systems these distributions are quite close, but for heavy ones (when interaction of nuclei becomes more and more complicated and the potential barrier ca

Alberto Rodriguez, Louella J. Vasquez, Rudolf A. Roemer

We study various box-size scaling techniques to obtain the multifractal properties, in terms of the singularity spectrum f(alpha), of the critical eigenstates at the metal-insulator transition within the 3-D Anderson model of localisation. The typical and ensemble averaged scaling laws of the generalised inverse participation ratios are considered. In pursui

Chen Ben-David, Amir Leshem

The increased sensitivity of future radio telescopes will result in requirements for higher dynamic range within the image as well as better resolution and immunity to interference. In this paper we propose a new matrix formulation of the imaging equation in the cases of non co-planar arrays and polarimetric measurements. Then we improve our parametric imagi

S. Bickman, P. Hamilton, Y. Jiang, D. DeMille

We are pursuing an experiment to measure the electric dipole moment of the electron using the molecule PbO. This measurement requires the ability to prepare quantum states with orientation of the molecular axis and, simultaneously, alignment of the electron spin perpendicular to this axis. It also requires efficient detection of the evolution of the spin ali

Matthew Middleton, Chris Done, Martin Ward, Marek Gierlinski

The X-ray quasi-periodic oscillation (QPO) seen in RE J1034+396 is so far unique amongst AGN. Here we look at the another unique feature of RE J1034+396, namely its huge soft X-ray excess, to see if this is related in any way to the detection of the QPO. We show that all potential models considered for the soft energy excess can fit the 0.3-10 keV X-ray spec

P. S. Eldridge, W. J. H Leyland, J. D. Mar, P. G. Lagoudakis

To an electron moving in free space an electric field appears as a magnetic field which interacts with and can reorient the electron spin. In semiconductor quantum wells this spin-orbit interaction seems to offer the possibility of gate-voltage control in spintronic devices but, as the electrons are subject to both ion-core and macroscopic structural potenti

Philipp Eigmüller, Jochen Eislöffel

The Tautenburg Exoplanet Search Telescope (TEST) is a robotic telescope system. The telescope uses a folded Schmidt Camera with a 300mm main mirror. The focal length is 940mm and it gives a 2.2 square degree field of view. Dome, mount, and CCD cameras are controlled by a software bundle made by Software Bisque. The automation of the telescope includes select

Line Hjortshoj Pedersen, Niels Martin Moller, Klaus Molmer

When applied to different input states, an imperfect quantum operation yields output states with varying fidelities, defined as the absolute square of their overlap with the desired states. We present an expression for the distribution of fidelities for a class of operations applied to a general qubit state, and we present general expressions for the varianc

Wolfgang Ebeling

A boundary singularity is a singularity of a function on a manifold with boundary. The simple and unimodal boundary singularities were classified by V. I. Arnold and V. I. Matov. The McKay correspondence can be generalized to the simple boundary singularities. We consider the monodromy of the simple, parabolic, and exceptional unimodal boundary singularities

I. S. Nurgaliev

The cosmological models in the frame of the Newtonian and general relativistic treatments are considered. The centrifugal forces acting between particles rotating randomly around each other are shown to be able to reverse gravitational collapse.

Werner DePauli-Schimanovich

In this article the author claims that there is a paradigm shift from ZFC to NFUM and further to NACT - due to philosophical reasons, not mathematical ones. The goal is to construct systems where every &#34;Not-Properclass&#34; is a set! With help of Non-Monotonic Logic, the consistent systems NACT-MoonW, NACT*W, and NACT-SunW are producing &#34;largest poss

Ahmet Dernek, Nese Dernek, Osman Yurekli

In the present paper the authors show that iterations of the Hankel transform with $\mathscr{K}_ν$-transform is a constant multiple of the Widder transform. Using these iteration identities, several Parseval-Goldstein type theorems for these transforms are given. By making use of these results a number of new Goldstein type exchange identities are obtained f

Sander Zwegers

In this Ph.D. thesis, written under the direction of D.B. Zagier and R.W. Bruggeman, we study the mock theta functions, that were introduced by Ramanujan. We show how they can be interpreted in the theory of (real-analytic) modular forms. In Chapter 1 we give results for Lerch sums (also called Appell functions, or generalized Lambert series). In Chapter 2 w

Shi-Hua Ouyang, J. Q. You, Franco Nori

We study the cooling of a mechanical resonator (MR) that is capacitively coupled to a double quantum dot (DQD). The MR is cooled by the dynamical backaction induced by the capacitive coupling between the DQD and the MR. The DQD is excited by a microwave field and afterwards a tunneling event results in the decay of the excited state of the DQD. An important

J. M. Aldaz

We explore the concentration properties of the ratio between the geometric mean and the arithmetic mean, showing that for certain sequences of weights one does obtain concentration, around a value that depends on the sequence.

Victor Maltcev

In this note we prove that, for a finite semigroup $S$, the dual Cayley automaton semigroup $\mathbf{C^{\ast}}(S)$ is finite if and only if $S$ is $\mathcal{H}$-trivial and has no non-trivial right zero subsemigroups.

R. Alonso, S. Aigrain, F. Pont, T. Mazeh

With more than 80 transits observed in the CoRoT light curve with a cadence of 32 s, CoRoT-Exo-2b provides an excellent case to search for the secondary eclipse of the planet, with an expected signal of less than 10^-4 in relative flux. The activity of the star causes a modulation on the flux that makes the detection of this signal challenging. We describe t

S. Somorendro Singh, D. S. Gosain, Yogesh kumar, Agam K. Jha

The free energy of a Quark-Gluon Plasma fireball in the hadronic medium is calculated in the Ramanathan et al. statistical model including the effect of curvature. The result with this curvature is found to produce significant improvement from earlier results in all the parameters we calculated. The surface tension with this curvature effect is found to be $

Uma Divakaran, Amit Dutta

We study the breakdown of a random fiber bundle model (RFBM) with $n$-discontinuities in the threshold distribution using the global load sharing scheme. In other words, $n+1$ different classes of fibers identified on the basis of their threshold strengths are mixed such that the strengths of the fibers in the $i-th$ class are uniformly distributed between t

Andreas Blicher, Katarzyna Wodzinska, Matthias Fidorra, Mathias Winterhalter

We investigate the permeability of lipid membranes for fluorescence dyes and ions. We find that permeability reaches a maximum close to the chain melting transition of the membranes. Close to transitions, fluctuations in area and compressibility are high, leading to an increased likelihood of spontaneous lipid pore formation. Fluorescence Correlation Spectro

F. Arqueros, F. Blanco, D. Garcia-Pinto, M. Ortiz

Detection of the air-fluorescence radiation induced by the charged particles of extensive air showers is a well-established technique for the study of ultra-high energy cosmic rays. Fluorescence telescopes provide a nearly calorimetric measure of the primary energy. Presently the main source of systematic uncertainties comes from our limited accuracy in the

N. Linder, G. Rauw, F. Martins, H. Sana

We present here the analysis of an extensive set of high resolution optical spectra of Plaskett&#39;s star (HD 47129). We use a disentangling method to separate the individual spectra of each star. We derive a new orbital solution and discuss the spectral classification of both components. A Doppler tomography technique applied to the emission lines H alpha

Jean-Marc Couveignes, Emmanuel Hallouin

To every covering of curves, we associate several varieties having the same field of moduli and same fields of definition. We deduce examples of curves having Q (the field of rationals) as field of moduli, that admit models over any completion of Q but no model over Q.

S. Scopetta, A. Courtoy, F. Fratini, V. Vento

A formalism to evaluate the Sivers function, developed for calculations in constituent quark models, is applied to the Isgur-Karl model. A non-vanishing Sivers asymmetry, with opposite signs for the u and d flavor, is found; the Burkardt sum rule is fulfilled up to 2 %. Nuclear effects in the extraction of neutron single spin asymmetries in semi-inclusive de

David W. Hogg

Data points are placed in bins when a histogram is created, but there is always a decision to be made about the number or width of the bins. This decision is often made arbitrarily or subjectively, but it need not be. A jackknife or leave-one-out cross-validation likelihood is defined and employed as a scalar objective function for optimization of the locati

Man-Hong Yung

The success of adiabatic quantum computation (AQC) depends crucially on the ability to maintain the quantum computer in the ground state of the evolution Hamiltonian. The computation process has to be sufficiently slow as restricted by the minimal energy gap. However, at finite temperatures, it might need to be fast enough to avoid thermal excitations. The q

S. S. Kannan, S. K. Pattanayak

In this paper, for any simple, simply connected algebraic group $G$ of type $B_n,C_n$ or $D_n$ and for any maximal parabolic subgroup $P$ of $G$, we describe all minimal dimensional Schubert varieties in $G/P$ admitting semistable points for the action of a maximal torus $T$ with respect to an ample line bundle on $G/P$. In this paper, we also describe, for

Carlos Currás-Bosch

Any singular level of a completely integrable system (c.i.s.) with non-degenerate singularities has a singular affine structure. We shall show how to construct a simple c.i.s. around the level, having the above affine structure. The cotangent budle of the desingularised level is used to perform the construction, and the c.i.s. obtained looks like the simples

M. Viallet, J. -M. Hameury

We discuss two mechanisms that could result in an enhancement of the mass transfer rate during outbursts of dwarf novae and soft X-ray transients: the hot outer disc rim itself could heat the L1 point and scattered radiation by optically thin outflowing matter could also heat L1 significantly. We determine quantitatively the increase of the mass transfer rat

Yu-Feng Zhou

The effects of flavor mixing in electroweak baryogenesis is investigated in a generalized semiclassical WKB approach. Through calculating the nonadiabatic corrections to the particle currents it is shown that extra CP violation sources arise from the off-diagonal part of the equation of motion of particles moving inside the bubble wall. The numerical importa

Maurice Duits, Arno B. J. Kuijlaars

The eigenvalue statistics of a pair $(M_1,M_2)$ of $n\times n$ Hermitian matrices taken random with respect to the measure $$\frac{1}{Z_n}\exp\big(-n\Tr (V(M_1)+W(M_2)-τM_1M_2)\big) {\rm d}M_1 {\rm d} M_2 $$ can be described in terms of two families of biorthogonal polynomials. In this paper we give a steepest descent analysis of a $4 \times 4$ matrix-valued

Gregor Diezemann, Andreas Janshoff

We consider reversible breaking of adhesion bonds or folding of proteins under the influence of a constant external force. We discuss the stochastic properties of the unbinding/rebinding events and analyze their mean number and their variance in the framework of simple two-state models. In the calculations, we exploit the analogy to single molecule fluoresce

Ammar Faouzi, Kamoun Kaouthar

We study non-trivial deformations of the natural action of the Lie superalgebra $mathcalK(1)$ of contact vector fields on the (1,1)-dimensional superspace $mathbbR^{1|1}$ of th espace of symbols. We calculate obstructions for integrability of infinitesimal multi-parameter deformation and determine the complete commutative algebra corresponding to the miniver

A. S. Rybalko, S. P. Rubets, E. Ya. Rudavskii, V. A. Tikhiy

The interaction between electromagnetic microwaves (40-200 GHz) and superfluid helium in a stationary electric field has been investigated experimentally. It is found that the narrow line of resonance absorption at the roton frequency is split in the electric field into two symmetric lines. The splitting magnitude increases almost linearly with the electric

F. Baroncini, A. Kievsky, E. Pace, G. Salme`

This contribution briefly illustrates preliminary calculations of the electromagnetic form factors of $^3$He and $^3$H, obtained within the Light-front Relativistic Hamiltonian Dynamics, adopting i) a Poincaré covariant current operator, without dynamical two-body currents, and ii) realistic nuclear bound states with $S$, $P$ and $D$ waves. The kinematical r

Raimundas Vidunas

A celebrated theorem of Klein implies that any hypergeometric differential equation with algebraic solutions is a pull-back of one of the few standard hypergeometric equations with algebraic solutions. The most interesting cases are hypergeometric equations with tetrahedral, octahedral or icosahedral monodromy groups. We give an algorithm for computing Klein

Paul Van Dooren, Kyle A. Gallivan, P. -A. Absil

We consider the problem of approximating a multiple-input multiple-output (MIMO) $p\times m$ rational transfer function $H(s)$ of high degree by another $p\times m$ rational transfer function $\hat H(s)$ of much smaller degree, so that the ${\cal H}_2$ norm of the approximation error is minimized. We characterize the stationary points of the ${\cal H}_2$ nor

S. Vaughan, P. Uttley

In recent years there have been many reported detections of highly redshifted or blueshifted narrow spectral lines (both emission or absorption) in the X-ray spectra of active galaxies, but these are all modest detections in terms of their statistical significance. The aim of this paper is to review the issue of the significance of these detections and, in p

G. Chiribella, G. M. D&#39;Ariano, D. M. Schlingemann

We analyze the convex structure of the set of positive operator valued measures (POVMs) representing quantum measurements on a given finite dimensional quantum system, with outcomes in a given locally compact Hausdorff space. The extreme points of the convex set are operator valued measures concentrated on a finite set of k \le d^2 points of the outcome spac

Nicolás Botbol, Alicia Dickenstein, Marc Dohm

In this paper we show that a surface in P^3 parametrized over a 2-dimensional toric variety T can be represented by a matrix of linear syzygies if the base points are finite in number and form locally a complete intersection. This constitutes a direct generalization of the corresponding result over P^2 established in [BJ03] and [BC05]. Exploiting the sparse

Matthew B. Day

We define a family of groups that include the mapping class group of a genus g surface with one boundary component and the integral symplectic group Sp(2g,Z). We then prove that these groups are finitely generated. These groups, which we call mapping class groups over graphs, are indexed over labeled simplicial graphs with 2g vertices. The mapping class grou

Matthew B. Day

We generalize the peak-reduction algorithm (Whitehead&#39;s theorem) for free groups to a theorem about a general right-angled Artin group A_Gamma. As an application, we find a finite presentation for the automorphism group Aut A_Gamma that generalizes McCool&#39;s presentation for the automorphism group of a finite rank free group. We also give consider a s