July 2009 arXiv papers — page 7

Shai Haim, Toby Walsh

We present two different methods for estimating the cost of solving SAT problems. The methods focus on the online behaviour of the backtracking solver, as well as the structure of the problem. Modern SAT solvers present several challenges to estimate search cost including coping with nonchronological backtracking, learning and restarts. Our first method adap

Shai Haim, Toby Walsh

Restart strategies are an important factor in the performance of conflict-driven Davis Putnam style SAT solvers. Selecting a good restart strategy for a problem instance can enhance the performance of a solver. Inspired by recent success applying machine learning techniques to predict the runtime of SAT solvers, we present a method which uses machine learnin

D. Kurt Gaskill, Glenn G. Jernigan, Paul M. Campbell, Joseph L. Tedesco

An in vacuo thermal desorption process has been accomplished to form epitaxial graphene (EG) on 4H- and 6H-SiC substrates using a commercial chemical vapor deposition reactor. Correlation of growth conditions and the morphology and electrical properties of EG are described. Raman spectra of EG on Si-face samples were dominated by monolayer thickness. This ap

Joseph L. Tedesco, Brenda L. VanMil, Rachael L. Myers-Ward, James C. Culbertson

Graphene was epitaxially grown on both the C- and Si-faces of 4H- and 6H-SiC(0001) under an argon atmosphere and under high vacuum conditions. Following growth, samples were imaged with Nomarski interference contrast and atomic force microscopies and it was found that growth under argon led to improved morphologies on the C-face films but the Si-face films w

Brenda L. VanMil, Rachael L. Myers-Ward, Joseph L. Tedesco, Charles R. Eddy,

Graphene layers were created on both C and Si faces of semi-insulating, on-axis, 4H- and 6H-SiC substrates. The process was performed under high vacuum (<10-4 mbar) in a commercial chemical vapor deposition SiC reactor. A method for H2 etching the on-axis sub-strates was developed to produce surface steps with heights of 0.5 nm on the Si-face and 1.0 to 1.5

Joseph L. Tedesco, Brenda L. VanMil, Rachael L. Myers-Ward, Joseph M. McCrate

Epitaxial graphene films were grown in vacuo by silicon sublimation from the (0001) and (000-1) faces of 4H- and 6H-SiC. Hall effect mobilities and sheet carrier densities of the films were measured at 300 K and 77 K and the data depended on the growth face. About 40% of the samples exhibited holes as the dominant carrier, independent of face. Generally, mob

David K. Sing, J. -M. Desert, A. Lecavelier des Etangs, G. E. Ballester

We present Hubble Space Telescope near-infrared transit photometry of the nearby hot-Jupiter HD189733b. The observations were taken with the NICMOS instrument during five transits, with three transits executed with a narrowband filter at 1.87 microns and two performed with a narrowband filter at 1.66 microns. Our observing strategy using narrowband filters i

D. G. Cerdeno, Y. Mambrini, A. Romagnoni

We study the phenomenology of generic supergravity models in which gravity mediation naturally competes with gauge mediation as the origin of supergravity-breaking. This class of hybrid models has been recently motivated in string inspired constructions and differs from usual gauge mediated supersymmetry breaking models in having messenger masses of order of

Luis J. Alias, G. Pacelli Bessa, J. Fabio Montenegro

We give sharp sectional curvature estimates for complete immersed cylindrically bounded $m$-submanifolds $ϕ:M\to N\times\mathbb{R}^{\ell}$, $n+\ell\leq 2m-1$ provided that either $ϕ$ is proper with the second fundamental form with certain controlled growth or $M$ has scalar curvature with strong quadratic decay. This latter gives a non-trivial extension of t

D. Dalmazi, E. L. Mendonca

There are three self-dual models of massive particles of helicity +2 (or -2) in $D=2+1$. Each model is of first, second, and third-order in derivatives. Here we derive a new self-dual model of fourth-order, $\cL {SD}^{(4)}$, which follows from the third-order model (linearized topologically massive gravity) via Noether embedment of the linearized Weyl symmet

P. Kazakopoulos, P. Mertikopoulos, A. L. Moustakas, G. Caire

Using a large deviations approach we calculate the probability distribution of the mutual information of MIMO channels in the limit of large antenna numbers. In contrast to previous methods that only focused at the distribution close to its mean (thus obtaining an asymptotically Gaussian distribution), we calculate the full distribution, including its tails

A. M. Glenn

We present Hanbury-Brown Twiss measurements from the PHENIX experiment at RHIC for final results for charged kaon pairs from sqrt{s_{NN}} = 200 GeV Au+Au collisions and preliminary results for charged pion pairs from sqrt{s} = 200 GeV p+p collisions. We find that for kaon pairs from Au+Au, each traditional 3D Gaussian radius shows approximately the same line

Vida Milani, Seyed M. H. Mansourbeigi, Farzaneh Falahati

The paper is constructed in two parts.In the first part we introduce the concept of the algebra of Q-meromorphic functions on the quantum plane.The A (q)-algebra of Q-analytic functions considered in[6]is seen as a proper subalgebra. In the second part we find a formula for the curvature tensor on this algebra. It is seen that when the quantization parameter

Brian Humensky

The study of supernova remnants and pulsar wind nebulae was one of the Key Science Projects for the first two years of VERITAS observations. VERITAS is an array of four imaging Cherenkov telescopes located at the Whipple Observatory in southern Arizona. Supernova remnants are widely considered to be the strongest candidate for the source of cosmic rays below

Brian Humensky

The study of shell-type supernova remnants is a key science focus for the VERITAS TeV telescope array. Supernova remnants (SNRs) are widely considered to be the strongest candidate for the source of cosmic rays below the knee around 10^15 eV. This presentation will highlight new VERITAS results including new measurements of the spectra of Cas A and IC 443 an

Hurlee Gonchigdanzan

In this paper we investigate how much Hamiltonian cycles weigh in K_4 and K_5 compare to the total weight of the graph and establish precise estimates.

Denes Molnar, Pasi Huovinen

In an earlier work (arXiv:0808.0953) we established that causal Israel-Stewart viscous hydrodynamics is only accurate in RHIC applications at very low shear viscosities 4 pi eta_s / s < ~ 1.5-2. We show here that the region of applicability is significantly reduced if bulk viscosity plays a role in the dynamics.

Amanda de Lima, Daniel Smania

We show that for a large class of piecewise expanding maps T, the bounded p-variation observables u_0 that admits an infinite sequence of bounded p-variation observables u_i satisfying u_i(x)= u_{i+1}(Tx) -u_{i+1}(x) are constant. The method of the proof consists in to find a suitable Hilbert basis for L^2(hm), where hm is the unique absolutely continuous in

Jaqueline Morgan, Vitor Cardoso, Alex S. Miranda, C. Molina

The AdS/CFT duality has established a mapping between quantities in the bulk AdS black-hole physics and observables in a boundary finite-temperature field theory. Such a relationship appears to be valid for an arbitrary number of spacetime dimensions, extrapolating the original formulations of Maldacena&#39;s correspondence. In the same sense properties like

M. Veneziani, P. A. R. Ade, J. J. Bock, A. Boscaleri

The physical properties of galactic cirrus emission are not well characterized. BOOMERanG is a balloon-borne experiment designed to study the cosmic microwave background at high angular resolution in the millimeter range. The BOOMERanG 245 and 345GHz channels are sensitive to interstellar signals, in a spectral range intermediate between FIR and microwave fr

V. Cardoso, L. Gualtieri

Dynamical Chern-Simons (DCS) modified gravity is an attractive, yet relatively unexplored, candidate to an alternative theory of gravity. The DCS correction couples a dynamical scalar field to the gravitational field. In this framework, we analyze the perturbation formalism and stability properties of spherically symmetric black holes. Assuming that no backg

V. N. Biktashev, D. Barkley, I. V. Biktasheva

Spiral waves in active media react to small perturbations as particle-like objects. Here we apply the asymptotic theory to the interaction of spiral waves with a localized inhomogeneity, which leads to a novel prediction: drift of the spiral rotation centre along circular orbits around the inhomogeneity. The stationary orbits have alternating stability and f

Dimitrios Giannios, Dmitri A. Uzdensky, Mitchell C. Begelman

The jet of the radio galaxy M87 is misaligned, resulting in a Doppler factor delta~1 for emission of plasma moving parallel to the jet. This makes the observed fast TeV flares on timescales of t_v~5R_g/c harder to understand as emission from the jet. In previous work, we have proposed a jets-in-a-jet model for the ultra-fast TeV flares with t_v<<R_g/c seen i

Roberta Arnaldi

Charmonia suppression is one of the main signatures for the formation of a deconfined medium. However, also nuclear effects, not related to the production of a hot medium, can affect the J/psi yield. The determination, from the study of p-A collisions, of the J/psi behaviour in nuclear matter is, therefore, extremely important to correctly quantify the amoun

J. K. Lawrence, A. C. Cadavid

We study the space-time distributions of intensity fluctuations in 2 - 3 hour sequences of multi-spectral, high-resolution, high-cadence broad-band filtergram images (BFI) made by the SOT-FG system aboard the Hinode spacecraft. In the frequency range 5.5 < f < 8.0 mHz both G-band and Ca II H-line oscillations are suppressed in the presence of magnetic fields

Nicola Galante

Radio galaxies are the only non-blazar extragalactic objects detected in the VHE (E >100 GeV) band. These objects enable the investigation of the main substructures of the AGN, in particular the core, the jet and its interaction with the intergalactic environment. Clusters of galaxies, instead, have not been detected by gamma-ray observatories. These objects

Eric Brown, Nicole A. Forman, Carlos S. Orellana, Hanjun Zhang

Suspensions are of wide interest and form the basis for many smart fluids. For most suspensions, the viscosity decreases with increasing shear rate, i.e. they shear thin. Few are reported to do the opposite, i.e. shear thicken, despite the longstanding expectation that shear thickening is a generic type of suspension behavior. Here we resolve this apparent c

Nicola Galante

During its first cycle of observations, VERITAS observed several GRBs in response to broadcast alerts from the Gamma-ray bursts Coordinates Network (GCN). The GRBs were followed up and observed thereafter with typical delays of 2 to 4 minutes from the beginning of the burst and of 92 s in the best case, searching for a very high energy (VHE) component above

Josiah Schwab, Adam S. Bolton, Saul A. Rappaport

Galaxy-scale strong gravitational lenses with measured stellar velocity dispersions allow a test of the weak-field metric on kiloparsec scales and a geometric measurement of the cosmological distance-redshift relation, provided that the mass-dynamical structure of the lensing galaxies can be independently constrained to a sufficient degree. We combine data o

Krzysztof Belczynski, Janusz Ziolkowski

In the Galaxy there are 64 Be X-ray binaries known to-date. Out of those, 42 host a neutron star, and for the reminder the nature of a companion is not known. None, so far, is known to host a black hole. There seems to be no apparent mechanism that would prevent formation or detection of Be stars with black holes. This disparity is referred to as a missing B

Hassan Firouzjahi, Johanna Karouby, Shahram Khosravi, Robert Brandenberger

In this paper the collision of two cosmic string loops is studied. After collision junctions are formed and the loops are entangled. We show that after their formation the junctions start to unzip and the loops disentangle. This analysis provides a theoretical understanding of the unzipping effect observed in numerical simulations of a network of cosmic stri

Remigiusz Augusiak, Janusz Grabowski, Marek Kuś, Maciej Lewenstein

We study extremality in various sets of states that have positive partial transposes. One of the tools we use for this purpose is the recently formulated criterion allowing to judge if a given state is extremal in the set of PPT states. First we investigate qubit--ququart states and show that the only candidates for extremal PPT entangled states (PPTES) have

Gábor I. Veres

The capabilities of the CMS detector at the LHC will be described for measuring high-pT hadrons, photons and jets in heavy ion collisions. Detailed simulations of various studies planned with the CMS apparatus, including charged particle tracking, jet reconstruction using calorimetry, dimuon and isolated photon detection and the measurement of in-medium frag

J. S. Perkins

Blazars are among the most energetic and violent objects in the universe. By observing blazars at very high energies (VHE, E > 100 GeV) we can better understand blazar emission mechanisms, jet structure, black hole accretion and the extragalactic background light (EBL). VERITAS, an array of four 12-meter diameter imaging atmospheric-Cherenkov telescopes, per

Tristan L. Smith

Modifications to GR generically predict time and scale-dependent effects which may be probed by observations of strong lensing by galaxies. Measurements of the stellar velocity dispersion determine the dynamical mass whereas measurements of the Einstein radius determine the lensing mass. In GR these two masses are equal; in alternative gravity theories they

W. A. Horowitz

We first note the failures of traditional pQCD techniques as applied to high-pT heavy ion physics and the suggestion of examining the double ratio of charm to bottom nuclear modification factors to generically distinguish between these weak coupling ideas and the strong coupling ideas of AdS/CFT. In order to gain confidence in the use of AdS/CFT (and to incr

J. Noronha-Hostler, J. Noronha, H. Ahmad, I. Shovkovy

We discuss how the inclusion of Hagedorn states near $T_c$ leads to short chemical equilibration times of proton anti-proton pairs, $K\bar{K}$ pairs, and $Λ\barΛ$ pairs, which indicates that hadrons do not need to be &#34;born&#34; into chemical equilibrium in ultrarelativistic heavy ion collisions. We show that the hadron ratios computed within our model ma

Steven S. Gubser

I outline some of the progress over the past few years in applying ideas from string theory to study the quark-gluon plasma, including the computation of the drag force on heavy quarks and estimates of total multiplicity from black hole formation. I also indicate some of the main perils of the string theory approach.

Michael McCutcheon

It has been postulated that globular clusters could be sources of Very-High Energy (VHE) gamma rays, powered by milli-second pulsars. This could be due to cumulative direct emission or to plerion-type emission driven by colliding winds. In particular the southern hemisphere globular cluster 47 Tuc has been singled out as a potential source in both models. In

F. R. Klinkhamer, G. E. Volovik

The standard model of elementary particle physics and the theory of general relativity can be extended by the introduction of a vacuum variable which is responsible for the near vanishing of the present cosmological constant (vacuum energy density). The explicit realization of this vacuum variable can be via a three-form gauge field, an aether-type velocity

Xavier Tolsa

In this paper we prove that if f is a planar K-quasiconformal map and 0<t<2, t&#39; = 2t/(2K-Kt+t), then f transforms sets of finite (t&#39;)-Hausdorff measure into sets of finite t-Hausdorff measure. We also prove the following more quantitative statement: If E is a planar set, then H^t(E) \leq C(K) H^{t&#39;}(f(E))^{t/(t&#39;K)}, where H^s stands for the s

Rajat Kumar Pradhan

A phenomenological approach using the states of spin-like observables is developed to understand the nature of consciousness and the totality of experience. The three states of consciousness are taken to form the triplet of eigenstates of a spin-one entity and are derived as the triplet resulting from the composition of two spins by treating the subject and

Ermias T. Atomssa

Three measurements that broaden the scope of the experimental investigation of quarkonia modifications in heavy ion collisions are presented. Although the current statistical precision on the first two measurements does not allow one to draw significant conclusions, J/$\psi$ elliptic flow and high pT suppression results are important proofs of principle meas

L. R. Arnaut

We derive the sampling probability density function (pdf) of an ideal localized random electromagnetic field, its amplitude and intensity in an electromagnetic environment that is quasi-statically time-varying statistically homogeneous or static statistically inhomogeneous. The results allow for the estimation of field statistics and confidence intervals whe

Feng Dai, Yuan Xu

A new modulus of smoothness based on the Euler angles is introduced on the unit sphere and is shown to satisfy all the usual characteristic properties of moduli of smoothness, including direct and inverse theorem for the best approximation by polynomials and its equivalence to a $K$-functional, defined via partial derivatives in Euler angles. The set of resu

Young-Heon Kim, Robert J. McCann, Micah Warren

Given a transportation cost $c: M \times\bar M \to\mathbf{R}$, optimal maps minimize the total cost of moving masses from $M$ to $\bar M$. We find a pseudo-metric and a calibration form on $M\times\bar M$ such that the graph of an optimal map is a calibrated maximal submanifold. We define the mass of space-like currents in spaces with indefinite metrics.

Roger Colbeck, Renato Renner

In [Physical Review Letters 101, 050403 (2008)], we showed that quantum theory cannot be explained by a hidden variable model with a non-trivial local part. The purpose of this comment is to clarify our notion of local part, which seems to have caused some confusion in the recent literature. This notion is based on Bell&#39;s and demands that local hidden va

Chin-Hao Chen

By tuning several experimental observables, such as momentum and reaction plane, the PHENIX experiment has performed a systematic study of high $p_T$ parton energy loss in hot nuclear matter, as well as jet induced medium modifications, such as the ridge and shoulder. Baseline d+Au measurements are also studied to provide the comparison as control of cold nu

Vladimir Dotsenko

We show how to use Groebner bases for operads to prove various freeness theorems: freeness of certain operads as nonsymmetric operads, freeness of an operad Q as a P-module for an inclusion P into Q, freeness of a suboperad. This gives new proofs of many known results of this type and helps to prove some new results.

The D0 Collaboration, V. Abazov

We present measurements of the anomalous WWgamma and WWZ trilinear gauge couplings from a combination of four diboson production and decay channels using data collected by the D0 detector at the Fermilab Tevatron Collider. These results represent the first high statistics combination of limits across different diboson production processes at the Tevatron and

Clément de Seguins Pazzis

In a recent article, we gave a full characterization of matrices that can be decomposed as a linear combination of two idempotents with prescribed coefficients. In this one, we use those results to improve on a recent theorem of V. Rabanovich: we establish that every square matrix is a linear combination of three idempotents (for an arbitrary coefficient fie

Jan E. Grabowski

We give several explicit examples of quantum cluster algebra structures, as introduced by Berenstein and Zelevinsky, on quantized coordinate rings of partial flag varieties and their associated unipotent radicals. These structures are shown to be quantizations of the cluster algebra structures found on the corresponding classical objects by Geiss, Leclerc an

Mohammad El Smaily

The goal of this paper is to find the homogenized equation of a heterogenous Fisher-KPP model in a periodic medium. The solutions of this model are pulsating travelling fronts whose \emph{speeds} are superior to a parametric minimal speed $c^*_L$. We first find the homogenized limit of the stationary states which depend on the space variable in many cases. T

Dmitri Shakhmatov, Jan Spěvák

We denote by C_p(X,G) the group of all continuous functions from a space X to a topological group G endowed with the topology of pointwise convergence. We say that spaces X and Y are G-equivalent provided that the topological groups C_p(X,G) and C_p(Y,G) are topologically isomorphic. We investigate which topological properties are preserved by G-equivalence,

N. Grau

Jets at the LHC are expected to provide the testing ground for studying QCD energy loss. In this contribution, we briefly outline the strategy that will be used to measure jets in ATLAS and how we will go about studying energy loss. We describe the utility of measuring the jet $R_{AA}$, the fragmentation function, and heavy flavor jets. Utilizing the collisi

Yuri V. Kovchegov

We review two different theoretical approaches to the strong interaction dynamics at the early times immediately following heavy ion collisions. One approach is based on small-coupling physics of the Color Glass Condensate (CGC). The other approach is based on Anti-de Sitter space/Conformal Field Theory (AdS/CFT) correspondence and may be applicable to descr

Nikolai Nikitin, Konstantin Toms

We present a relativistic generalization of the Wigner inequality for the scalar and pseudoscalar particles decaying to two particles with spin (fermions and photons.) We consider Wigner&#39;s inequality with the full spin anticorrelation (with the non-relativistic analog) as well as the case with the full spin correlation. The latter case may be obtained by

Shunsuke Tsuchioka

Brundan and Kleshchev showed that some parts of the representation theory of the affine Hecke-Clifford superalgebras and its finite-dimensional &#34;cyclotomic&#34; quotients are controlled by the Lie theory of type $A^{(2)}_{2l}$ when the quantum parameter $q$ is a primitive $(2l+1)$-th root of unity. We show in this paper that similar theorems hold when $q

Michał Hanasz, Dominik Wóltański, Kacper Kowalik

We report first results of first global galactic-scale CR-MHD simulations of cosmic-ray-driven dynamo. We investigate the dynamics of magnetized interstellar medium (ISM), which is dynamically coupled with the cosmic-ray (CR) gas. We assume that exploding stars deposit small-scale, randomly oriented, dipolar magnetic fields into the differentially rotating I

E. Aldo Arroyo

We evaluate the tachyon potential in the Schnabl gauge through off-shell computations in the sliver frame. As an application of the results of our computations, we provide a strong evidence that Schnabl&#39;s analytic solution for tachyon condensation in open string field theory represents a saddle point configuration of the full tachyon potential. Additiona

Masanori Hanada, Lorenzo Mannelli, Yoshinori Matsuo

Using the Eguchi-Kawai equivalence, we provide regularizations of supersymmetric quiver and Chern-Simons gauge theories which leave the supersymmetries unbroken. This allow us to study many interesting theories on a computer. As examples we construct large-$N$ reduced models of supersymmetric QCD with flavor and the ABJM model of multiple M2 branes.

Elena Bruna

Measurements of inclusive hadron suppression and di-hadron azimuthal correlations have provided important insights into jet quenching in hot QCD matter. However, they do not provide access to the energy of the hard scattering and are limited in their sensitivity since they can be affected by biases toward hard fragmentation and small energy loss. Full jet re

George S. F. Stephans

Data from the PHOBOS detector have been used to study two-particle correlations over a broad range of pseudorapidity. A simple cluster model parameterization has been applied to inclusive two-particle correlations over a range of centrality for both Cu+Cu and Au+Au collisions at sqrt(s_NN)=200GeV. Analysis of the data for Au+Au has recently been extended to

Michel Weber

In the first part of this expository paper, we present and discuss the interplay of Dirichlet polynomials in some classical problems of number theory, notably the Lindel\"of Hypothesis. We review some typical properties of their means and continue with some investigations concerning their supremum properties. Their random counterpart is considered in the las

Michel Weber

We show a general lower bound for Mean-value of Dirichlet polynomials

Mauro Paternostro, Gerardo Adesso, Steve Campbell

We draw an explicit connection between the statistical properties of an entangled two-mode continuous variable (CV) resource and the amount of entanglement that can be dynamically transferred to a pair of non-interacting two-level systems. More specifically, we rigorously reformulate entanglement transfer process by making use of covariance matrix formalism.

Anne M. Sickles

Identified particles have long been of great interest at RHIC in large part because of the baryon/meson differences observed at intermediate $p_T$ and the implications for hadronization via quark coalescence. With recent high statistics data identified particles are also now central to understanding the details of the jet-medium interactions and energy loss

Takahiro Sagawa, Masahito Ueda

The Jarzynski equality is generalized to situations in which nonequilibrium systems are subject to a feedback control. The new terms that arise as a consequence of the feedback describe the mutual information content obtained by measurement and the efficacy of the feedback control. Our results lead to a generalized fluctuation-dissipation theorem that reflec

Tomas Brauner, Kenji Fukushima, Yoshimasa Hidaka

We discuss the phase structure of quantum chromodynamics (QCD) with two colors and two flavors of light quarks. This is motivated by the increasing interest in the QCD phase diagram as follows: (1) The QCD critical point search has been under intensive dispute and its location and existence suffer from uncertainty of effective U(1)_A symmetry restoration. (2

Daniel Smertnig

For a finite abelian group $G$ and a splitting field $K$ of $G$, let $d(G, K)$ denote the largest integer $l \in \N$ for which there is a sequence $S = g_1 \cdot ... \cdot g_l$ over $G$ such that $(X^{g_1} - a_1) \cdot ... \cdot (X^{g_l} - a_l) \ne 0 \in K[G]$ for all $a_1, ..., a_l \in K^{\times}$. If $D(G)$ denotes the Davenport constant of $G$, then there

Faisal A. A. El-Orany, Wahiddin M. R. B., Mustafa Afanddi Mat Nor, Norziana Jamil

In this paper, we develop a quantum key distribution protocol based on the Greenberger-Horne-Zeilinger states (GHZs). The particles are exchanged among the users in blocks through two steps. In this protocol, for three-particle GHZs three keys can be simultaneously generated. The advantage of this is that the users can select the most suitable key for commun

Jaromir Tosiek

The Fedosov deformation quantization on a cotangent bundle with a symplectic connection induced by some linear symmetric connection on the base space is considered. A global construction of the symplectic homogeneous connection on the cotangent bundle modelled on the linear symmetric connection from the base space is proposed. Examples of the induced symplec

E. Androulaki, S. Lambropoulou, I. G. Economou, J. H. Przytycki

In this paper we give a method for constructing systematically all simple 2-connected graphs with n vertices from the set of simple 2-connected graphs with n-1 vertices, by means of two operations: subdivision of an edge and addition of a vertex. The motivation of our study comes from the theory of non-ideal gases and, more specifically, from the virial equa

S. Becker, F. Grüner, D. Habs

Laser-plasma accelerators are expected to deliver electron bunches with high space charge fields. Several recent publications have addressed the impact of space charge effects on such bunches after the extraction into vacuum. Artifacts due to the approximation of retardation effects are addressed, which are typically either neglected or approximated. We disc

Takahiro Hasebe, Hayato Saigo

In the present paper we define the notion of generalized cumulants which gives a universal framework for commutative, free, Boolean, and especially, monotone probability theories. The uniqueness of generalized cumulants holds for each independence, and hence, generalized cumulants are equal to the usual cumulants in the commutative, free and Boolean cases. T

A. Font, L. E. Ibanez

We study the local structure of zero mode wave functions of chiral matter fields in F-theory unification. We solve the differential equations for the zero modes derived from local Higgsing in the 8-dimensional parent action of F-theory 7-branes. The solutions are found as expansions both in powers and derivatives of the magnetic fluxes. Yukawa couplings are

Steven Finch

The average number of primitive quadratic Dirichlet characters of modulus n tends to a constant as n->infty. The same is true for primitive cubic characters. It is therefore surprising that, as n->infty, the average number of primitive quartic characters of modulus n grows with ln(n), and that the average number of primitive octic characters of modulus n gro

Ganna Rozhnova, Ana Nunes

In this paper, we consider a simple stochastic epidemic model on large regular random graphs and the stochastic process that corresponds to this dynamics in the standard pair approximation. Using the fact that the nodes of a pair are unlikely to share neighbors, we derive the master equation for this process and obtain from the system size expansion the powe

Bijan Bagchi, Atreyee Sinha

We examine the possible trajectories of a classical particle, trapped in a two-dimensional infinite rectangular well, using the Hamilton-Jacobi equation. We observe that three types of trajectories are possible: periodic orbits, open orbits and some special trajectories when the particle gets pocketed.

S. Rosswog

We present and test a new, special-relativistic formulation of Smoothed Particle Hydrodynamics (SPH). Our approach benefits from several improvements with respect to earlier relativistic SPH formulations. It is self-consistently derived from the Lagrangian of an ideal fluid and accounts for special-relativistic &#34;grad-h terms&#34;. In our approach, we evo

Heesung Shin, Jiang Zeng

A {\em pointed partition} of $n$ is a pair $(\lambda, v)$ where $\lambda\vdash n$ and $v$ is a cell in its Ferrers diagram. We construct an involution on pointed partitions of $n$ exchanging "hook length" and "part length". This gives a bijective proof of a recent result of Bessenrodt and Han.

Xiao-Bo Dong, Ting-Gui Wang, Jian-Guo Wang, Xiaohui Fan

We have investigated the ensemble regularities of the equivalent widths (EWs) of MgII 2800 emission line of active galactic nuclei (AGNs), using a uniformly selected sample of 2092 Seyfert 1 galaxies and quasars at 0.45 <= z <= 0.8 in the spectroscopic data set of Sloan Digital Sky Survey Fourth Data Release. We find a strong correlation between the EW of Mg

Qingfeng Zhu, Ben Davies, Donald F. Figer, Christine Trombley

We present a multi-wavelength photometric and spectroscopic study of a newly discovered candidate cluster [DBS2003] 45. Our H, Ks photometry confirms that [DBS2003] 45 is a cluster. An average visual extinction Av 7.1+/-0.5 is needed to fit the cluster sequence with a model isochrone. Low resolution spectroscopy indicates that half a dozen early B and at lea

Valérie Berthé, Anne Siegel, Wolfgang Steiner, Paul Surer

Shift radix systems form a collection of dynamical systems depending on a parameter $\mathbf{r}$ which varies in the $d$-dimensional real vector space. They generalize well-known numeration systems such as beta-expansions, expansions with respect to rational bases, and canonical number systems. Beta-numeration and canonical number systems are known to be int

K. P. Naveen, A. Kumar

We consider a wireless sensor network whose main function is to detect certain infrequent alarm events, and to forward alarm packets to a base station, using geographical forwarding. The nodes know their locations, and they sleep-wake cycle, waking up periodically but not synchronously. In this situation, when a node has a packet to forward to the sink, ther

Denis Belomestny

The problem of estimating the Lévy density of a partially observed multidimensional affine process from low-frequency and mixed-frequency data is considered. The estimation methodology is based on the log-affine representation of the conditional characteristic function of an affine process and local linear smoothing in time. We derive almost sure uniform rat

Xicheng Zhang

In this article we study (possibly degenerate) stochastic differential equations (SDE) with irregular (or discontiuous) coefficients, and prove that under certain conditions on the coefficients, there exists a unique almost everywhere stochastic (invertible) flow associated with the SDE in the sense of Lebesgue measure. In the case of constant diffusions and

A. Adelmann, P. Arbenz, Y. Ineichen

We discuss the scalable parallel solution of the Poisson equation within a Particle-In-Cell (PIC) code for the simulation of electron beams in particle accelerators of irregular shape. The problem is discretized by Finite Differences. Depending on the treatment of the Dirichlet boundary the resulting system of equations is symmetric or `mildly&#39; nonsymmet

J. Grube

We present long-term observations of several VHE (E > 100 GeV) blazars with VERITAS, together with contemporaneous Swift and RXTE X-ray data. The observed targets include Mrk 421, Mrk 501, 1ES 2344+514. Strong flux and spectral variability is seen in Mrk 421 on nightly time-scales between January and June 2008, revealing a highly correlated X-ray to GeV/TeV

Mehdi Nadjafikhah, Rohollah Bakhshandeh-Chamazkoti, Ali Mahdipour-Shirayeh

In this paper, a symmetry classification of a $(2+1)$-nonlinear wave equation $u_{tt}-f(u)(u_{xx}+u_{yy})=0$ where $f(u)$ is a smooth function on $u$, using Lie group method, is given. The basic infinitesimal method for calculating symmetry groups is presented, and used to determine the general symmetry group of this $(2+1)$-nonlinear wave equation.

E. Carretti, M. Haverkorn, D. McConnell, G. Bernardi

We present observations and CMB foreground analysis of the Parkes Galactic Meridian Survey (PGMS), an investigation of the Galactic latitude behaviour of the polarized synchrotron emission at 2.3 GHz with the Parkes Radio Telescope. The survey consists of a 5-deg wide strip along the Galactic meridian l=254-deg extending from Galactic plane to South Galactic

Rostand Tayong, Thomas Dupont, Philippe Leclaire

The acoustic behavior of micro-perforated panels (MPP) is studied theoretically and experimentally at high level of pressure excitation. A model based on Forcheimer&#39;s regime of flow velocity in the perforations is proposed. This model is valid at relatively high Reynolds numbers and low Mach numbers. The experimental method consists in measuring the acou

Y. M. Niquet, L. Genovese, C. Delerue, T. Deutsch

We discuss the binding energy E_b of impurities in semiconductors within density functional theory (DFT) and the GW approximation, focusing on donors in nanowires as an example. We show that DFT succeeds in the calculation of E_b from the Kohn-Sham (KS) hamiltonian of the ionized impurity, but fails in the calculation of E_b from the KS hamiltonian of the ne

Katherine Jones-Smith, Lawrence M. Krauss, Harsh Mathur

Inflation produces super-horizon sized perturbations that ultimately return within the horizon and are thought to form the seeds of all observed large scale structure in the Universe. But inflationary predictions can only be compared with present day observations if, as conventional wisdom dictates, they remain unpolluted by subsequent sub-horizon causal phy

Mate Csanad

Ultra-peripheral collisions (UPC) of heavy-ions involve long range electromagnetic interactions at impact parameters twice larger than the nuclear radius, where no nucleon-nucleon collisions occur. The first measurement of photoproduction of $J/\psi$ and of two-photon production of high-mass $e^+ e^-$ pairs in ultra-peripheral nucleus-nucleus interactions wi

Sela Samin, Yoav Tsori

We consider the influence of electric field gradients on the phase behavior of nonpolar binary mixtures. Small fields give rise to smooth composition profiles, whereas large enough fields lead to a phase-separation transition. The critical field for demixing as well as the equilibrium phase separation interface are given as a function of the various system p

Anirudh Pradhan, Shyam Sundar Kumhar, Padmini Yadav, Kanti Jotania

A new class of LRS Bianchi type ${\rm VI}_{0}$ cosmological models with free gravitational fields and a variable cosmological term is investigated in presence of perfect fluid as well as bulk viscous fluid. To get the deterministic solution we have imposed the two different conditions over the free gravitational fields. In first case we consider the free gra

Laurent Bonavero, Andreas Höring

Let X be a projective manifold containing a quasi-line l. An important difference between quasi-lines and lines in the projective space is that in general there is more than one quasi-line passing through two given general points. In this paper we use this feature to construct an algebraic foliation associated to a family of quasi-lines. We prove that if the

Thomas Timmermann

We introduce a relative tensor product of $C^{*}$-modules and a spatial fiber product of $C^{*}$-algebras that are analogues of Connes&#39; fusion of correspondences and the fiber product of von Neumann algebras introduced by Sauvageot, respectively, and study their categorical properties. These constructions form the basis for our approach to quantum groupo

Derek Teaney

I review the recent progress in measuring elliptic flow in heavy ion collisions. These measurements show clearly how hydrodynamics starts to develop as the system size is increased from peripheral to central collisions. During this transition, the momentum range described by hydrodynamics increases as the system progresses from a kinetic to a hydrodynamic re