January 2009 arXiv papers — page 18

L. Teriaca, W. Curdt, S. K. Solanki

Aims. We analyse SUMER spectral scans of a large sunspot within active region NOAA 10923, obtained on 14-15 November 2006, to determine the morphology and dynamics of the sunspot atmosphere at different heights/temperatures. Methods: The data analysed here consist of spectroheliograms in the continuum around 142.0 nm and in the Si iv 140.2 nm, O iii 70.3 nm,

A. Deltuva

Direct nuclear reactions $\vec{d}+A$ and $\vec{p}+(An)$ are described in the framework of three-body Faddeev-type equations. Differential cross section and analyzing powers are calculated using several optical potential models and compared with the experimental data. Quite satisfactory agreement is found except for few systematic discrepancies.

R. D. Young, A. W. Thomas

We report an analysis of the impressive new lattice simulation results for octet baryon masses in 2+1-flavor QCD. The analysis is based on a low order expansion about the chiral SU(3) limit in which the symmetry breaking arises from terms linear in the quark masses plus the variation of the Goldstone boson masses in the leading chiral loops. The baryon masse

V. K. Magas, E. Oset, A. Ramos

We analyze the peaks in the (Lambda p) and (Lambda d) invariant mass distributions, observed in recent FINUDA experiments and claimed to be signals of deeply bound kaonic states, and find them to be naturally explained in terms of K- absorption by two or three nucleons leaving the rest of the original nuclei as spectator. For reactions on heavy nuclei, the s

Yuehong Xie

Miminizing errors of the physical parameters of interest should be the ultimate goal of any event selection optimization in high energy physics data analysis involving parameter determination. Quick and reliable error estimation is a crucial ingredient for realizing this goal. In this paper we derive a formalism for direct evaluation of measurement errors us

Matthias Vojta

This article will give an overview on both theoretical and experimental developments concerning states with lattice symmetry breaking in the cuprate high-temperature superconductors. Recent experiments have provided evidence for states with broken rotation as well as translation symmetry, and will be discussed in terms of nematic and stripe physics. Of parti

Michel Dekking, Károly Simon, Balázs Székely

In this paper, we consider a family of random Cantor sets on the line and consider the question of whether the condition that the sum of the Hausdorff dimensions is larger than one implies the existence of interior points in the difference set of two independent copies. We give a new and complete proof that this is the case for the random Cantor sets introdu

Isabelle Bouchoule, N. J. Van Druten, Christoph I. Westbrook

In this review article, we describe the studies of 1D gases realised on atom-chip experiments.

C. M. Chaves, A. A. Gomes, A. Troper

The magnetic properties of pure transition-like metals are discussed within the single site approximation, to take into account the electron correlation. The metal is described by two hybridized bands one of which includes the Coulomb correlation. Our results indicate that ferromagnetism follows from adequate values of the correlation and hybridization.

Leo van Iersel, Matthias Mnich

A chief problem in phylogenetics and database theory is the computation of a maximum consistent tree from a set of rooted or unrooted trees. A standard input are triplets, rooted binary trees on three leaves, or quartets, unrooted binary trees on four leaves. We give exact algorithms constructing rooted and unrooted maximum consistent supertrees in time O(2^

N. Cundy, M. Göckeler, R. Horsley, T. Kaltenbrunner

We discuss a 3-flavour lattice QCD action with clover improvement in which the fermion matrix has single level stout smearing for the hopping terms together with unsmeared links for the clover term. With the (tree-level) Symanzik improved gluon action this constitutes the Stout Link Non-perturbative Clover or SLiNC action. To cancel O(a) terms the clover ter

Luce Prignano, Maurizio Serva

In a population with haploid reproduction any individual has a single parent in the previous generation. If all genealogical distances among pairs of individuals (generations from the closest common ancestor) are known it is possible to exactly reconstruct their genealogical tree. Unfortunately, in most cases, genealogical distances are unknown and only gene

Brendan M Jackson, Andy Taylor, Arjun Berera

Recently, Valiviita et al. (2008) have reported a large-scale early-time instability in coupled dark energy and dark matter models. We take the same form of energy-momentum exchange and specialise to the case when the interaction rate is proportional to Hubble's parameter and the dark energy density only. Provided the coupling is made small enough for a

Simon Heimlicher, Merkouris Karaliopoulos, Hanoch Levy, Thrasyvoulos Spyropoulos

Mobile wireless network research focuses on scenarios at the extremes of the network connectivity continuum where the probability of all nodes being connected is either close to unity, assuming connected paths between all nodes (mobile ad hoc networks), or it is close to zero, assuming no multi-hop paths exist at all (delay-tolerant networks). In this paper,

Theja N. De Silva

We study s-wave pairing of population imbalanced Fermi atoms in quasi two dimensions using a mean field theory. At zero temperature, we map out the phase diagram in the entire Bardeen, Cooper and Schrieffer-Bose Einstein condensation (BCS-BEC) crossover region by investigating the effect of weak atom tunneling between layers. We find that the superfluid phas

Jani Lukkarinen, Herbert Spohn

It is common practice to approximate a weakly nonlinear wave equation through a kinetic transport equation, thus raising the issue of controlling the validity of the kinetic limit for a suitable choice of the random initial data. While for the general case a proof of the kinetic limit remains open, we report on first progress. As wave equation we consider th

S. Lipari, M. Bergmann, S. F. Sanchez, B. Garcia-Lorenzo

From a study of BAL + IR + Fe II QSOs (using deep Gemini GMOS-IFU spectroscopy) new results are presented: for IRAS 04505-2958. Specifically, we have studied in detail the out flow (OF) process and their associated structures, mainly at two large galactic scales: (i) two blobs/shells (S1, S2) at radius r = 1.1 and 2.2 kpc; and (ii) an external hypergiant she

Chia-Min Lin, Kingman Cheung

Supernatural inflation is an attractive model based just on a flat direction with soft SUSY breaking mass terms in the framework of supersymmetry. The beauty of the model is inferred from its name that the model needs no fine-tuning. However, the prediction of the spectral index is $n_s \gae 1$, in contrast to experimental data. In this paper, we show that t

Dongho Chae

In this paper we prove the nonexistence of global weak solutions to the compressible Navier-Stokes equations for the isentropic gas in $\Bbb R^N, N\geq 3,$ where the pressure law given by $p(ρ)=aρ^γ, $ $a>0, 1<γ\leq \frac{N}{4}+\frac12$. In this case if the initial data satisfies $\int_{\Bbb R^N} ρ_0 (x)v_0 (x)\cdot x dx >0$, then there exists no finite ener

J. Hartlap, T. Schrabback, P. Simon, P. Schneider

(abridged) We study the validity of the approximation of a Gaussian cosmic shear likelihood. We estimate the true likelihood for a fiducial cosmological model from a large set of ray-tracing simulations and investigate the impact of non-Gaussianity on cosmological parameter estimation. We investigate how odd the recently reported very low value of $σ_8$ real

M. Errando, R. Bock, D. Kranich, E. Lorenz

3C 279 is one of the best studied flat spectrum radio quasars located at a comparatively large redshift of z = 0.536. Observations in the very high energy band of such distant sources were impossible until recently due to the expected steep energy spectrum and the strong gamma-ray attenuation by the extragalactic background light photon field, which conspire

Michel Bergère, Bertrand Eynard

We prove that the correlations functions, generated by the determinantal process of the Christoffel-Darboux kernel of an arbitrary order 2 ODE, do satisfy loop equations.

Tomasz Sowinski

Properties of a two-level atom coupled to the quantized electromagnetic field at finite temperature are determined. The analysis is based on a new method (inspired by QED) of describing qubits, developed previously at zero temperature (Phys. Rev. A 76, 062106 (2007)). In this paper, we make a generalization to finite temperature by introducing the Matsubara

Zuo-Hong Li, Ying Li, Hong-Xia Xu

We make an evaluation of the lepton flavor violating (LFV) decays $τ\to \ell (V^0, P^0)$, where $\ell=e$ or $μ$ and $V^0(P^0)$ is a neutral vector (pseudo-scalar) meson, in the context of unparticle physics. The constraints are investigated systematically on the related coupling parameters from all the available experimental data, and the parameter values ar

Giorgio Ferrarese, Margherita Roggero

The paper concerns the affine varieties that are homogeneous with respect to a (non-standard) graduation over the group Z^m. Among the other properties it is shown that every such a variety can be embedded in its Zariski tangent space at the origin, so that it is smooth if and only if it is isomorphic to an affine space. The results directly apply to the stu

Ilja Schmelzer

In the many worlds community seems to exist a belief that the physics of a quantum theory is completely defined by it&#39;s Hamilton operator given in an abstract Hilbert space, especially that the position basis may be derived from it as preferred using decoherence techniques. We show, by an explicit example of non-uniqueness, taken from the theory of the K

Uma Divakaran, Amit Dutta

We present an exact result for the non-adiabatic transition probability and hence the defect density in the final state of a one-dimensional Kitaev model following a slow quench of the parameter $J_-$, which estimates the anisotropy between the interactions, as $J_-(t)\sim -|t/τ|$. Here, time $t$ goes from $-\infty$ to $+\infty$ and $τ$ defines the rate of c

A. V. Syromyatnikov

It is well-known that in thin ferromagnetic film with a net magnetization perpendicular to the film the collinear arrangement of spins is unstable in an in-plane field $H$ smaller than its saturation value $H_c$. Existence of a stripe phase was proposed with elongated domains of alternating direction of magnetization component perpendicular to the film. We c

Surajit Sen, Mihir Ranjan Nath, Tushar Kanti Dey, Gautam Gangopadhyay

The cascade, lambda and vee type of three-level systems are shown to be described by three different Hamiltonians in the SU(3) basis. We investigate the Bloch space structure of each configuration by solving the corresponding Bloch equation and show that at resonance, the seven-dimensional Bloch sphere ${\mathcal S}^7$ is broken into two distinct subspaces $

Alexandre M. Santos, Prafulla K. Panda, Constança Providência

In the present work we include the isovector-scalar $\delta$-meson in the quark-meson coupling model (QMC) and study the properties of asymmetric nuclear within QMC without and with the $\delta$-meson. Recent constraints set by isospin diffusion on the slope parameter of the nuclear symmetry energy at saturation density are used to adjust the model parameter

Massimo Gobbino, Robert Samuel Simon

Let C be a closed subset of a topological space X, and let f : C --> X. Let us assume that f is continuous and f(x) lies in C for every x in the boundary of C. How many times can one iterate f? This paper provides estimates on the number of iterations and examples of their optimality. In particular we show how some topological properties of f, C, X are relat

Serena Bradde, Ginestra Bianconi

In this work, we study the percolation transition and large deviation properties of generalized canonical network ensembles. This new type of random networks might have a very rich complex structure, including high heterogeneous degree sequences, non-trivial community structure or specific spatial dependence of the link probability for networks embedded in a

Shuai Jiang, Hui Xing, Guofang Xuan, Cao Wang

We report bulk superconductivity induced by an isovalent doping of phosphorus in BaFe$_{2}$(As$_{1-x}$P$_{x}$)$_{2}$. The P-for-As substitution results in shrinkage of lattice, especially for the FeAs block layers. The resistivity anomaly associated with the spin-density-wave (SDW) transition in the undoped compound is gradually suppressed by the P doping. S

Shinji Tsujikawa, Takashi Tamaki, Reza Tavakol

We study the field profile of a scalar field $ϕ$ that couples to a matter fluid (dubbed a chameleon field) in the relativistic gravitational background of a spherically symmetric spacetime. Employing a linear expansion in terms of the gravitational potential $Φ_c$ at the surface of a compact object with a constant density, we derive the thin-shell field prof

Viet-Anh Nguyen

In the previous version of this paper we prove a theorem on the boundary behavior of the conical plurisubharmonic measure. However, the proof turns out to be incomplete. In the present version we give a corrected proof of this theorem. We next apply it to the theory of separately holomorphic functions. These applications are presented in a more accessible wa

Ion I. Cotaescu

The quantum theory of the vector field minimally coupled to the gravity of the de Sitter spacetime is built in a canonical manner starting with a new complete set of quantum modes of given momentum and helicity derived in the moving chart of conformal time. It is shown that the canonical quantization leads to new vector propagators which satisfy similar equa

Danny Bickson, Alexander T. Ihler, Danny Dolev

The recent work of Sommer, Feder and Shalvi presented a new family of codes called low density lattice codes (LDLC) that can be decoded efficiently and approach the capacity of the AWGN channel. A linear time iterative decoding scheme which is based on a message-passing formulation on a factor graph is given. In the current work we report our theoretical fin

Farzan Haddadi, Mohammadreza Malekmohammadi, Mohammad Mahdi Nayebi, Mohammad Reza Aref

In this correspondence, we focus on the performance analysis of the widely-used minimum description length (MDL) source enumeration technique in array processing. Unfortunately, available theoretical analysis exhibit deviation from the simulation results. We present an accurate and insightful performance analysis for the probability of missed detection. We a

Spyros Basilakos

We study the dynamics of the FLRW flat cosmological models in which the vacuum energy density varies with time, $Λ(t)$. In particular, we investigate the dynamical properties of a generalized vacuum model and we find that under certain conditions the vacuum term in the radiation era varies as $Λ(z) \propto (1+z)^{4}$, while in the matter era we have $Λ(z)\pr

V. F. Cardone, S. Capozziello, M. G. Dainotti

Gamma ray bursts (GRBs) have recently attracted much attention as a possible way to extend the Hubble diagram to very high redshift. To this aim, the luminosity (or isotropic emitted energy) of a GRB at redshift z must be evaluated from a correlation with a distance independent quantity so that one can then solve for the luminosity distance D_L(z) and hence

Amit Verma, Anirban Pathak

A generalized notion of higher order nonclassicality (in terms of higher order moments) is introduced. Under this generalized framework of higher order nonclassicality, conditions of higher order squeezing and higher order subpoissonian photon statistics are derived. A simpler form of the Hong-Mandel higher order squeezing criterion is derived under this fra

Mahmood Roshan, Maryam Nouri, Fatimah Shojai

We consider scalar-tensor theory for describing varying speed of light in a spatially flat FRW space-time. We find some exact solutions in the metric and Palatini formalisms. Also we examine the dynamics of this theory by dynamical system method assuming a $Λ$CDM background and we find some exact solutions by considering the character of critical points of t

Gerardo Adesso

We demonstrate that the entanglement in a class of two-mode non-Gaussian states obtained by subtracting photons from Gaussian twin beams can be bounded from above and from below by functionals of the second moments only. Knowledge of the covariance matrix thus suffices for an entanglement quantification with appreciable precision. The absolute error in the e

Arya Mazumdar, Ron M. Roth, Pascal O. Vontobel

Let n be an even positive integer and F be the field \GF(2). A word in F^n is called balanced if its Hamming weight is n/2. A subset C \subseteq F^n$ is called a balancing set if for every word y \in F^n there is a word x \in C such that y + x is balanced. It is shown that most linear subspaces of F^n of dimension slightly larger than 3/2\log_2(n) are balanc

Jie-Jun Tseng, Ming-Jer Lee, Sai-Ping Li

Human activities can play a crucial role in the statistical properties of observables in many complex systems such as social, technological and economic systems. We demonstrate this by looking into the heavy-tailed distributions of observables in fatal plane and car accidents. Their origin is examined and can be understood as stochastic processes that are re

Alireza Abdollahi

In this paper we study the longstanding conjecture of whether there exists a noninner automorphism of order $p$ for a finite non-abelian $p$-group. We prove that if $G$ is a finite non-abelian $p$-group such that $G/Z(G)$ is powerful then $G$ has a noninner automorphism of order $p$ leaving either $Φ(G)$ or $Ω_1(Z(G))$ elementwise fixed. We also recall a con

H. Kobayashi, Y. Fukumoto, A. Oguchi

A frustrated Ising model on a diamond hierarchical lattice is studied. We obtain the exact partition function of this model and calculate the transition temperature, specific heat, entropy, magnetization, and ferromagnetic correlation function. Depending on the magnitude of a parameter giving the frustration, there exist three types of ground states: ferroma

Vijay Kodiyalam, V. S. Sunder

We analyse the Guionnet-Jones-Shlyakhtenko construction for the planar algebra associated to a finite-dimensional Kac algebra and identify the factors that arise as finite interpolated free group factors.

Ural Bekbaev

In this paper polynomial maps are represented by the use of matrices whose entries are numbered by pair of multiindices and a new product of such matrices is introduced. A matrix representation of composition of polynomial maps is given. In the case of real and complex numbers different kind of norms of such matrices are introduced. Properties of these norms

Shuji Nakamura, Masayuki Hashisaka, Yoshiaki Yamauchi, Shinya Kasai

We report an experimental study on the shot noise as well as the dc transport properties of a quantum point contact (QPC) whose conductance anomaly can be tuned electrostatically by the gate electrodes. By controlling the single QPC so that it has no anomaly or an anomaly at $0.5 G_0$, $0.8 G_0$ or $0.9 G_0$ ($G_0 = 2e^2/h$), we prove that the anomaly always

Fei Li, Yifeng Xue

We define zonal polynomials of quaternion matrix argument and deduce some important formulae of zonal polynomials and hypergeometric functions of quaternion matrix argument. As an application, we give the distributions of the largest and smallest eigenvalues of a quaternion central Wishart matrix $W\sim\mathbb{Q}W(n,Σ)$, respectively.

Davide a Marca, Stefano Beltraminelli, Danilo Merlini

In this note we discuss explicitly the structure of two simple set of zeros which are associated with the mean staircase emerging from the zeta function and we specify a solution using the Lambert W function. The argument of it may then be set equal to a special $N \times N$ classical matrix (for every $N$) related to the Hamiltonian of the Mehta-Dyson model

Juan A. Almendral, Joao G. Oliveira, L. López, J. F. F. Mendes

We use the emergent field of Complex Networks to analyze the network of scientific collaborations between entities (universities, research organizations, industry related companies,...) which collaborate in the context of the so-called Framework Programme. We demonstrate here that it is a scale--free network with an accelerated growth, which implies that the

V. Smolcic, G. Zamorani, E. Schinnerer, S. Bardelli

We explore the cosmic evolution of radio AGN with low radio powers (L_1.4GHz < 5\times10^25 W/Hz) out to z=1.3 using to-date the largest sample of ~600 low luminosity radio AGN at intermediate redshift drawn from the VLA-COSMOS survey. We derive the radio luminosity function for these AGN, and its evolution with cosmic time assuming two extreme cases: i) pur

Eric Gaidos, Alexander N. Krot, Jonathan P. Williams, Sean N. Raymond

In agreement with previous work, we show that the presence of the short-lived radionuclide Al-26 in the early Solar System was unlikely (<2% a priori probability) to be the result of direct introduction of supernova ejecta into the gaseous disk during the Class II stage of protosolar evolution. We also show that any Bondi-Hoyle accretion of contaminated resi

Jacob Linder, Malek Zareyan, Asle Sudbø

We present an analytical study of the proximity effect in ferromagnet/superconductor (F/S) heterostructures, allowing for an arbitrary magnetic exchange energy as well as arbitrary impurity and spin-flip scattering rates within a quasiclassical approach. While previous studies mainly have focused on the clean or dirty limits, our results grant access to the

Panagiotis Labropoulos, Leon V. E. Koopmans, Vibor Jelic, Sarod Yatawatta

A number of experiments are set to measure the 21-cm signal of neutral hydrogen from the Epoch of Reionization (EoR). The common denominator of these experiments are the large data sets produced, contaminated by various instrumental effects, ionospheric distortions, RFI and strong Galactic and extragalactic foregrounds. In this paper, the first in a series,

S. S. Pankratov, E. E. Saperstein, M. V. Zverev, M. Baldo

Spatial correlation characteristics of the anomalous density matrix $κ$ in a slab of nuclear matter with the Paris and Argonne v18 forces are calculated. A detailed comparison with predictions of the effective Gogny force is made. It is found that the two realistic forces lead to very close results which are qualitatively similar to those for the Gogny force

E. Torresi, P. Grandi, M. Guainazzi, G. G. C. Palumbo

All the observations available in the Chandra and XMM-Newton archives have been used to investigate the X-ray spectral properties of 3C 33. In this paper is presented a complete X-ray analysis of the nuclear emission of this narrow line radio galaxy. The broad band spectrum of 3C 33 is complex. The hard part resembles that of Seyfert 2 galaxies, with a heavi

J. Martin Laming

We revisit in more detail a model for element abundance fractionation in the solar chromosphere, that gives rise to the &#34;FIP Effect&#34; in the solar corona and wind. Elements with first ionization potential below about 10 eV, i.e. those that are predominantly ionized in the chromosphere, are enriched in the corona by a factor 3-4. We model the propagati

C. Chryssomalakos, H. Hernandez-Coronado, E. Okon

In this contribution, we suggest the approach that geometric concepts ought to be defined in terms of physical operations involving quantum matter. In this way it is expected that some (presumably nocive) idealizations lying deep within the roots of the notion of spacetime might be excluded. In particular, we consider that spacetime can be probed only with p

Brendan Ames, Stephen Vavasis

We consider the problems of finding a maximum clique in a graph and finding a maximum-edge biclique in a bipartite graph. Both problems are NP-hard. We write both problems as matrix-rank minimization and then relax them using the nuclear norm. This technique, which may be regarded as a generalization of compressive sensing, has recently been shown to be an e

Gerd Bergmann

The electronic properties of a Kondo impurity are investigated in a magnetic field using linear response theory. The distribution of electrical charge and magnetic polarization are calculated in real space. The (small) magnetic field does not change the charge distribution. However, it unmasks the Kondo cloud. The (equal) weight of the d-electron components

Dan Yasaki

Let z be a primitive fifth root of unity and let F be the cyclotomic field F=Q(z). Let O be the ring of integers. We compute the Voronoi polyhedron of binary Hermitian forms over F and classify GL_2(O)-conjugacy classes of perfect forms. The combinatorial data of this polyhedron can be used to compute the cohomology of the arithmetic group GL_2(O) and Hecke

Uttam Shrestha, Juha Javanainen, Janne Ruostekoski

We study the dynamics of a Bose-Einstein condensate in a one-dimensional optical lattice in the limit of weak atom-atom interactions, including an approximate model for quantum fluctuations. A pulsating dynamical instability in which atoms periodically collect together and subsequently disperse back into the initial homogeneous state may occur in the time ev

Károly J. Böröczky, Rolf Schneider

For a given convex body K in $R^d$, a random polytope $K^{(n)}$ is defined (essentially) as the intersection of $n$ independent closed halfspaces containing $K$ and having an isotropic and (in a specified sense) uniform distribution. We prove upper and lower bounds, of optimal orders, for the difference of the mean widths of $K^{(n)}$ and K, as n tends to in

Károly J. Böröczky

A stability version of the Blaschke-Santaló inequality and the affine isoperimetric inequality for convex bodies of dimension n>2 is proved. The first step is the reduction to the case when the convex body is o-symmetric and has axial rotational symmetry. This step works for related inequalities compatible with Steiner symmetrization. Secondly, for these con

Parveen Kumar, K. Shahi

The structural and electrical characterizations of mechanically-milled (MM) amorphous fast ionic conductors (a-FICs), viz. xAgI (100-x)[0.67 Ag\_2 O-0.33V\_2O\_5] (x = 40, 50, 55 and 70) have been reported. The amorphisation is restricted only to the compositions which are well within the glass forming region and all samples are found to be highly agglomerat

Brian Dudley, Christopher Kolda

We examine the current lower bound on the charged Higgs boson mass in the Minimal Supersymmetric Standard Model. By applying direct search constraints on the neutral Higgs bosons and other supersymmetric states, as well as a number of indirect constraints (b -> s gamma, B_s -> mu mu, B -> tau nu, B -> D tau nu), we find that it is possible to push the charge

Wojciech Broniowski, Enrique Ruiz Arriola

Generalized form factors of hadrons are objects appearing in moments of the generalized parton distributions. Their leading-order DGLAP-ERBL QCD evolution is exceedingly simple and the solution is given in terms of matrix triangular structures of linear equations where the coefficients are the evolution ratios. We point out that this solution has a practical

Igor B. Mekhov, Helmut Ritsch

Quantum optics with quantum gases represents a new field, where the quantum nature of both light and ultracold matter plays equally important role. Only very recently this ultimate quantum limit of light-matter interaction became feasible experimentally. In traditional quantum optics, the cold atoms are considered classically, whereas, in quantum atom optics

James M. Rondinelli, Aaron S. Eidelson, Nicola A. Spaldin

Using first-principles density functional theory we predict a ferroelectric ground state -- driven by off-centering of the magnetic Mn$^{4+}$ ion -- in perovskite-structure BaMnO$_3$. Our finding is surprising, since the competition between energy-lowering covalent bond formation, and energy-raising Coulombic repulsions usually only favors off-centering on t

Magdalena Posiadala, for NA61, Collaboration

A precise measurement of the hadron production from interactions of 30 GeV protons on carbon target is performed by NA61 (SHINE) experiment at the CERN SPS. The inclusive spectra of pions and kaons on the carbon target obtained from NA61 measurements constrain the neutrino flux in the T2K long baseline neutrino oscillation experiment at J-PARC, Japan. The ar

Dan Preston, Pavlos Protopapas, Carla Brodley

The discovery of events in time series can have important implications, such as identifying microlensing events in astronomical surveys, or changes in a patient&#39;s electrocardiogram. Current methods for identifying events require a sliding window of a fixed size, which is not ideal for all applications and could overlook important events. In this work, we

Jeremy Williams

A class of complex Fourier Transforms of exponential functions which have all their zeros on the real line is explored from a geometric perspective. These transforms belong to the Laguerre - Polya class, and it is proved that all the zeros are simple.

Ahmad T. Ali, Rafael López

We consider a unit speed curve $α$ in Euclidean $n$-dimensional space $E^n$ and denote the Frenet frame by $\{v_1,...,v_n\}$. We say that $α$ is a cylindrical helix if its tangent vector $v_1$ makes a constant angle with a fixed direction $U$. In this work we give different characterizations of such curves in terms of their curvatures.

Ahmad T. Ali, Rafael López

We consider a unit speed curve $α$ in Euclidean four-dimensional space $E^4$ and denote the Frenet frame by $\{T,N,B_1,B_2\}$. We say that $α$ is a slant helix if its principal normal vector $N$ makes a constant angle with a fixed direction $U$. In this work we give different characterizations of such curves in terms of their curvatures.

R. Yudin, S. Hubrig, M. Pogodin, I. Savanov

We report the results of our study of magnetic fields in a sample of Be stars using spectropolarimetric data obtained at the European Southern Observatory with the multi-mode instrument FORS1 installed at the 8m Kueyen telescope. The detected magnetic fields are rather weak, not stronger than ~150G. A few classical Be stars display cyclic variability of the

Daniel Juteau, Carl Mautner, Geordie Williamson

This paper is an introduction to the use of perverse sheaves with positive characteristic coefficients in modular representation theory. In the first part, we survey results relating singularities in finite and affine Schubert varieties and nilpotent cones to modular representations of reductive groups and their Weyl groups. The second part is a brief introd

N. Pirzkal, A. J. Burgasser, S. Malhotra, B. W. Holwerda

Deep ACS slitless grism observations and identification of stellar sources are presented within the Great Observatories Origins Deep Survey (GOODS) North and South fields which were obtained in the Probing Evolution And Reionization Spectroscopically (PEARS) program. It is demonstrated that even low resolution spectra can be a very powerful means to identify

S. Hubrig, C. Grady, M. Schoeller, 0. Schuetz

We present the results of a new magnetic field survey of Herbig Ae/Be and A debris disk stars. They are used to determine whether magnetic field properties in these stars are correlated with the mass-accretion rate, disk inclinations, companion(s), Silicates, PAHs, or show a more general correlation with age and X-ray emission as expected for the decay of a

S. Hubrig, M. Briquet, P. De Cat, M. Schoeller

We present the results of the continuation of our magnetic survey with FORS1 at the VLT of a sample of B-type stars consisting of confirmed or candidate beta Cephei stars and Slowly Pulsating B stars. Roughly one third of the studied beta Cephei stars have detected magnetic fields. The fraction of magnetic Slowly Pulsating B and candidate Slowly Pulsating B

Michail Anthropelos, Gordan Zitkovic

In an incomplete semimartingale model of a financial market, we consider several risk-averse financial agents who negotiate the price of a bundle of contingent claims. Assuming that the agents&#39; risk preferences are modelled by convex capital requirements, we define and analyze their demand functions and propose a notion of a partial equilibrium price. In

Francesco Nicolò

Let an initial data metric $\overline{g}$ be, outside a ball $B_{R_0}$ centered in the origin, the induced metric on $Σ_0$ of a Kerr spacetime (with a mass $M$ and angular momentum $J$ whose ratio, $J/M$, depends on the size of $R_0$) plus small corrections which decay at spacelike infinity faster than $r^{-3}$; let, in the same region, a symmetric tensor $\

J Ben Geloun, F G Scholtz

Gazeau-Klauder coherent states in noncommutative quantum mechanics are considered. We find that these states share similar properties to those of ordinary canonical coherent states in the sense that they saturate the related position uncertainty relation, obey a Poisson distribution and possess a flat geometry. Using the natural isometry between the quantum

Amos Lapidoth, Stephan Tinguely

We study the power versus distortion trade-off for the distributed transmission of a memoryless bi-variate Gaussian source over a two-to-one average-power limited Gaussian multiple-access channel. In this problem, each of two separate transmitters observes a different component of a memoryless bi-variate Gaussian source. The two transmitters then describe th

Aijun Du, Jinqiao Duan

Complex systems display variability over a broad range of spatial and temporal scales. Some scales are unresolved due to computational limitations. The impact of these unresolved scales on the resolved scales needs to be parameterized or taken into account. One stochastic parameterization scheme is devised to take the effects of unresolved scales into accoun

Isabel Perez-Arjona, Victor Sanchez-Morcillo, Javier Redondo, Kestutis Staliunas

We study the influence of field diffusion on the spatial localized structures (cavity solitons) recently predicted in bidirectional lasers. We find twofold positive role of the diffusion: 1) it increases the stability range of the individual (isolated) solitons; 2) it reduces the long-range interaction between the cavity solitons. Latter allows the independe

C. Gabriel, J. Janousek, H. -A. Bachor

Squeezing experiments which are capable of creating a minimum uncertainty state during the nonlinear process, for example optical parametric amplification, are commonly used to produce light far below the quantum noise limit. This report presents a method with which one can characterize this minimum uncertainty state and gain valuable knowledge of the experi

Alexander S. Mishchenko, Quitzeh Morales Meléndez

We give a description of the vector $G$-bundles over $G$-spaces with quasi-free proper action of discrete group $G$ in terms of the classifying space.

S. Hubrig, M. Schoeller, R. S. Schnerr, I. Ilyin

The presence of magnetic fields in O-type stars has been suspected for a long time. The discovery of such fields would explain a wide range of well documented enigmatic phenomena in massive stars, in particular cyclical wind variability, Halpha emission variations, chemical peculiarity, narrow X-ray emission lines and non-thermal radio/X-ray emission. Here w

Ahmad idilbi, Chul Kim

We discuss the production of heavy colored paricles at the Large Hadron Collider (LHC) through gluon-gluon fusion process. A factorization theorem is obtained for this process using Soft Collinear Effective Theory. Our factorization theorem does not depend on any assumptions regarding the physics above the mass of the heavy colored particle. In this sense it

Michel Gondran

Gersten has shown how Maxwell equations can be derived from first principles, similar to those which have been used to obtain the Dirac relativistic electron equation. We show how Proca equations can be also deduced from first principles, similar to those which have been used to find Dirac and Maxwell equations. Contrary to Maxwell equations, it is necessary

Julian Moosmann

We consider spatial coarse-graining in statistical ensembles of non-selfintersecting and one-fold selfintersecting center-vortex loops as they emerge in the confining phase of SU(2) Yang-Mills thermodynamics. This coarse-graining is due to a noisy environment and described by a curve shrinking flow of center-vortex loops locally embedded in a two-dimensional

Mathew D. Penrose, Andrew R. Wade

Suppose that under the action of gravity, liquid drains through the unit $d$-cube via a minimal-length network of channels constrained to pass through random sites and to flow with nonnegative component in one of the canonical orthogonal basis directions of $\R^d$, $d \geq 2$. The resulting network is a version of the so-called minimal directed spanning tree

Victor X. Guerrero, Walter Wilcox, Joe Christensen

Using clover fermions on CP-PACS dynamical configurations, we consider a number of ways of measuring hadronic electric polarizability, an $|\mathbf{E}|^{2}$ effect in hadron masses, using lattice techniques. We consider the effects of periodic and Dirichlet boundary conditions, the field linearization postulate as well as a quantized electric field. We also

Johannes Ebert

The notion of the \emph{homotopy type} of a topological stack has been around in the literature for some time. The basic idea is that an atlas $X \to \mathfrak{X}$ of a stack determines a topological groupoid $\mathbb{X}$ with object space $X$. The homotopy type of $\mathfrak{X}$ should be the classifying space $B \mathbb{X}$. The choice of an atlas is not p

Johannes Courtial

A recent paper demonstrated that two lenslet arrays with focal lengths f_1 and f_2, separated by f_1 + f_2, change the direction of transmitted light rays approximately like the interface between isotropic media with refractive indices n_1 and n_2, where n_1 / n_2 = - f_1 / f_2 [J. Courtial, New J. Phys. 10, 083033 (2008)]. This is true if light passes throu

O. Henrich, D. Marenduzzo, K. Stratford, M. E. Cates

Here we review a hybrid lattice Boltzmann algorithm to solve the equations of motion of cholesteric liquid crystals. The method consists in coupling a lattice Boltzmann solver for the Navier-Stokes equation to a finite difference method to solve the dynamical equations governing the evolution of the liquid crystalline order parameter. We apply this method to

Stanislaw Drozdz, Jaroslaw Kwapien, Adam Orczyk

We analyze the rank-frequency distributions of words in selected English and Polish texts. We compare scaling properties of these distributions in both languages. We also study a few small corpora of Polish literary texts and find that for a corpus consisting of texts written by different authors the basic scaling regime is broken more strongly than in the c