October 2008 arXiv papers — page 32

G. R. Boyd, P. J. Hirschfeld, I. Vekhter, A. B. Vorontsov

Experiments on several novel superconducting compounds have observed oscillations of the specific heat when an applied magnetic field is rotated with respect to the crystal axes. The results are commonly interpreted as arising from the nodes of an unconventional order parameter, but the identifications of nodal directions are sometimes controversial. Here we

Alfredo Brega, Leandro Cagliero

In this paper we obtain the LU-decomposition of a noncommutative linear system of equations that, in the rank one case, characterizes the image of the Lepowsky homomorphism $U(\lieg)^{K}\to U(\liek)^{M}\otimes U(\liea)$. This LU-decomposition can be transformed into very simple matrix identities, where the entries of the matrices involved belong to a special

S. Eckel, A. O. Sushkov, S. K. Lamoreaux

We study the magnetic properties of Gadolinium-Yttrium Iron Garnet ($\text{Gd}_{x}\text{Y}_{3-x}\text{Fe}_5\text{0}_{12}$, $x=3,1.8$) ferrite ceramics. The complex initial permeability is measured in the temperature range 2 K to 295 K at frequency of 1 kHz, and in the frequency range 100 Hz to 200 MHz at temperatures 4 K, 77 K, and 295 K. The magnetic viscos

D. Dujmic, P. Fisher, R. Lanza, J. Lopez

The known direction of motion of dark matter particles relative to the Earth may be a key for their unambiguous identification even in the presence of backgrounds. We describe a prototype detector that is able to reconstruct direction vectors of weakly interacting massive particles that may the dominant constituent of the dark matter in our galaxy. The detec

Raimundas Vidunas, Alexander V. Kitaev

Various Schlesinger transformations can be combined with a direct pull-back of a hypergeometric 2x2 system to obtain $RS^2_4$-pullback transformations to isomonodromic 2x2 Fuchsian systems with 4 singularities. The corresponding Painleve VI solutions are algebraic functions, possibly in different orbits under Okamoto transformations. This paper demonstrates

C. Glasman, R. M. Jones

Higher order modes (HOMs) are simulated with finite element and finite difference computer codes for the ILC superconducting cavities. In particular, HOMs in KEK's Ichiro type of cavity and Cornell University's Reentrant design are focused on in this work. The aim, at these universities and laboratories, is to achieve an accelerating gradient in exce

Nir Ailon

The LETOR website contains three information retrieval datasets used as a benchmark for testing machine learning ideas for ranking. Algorithms participating in the challenge are required to assign score values to search results for a collection of queries, and are measured using standard IR ranking measures (NDCG, precision, MAP) that depend only the relativ

I. Shinton, R. M. Jones

The globalised cascaded scattering matrix technique is a well proven, practical method that can be used to simulate large accelerating RF structures in which realistic fabrication errors to be incorporated in an efficient manner without the necessity to re-mesh the entire geometry. The globalised scattering matrix (GMS) technique allows one to obtain the sca

Andrew Ranicki

Given a noncommutative (Cohn) localization $A \to σ^{-1}A$ which is injective and stably flat we obtain a lifting theorem for induced f.g. projective $σ^{-1}A$-module chain complexes and localization exact sequences in algebraic $L$-theory, matching the algebraic $K$-theory localization exact sequence of Neeman and Ranicki.

P. Das, M. R. Koblischka, H. Rosner, Th. Wolf

We performed scanning tunneling spectroscopic experiments on hole-doped NdBa$_2$Cu$_3$O$_{7-δ}$. The d$I$/d$V$ curves obtained at 4.2 K are asymmetric with clear peak-dip and hump structures. Energy derivatives of these curves show peaks at energies beyond the dip features. Highly precise full potential bandstructure calculations confirm a featureless electr

Claudio Carmeli, Teiko Heinosaari, Juha-Pekka Pellonpää, Alessandro Toigo

We study various optimality criteria for quantum observables. Observables are represented as covariant positive operator valued measures and we consider the case when the symmetry group is compact. Phase observables are examined as an example.

V. Khan, R. M. Jones

The CLIC linear collider aims at accelerating multiple bunches of electrons and positrons and colliding them at a centre of mass energy of 3 TeV. These bunches will be accelerated through X-band linacs, operating at an accelerating frequency of 12 GHz. Each beam readily excites wake-fields within the accelerating cavities of each linac. The transverse compon

A. O. Sushkov, S. Eckel, S. K. Lamoreaux

We address a number of issues regarding solid state electron electric dipole moment (EDM) experiments, focusing on gadolinium iron garnet (abbreviated GdIG, chemical formula Gd$_3$Fe$_5$O$_{12}$) as a possible sample material. GdIG maintains its high magnetic susceptibility down to 4.2 K, which enhances the EDM-induced magnetization of a sample placed in an

P. A. Sturrock

Recent coordinated power-spectrum analyses of radiochemical solar neutrino data and the solar irradiance have revealed a highly significant, high-Q common modulation at 11.85 yr-1. Since the stability of this frequency points to an explanation in terms of rotation, this result may be attributable to non-spherically-symmetric nuclear burning in a solar core w

Jaume Llibre, Claudio Pessoa

Let X be a homogeneous polynomial vector field of degree 2 on S^2. We show that if X has at least a non--hyperbolic singularity, then it has no limit cycles. We give necessary and sufficient conditions for determining if a singularity of X on S^2 is a center and we characterize the global phase portrait of X modulo limit cycles. We also study the Hopf bifurc

W. Salah, R. M. Jones

Based on Lienard-Weichert retarded potentials and the potential due to the image of charges on the cathode, a rigorous relativistic description of the beam transport inside the RF-photoinjector is presented. The velocity dependent effects are taken into account. Simulations are presented for parameters of the "ELSA" photo-cathode

Constanze Liaw, Sergei Treil

We consider rank one perturbations $A_α=A+α(\cdot,φ)φ$ of a self-adjoint operator $A$ with cyclic vector $φ\in\mathcal H_{-1}(A)$ on a Hilbert space $\mathcal H$. The spectral representation of the perturbed operator $A_α$ is given by a singular integral operator of special form. Such operators exhibit what we call 'rigidity' and are connected with t

Christoph Kirst, Theo Geisel, Marc Timme

The response of a neuron to synaptic input strongly depends on whether or not it has just emitted a spike. We propose a neuron model that after spike emission exhibits a partial response to residual input charges and study its collective network dynamics analytically. We uncover a novel desynchronization mechanism that causes a sequential desynchronization t

Q. Song, H. Cao, S. T. Ho, G. S. Solomon

We report single-mode lasing in subwavelength GaAs disks under optical pumping. The disks are fabricated by standard photolithography and two steps of wet chemical etching. The simple fabrication method can produce submicron disks with good circularity, smooth boundary and vertical sidewalls. The smallest lasing disks have a diameter of 627 nm and thickness

Robert R. Gibson, Linhua Jiang, W. N. Brandt, Patrick B. Hall

We present a catalog of 5039 broad absorption line (BAL) quasars (QSOs) in the Sloan Digital Sky Survey (SDSS) Data Release 5 (DR5) QSO catalog that have absorption troughs covering a continuous velocity range >= 2000 km/s. We have fit ultraviolet (UV) continua and line emission in each case, enabling us to report common diagnostics of BAL strengths and velo

Zhihang Yi, Il-Min Kim

This paper focuses on analog network coding (ANC) and time division broadcasting (TDBC) which are two major protocols used in bidirectional cooperative networks. Lower bounds of the outage probabilities of those two protocols are derived first. Those lower bounds are extremely tight in the whole signal-to-noise ratio (SNR) range irrespective of the values of

Arnab K. Ray

In this pedagogically motivated work, the process of migration in reflection seismics has been considered from a rigorously mathematical viewpoint. An inclined subsurface reflector with a constant dipping angle has been shown to cause a shift in the normal moveout equation, with the peak of the moveout curve tracing an elliptic locus. Since any subsurface re

Goetz Pfeiffer

The descent algebra of a finite Coxeter group $W$ is a basic algebra, and as such it has a presentation as quiver with relations. In recent work, we have developed a combinatorial framework which allows us to systematically compute such a quiver presentation for a Coxeter group of a given type. In this article, we use that framework to determine quiver prese

L. F. Palhares, E. S. Fraga, C. Villavicencio

We consider two-flavor asymmetric QCD combined with a low-energy effective model inspired by chiral perturbation theory and lattice data to investigate the effects of masses, isospin and baryon number on the pressure and the deconfinement phase transition. Remarkable agreement with lattice results is found for the critical temperature behavior. Further analy

Gerd Grubb

The paper reports on a recent construction of M-functions and Krein resolvent formulas for general closed extensions of an adjoint pair, and their implementation to boundary value problems for second-order strongly elliptic operators on smooth domains. The results are then extended to domains with $C^{1,1}$ Hölder smoothness, by use of a recently developed c

S. Marcello

The PANDA detector is under design to be installed at the HESR storage ring for antiproton of the future FAIR facility in Darmstadt, Germany. Fundamental questions of hadron and nuclear physics interactions of antiprotons with nucleons and nuclei will be pursued using a multipurpose set-up which includes innovative detectors. Here, the FAIR facility and the

Alberto Elduque

Models of all the gradings on the exceptional simple Lie algebras induced by Jordan subgroups of their groups of automorphisms are provided.

Y. Gallais, A. Sacuto, M. Cazayous, P. Cheng

We report plane-polarized Raman scattering spectra of iron oxypnictide superconductor NdFeAsO$_{1-x}$F$_x$ single crystals with varying fluorine $x$ content. The spectra exhibit sharp and symmetrical phonon lines with a weak dependence on fluorine doping $x$. The temperature dependence does not show any phonon anomaly at the superconducting transition. The F

Yago Antolin, Warren Dicks, Peter A. Linnell

Recently Dicks-Linnell determined the $L^2$-Betti numbers of the orientable surface-plus-one-relation groups, and their arguments involved some results that were obtained topologically by Hempel and Howie. Using algebraic arguments, we now extend all these results of Hempel and Howie to a larger class of two-relator groups, and we then apply the extended res

A. Filinov, P. Ludwig, M. Bonitz, Yu. E. Lozovik

Using an adiabatic approximation we derive an effective interaction potentially for spatially indirect excitons. Using this potential and path integral Monte Carlo simulations we study exciton crystllization and the quantum melting phase transition in a macroscopic system of 2D excitons. Furthermore, the superfluid fraction is calculated as a function of den

J. Cernicharo, M. Guélin, M. Agúndez, M. C. McCarthy

We report the detection in the envelope of the C-rich star IRC +10216 of four series of lines with harmonically related frequencies: B1389, B1390, B1394 and B1401. The four series must arise from linear molecules with mass and size close to those of C6H and C5N. Three of the series have half-integer rotational quantum numbers; we assign them to the 2Delta an

Hilarion L. M. Faliharimalala, Jiang Zeng

Euler's difference table associated to the sequence $\{n!\}$ leads naturally to the counting formula for the derangements. In this paper we study Euler's difference table associated to the sequence $\{\ell^n n!\}$ and the generalized derangement problem. For the coefficients appearing in the later table we will give the combinatorial interpretations

Alberto D. Bolatto, Adam K. Leroy, Erik Rosolowsky, Fabian Walter

Giant molecular clouds (GMCs) are the major reservoirs of molecular gas in galaxies, and the starting point for star formation. As such, their properties play a key role in setting the initial conditions for the formation of stars. We present a comprehensive combined inteferometric/single-dish study of the resolved GMC properties in a number of extragalactic

Gustavo E. Romero

Star-forming regions have been tentatively associated with gamma-ray sources since the early days of the COS B satellite. After the Compton Gamma-Ray Observatory, the statistical evidence for such an association has became overwhelming. Recent results from Cherenkov telescopes indicate that some high-energy sources are produced in regions of active star form

I. A. Bonnell, W. K. M. Rice

The presence of young massive stars orbiting on eccentric rings within a few tenths of a parsec of the supermassive black hole in the Galactic centre is challenging for theories of star formation. The high tidal shear from the black hole should tear apart the molecular clouds that form stars elsewhere in the Galaxy, while transporting the stars to the Galact

Katie Mussack, Douglas Gough

The revision of the photospheric abundances proferred by Asplund et al has rendered opacity theory inconsistent with the seismologically determined opacity through the Sun. This highlights the need for a direct seismological measurement of solar abundances. Here we describe the technique used to measure abundances with seismology, examine our ability to dete

Andreas Cap, Vojtech Zadnik

Contact projective structures have been profoundly studied by D.J.F. Fox. He associated to a contact projective structure a canonical projective structure on the same manifold. We interpret Fox' construction in terms of the equivalent parabolic (Cartan) geometries, showing that it is an analog of Fefferman's construction of a conformal structure asso

Gul Rahman, Víctor M. García-Suárez, Soon Cheol Hong

We study the magnetic and electronic properties of defects in SnO$_{2}$ using pseudopotential and all electron methods. Our calculations show that bulk SnO$_{2}$ is non-magnetic, but it shows magnetism with a magnetic moment around 4.00 $μ_{B}$ due to Sn vacancy (V$_\mathrm{Sn}$). The magnetic moment comes mainly from O atoms surrounding V$_\mathrm{Sn}$ and

Y. Schroder

In this talk, I present the status of attempts to analyze the behavior of the so-called spatial 't Hooft loop, which can be taken as an order parameter for the deconfinement phase transition in pure SU(N) gauge theory. While lattice data show a strikingly universal scaling of extracted k-string tensions for various values of k and N, the analytic approac

Martin Hasenbusch

We simulate lattice models in the three-dimensional XY universality class in the low and the high temperature phase. This allows us to compute a number of universal amplitude ratios with unprecedented precision: R_Υ=0.411(2), R_B=2.83(1), R_ξ^+=0.3562(10) and R_ξ^-=0.850(5). These results can be compared with those obtained from other theoretical methods, su

Mauricio Cataldo, Pedro Labrana, Sergio del Campo, Juan Crisostomo

In this paper we study the possibility of sustaining an evolving wormhole via exotic matter made out of phantom energy. We show that this exotic source can support the existence of evolving wormhole spacetimes. Explicitly, a family of evolving Lorentzian wormholes conformally related to another family of zero-tidal force static wormhole geometries is found i

S. Bagnulo, I. Belskaya, K. Muinonen, G. P. Tozzi

Trans-Neptunian objects (TNOs) contain the most primitive and thermally least-processed materials from the early accretional phase of the solar system. They allow us to study interrelations between various classes of small bodies, their origin and evolution. Using FORS1 of the ESO VLT, we have obtained linear-polarization measurements in the Bessell R filter

A. Bessa, C. A. A. de Carvalho, E. S. Fraga

Several relevant aspects of quantum-field processes can be well described by semiclassical methods. In particular, the knowledge of non-trivial classical solutions of the field equations, and the thermal and quantum fluctuations around them, provide non-perturbative information about the theory. In this work, we discuss the calculation of the one-loop effect

V. S. Filinov, M. Bonitz, H. Fehske, P. R. Levashov

We investigate structures of 2D quantum electron-hole (e-h) plasmas by the direct path integral Monte Carlo method (PIMC) in a wide range of temperature, density and hole-to-electron mass ratio. Our simulation includes a region of appearance and decay of the bound states (excitons and biexcitons), the Mott transition from the neutral e-h plasma to metallic-l

Paolo Soffitta, Ronaldo Bellazzini, Gianpiero Tagliaferri, Enrico Costa

The development of micropixel gas detectors, capable to image tracks produced in a gas by photoelectrons, makes possible to perform polarimetry of X-ray celestial sources in the focus of grazing incidence X-ray telescopes. HXMT is a mission by the Chinese Space Agency aimed to survey the Hard X-ray Sky with Phoswich detectors, by exploitation of the direct d

Yan-Xiao Gong, Xu-Bo Zou, Yun-Feng Huang, Guang-Can Guo

We propose a simple scheme for expanding a polarization-entangled W state. By mixing a single photon and one of the photons in an n-photon W state at a polarization-dependent beam splitter (PDBS), we can obtain an (n+1)-photon W state after post-selection. Our scheme also opens the door for generating n-photon W states using single photons and linear optics.

Christopher C. Stark, Marc J. Kuchner

Directly imaging extrasolar terrestrial planets necessarily means contending with the astrophysical noise of exozodiacal dust and the resonant structures created by these planets in exozodiacal clouds. Using a custom tailored hybrid symplectic integrator we have constructed 120 models of resonant structures created by exo-Earths and super-Earths on circular

Johannes Frantti, Yukari Fujioka, Risto M. Nieminen

The origin of the very large piezoelectric response observed in the vicinity of the morphotropic phase boundary (MPB) in perovskite lead zirconate titanate and related systems has been under intensive studies. Polarization rotation ideas are frequently invoked to explain the piezoelectric properties. It was recently reported that lead titanate undergoes a ph

Enrico Costa, Ronaldo Bellazzini, Jean Bregeon, Alessandro Brez

The XEUS mission incorporates two satellites: the Mirror Spacecraft with 5 m2 of collecting area at 1 keV and 2 m2 at 7 keV, and an imaging resolution of 5" HEW and the Payload Spacecraft which carries the focal plane instrumentation. XEUS was submitted to ESA Cosmic Vision and was selected for an advanced study as a large mission. The baseline design in

Juan E. Peralta, Veronica Barone

We propose a method for the evaluation of magnetic exchange couplings based on noncollinear spin-density functional calculations. The method employs the second derivative of the total Kohn-Sham energy of a single reference state, in contrast to approximations based on Kohn-Sham total energy differences. The advantage of our approach is twofold: It provides a

Y. Ao, A. Weiss, D. Downes, F. Walter

Using the IRAM 30m telescope and the Plateau de Bure interferometer we have detected the \ctwo and the CO 3$-$2, 4$-$3, 6$-$5, 7$-$6 transitions as well as the dust continuum at 3 and 1.2 mm towards the distant luminous infrared galaxy IRAS F10214+4724 at $z=2.286$. The \ctwo line is detected for the first time towards this source and IRAS F10214+4724 now be

L. Sunil Chandran, Anita Das, Naveen Sivadasan

{\it A unit cube in $k$-dimension (or a $k$-cube) is defined as the cartesian product $R_1 \times R_2 \times ... \times R_k$, where each $R_i$ is a closed interval on the real line of the form $[a_i, a_i+1]$. The {\it cubicity} of $G$, denoted as $cub(G)$, is the minimum $k$ such that $G$ is the intersection graph of a collection of $k$-cubes. Many NP-comple

Fabio Muleri, Paolo Soffitta, Ronaldo Bellazzini, Alessandro Brez

The Gas Pixel Detector (GPD) is a new generation device which, thanks to its 50 um pixels, is capable of imaging the photoelectrons tracks produced by photoelectric absorption in a gas. Since the direction of emission of the photoelectrons is strongly correlated with the direction of polarization of the absorbed photons, this device has been proposed as a po

D. G. Eshchenko, V. G. Storchak, S. P. Cottrell, E. Morenzoni

The charge dynamics of hydrogen-like centers formed by the implantation of energetic (4 MeV) muons in semi-insulating GaAs have been studied by muon spin resonance in electric fields. The results point to the significant role of deep hole traps in the compensation mechanism of GaAs. Electric-field-enhanced neutralization of deep electron and hole traps by mu

Gonzalo García-Reyes, Guillermo A. González

A detailed study is presented of the counterrotating model (CRM) for electrovacuum stationary axially symmetric relativistic thin disks of infinite extension without radial stress, in the case when the eigenvalues of the energy-momentum tensor of the disk are real quantities, so that there is not heat flow. We find a general constraint over the counterrotati

Andrei M. Beloborodov

Hyper-accretion disks are short-lived, powerful sources of neutrinos and magnetized jets. Such disks are plausible sources of gamma-ray bursts. This review describes the disk structure, the neutrino conversion to electron-positron plasma around the disk, and the post-burst evolution.

HESS Collaboration, F. Aharonian

The shell-type supernova remnant (SNR) RCW 86, possibly associated with the historical supernova SN 185, with its relatively large size (about 40' in diameter) and the presence of non-thermal X-rays is a promising target for gamma-ray observations. The high sensitivity, good angular resolution of a few arc minutes and the large field of view of the High

Matyas Barczy, Gyula Pap

We study asymptotic behavior of maximum likelihood estimator for a time inhomogeneous diffusion process given by a SDE $dX_t=αb(t)X_t dt + σ(t) dB_t$, $t\in[0,T)$, with a parameter $α\in R$, where $T\in(0,\infty]$ and $(B_t)_{t\in[0,T)}$ is a standard Wiener process. We formulate sufficient conditions under which the MLE of $α$ normalized by Fisher informati

A. J. de Jong, Robert Friedman

Let $B$ be a curve defined over an algebraically closed field $k$ and let $X\to B$ be an elliptic surface with base curve $B$. We investigate the geometry of everywhere locally trivial principal homogeneous spaces for $X$, i.e. elements of the Tate-Shafarevich group. If $Y$ is such a principal homogeneous space of order $n$, we find strong restrictions on th

Francesco Sannino, Roman Zwicky

We propose a generic framework in which the Higgs and the unparticle are both composite. The underlying theories are four dimensional, asymptotically free, nonsupersymmetric gauge theories with fermionic matter. We sketch a possible uni- fication of these two sectors at a much higher scale resembling extended technicolor models. By construction our extension

Fabio Muleri, Paolo Soffitta, Ronaldo Bellazzini, Alessandro Brez

We devised and built a versatile facility for the calibration of the next generation X-ray polarimeters with unpolarized and polarized radiation. The former is produced at 5.9 keV by means of a Fe55 radioactive source or by X-ray tubes, while the latter is obtained by Bragg diffraction at nearly 45 degrees. Crystals tuned with the emission lines of X-ray tub

Andrew Burgess, Jerome Bouvier, Estelle Moraux

IC 348 is a young (t$\sim$3Myr) and nearby (d$\sim$340pc) star forming region in the Perseus molecular cloud. We performed a deep imaging survey using the MEGACAM (z-band) and WIRCAM (JHK and narrowband CH${_4}$ on/off) wide-field cameras on the Canada-France-Hawaii Telescope. From the analysis of the narrowband CH${_4}$ on/off deep images, we report 4 T-dwa

Emmanuel Breuillard, Peter Friz, Martin Huesmann

Donsker's invariance principle is shown to hold for random walks in rough path topology. As application, we obtain Donsker-type weak limit theorems for stochastic integrals and differential equations.

F. Huang, A. Sibirtsev, S. Krewald, C. Hanhart

The amplitudes for the pion-nucleon charge exchange reaction of the Karlsruhe-Helsinki and the George-Washington-University partial wave analyses are compared with those of a Regge-cut model with the aim to explore the possibility to provide high energy constraints for theoretical baryon resonance analyses in the energy region above 2 GeV.

T. Mertens, I. Jaegle, P. Muehlich, J. C. S. Bacelar

Photoproduction of $η$ mesons off $^{12}$C, $^{40}$Ca, $^{93}$Nb, and $^{nat}$Pb nuclei has been measured with a tagged photon beam with energies between 0.6 and 2.2 GeV. The experiment was performed at the Bonn ELSA accelerator with the combined setup of the Crystal Barrel and TAPS calorimeters. It aimed at the in-medium properties of the S$_{11}$(1535) nuc

Berin Belma Sirvanli

Double-lepton polarization asymmetries for the exclusive decay B->K_1 l^+ l^- in the Universal Extra Dimension (UED) Model is studied. It is obtained that double-lepton polarization asymmetries are very sensitive to the UED model parameters. Experimental measurements of double lepton polarizations can give valuable information on the physics beyond the Stand

Haibo Ma, Ulrich Schollwoeck

Dynamical simulations of polaron transport in conjugated polymers in the presence of an external time-dependent electric field have been performed within a combined extended Hubbard model (EHM) and Su-Schrieffer-Heeger (SSH) model. Nearly all relevant electron-phonon and electron-electron interactions are fully taken into account by solving the time-dependen

Charles Bonatto, Eduardo Bica

(Abridged) - The combination of several mass-decreasing processes may critically affect the structure of open clusters (OCs), to the point that most dissolve into the field in a time-scale shorter than $\approx1$ Gyr. In this paper we focus on 4 candidate old star clusters, namely, LK 1, LK 10, FSR 1521, and FSR 1555. To analyse the target clusters we constr

Martin Mathieu

We discuss several open problems on spectrally bounded operators, some new, some old, adding in a few new insights.

Soham Biswas, Anjan Kumar Chandra, Parongama Sen

We investigate the dynamics of a two dimensional axial next nearest neighbour Ising (ANNNI) model following a quench to zero temperature. The Hamiltonian is given by $H = -J_0\sum_{i,j=1}^L S_{i,j}S_{i+1,j} - J_1\sum_{i,j=1} [S_{i,j} S_{i,j+1} -κS_{i,j} S_{i,j+2}]$. For $κ<1$, the system does not reach the equilibrium ground state but slowly evolves to a met

A. V. Yulin, O. A. Egorov, F. Lederer, D. V. Skryabin

We report the existence, symmetry breaking and other instabilities of dark polariton-solitons in semiconductor microcavities operating in the strong coupling regime. These half-light half-matter solitons are potential candidates for applications in all-optical signal processing. Their excitation time and required pump powers are a few orders of magnitude les

P. Stoklosa, W. Placzek, M. Skrzypek

We present two Monte Carlo algorithms of the Markovian type which solve the modified QCD evolution equations at the NLO level. The modifications with respect to the standard DGLAP evolution concern the argument of the strong coupling constant alpha_S. We analyze the z - dependent argument and then the k_T - dependent one. The evolution time variable is ident

Mary E. K. Williams, Ken C. Freeman, Amina Helmi, the RAVE collaboration

The Arcturus moving group is a well-populated example of phase space substructure within the thick disk of our Galaxy. Traditionally regarded as the remains of a dissolved open cluster, it has recently been suggested to be a remnant of a satellite accreted by our Galaxy. To investigate the origin of the group we undertook a high-resolution spectroscopic abun

Alexei Yu. Smirnov

Our present knowledge of neutrinos can be summarized in terms of the &#34;standard neutrino scenario&#34;. Phenomenology of this scenario as well as attempts to uncover physics behind neutrino mass and mixing are described. Goals of future studies include complete reconstruction of the neutrino mass and flavor spectrum, further test of the standard scenario

Flavien Paccot, Philippe Lemoine, Nicolas Andreff, Damien Chablat

In this paper, a novel approach for parallel kinematic machine control relying on a fast exteroceptive measure is implemented and validated on the Orthoglide robot. This approach begins with rewriting the robot models as a function of the only end-effector pose. It is shown that such an operation reduces the model complexity. Then, this approach uses a class

Katarzyna Szymanska

One of the goals of hypernuclear physics is to study the properties of baryon-baryon interaction including the strangeness contribution. Double hypernuclei can provide information about the $ΛΛ$ interaction in addition to the hyperon-hyperon and hyperon-nucleus one. A new technique for producing double hypernuclei using antiprotons is foreseen in the PANDA e

F. Paletou

In his famous monographs, Einar Tandberg-Hanssen writes that &#34;the single, physically most important parameter to study in prominences may be the magnetic field. Shapes, motions, and in fact the very existence of prominences depend on the nature of the magnetic field threading the prominence plasma&#34;. Hereafter we sumarize recent contributions and adva

Per Groeningsson, Claes Fransson, Bruno Leibundgut, Peter Lundqvist

We present seven epochs between October 1999 and November 2007 of high resolution VLT/UVES echelle spectra of the ejecta-ring collision of SN 1987A. The fluxes of most of the narrow lines from the unshocked gas decreased by a factor of 2-3 during this period, consistent with the decay from the initial ionization by the shock break-out. However, [O III] in pa

Sergio Caracciolo, Enrico Rinaldi, Andrea Sportiello

We discuss an algorithm for the exact sampling of vectors v in [0,1]^N satisfying a set of pairwise difference inequalities. Applications include the exact sampling of skew Young Tableaux, of configurations in the Bead Model, and of corrugated surfaces on a graph, that is random landscapes in which at each vertex corresponds a local maximum or minimum. As an

Fernando Casas, Ander Murua

We provide a new algorithm for generating the Baker--Campbell--Hausdorff (BCH) series $Z = \log(\e^X \e^Y)$ in an arbitrary generalized Hall basis of the free Lie algebra $\mathcal{L}(X,Y)$ generated by $X$ and $Y$. It is based on the close relationship of $\mathcal{L}(X,Y)$ with a Lie algebraic structure of labeled rooted trees. With this algorithm, the com

Yonggang Yang, Oliver Kühn

We present a straightforward method for obtaining exact classical and quantum molecular Hamiltonians in terms of arbitrary coordinates. As compared to other approaches the resulting expression are rather compact, the physical meaning of each quantity is quite transparent, and in some cases the calculation effort will be greatly reduced. We also investigate s

Viorica Sofronie-Stokkermans

In this paper we study possibilities of efficient reasoning in combinations of theories over possibly non-disjoint signatures. We first present a class of theory extensions (called local extensions) in which hierarchical reasoning is possible, and give several examples from computer science and mathematics in which such extensions occur in a natural way. We

M. Gungormez, H. R. Karadayi

In a previous work, we have given an explicit method to obtain irreducible characters of finite Lie algebras without referring to Weyl character formula. Irreducible characters of $G_2$ Lie algebra has been given as an example. The work is now extended to somewhat more complicated case of $F_4$ Lie algebra, in the same manner.

Denes Sexty

Stochastic quantisation is applied to the problem of calculating real-time evolution on a Minkowskian space-time lattice. We employ optimized updating using reweighting, or gauge fixing, respectively. These procedures do not affect the underlying theory, but strongly improve the stability properties of the stochastic dynamics.

B. W. Holwerda, W. C. Keel, B. Williams, J. J. Dalcanton

We present an analysis of an occulting galaxy pair, serendipitously discovered in ACS Nearby Galaxy Survey Treasury (ANGST) observations of NGC 253 taken with Hubble Space Telescope&#39;s Advanced Camera for Survey in F475W, F606W$ and F814W (SDSS-g, broad V and I). The foreground disk system (at z < 0.06) shows a dusty disk much more extended than the starl

P. Capel, D. Baye, Y. Suzuki

The eikonal description of breakup reactions diverges because of the Coulomb interaction between the projectile and the target. This divergence is due to the adiabatic, or sudden, approximation usually made, which is incompatible with the infinite range of the Coulomb interaction. A correction for this divergence is analysed by comparison with the Dynamical

Simen Kvaal

We describe OpenFCI, an open source implementation of the full configuration-interaction method (FCI) for two-dimensional quantum dots with optional use of effective renormalized interactions. The code is written in C++ and is available under the Gnu General Public License. The code and core libraries are well documented and structured in a way such that cus

Linda Mthembu, Tshilidzi Marwala, Michael I. Friswell, Sondipon Adhikari

This paper considers the problem of model selection within the context of finite element model updating. Given that a number of FEM updating models, with different updating parameters, can be designed, this paper proposes using the Bayesian evidence statistic to assess the probability of each updating model. This makes it possible then to evaluate the need f

A. D. Gazazyan, E. A. Gazazyan, A. G. Margaryan

The possibility of storage of quantum information with photons is studied in the case of resonant transitions via many close lying exciton levels in a solid with impurity Lambda-atoms. The upper levels of the impurity atom form resonant Fano states, similar to the autoionization atomic states, due to the configuration interaction with the continuum of the ex

Alexander A. Borisenko

Life and the mathematical legacy of the great mathematician A.V. Pogorelov.

Jerome Bouvier, Tim Kendall, Gwendolyn Meeus

We present the results of a search for brown dwarfs (BDs) and very low mass (VLM) stars in the 625 Myr-old, metal-rich ([Fe/H]=0.14) Hyades cluster. We performed a deep (I=23, z=22.5) photometric survey over 16 deg$^2$ around the cluster center. We report the discovery of the first 2 BDs in the Hyades cluster, with a spectral type T1 and T2, respectively. Th

Naceur-Eddine Khélifa

We discuss the application of stress-induced changes in the crystal of a monolithic Nd:YAG laser as a possibility for microforce measurement. In fact, application of an unknown force on the resonator-amplifier-crystal can lead to a several gigahertz change, depending on the force intensity, of the laser frequency. In addition, the changes rates of the two or

Han Siong Ch&#39;ng

Accelerating cosmologies in extra dimensional spaces have been studied. These extra dimensional spaces are products of many spaces. The physical behaviors of accelerating cosmologies are investigated from Einstein&#39;s field equation in higher dimensional Friedmann-Robertson-Walker (FRW) universe and superstring/M theory points of view. It is found that if

Crystal Hoyt, Vera Serganova

A contragredient Lie superalgebra is a superalgebra defined by a Cartan matrix. A contragredient Lie superalgebra has finite-growth if the dimensions of the graded components (in the natural grading) depend polynomially on the degree. In this paper we classify finite-growth contragredient Lie superalgebras. Previously, such a classification was known only fo

A. Hasanov

In this paper, using similar symbolical method of Burchnall and Chaundy formulas of expansion for the generalized hypergeometric function were constructed. By means of the found formulas of expansion the formulas of an analytic continuation for hypergeometric function of Clausen is defined. The obtained formulas of an analytic continuation express known hype

Jan Soubusta, Lucie Bartuskova, Antonin Cernoch, Miloslav Dusek

We report on two optical realizations of the $1 \to 2$ asymmetric phase-covariant cloning machines for polarization states of single photons. The experimental setups combine two-photon interference and tunable polarization filtering that enables us to control the asymmetry of the cloners. The first scheme involves a special unbalanced bulk beam splitter exhi

Marco Caminati

A precise tie between a univariate spline&#39;s knots and its zeros abundance and dissemination is formulated. As an application, a conjecture formulated by De Concini and Procesi is shown to be true in the special univariate, unimodular case. As a supplement, the same conjecture is shown, through computing a counterexample, to be false when unimodularity hy

K Balzer, M Bonitz

A nonequilibrium Green&#39;s functions (NEGF) approach for spatially inhomogeneous, strongly correlated artificial atoms is presented and applied to compute the time-dependent properties while starting from a (correlated) initial few-electron state at finite temperatures. In the regime of moderate to strong coupling, we consider the Kohn mode of a three-elec

A. Hasanov

By making use of some techniques based upon certain inverse new pairs of symbolic operators, the author investigate several decomposition formulas associated with Lauricella&#39;s hypergeometric functions $F_A^{(r)}, F_B^{(r)}, F_C^{(r)}$ and $F_D^{(r)}$ in $r$ variables. In the three-variable case some of these operational representations are constructed an

Nicola Ambrosetti, James Charbonneau, Silke Weinfurtner

This is a paper compiled by students of the 2008 Summer School on Particles, Fields, and Strings held at the University of British Columbia on lectures given by Veronika Hubeny as understood and interpreted by the authors. We start with an introduction to the AdS/CFT duality. More specifically, we discuss the correspondence between relativistic, conformal hy