June 2007 arXiv papers — page 38

R. Mecheri, E. Marsch

Spectroscopic observations and theoretical models suggest resonant wave-particle interactions, involving high-frequency ion-cyclotron waves, as the principal mechanism for heating and accelerating ions in the open coronal holes. However, the mechanism responsible for the generation of the ion-cyclotron waves remains unclear. One possible scenario is that ion

Junhao Shen

In the paper, we discuss orthogonal polynomials in free probability theory. Especially, we prove an analogue of of Szego's limit theorem in free probability theory.

Sandrine Peche, Alexander Soshnikov

We show that the spectral radius of an $N\times N$ random symmetric matrix with i.i.d. bounded centered but non-symmetrically distributed entries is bounded from below by $ 2 \*σ- o(N^{-6/11+ε}), $ where $σ^2 $ is the variance of the matrix entries and $ε$ is an arbitrary small positive number. Combining with our previous result from [7], this proves that fo

B. E. Zhilyaev

Using the BATSE survey data I find that quite small fraction of GRBs numbering 37 sources seems to emit the radiation similar to thermal bremsstrahlung in the range 20 to 300 keV. I suggest that these bursts may perhaps occur from collision of stars with primordial black holes (PBH). These objects are relic of a hot matter in the early Universe. PBH in the v

B. Y. Welsh, J. Edelstein, E. Korpela

We present far ultraviolet (FUV: 912 - 1750AA) spectral imaging observations recorded with the SPEAR satellite of the interstellar OVI (1032AA), CIV (1550AA), SiIV (1394AA), SiII* (1533AA) and AlII (1671AA) emission lines originating in a 60 x 30 degree rectangular region lying close to the North Galactic Pole. These data represent the first large area, mode

Urs Hackstein

We define functorial isomorphisms of parallel transport along étale paths for a class of principal $G$-bundles on a $p$-adic curve. Here $G$ is a connected reductive algebraic group of finite presentation and the considered principal bundles are just those with potentially strongly semistable reduction of degree zero. The constructed isomorphisms yield conti

M. Stepanova, E. E. Antonova, J. M. Bosqued

Plasma pressure distribution in the inner magnetosphere is one of the key parameters for understanding the main magnetospheric processes including geomagnetic storms and substorms. However, the pressure profiles obtained from in-situ particle measurements by the high-altitude satellites do not allow tracking the pressure variations related to the storms and

G. Menezes, N. F. Svaiter

We consider the stochastic quantization method for scalar fields defined in a curved manifold and also in a flat space-time with event horizon. The two-point function associated to a massive self-interacting scalar field is evaluated, up to the first order level in the coupling constant, for the case of an Einstein and also a Rindler Euclidean metric, respec

D. Prezzi, D. Varsano, A. Ruini, A. Marini

We investigate from first principles the optoelectronic properties of nanometer-sized armchair graphene nanoribbons (GNRs). We show that many-body effects are essential to correctly describe both energy gaps and optical response. As a signature of the confined geometry, we observe strongly bound excitons dominating the optical spectra, with a clear family de

M. Korkusinski, P. Hawrylak, A. Babinski, M. Potemski

We present a theory and experiment demonstrating optical readout of charge and spin in a single InAs/GaAs self-assembled quantum dot. By applying a magnetic field we create the filling factor 2 quantum Hall singlet phase of the charged exciton. Increasing or decreasing the magnetic field leads to electronic spin-flip transitions and increasing spin polarizat

A. El Soufi, E. M. Harrell, S. Ilias

We establish inequalities for the eigenvalues of Schrödinger operators on compact submanifolds (possibly with nonempty boundary) of Euclidean spaces, of spheres, and of real, complex and quaternionic projective spaces, which are related to inequalities for the Laplacian on Euclidean domains due to Payne, Pólya, and Weinberger and to Yang, but which depend in

Irene Puerto-Gimenez, Marek Korkusinski, Pawel Hawrylak

We present a computational LCHO-CI approach allowing for the simulation of exchange interactions in gated lateral quantum dot networks. The approach is based on single-particle states calculated using a linear combination of harmonic orbitals (LCHO) of each of the dots, and a configuration interaction (CI) approach to the interacting electron problem. The LC

Faina Berezovskaya, Artem Novozhilov, Georgy Karev

An analysis of traveling wave solutions of partial differential equation (PDE) systems with cross-diffusion is presented. The systems under study fall in a general class of the classical Keller-Segel models to describe chemotaxis. The analysis is conducted using the theory of the phase plane analysis of the corresponding wave systems without a priory restric

E. Momjian, C. L. Carilli, D. A. Riechers, F. Walter

We present sensitive phase-referenced VLBI results on the radio continuum emission from the $z=4.4$ QSO BRI 1335--0417. The observations were carried out at 1.4 GHz using the High Sensitivity Array (HSA). Our sensitive VLBI image at $189 \times 113$ mas ($1.25 \times 0.75$ kpc) resolution shows continuum emission in BRI 1335--0417 with a total flux density o

S. S. Masood, S. Nasri, J. Schechter, M. A. Tórtola

The exact relativistic form for the beta decay endpoint spectrum is derived and presented in a simple factorized form. We show that our exact formula can be well approximated to yield the endpoint form used in the fit method of the KATRIN collaboration. We also discuss the three neutrino case and how information from neutrino oscillation experiments may be u

Leonid Chuzhoy, Zheng Zheng

During the epoch of reionization the 21cm signal is sensitive to the scattering rate of the ultraviolet photons, redshifting across the Lyman_alpha resonance. Here we calculate the photon scattering rate profile for a single ultraviolet source. After taking into account previously neglected natural broadening of the resonance line, we find that photons appro

Geraldo A. Barbosa

Coincidence-structures in the transverse plane of Type-II spontaneous parametric down-conversion carrying orbital angular momentum are obtained. Azimuthal symmetry breaking around the pump beam direction reveals itself on these quantum images. Analytical expressions for the amplitude probability of the down conversion process are shown including the nonlinea

Katarina Kovač, Rachel S. Somerville, James E. Rhoads, Sangeeta Malhotra

We present the clustering properties of 151 Lyman alpha emitting galaxies at z ~ 4.5 selected from the Large Area Lyman Alpha (LALA) survey. Our catalog covers an area of 36' x 36' observed with five narrowband filters. We assume that the angular correlation function w(theta) is well represented by a power law A_w = Theta^(-beta) with slope beta = 0.

Mauro R. Cosentino

We present preliminary results of Upsilon production in p+p collisions at sqrt(s)=200 GeV at central rapidity. This measurement was performed at the STAR experiment through the Upsilon->e^+e^- decay channel. In this manuscript we describe the experimental details, from the development of a specially designed trigger setup to the analysis methods used to disc

Jeffrey L. Hopkins, Robert E. Stencel

Since first observed in the early 1980s, the Hopkins Phoenix Observatory continues its UBV band observations of the long period (27.1 years) eclipsing binary star system epsilon Aurigae. The UBV observations routinely produce standard deviations or data spread better than 0.01 magnitudes many times approaching 0.001 magnitudes. A new infrared photometer has

Brian Batell, Tony Gherghetta

We compute the precise elementary/composite field content of mass eigenstates in holographic duals of warped models in a slice of AdS_5. This is accomplished by decomposing the bulk fields not in the usual Kaluza-Klein basis, but rather into a holographic basis of 4D fields, corresponding to purely elementary source or CFT composite fields. Generically, this

Fred B. Holt

We study the gaps between consecutive prime numbers directly through Eratosthenes sieve. Using elementary methods, we identify a recursive relation for these gaps and for specific sequences of consecutive gaps, known as constellations. Using this recursion we can estimate the numbers of a gap or of a constellation that occur between a prime and its square. T

N. Mhlahlo, D. A. H. Buckley, V. Dhillon, S. Potter

We present optical spectroscopy of EX Hya during its 1991 outburst. This outburst is characterised by strong irradiation of the front face of the secondary star by the white dwarf, an overflowing stream which is seen strongly in HeII and by a dip in the light curves, which extends from 0.1-0.6 in the binary and spin phases. Strong irradiation of the accretio

K. Doubrovinski, M. Herrmann

We investigate two-dimensional neural fields as a model of the dynamics of macroscopic activations in a cortex-like neural system. While the one-dimensional case has been treated comprehensively by Amari 30 years ago, two-dimensional neural fields are much less understood. We derive conditions for the stability for the main classes of localized solutions of

R. MacKenzie, A. Morin-Duchesne, H. Paquette, J. Pinel

We analyze the validity of the adiabatic approximation, and in particular the reliability of what has been called the "standard criterion" for validity of this approximation. Recently, this criterion has been found to be insufficient. We will argue that the criterion is sufficient only when it agrees with the intuitive notion of slowness of evolution

Marcos Jardim, Rafael F. Leao

We give a survey of results relating the restricted holonomy of a Riemannian spin manifold with lower bounds on the spectrum of its Dirac operator, giving a new proof of a result originally due to Kirchberg.

Alexander A. Moiseev, Jonathan F. Ormes, Igor V. Moskalenko

We present here the capabilities of the GLAST Large Area Telescope to detect cosmic ray high-energy (HE) electrons in the energy range from 10 GeV to 1 TeV. We also discuss the science topics that can be investigated with HE electron data and quantify the results with LAT instrument simulations. The science topics include CR propagation, calibration of the I

E. Ostrovsky, Y. Zelikov

Motivated by finance and technical applications, the objective of this paper is to consider adaptive estimation of regression and density distribution based on Fourier-Legendre expansion, and construction of confidence intervals - also adaptive. The estimators are asymptotically optimal and adaptive in the sense that they can adapt to unknown smoothness.

Shlomo Dado, Arnon Dar, Alvaro De Rujula

Recent data gathered and triggered by the SWIFT satellite have greatly improved our knowledge of long-duration gamma ray bursts (GRBs) and X-ray flashes (XRFs). This is particularly the case for the X-ray data at all times. We show that the entire X-ray observations are in excellent agreement with the predictions of the `cannonball' model of GRBs and XRF

J. M. Paredes, M. Ribo, V. Bosch-Ramon, J. R. West

We present a 50 ks observation of the gamma-ray binary LSI+61303 carried out with the ACIS-I array aboard the Chandra X-ray Observatory. This is the highest resolution X-ray observation of the source conducted so far. Possible evidence of an extended structure at a distance between 5 and 12 arcsec towards the North of LSI+61303 have been found at a significa

Nassif Ghoussoub, Abbas Moameni

Selfdual variational calculus is further refined and used to address questions of existence of local and global solutions for various parabolic semi-linear equations, Hamiltonian systems of PDEs, as well as certain nonlinear Schrodinger evolutions. This allows for the resolution of such equations under general time boundary conditions which include the more

Daruo Xie, Matthew Pysher, Jietai Jing, Olivier Pfister

An intrinsically stable type-I optical parametric oscillator was built with a periodically poled KTiOPO4 (PPKTP) crystal to generate a stable bright, continuous-wave, broadband phase-squeezed beam. A 3.2 dB sensitivity enhancement of optical interferometry was demonstrated on weak electrooptic modulation signals within a 20 MHz squeezing bandwidth. This also

Nicolas Saintier

We compute the shape derivative of the first eigenvalue of the 1-Laplacian. As an application, we find that a ball is critical among all volume-preserving deformations.

Nadav Yoran, Anthony J. Short

We show that a classical algorithm efficiently simulating the modular exponentiation circuit, for certain product state input and with measurements in a general product state basis at the output, can efficiently simulate Shor's factoring algorithm. This is done by using the notion of the semi-classical Fourier transform due to Griffith and Niu, and furth

Nachi Gupta, Raphael Hauser, Neil F. Johnson

We discuss a method for predicting financial movements and finding pockets of predictability in the price-series, which is built around inferring the heterogeneity of trading strategies in a multi-agent trader population. This work explores extensions to our previous framework (arXiv:physics/0506134). Here we allow for more intelligent agents possessing a ri

Edward Aboufadel, Timothy Armstrong, Elizabeth Smietana

A position coding pattern is an array of symbols in which subarrays of a certain fixed size appear at most once. So, each subarray uniquely identifies a location in the larger array, which means there is a bijection of some sort from this set of subarrays to a set of coordinates. The key to Fly Pentop Computer paper and other examples of position codes is a

J. A. Ponciano, N. N. Scoccola

We analyze the existence of localized finite energy topological excitations on top of the perturbative pion vacuum within the Skyrme model at finite isospin chemical potential and finite pion mass. We show that there is a critical isospin chemical potential $μ_I^c$ above which such solutions cease to exist. We find that $μ_I^c$ is closely related to the valu

Massimo Ricotti

This paper presents a study of quasi-steady spherical accretion in the early Universe, before the formation of the first stars and galaxies. The main motivation is to derive the basic formulas that will be used in a companion paper to calculate the accretion luminosity of primordial black holes and their effect on the cosmic ionization history. The following

E. Rozbicki, P. Machnikowski

We derive a quantum-kinetic description of phonon-assisted F{ö}rster transfer between two coupled quantum dots (a quantum dot molecule). We show that the exciton state decays to the ground state of the QDM via a combination of the Rabi rotation and exponential decay. For moderately spaced dots this process takes place on a picosecond time scale.

G. S. Muanza

Recent searches for non-SUSY exotics in $p\bar{p}$ collisions at a center-of-mass energy of 1.96 TeV at the Tevatron Run II are reported. The emphasis is put on the results of model-driven analyses which were updated to the full Run IIA datasets corresponding to integrated luminosities of about 1 $fb^{-1}$.

P. Machnikowski

A two-photon process leading to coherent transitions between the two circularly polarized exciton states in a quantum dot is studied. It is shown that optical flipping of the exciton polarization is possible with picosecond laser pulses. The process is closely related to two-photon Rabi oscillations of a biexciton but it is much more stable against shifts of

Christos Charmousis, Ruth Gregory, Antonio Padilla

We show how to construct consistent braneworld models which exhibit late time acceleration. Unlike self-acceleration, which has a de Sitter vacuum state, our models have the standard Minkowski vacuum and accelerate only in the presence of matter, which we dub ``stealth-acceleration''. We use an effective action for the brane which includes an induced

Massimo Ricotti, Andrew Pontzen, Matteo Viel

Several recent studies suggest a correlation between dark matter halo mass and the shape of the density profile. We re-analyze simulations from Ricotti (2003) in which such a correlation was proposed. We use a standard analysis of the halo density profiles and compare the old simulations to new ones performed with Gadget2, including higher resolution runs. W

Herbert Spohn

We explain how the kinetic theory of L. Boltzmann is applied to weakly nonlinear wave equations.

R. J. Young, S. J. Dewhurst, R. M. Stevenson, A. J. Shields

Correlation between the rectilinear polarisations of the photons emitted from the biexciton decay in a single quantum dot is investigated in a device which allows the charge-state of the dot to be controlled. Optimising emission from the neutral exciton states maximises the operating efficiency of the biexciton decay. This is important for single dot applica

Jan Conrad

The Large Area Telescope (LAT), one of two instruments on the Gamma-ray Large Area Space Telescope (GLAST) mission, scheduled for launch by NASA in 2007, is an imaging, wide field-of-view, high-energy gamma-ray telescope, covering the approximate energy range from 20 MeV to more than 300 GeV. Annihilation of Weakly Interacting Massive Particles (WIMP), predi

Kristian Harder

The increasing size of the data samples recorded by the CDF and DO experiments at the Tevatron enables studies of a wide range of processes involving the electroweak bosons W and Z. Single boson production is now looked at in terms of differential cross sections such as rapidity or transverse momentum dependence. Diboson production cross-sections are several

G. Brida, M. V. Chekhova, M. Genovese, L. A. Krivitsky

We study the frequency-angular lineshape for a phase-matched nonlinear process producing entangled states and show that there is a continuous variety of maximally-entangled states generated for different mismatch values within the natural bandwidth. Detailed considerations are made for two specific methods of polarization entanglement preparation, based on t

A. Dotter, B. Chaboyer, D. Jevremovic, E. Baron

The ACS Survey of Galactic Globular Clusters, an HST Treasury Project, will deliver high quality, homogeneous photometry of 65 globular clusters. This paper introduces a new collection of stellar evolution tracks and isochrones suitable for analyzing the ACS Survey data. Stellar evolution models were computed at [Fe/H]= -2.5, -2.0, -1.5, -1.0, -0.5, and 0; [

F. Glas, J. -C. Harmand, G. Patriarche

We develop a nucleation-based model to explain the formation of the wurtzite (WZ) crystalline phase during the vapor-liquid-solid growth of free-standing nanowires of zinc-blende (ZB) semiconductors. We first show that, in nanowires, nucleation generally occurs at the outer edge of the solid/liquid interface (the triple phase line) rather than elsewhere at t

Elizabeth Meckes

In this paper, explicit error bounds are derived in the approximation of rank $k$ projections of certain $n$-dimensional random vectors by standard $k$-dimensional Gaussian random vectors. The bounds are given in terms of $k$, $n$, and a basis of the $k$-dimensional space onto which we project. The random vectors considered are two generalizations of the cas

Lutz Mattner, Bero Roos

We prove optimal constant over root $n$ upper bounds for the maximal probabilities of $n$th convolution powers of discrete uniform distributions.

Jérôme Lelong

We study the almost sure convergence of randomly truncated stochastic algorithms. We present a new convergence theorem which extends the already known results by making vanish the classical condition on the noise terms. The aim of this work is to prove an almost sure convergence result of randomly truncated stochastic algorithms under easily verifiable condi

Ajay K. Pandey, Jean-Michel Nunzi

We implement and demonstrate a scheme that permits to drive electroluminescence with an extremely low turn-on voltage. The device behaves like compound semiconductors, in which the electroluminescence turn-on voltage is about the same as the open circuit voltage for the photovoltaic effect. However, the electroluminescence turn-on voltage is about half of th

C. Andreeva, S. Cartaleva, L. Petrov, S. M. Saltiel

Saturation effects affecting absorption and fluorescence spectra of an atomic vapor confined in an Extremely Thin Cell (cell thickness $L < 1 μm$) are investigated experimentally and theoretically. The study is performed on the $D_{2}$ line ($λ~= ~852 nm)$ of $Cs$ and concentrates on the two situations $L = λ/2$ and $L =λ$, the most contrasted ones with resp

M. Szymczak, A. Bartkiewicz, E. Gerard

We have observed the OH 1612-MHz maser emission towards the proto-planetary nebula candidate OH17.7-2.0 that underwent a very strong and unusual outburst in 2003. Phase-referencing data were obtained with the EVN in order to localize the outburst and to examine its possible causes. The majority of the emission comes from an incomplete spherical shell with in

Giorgos Fagas, James C. Greer

For investigation of electron transport on the nanoscale, a system possessing a simple to interpret electronic structure is composed of alkane chains bridging two electrodes via end groups; to date the majority of experiments and theoretical investigations on such structures have considered thiols bonding to gold electrodes. Recently experiments show that we

Askin Ankay, Arzu M. Ankay, E. Nihal Ercan

Dim radio-quiet neutron star (DRQNS) 1E 1207.4-5209 is one of the most heavily examined isolated neutron stars. Wide absorption lines were observed in its spectrum obtained by both XMM-Newton and Chandra X-ray satellites. These absorption lines can be interpreted as a principal frequency centered at 0.7 keV and its harmonics at 1.4, 2.1 and possibly 2.8 keV.

M. Maturi, L. Moscardini, P. Mazzotta, K. Dolag

The polarization sensitivity of the upcoming millimetric observatories will open new possibilities for studying the properties of galaxy clusters and for using them as powerful cosmological probes. For this reason it is necessary to investigate in detail the characteristics of the polarization signals produced by their highly ionized intra-cluster medium (IC

Ihor Lubashevsky, Rudolf Friedrich, Andrey Ushakov, Andreas Heuer

The paper is devoted to the construction of the superstatistical description for nonequilibrium Markovian systems. It is based on Kirchhoff&#39;s diagram technique and the assumption on the system under consideration to possess a wide variety of cycles with vanishing probability fluxes. The latter feature enables us to introduce equivalence classes called ch

Vojtech Kundrat, Milos Lokajicek, Ivo Vrkoc

The commonly used West and Yennie integral formula for the relative phase between the Coulomb and elastic hadronic amplitudes might be consistently applied to only if the hadronic amplitude had the constant ratio of the real to the imaginary parts al all kinematically allowed values of four momentum transfer squared.

Yuliya V. Martsynyuk

Linear structural error-in-variables models with univariate observations are revisited for studying modified least squares estimators of the slope and intercept. New marginal central limit theorems (CLT&#39;s) are established for these estimators, assuming the existence of four moments for the measurement errors and that the explanatory variables are in the

Andrei Zelevinsky

This is an extended abstract of my talk at the Oberwolfach Workshop &#34;Algebraic Groups&#34; (April 22 - 28, 2007). It is based on a joint work with H.Derksen and J.Weyman (arXiv:0704.0649v2 [math.RA]).

S. Valencia, A. Gaupp, W. Gudat, Ll. Abad

Surface magnetic properties of perovskite manganites have been a recurrent topic during last years since they play a major role in the implementation of magnetoelectronic devices. Magneto-optical techniques, such as X-ray magnetic circular dichroism, turn out to be a very efficient tool to study surface magnetism due to their sensitivity to magnetic and chem

Valeria Banica, Luis Vega

In this article we will study the initial value problem for some Schrödinger equations with Diraclike initial data and therefore with infinite L2 mass, obtaining positive results for subcritical nonlinearities. In the critical case and in one dimension we prove that after some renormalization the corresponding solution has finite energy. This allows us to co

Hagai Netzer, Dieter Lutz, Mario Schweitzer, Alessandra Contursi

This is the second paper studying the QSOs in the spitzer QUEST sample. Previously we presented new PAH measurements and argued that most of the observed far infrared (FIR) radiation is due to star-forming activity. Here we present spectral energy distributions (SEDs) by supplementing our data with optical, NIR and FIR observations. We define two sub-groups

Alexandros Alexakis

A non-local cascade model for anisotropic MHD turbulence in the presence of a guiding magnetic field is proposed. The model takes into account that (a) energy cascades in an anisotropic manner and as a result a different estimate for the cascade rate in the direction parallel and perpendicular to the guiding field is made. (b) the interactions that result in

Herbert Spohn

We discuss energy current correlations in thermal equilibrium and point out the linkage to the fluctuating Peierls equation.

Roman Cherniha, Oleksii Pliukhin

In the first part of this paper math-ph/0612078, a complete description of Q-conditional symmetries for two classes of reaction-diffusion-convection equations with power diffusivities is derived. It was shown that all the known results for reaction-diffusion equations with power diffusivities follow as particular cases from those obtained in math-ph/0612078

David Gfeller, Paolo De los Rios

Reducing the complexity of large systems described as complex networks is key to understand them and a crucial issue is to know which properties of the initial system are preserved in the reduced one. Here we use random walks to design a coarse-graining scheme for complex networks. By construction the coarse-graining preserves the slow modes of the walk, whi

Padeli P. Papadopoulos, Kate G. Isaak, Paul P. van der Werf

We report on detections of the high-excitation CO J=6-5, J=4-3 lines in Mrk231, a prototypical Ultra Luminous Infrared Galaxy (ULIRG) and Seyfert 1 QSO. These observations are combined with CO J=3-2, HCN J=4-3 (this work), and CO J=2-1, J=1-0, 13CO J=2-1, HCN J=1-0 measurements taken from the literature to provide better constraints on the properties of the

John Southworth, A. Schwope, B. T. Gaensicke, M Schreiber

KUV 23182+1007 was identified as a blue object in the Kiso UV Survey in the 1980s. Classification-dispersion spectroscopy showed a featureless continuum except for a strong emission line in the region of He II 4686 A. This is a hallmark of the rare AM CVn class of cataclysmic variable star, so we have obtained a high-S/N blue spectrum of this object to check

A. Dotter, B. Chaboyer, J. W. Ferguson, H. -c. Lee

Integrated light from distant galaxies is often compared to stellar population models via the equivalent widths of spectral features--spectral indices--whose strengths rely on the abundances of one or more elements. Such comparisons hinge not only on the overall metal abundance but also on relative abundances. Studies have examined the influence of individua

Herbert Spohn

The current status of the derivation of kinetic equations from quantum many-particle dynamics is reviewed.

Herbert Spohn

We consider the quantum scattering from a random potential of strength $λ^{1/2}$ and with a support on the scale of the mean free path, which is of order $λ^{-1}$. On the basis of maximally crossed diagrams we provide a concise formula for the backscattering rate in terms of the Green&#39;s function for the kinetic Boltzmann equation. We briefly discuss the

Abiy G. Tekola

Spherically symmetric dark energy structures are investigated in the framework of a generalized Chaplygin gas (GCG), which has an equation of state of the form $P = - A/ρ^α} $. We also study these in a modified GCG equation of state, which includes a matter term, i.e. $P = σ^{2} ρ- A/ρ^α$. The results of the latter are then compared with some observational d

F. Carrier, P. Eggenberger, J. C. Leyder, Y. Debernardi

The goal is to test the structure of hot metallic stars, and in particular the structure of a near-surface convection zone using asteroseismic measurements. Indeed, stellar models including a detailed treatement of the radiative diffusion predict the existence of a near-surface convection zone in order to correctly reproduce the anomalies in surface abundanc

F. Daniel, J. Cernicharo, E. Roueff, M. Gerin

We present observations of the $J$=1--0, 2--1, and 3--2 rotational transitions of N$_2$H$^+$ and N$_2$D$^+$ towards a sample of prototypical dark clouds. The data have been interpreted using non--local radiative transfer models.

Raoul Zimmermann

A general reconstruction and calibration procedure for tracking and wire position determination of the OPERA drift tubes is presented. The mathematics of the pattern recognition and the track fit are explained.

J. Schepers, W. Veys

We show that for a hypersurface Batyrev&#39;s stringy E-function can be seen as a residue of the Hodge zeta function, a specialization of the motivic zeta function of Denef and Loeser. This is a nice application of inversion of adjunction. If an affine hypersurface is given by a polynomial that is non-degenerate with respect to its Newton polyhedron, then th

F. Carrier, H. Kjeldsen, T. R. Bedding, B. J. Brewer

Convection in stars excites resonant acoustic waves which depend on the sound speed inside the star, which in turn depends on properties of the stellar interior. Therefore, asteroseismology is an unrivaled method to probe the internal structure of a star. We made a seismic study of the metal-poor subgiant star nu Indi with the goal of constraining its interi

Matthias Krüger, Markus Rauscher

We investigate the non-equilibrium fluid structure mediated forces between two colloids driven through a suspension of mutually non-interacting Brownian particles as well as between a colloid and a wall in stationary situations. We solve the Smoluchowski equation in bispherical coordinates as well as with a method of reflections, both in linear approximation

E. J. Koop, A. I. Lerescu, J. Liu, B. J. van Wees

The spin degeneracy of the lowest subband that carries one-dimensional electron transport in quantum point contacts appears to be spontaneously lifted in zero magnetic field due to a phenomenon that is known as the 0.7 anomaly. We measured this energy splitting, and studied how it evolves into a splitting that is the sum of the Zeeman effect and a field-inde

P. Gibilisco, D. Imparato, T. Isola

Let $A_1,...,A_N$ be complex self-adjoint matrices and let $ρ$ be a density matrix. The Robertson uncertainty principle $$ det(Cov_ρ(A_h,A_j)) \geq det(- \frac{i}{2} Tr(ρ[A_h,A_j])) $$ gives a bound for the quantum generalized covariance in terms of the commutators $[A_h,A_j]$. The right side matrix is antisymmetric and therefore the bound is trivial (equal

Stefan Maubach, Han Peters

We introduce a class of polynomial maps that we call polynomial roots of powerseries, and show that automorphisms with this property generate the automorphism group in any dimension. In particular we determine generically which polynomial maps that preserve the origin are roots of powerseries. We study the one-dimensional case in greater depth.

Vladimir Shevelev

We put a new conjecture on primes from the point of view of its binary expansions and make a step towards justification.

Eugen Paal, Jyri Virkepu

A method for constructing Lagrangians for the Lie transformation groups is explained. As examples, the Lagrangians for real plane rotations and affine transformations of the real line are constructed.

M. R. Zapatero Osorio, E. L. Martin, V. J. S. Bejar, H. Bouy

(Abridged) We have obtained radial velocities of a sample of 18 ultracool dwarfs (M6.5-T8) using high-resolution, near-infrared spectra obtained with NIRSPEC and the Keck II telescope. We have confirmed that the radial velocity of Gl 570 D is coincident with that of the K-type primary star Gl 570 A, thus providing additional support for their true companions

Masayuki Tanaka, Takako Hoshi, Tadayuki Kodama, Nobunari Kashikawa

We report a definitive confirmation of a large-scale structure around the super rich cluster CL0016+1609 at z=0.55. We made spectroscopic follow-up observations with FOCAS on Subaru along the large filamentary structure identified in our previous photometric studies. We have confirmed the physical connection of the huge filament extending over 20 Mpc in the

Dimitar G. Stoyanov

The paper analyses volt-ampere characteristics of a planar vacuum diode with mono-energetic electrons, emitted by the cathode (an electron beam). The movement of the electron beam in the volume of the diode is described. An analytic dependence of the volt-ampere characteristics in an unlimited and limited by the field mode of the electron beam is derived.

Giuseppe Bimonte, Enrico Santamato

We derive new general expressions for the fluctuating electromagnetic field outside a homogeneous material surface. The analysis is based on general results from the thermodynamics of irreversible processes, and requires no consideration of the material interior, as it only uses knowledge of the reflection amplitudes for its surface. Therefore, our results a

Kourosh Nozari, Mehrnoush Mirzaei

In this paper, bound states energies and corresponding wave functions of H-shaped quantum wires are calculated numerically in the presence of external magnetic and electric fields and within the Landau gauge. With a suitable definition of external confinement potential, we present a numerical algorithm to calculate the profile of probability distribution of

Philippe Colomban, Raphaël Paquin

The use of micro-Raman spectroscopy, through chemical bond nano-scale probes, allows the changes in conformations (alpha helix -> beta sheet), chain orientation, disconnection of disulfide bonds (-20%) and the increase of intra and inter-chain distances during the strain to be distinguished. The combination of micro-Raman spectroscopy and a allows a quantita

Philippe Colomban, Gwénael Gouadec

The interest of micro and tip-enhanced Raman spectroscopy to analyze nanosized and nanostructured materials, chiefly semiconductors, oxides and pristine or functionalized carbon nanotubes, is reviewed at the light of the contributions to this special issue. Particular attention is paid to the fact that chemical reactions, size or shape distribution, defects,

A. G. Swartz, J. B. Kalmbach, J. Olson, R. J. Zieve

We measure stability of two-dimensional granular mixtures in a rotating drum and relate grain configurations to stability. For our system, the smaller but smoother grains cluster near the center of the drum, while the larger, rougher grains remain near the outer edge. One consequence of the size segregation is that the smaller grains heavily influence the st

Wen-Li Yang, Yao-Zhong Zhang

The multiple reference state structure of the $\Z_n$ Belavin model with non-diagonal boundary terms is discovered. It is found that there exist $n$ reference states, each of them yields a set of eigenvalues and Bethe Ansatz equations of the transfer matrix. These $n$ sets of eigenvalues together constitute the complete spectrum of the model. In the quasi-cla

Vishnu M. Bannur

We investigate fully nonlinear, non-Abelian excitations of quark-antiquark plasma, using relativistic fluid theory in cold plasma approximation. There are mainly three important nonlinearities, coming from various sources such as non-Abelian interactions of Yang-Mills (YM) fields, Wong&#39;s color dynamics and plasma nonlinearity, in our model. By neglecting

Satoru Odake, Ryu Sasaki

Exact Heisenberg operator solutions for independent `sinusoidal coordinates&#39; as many as the degree of freedom are derived for typical exactly solvable multi-particle quantum mechanical systems, the Calogero systems based on any root system. These Heisenberg operator solutions also present the explicit forms of the annihilation-creation operators for vari

Saugata Ghosh

We present an iterative technique to obtain skew-orthogonal polynomials with quartic weight, arising in the study of symplectic ensembles of random matrices.

M. Metcalfe, E. Boaknin, V. Manucharyan, R. Vijay

Dispersive readouts for superconducting qubits have the advantage of speed and minimal invasiveness. We have developed such an amplifier, the Cavity Bifurcation Amplifier (CBA) [10], and applied it to the readout of the quantronium qubit [2]. It consists of a Josephson junction embedded in a microwave on-chip resonator. In contrast with the Josephson bifurca