March 2006 arXiv papers — page 13

C. M. Baugh, C. G. Lacey, C. S. Frenk, G. L. Granato

We present a hierarchical galaxy formation model which can account for the number counts of sources detected through their emission at sub-millimetre wavelengths. The first stage in our approach is an ab initio calculation of the star formation histories for a representative sample of galaxies, which is carried out using the semi-analytical galaxy formation

R. C. Hickox, C. Jones, W. R. Forman, S. S. Murray

We examine the X-ray and infrared properties of galaxies and AGNs in the 9 square degree Bootes field, using data from the Chandra XBootes and Spitzer IRAC Shallow Surveys, as well as optical spectroscopy from the AGES survey. A sample of ~30,000 objects are detected in all four IRAC bands, of which ~2,000 are associated with X-ray sources. We also study X-r

W. Herbst, J. Eisloeffel, R. Mundt, A. Scholz

We review the current state of our knowledge concerning the rotation and angular momentum evolution of young stellar objects and brown dwarfs from a primarily observational view point. Periods are typically accurate to 1% and available for about 1700 stars and 30 brown dwarfs in young clusters. Discussion of angular momentum evolution also requires knowledge

D. R. Poelman, M. Spaans

A radiative transfer method for the treatment of molecular lines is presented. We apply this method to previous SWAS and ISO observations of water vapor in the source S140 in order to make models to plan for, and to interpret, HIFI data. Level populations are calculated with the use of a three-dimensional (multi-zone) escape probability method and with a lon

J. Ballot, R. A. Garcia, P. Lambert

In the context of future space-based asteroseismic missions, we have studied the problem of extracting the rotation speed and the rotation-axis inclination of solar-like stars from the expected data. We have focused on slow rotators (at most twice solar rotation speed), firstly because they constitute the most difficult case and secondly because some of the

Roland Diehl

With the SPI high-resolution spectrometer on INTEGRAL, new results have been obtained for long-lived radioactive 26Al and 60Fe in our Galaxy: 26Al sources apparently share the pattern of Galactic rotation in the inner Galaxy, and thus allow to estimate a total mass of 26Al in the Galaxy of 2.8 M_sol from the measured flux. 60Fe production in massive stars is

P. J. D. Mauas, C. Cacciari, L. Pasquini

In this study we test the possibility that the asymmetry in the profiles of the H-alpha and Ca II K lines in red giant stars is due to the presence of an active chromosphere rather than to mass loss. To this end, we compare line profiles computed using relevant model chromospheres to profiles of the H-alpha and Ca II K lines observed in five red giant stars

Marshall D. Perrin, Gaspard Duchene, Paul Kalas, James R. Graham

We have discovered an optically thick, edge-on circumstellar disk around a Herbig Ae star in the binary system PDS 144, providing the first intermediate-mass analog of HK Tau and similar T Tauris. This system consists of a V ~ 13 mag. primary and a fainter companion, with spectra of both stars showing evidence for circumstellar disks and accretion; both star

J. F. Macias-Perez, G. Lagache, B. Maffei, P. Ade

Archeops is a balloon--borne experiment widely inspired by the Planck satellite and by its High Frequency Instrument (HFI). It is mainly dedicated to measure the Cosmic Microwave Background (CMB) temperature anisotropies at high angular resolution (about 12 arcminutes) over a large fraction of the sky (around 30 %) in the millimetre and submillimetre range a

Signe Riemer-Sorensen, Steen H. Hansen, Kristian Pedersen

We consider the possibility of constraining decaying dark matter by looking out through the Milky Way halo. Specifically we use Chandra blank sky observations to constrain the parameter space of sterile neutrinos. We find that a broad band in parameter space is still open, leaving the sterile neutrino as an excellent dark matter candidate.

K. S. Cheng, D. O. Chernyshov, V. A. Dogiel

Both diffuse high energy gamma-rays and an extended electron-positron annihilation line emission have been observed in the Galactic Center (GC) region. Although X-ray observations indicate that the galactic black hole Sgr A$^*$ is inactive now, we suggest that Sgr A$^*$ can become active when a captured star is tidally disrupted and matter is accreted into t

Claudio Pagani, David C. Morris, Shiho Kobayashi, Takanori Sakamoto

The unique capability of the Swift satellite to perform a prompt and autonomous slew to a newly detected Gamma-Ray Burst (GRB) has yielded the discovery of interesting new properties of GRB X-ray afterglows, such as the steep early lightcurve decay and the frequent presence of flares detected up to a few hours after the GRB trigger. We present observations o

E. Egami, G. H. Rieke, J. R. Rigby, C. Papovich

We are currently undertaking a Spitzer GTO program to image ~30 massive lensing clusters at moderate redshift with both IRAC and MIPS. By taking advantage of the gravitatinoal lensing power of these clusters, we will study the population of faint galaxies that are below the nominal Spitzer detection limits. Here, we present a few examples of our science prog

E. Egami, K. A. Misselt, G. H. Rieke, M. W. Wise

We have studied the infrared properties of the brightest cluster galaxies (BCGs) located in the cores of X-ray-luminous clusters at 0.15 < z < 0.35. The majority of the BCGs are not particularly infrared-luminous compared with other massive early-type galaxies, suggesting that the cluster environment has little influence on the infrared luminosities of the B

A. Nava, D. Casebeer, R. B. C. Henry, D. Jevremovic

We show that in order to minimize the uncertainties in the N and O abundances of low mass, low metallicity (O/H less than or equal to solar/5) emission-line galaxies, it is necessary to employ separate parameterizations for inferring Te[N II] and Te[O II] from Te[O III]. In addition, we show that for the above systems, the ionization correction factor (ICF)

Philip Kaaret, Melanie G. Simet, Cornelia C. Lang

The ultraluminous x-ray source (ULX) in the galaxy M82 has been identified as a possible intermediate-mass black hole. We have found that the x-ray flux from M82 is modulated with a peak-to-peak amplitude corresponding to an isotropic luminosity of 2.4x10^40 erg/s in M82 and a period of 62.0 +/- 2.5 days, which we interpret as the orbital period of the ULX b

Ryan O. Milligan, Peter T. Gallagher, Mihalis Mathioudakis, Francis P. Keenan

Observational evidence for gentle chromospheric evaporation during the impulsive phase of a C9.1 solar flare is presented using data from the Reuven Ramaty High-Energy Solar Spectroscopic Imager and the Coronal Diagnostic Spectrometer on board the Solar and Heliospheric Observatory. Until now, evidence for gentle evaporation has often been reported during th

Marc Henneaux, Cristian Martinez, Ricardo Troncoso, Jorge Zanelli

We examine anti-de Sitter gravity minimally coupled to a self-interacting scalar field in $D\geq 4$ dimensions when the mass of the scalar field is in the range $m_{\ast}^{2}\leq m^{2}<m_{\ast} ^{2}+l^{-2}$. Here, $l$ is the AdS radius, and $m_{\ast}^{2}$ is the Breitenlohner-Freedman mass. We show that even though the scalar field generically has a slow fal

Jong-Hak Woo, Tommaso Treu, Matthew A. Malkan, Roger D. Blandford

We test the evolution of the correlation between black hole mass and bulge velocity dispersion (M$_{\rm BH}-σ$), using a carefully selected sample of 14 Seyfert 1 galaxies at $z=0.36\pm0.01$. We measure velocity dispersion from stellar absorption lines around Mgb (5175Å) and Fe (5270Å) using high S/N Keck spectra, and estimate black hole mass from the H$β$ l

Nandinii Barbosa-Cendejas, Alfredo Herrera-Aguilar

We consider the generation of thick brane configurations in a pure geometric Weyl integrable 5D space time which constitutes a non-Riemannian generalization of Kaluza-Klein (KK) theory. In this framework, we show how 4D gravity can be localized on a scalar thick brane which does not necessarily respect reflection symmetry, generalizing in this way several pr

Chueng-Ryong Ji, Yuriy Mishchenko, Anatoly Radyushkin

We discuss the higher Fock state (q \bar q g) contributions to the nonzero value of the pion GPD at the crossover point x = zeta between the DGLAP and ERBL regions. Using the phenomenological light-front constituent quark model, we confirm that the higher Fock state contributions indeed give a nonzero value of the GPD at the crossover point. Iterating the li

Hans-Christian Graf v. Bothmer, Kristian Ranestad

We use the BGG-correspondence to show that there are at most three possible Hilbert functions for smooth rational surfaces of degree 11 and sectional genus 11. Surfaces with one of these Hilbert functions have been classified by Popescu. The classification for a second one is done in this paper. For the third Hilbert function the classification is still open

Leon Karpa, Martin Weitz

Electromagnetically induced transparency allows for light transmission through dense atomic media by means of quantum interference. Media exhibiting electromagnetically induced transparency have very interesting properties, such as extremely slow group velocities. Associated with the slow light propagation are quasiparticles, the so-called dark polaritons, w

Aristophanes Dimakis, Folkert Muller-Hoissen

Using deformations of associative products, derivative nonlinear Schrodinger (DNLS) hierarchies are recovered as AKNS-type hierarchies. Since the latter can also be formulated as Gelfand-Dickey-type Lax hierarchies, a recently developed method to obtain &#39;functional representations&#39; can be applied. We actually consider hierarchies with dependent varia

Francois Vernay, Arnaud Ralko, Federico Becca, Frederic Mila

Starting from the mean-field solution of a spin-orbital model of LiNiO$_2$, we derive an effective quantum dimer model (QDM) that lives on the triangular lattice and contains kinetic terms acting on 4-site plaquettes and 6-site loops. Using numerical exact diagonalizations and Green&#39;s function Monte Carlo simulations, we show that the competition between

Julien Chabé, Hans Lignier, Pascal Szriftgiser, Jean Claude Garreau

We study the peformances of Raman velocimetry applied to laser-cooled, spin-polarized, cesium atoms. Atoms are optically pumped into the F=4, m=0 ground-state Zeeman sublevel, which is insensitive to magnetic perturbations. High resolution Raman stimulated spectroscopy is shown to produce Fourier-limited lines, allowing, in realistic experimental conditions,

Gustavo Rigolin, Thiago R. de Oliveira, Marcos C. de Oliveira

We formalize and extend an operational multipartite entanglement measure introduced by T. R. Oliveira, G. Rigolin, and M. C. de Oliveira, Phys. Rev. A 73, 010305(R) (2006), through the generalization of global entanglement (GE) [D. A. Meyer and N. R. Wallach, J. Math. Phys. 43, 4273 (2002)]. Contrarily to GE the main feature of this measure lies in the fact

Geoffrey T. Bodwin, Daekyoung Kang, Jungil Lee

We present two methods for computing dimensionally-regulated NRQCD heavy-quarkonium matrix elements that are related to the second derivative of the heavy-quarkonium wave function at the origin. The first method makes use of a hard-cutoff regulator as an intermediate step and requires knowledge only of the heavy-quarkonium wave function. It involves a signif

Marco Frasca

We show that a strongly perturbed quantum system, being a semiclassical system characterized by the Wigner-Kirkwood expansion for the propagator, has the same expansion for the eigenvalues as for the WKB series. The perturbation series is rederived by the duality principle in perturbation theory.

Claus Hertling, Christian Sevenheck

We study a generalization of Hodge structures which first appeared in the work of Cecotti and Vafa. It consists of twistors, that is, holomorphic vector bundles on P^1, with additional structure, a flat connection on C^*, a real subbundle and a pairing. We call these objects TERP-structures. We generalize to TERP-structures a correspondence of Cattani, Kapla

The BABAR Collaboration, B. Aubert

We present a measurement of the branching fraction of the decay B0 --> a1(1260)^{+-} pi^{-+} with a1(1260)^{+-} --> pi^{-+} pi^{+-} pi^{+-}. The data sample consists of 218 million B B-bar pairs collected at the Y(4S) resonance and recorded by the BaBar detector at the PEP-II asymmetric-energy e+e- collider at SLAC. The analysis is based on unbinned multivar

Pierre Carrier, Stefan Rohra, Andreas Goerling

We present a general scheme for treating the integrable singular terms within exact exchange (EXX) Kohn-Sham or Hartree-Fock (HF) methods for periodic solids. We show that the singularity corrections for treating these divergencies depend only on the total number and the positions of k-points and on the lattice vectors, in particular the unit cell volume, bu

A. Sandage, G. A. Tammann, A. Saha, B. Reindl

This is the fifth and final summary paper of our 15 year program using the Hubble Space Telescope (HST) to determine the Hubble constant using Type Ia supernovae, calibrated with Cepheid variables in nearby galaxies that hosted them. Several developments not contemplated at the start of the program in 1990 have made it necessary to put the summary on H_0 on

Goren Gordon, Gustavo Rigolin

We present two quantum state sharing protocols where the channels are not maximally entangled states. By properly choosing the measurement basis it is possible to achieve unity fidelity transfer of the state if the parties collaborate. We also show that contrary to the protocols where we have maximally entangled channels these protocols are probabilistic. We

A. Günther, S. Kraft, C. Zimmermann, J. Fortágh

We report the phase coherent splitting of Bose-Einstein condensates by means of a phase grating produced near the surface of a micro-electronic chip. A lattice potential with a period of $4μ$m is generated by the superposition of static and oscillating magnetic fields. Precise control of the diffraction is achieved by controlling the currents in the integrat

Benjamin Klopsch, Christopher Voll

We study symmetries enjoyed by the polynomials enumerating non-degenerate flags in finite vector spaces, equipped with a non-degenerate alternating bilinear, hermitian or quadratic form. To this end we introduce Igusa-type rational functions encoding these polynomials and prove that they satisfy certain functional equations. Some of our results are achieved

Nadia L. Zakamska, Michael A. Strauss, Julian H. Krolik, Susan E. Ridgway

Type II quasars are luminous Active Galactic Nuclei whose centers are obscured by large amounts of gas and dust. In this paper we present 3-band HST images of nine type II quasars with redshifts 0.2 < z < 0.4 selected from the Sloan Digital Sky Survey based on their emission line properties. The intrinsic luminosities of these AGN are estimated to be -24 > M

Natalia Pavlenko, Thilo Kopp

For heterostructures of ultrathin, strongly correlated copper-oxide films and dielectric perovskite layers, we predict inhomogeneous electronic interface states. Our study is based on an extended Hubbard model for the cuprate film. The interface is implemented by a coupling to the electron and phonon degrees of freedom of the dielectric oxide layer. We find

I. Bombaci, G. Lugones, I. Vidana

We study the nucleation of quark matter drops at the center of cold deleptonized neutron stars. This is relevant in the determination of the critical mass $M_{cr}$ of hadronic stars above which it is possible a transition to a quark star (strange or hybrid). We investigate the dependence of $M_{cr}$ upon the parameters of the quark model (the Bag constant $B

H. E. Caicedo-Ortiz, S. T. Perez-Merchancano

In this work, the exchange energy J for a system of two laterally-coupled quantum dots, each one with an electron, is calculated analytically and in a detailed form, considering them as hydrogen-like atoms, under the Heitler-London approach. The atomic orbitals, associated to each quantum dot, are obtained from translation relations, as functions of the Fock

J. Hemberger, T. Rudolf, H. -A. Krug von Nidda, F. Mayr

Utilizing magnetic susceptibility, specific heat, thermal expansion and IR spectroscopy we provide experimental evidence that the two subsequent antiferromagnetic transitions in ZnCr_2S_4 at T_N1 = 15 K and T_N2= 8 K are accompanied by significant thermal and phonon anomalies. The anomaly at T_N2 reveals a strong temperature hysteresis typical for a first-or

Bin Shang

In this summary we discuss two new algorithms for Grover&#39;s unsorted database search problem that claimed to have reached exponential speedup over Grover&#39;s original algorithm. One is in the quantum setting with &#34;power queries&#34; that allow for exponential reduction in the number of queries over Grover&#39;s original algorithm with &#34;bit queri

A. Kotzinian, B. Parsamyan, A. Prokudin

In the leading order of QCD parton model of Semi Inclusive Deep Inelastic Scattering (SIDIS) the double spin asymmetry $A_{LT}$ arises due to the longitudinal polarization of quarks in the transversely polarized nucleon. The corresponding $k_T^2$ weighted distribution function $g^{(1)}_{1T}$ can be related to ordinary helicity distribution $g_1(x)$ measured

Andre Henriques

Given an n-term L-infinity algebra L, we construct a Kan simplicial manifold which we think of as the &#39;Lie n-group&#39; integrating L. This extends work of Getzler math.AT/0404003 . In the case of an ordinary Lie algebra, our construction gives the simplicial classifying space of the corresponding simply connect Lie group. In the case of the string Lie 2

Nikolay Prokof&#39;ev, Boris Svistunov

This paper has been withdrawn by the authors, due to a possible flaw in its logic. Namely, it has been taken for granted that the the structure of regular part of Helmholtz free energy is insensitive to the sign of the specific heat exponent.

Sung-Sik Lee, Patrick A. Lee

Using Monte Carlo simulation, we studied fractionalized phases in a model of exciton bose condensate and found evidence for an emergent photon in a finite size system. The fractionalized phase is a meta-stable Coulomb phase where an emergent photon arises as a gapless collective excitation of the excitons. We also studied a possibility of spiral* phase where

T. Roy Choudhury, A. Ferrara

The recent release of data on (i) high redshift source counts from NICMOS HUDF, and (ii) electron scattering optical depth from 3-year WMAP, require a re-examination of reionization scenarios. Using an improved self-consistent model, based on Choudhury & Ferrara (2005), we determine the range of reionization histories which can match a wide variety of data s

G. E. Volovik

Ripplons -- gravity-capillary waves on the free surface of a liquid or at the interfaces between two superfluids -- are the most favourable excitations for simulation of the general-relativistic effects related to horizons and ergoregions. The white-hole horizon for the ``relativistic'' ripplons at the surface of the shallow liquid is easily simulated using

Charles Hellaby

We point out that the mass of the cosmos on gigaparsec scales can be measured, owing to the unique geometric role of the maximum in the areal radius. Unlike all other points on the past null cone, this maximum has an associated mass, which can be calculated with very few assumptions about the cosmological model, providing a measurable characteristic of our c

Johannes Kofler, Caslav Brukner

What can we learn about entanglement between individual particles in macroscopic samples by observing only the collective properties of the ensembles? Using only a few experimentally feasible collective properties, we establish an entanglement measure between two samples of spin-1/2 particles (as representatives of two-dimensional quantum systems). This is a

Zheng Ze Ma

We study the microcausality of free Dirac field on noncommutative spacetime. We calculate the vacuum and non-vacuum state expectation values for the Moyal commutator $[\barψ_α(x)\starψ_β(x),\barψ_ σ(x^{\prime})\starψ_τ(x^{\prime})]_{\star}$ of Dirac field on noncommutative spacetime. We find that they do not vanish for some cases of the indexes for an arbitr

Julien Dumont, Philippe Loubaton, Samson Lasaulce

We determine the capacity-achieving input covariance matrices for coherent block-fading correlated MIMO Rician channels. In contrast with the Rayleigh and uncorrelated Rician cases, no closed-form expressions for the eigenvectors of the optimum input covariance matrix are available. Both the eigenvectors and eigenvalues have to be evaluated by using numerica

L. E. Svistov, A. I. Smirnov, L. A. Prozorova, O. A. Petrenko

We have studied the magnetic and thermodynamic properties as well as the NMR spectra of the Heisenberg antiferromagnet RbFe(MoO4)2. The observed temperature dependence of the order parameter, the critical indices and the overall magnetic H-T phase diagram are all in a good agreement with the theoretical predictions for a 2D XY model. The temperature dependen

Andrew R. Wade

Under the unifying umbrella of a general result of Penrose & Yukich [Ann. Appl. Probab., (2003) 13, 277--303] we give laws of large numbers (in the $L^p$ sense) for the total power-weighted length of several nearest-neighbour type graphs on random point sets in $\R^d$, $d\in\N$. Some of these results are known; some are new. We give limiting constants explic

Zong-Kuan Guo, Zong-Hong Zhu, J. S. Alcaniz, Yuan-Zhong Zhang

Although there is mounting observational evidence that the expansion of our universe is undergoing a late-time acceleration, the mechanism for this acceleration is yet unknown. In the so-called Dvali-Gabadadze-Porrati (DGP) model this phenomena is attributed to gravitational leakage into extra dimensions. In this work, we mainly focus our attention to the co

Santiago Peris

In the large-Nc limit of QCD, the chiral expansion of the vacuum polarization at low energies determines the whole function at any arbitrarily large (but finite) energy. This result is an immediate consequence of the Theory of Pade Approximants to Stieltjes functions.

A. R. Balabekyan, A. S. Danagulyan, J. R. Drnoyan, N. A. Demekhina

The recoil properties of the product nuclei from the interaction of 3.65 GeV/nucleon protons and deuterons with $^{118}Sn$ target have been studied by the method of catching foils on the beams of LHE JINR. The mathematical formalism of the standard two step vector model was used for the analysis of experimental results. The obtained results for the protons a

M. Ablikim

Results are presented on J/psi radiative decays to pi^+pi^- and pi^0pi^0 based on a sample of 58M J/psi events taken with the BESII detector. Partial wave analyses are carried out using the relativistic covariant tensor amplitude method in the 1.0 to 2.3 GeV/c^2 pipi mass range. There are conspicuous peaks due to the f_2(1270) and two 0^++ states in the 1.45

J. H. Jiang, M. Q. Weng, M. W. Wu

We investigate the effects of the intense terahertz laser field and the spin-orbit coupling on single electron spin in a quantum dot. The laser field and the spin-orbit coupling can strongly affect the electron density of states and can excite a magnetic moment. The direction of the magnetic moment depends on the symmetries of the system, and its amplitude c

Riccardo Barbieri, Lawrence J. Hall, Vyacheslav S. Rychkov

The quadratic divergences of the Higgs mass may be cancelled either accidentally or by the exchange of some new particles. Alternatively its impact on naturalness may be weakened by raising the Higgs mass, which requires changing the Standard Model below its natural cut-off. We show in detail how this can be achieved, while preserving perturbativity and cons

Geoffrey T. Bodwin, Daekyoung Kang, Jungil Lee

It has been suggested in Ref. [A. E. Bondar and V. L. Chernyak, Phys. Lett. B 612, 215 (2005)] that the disagreement between theoretical calculations and experimental observations for the rate for the process e+ e- -> J/psi + eta_c at the B factories might be resolved by using the light-cone method to take into account the relative momentum of the heavy-quar

E. V. Deviatov, A. A. Kapustin, V. T. Dolgopolov, A. Lorke

We experimentally study equilibration between edge states, co-propagating at the edge of the fractional quantum Hall liquid, at high initial imbalances. We find an anomalous increase of the conductance between the fractional edge states at the filling factor $ν=2/5$ in comparison with the expected one for the model of independent edge states. We conclude tha

Xiaohong Zhao, J. M. Bai

The high efficiency of converting kinetic energy into gamma-rays estimated with late-time afterglows in Gamma-Ray Burst (GRB) phenomenon challenges the commonly accepted internal-shock model. However, the efficiency is still highly uncertain because it is sensitive to many effects. In this Letter we study the sideways expansion effect of jets on estimating t

Erhai Zhao, J. A. Sauls

We investigate spin transport in voltage-biased spin-active Josephson junctions. The interplay of spin filtering, spin mixing, and multiple Andreev reflection leads to nonlinear voltage dependence of the dc and ac spin current. We compute the voltage characteristics of the spin current (I_S) for superconductor-ferromagnet-superconductor (SFS) Josephson junct

Paul A. LaViolette

The novel physics methodology of subquantum kinetics predicted in 1980 that photons should blueshift their frequency at a rate that varies directly with negative gravitational potential, the rate of blueshifting for photons traveling between Earth and Jupiter having been estimated to average approximately (1.3 +/- 0.65) X 10^-18 s^-1, or (1.1 +/- 0.6) X 10^-

J. -B. Fouet, F. Mila, D. Clarke, H. Youk

Motivated by the ever-increasing experimental effort devoted to the properties of frustrated quantum magnets in a magnetic field, we present a careful and detailed theoretical analysis of a one-dimensional version of this problem, a frustrated ladder with a magnetization plateau at m=1/2. We show that even for purely isotropic Heisenberg interactions, the ma

Hiroshi Itoyama, Kazunobu Maruyoshi

We study a minimal model of U(N) gauged N=2 supergravity with one hypermultiplet parametrizing SO(4,1)/SO(4) quaternionic manifold. Local N=2 supersymmetry is known to be spontaneously broken to N=1 in the Higgs phase of U(1)_{graviphoton} \times U(1). Several properties are obtained of this model in the vacuum of unbroken SU(N) gauge group. In particular, w

Taras Panov

In the theory of algebraic group actions on affine varieties, the concept of a Kempf-Ness set is used to replace the categorical quotient by the quotient with respect to a maximal compact subgroup. By making use of the recent achievements of &#34;toric topology&#34; we show that an appropriate notion of a Kempf-Ness set exists for a class of algebraic torus

Cheng Chin, V. V. Flambaum

Scattering length, which can be measured in Bose-Einstein condensate and Feshbach molecule experiments, is extremely sensitive to the variation of fundamental constants, in particular, the electron-to-proton mass ratio (m_e/m_p or m_e/Lambda_{QCD}, where Lambda_{QCD} is the QCD scale). Based on single- and two-channel scattering model, we show how the variat

Jose Orlando Organista, M. Nowakowski, H. C. Rosu

We show in a rigorous way that Crum&#39;s result on equal eigenvalue spectrum of Sturm-Liouville problems can be obtained iteratively by successive Darboux transformations. It can be shown that all neighbouring Darboux-transformed potentials of higher order, u_{k} and u_{k+1}, satisfy the condition of shape invariance provided the original potential u does.

Jian-yu Lu

Limited-diffraction beams are a class of waves that may be localized in space and time. Theoretically, these beams are propagation invariant and can propagate to an infinite distance without spreading. In practice, when these beams are produced with wave sources of a finite aperture and energy, they have a very large depth of field, meaning that they can kee

D. Li, J. P. Chen, X. Li, H. Huang

Grover presented the phase-shift search by replacing the selective inversions by selective phase shifts of $π/3$. In this paper, we investigate the phase-shift search with general equal phase shifts. We show that for small uncertainties, the failure probability of the Phase-$π/3$ search is smaller than the general phase-shift search and for large uncertainti

S. V. Dmitriev, P. G. Kevrekidis, A. A. Sukhorukov, N. Yoshikawa

We derive a class of discrete nonlinear Schr{ö}dinger (DNLS) equations for general polynomial nonlinearity whose stationary solutions can be found from a reduced two-point algebraic problem. It is demonstrated that the derived class of discretizations contains subclasses conserving classical norm or a modified norm and classical momentum. These equations are

Kirill Melnikov, Frank Petriello

We compute the O(alpha_s^2) QCD corrections to the fully differential cross-section pp \to W X \to l νX, retaining all effects from spin correlations. The knowledge of these corrections makes it possible to calculate with high precision the W boson production rate and acceptance at the LHC, subject to realistic cuts on the lepton and missing energy distribut

P. G. Kevrekidis, S. V. Dmitriev, A. A. Sukhorukov

We demonstrate the systematic derivation of a class of discretizations of nonlinear Schr{\"o}dinger (NLS) equations for general polynomial nonlinearity whose stationary solutions can be found from a reduced two-point algebraic condition. We then focus on the cubic problem and illustrate how our class of models compares with the well-known discretizations suc

Shuichi Wakimoto, Hiroyuki Kimura, Masaki Fujita, Kazuyoshi Yamada

We report incommensurate diffuse (ICD) scattering appearing in the high-temperature-tetragonal (HTT) phase of La$_{2-x}$(Sr,Ba)$_{x}$CuO$_{4}$ with $0.07 \leq x \leq 0.20$ observed by the neutron diffraction technique. For all compositions, a sharp superlattice peak of the low-temperature-orthorhombic (LTO) structure is replaced by a pair of ICD peaks with t

M. Kindermann, P. W. Brouwer, A. J. Millis

We show that interference experiments can be used to identify the spin-incoherent regime of strongly interacting one-dimensional conductors. Two qualitative signatures of spin-incoherence are found: a strong magnetic field dependence of the interference contrast and an anomalous scaling of the interference contrast with the applied voltage, with a temperatur

Elena Gubankova, Andreas Schmitt, Frank Wilczek

Candidate homogeneous, isotropic superfluid or superconducting states of paired fermion species with different chemical potentials, can lead to quasiparticle excitation energies that vanish at either zero, one, or two spheres in momentum space. With no zeroes, we have a conventional BCS superconductor. The other two cases, ``gapless&#39;&#39; superconductors

Katsunori Kubo, Takashi Hotta

We propose a concept of superconductivity controlled by orbital degree of freedom taking CeMIn5 (M= Co, Rh, and Ir) as typical examples. A microscopic multiorbital model for CeMIn5 is analyzed by fluctuation exchange approximation. Even though the Fermi-surface structure is unchanged, the ground state is found to change significantly among paramagnetic, anti

Marcela Carena, Dan Hooper, Peter Skands

Searches for the Minimal Supersymmetric Standard Model (MSSM) Higgs bosons are among the most promising channels for exploring new physics at the Tevatron. In particular, interesting regions of large $\tan β$ and small $m_A$ are probed by searches for heavy neutral Higgs bosons, A and H, when they decay to $τ^+ τ^-$ and $b\bar{b}$. At the same time, direct s

JM Geremia

We present a deterministic approach based on continuous measurement and real-time quantum feedback control to prepare arbitrary photon number states of a cavity mode. The procedure passively monitors the number state actually achieved in each feedback stabilized measurement trajectory, thus providing a nondestructively verifiable photon source. The feasibili

H. Haeffner, W. Haensel, C. F. Roos, J. Benhelm

Among the various kinds of entangled states, the &#39;W state&#39; plays an important role as its entanglement is maximally persistent and robust even under particle loss. Such states are central as a resource in quantum information processing and multiparty quantum communication. Here we report the scalable and deterministic generation of four-, five-, six-

Takahito Tanimura, Daisuke Akamatsu, Yoshihiko Yokoi, Akira Furusawa

We report generation of a continuous-wave squeezed vacuum resonant on the Rb D_1 line (795 nm) using periodically poled KTiOPO_4 (PPKTP) crystals. With a frequency doubler and an optical parametric oscillator based on PPKTP crystals, we observed a squeezing level of -2.75 +- 0.14 dB and an anti-squeezing level of +7.00 +- 0.13 dB. This system could be utiliz

Raul O. Vallejos, P. R. del Santoro, A. M. Ozorio de Almeida

The characteristic stretching and squeezing of chaotic motion is linearized within the finite number of phase space domains which subdivide a classical baker map. Tensor products of such maps are also chaotic, but a more interesting generalized baker map arises if the stacking orders for the factor maps are allowed to interact. These maps are readily quantiz

Ali Ahanj, Pramod Joag

We give a classical protocol to exactly simulate quantum correlations implied by a spin $s$ singlet state for the infinite sequence of \textit{integer} spin $s={1,4,13,...}$ satisfying $(2s+1)=3^{n}$,where $n$ is a positive integer.The required amount of communication is found to increase as $log_{3}d^{2}$ where $d=2s+1$ is the dimension of the spin $s$ Hilb

H. Nikolic

The many-fingered time (MFT) formulation of many-particle quantum mechanics and quantum field theory is a natural framework that overcomes the problem of &#34;instantaneous collapse&#34; in entangled systems that exhibit nonlocalities. The corresponding Bohmian interpretation can also be formulated in terms of MFT beables, which alleviates the problem of ins

Metod Saniga, Michel Planat, Milan Minarovjech

In 1993, Mermin (Rev. Mod. Phys. 65, 803--815) gave lucid and strikingly simple proofs of the Bell-Kochen-Specker (BKS) theorem in Hilbert spaces of dimensions four and eight by making use of what has since been referred to as the Mermin(-Peres) &#34;magic square&#34; and the Mermin pentagram, respectively. The former is a $3 \times 3$ array of nine observab

Sameer M. Ikhdair, Ramazan Sever

A new approximation formalism is applied to study the bound states of the Hellmann potential, which represents the superposition of the attractive Coulomb potential $-a/r$ and the Yukawa potential $b\exp (-δr)/r$ of arbitrary strength $b$ and screening parameter $δ$. Although the analytic expressions for the energy eigenvalues $E_{n,l\text{}}$ yield quite ac

Eugeniy E. Mikhailov, Vladimir A. Sautenkov, Yuri V. Rostovtsev, Aihua Zhang

We have studied the transmission of an optically thick Rb vapor that is illuminated by monochromatic and noise broaden laser fields in Lambda configuration. The spectral width of the beat signal between the two fields after transmission through the atomic medium is more than 1000 times narrower than the spectral width of this signal before the medium.

Vivien M Kendon, William J Munro

Entanglement has been termed a critical resource for quantum information processing and is thought to be the reason that certain quantum algorithms, such as Shor&#39;s factoring algorithm, can achieve exponentially better performance than their classical counterparts. The nature of this resource is still not fully understood: here we use numerical simulation

K. Luz-Burgoa, S. Moss de Oliveira, Veit Schwämmle, J. S. Sá Martins

We investigate the macroscopic effects of the ingredients that drive the origin of species through sympatric speciation. In our model, sympatric speciation is obtained as we tune up the strength of competition between individuals with different phenotypes. As a function of this control parameter, we can characterize, through the behavior of a macroscopic ord

V. A. Kuz&#39;menko

The experiments with weak collinear probe pulses for time reversal noninvariance study in optics are proposed and discussed.

A. D. Boardman, K. Marinov

An expression for the electromagnetic field energy density in a dispersive, lossy, left-handed metamaterial, consisting of an array of split-ring resonators and an array of wires is derived. An electromagnetic field with general time-dependence is considered. The outcome is compared with previously published results. In the absence of losses, agreement with

Carsten Henkel, Karl Joulain

The coherence length of the thermal electromagnetic field near a planar surface has a minimum value related to the nonlocal dielectric response of the material. We perform two model calculations of the electric energy density and the field&#39;s degree of spatial coherence. Above a polar crystal, the lattice constant gives the minimum coherence length. It al

S. Cht. Mavrodiev, L. Pekevski

The imminent WHEN earthquake predictions are based on the correlation between geomagnetic quakes and the incoming minimum (or maximum) of tidal gravitational potential. The probability time window for the incoming earthquake is for the tidal minimum approximately one day and for the maximum- two days. The statistic evidence for reliability is based on of dis

G. Tibely, J. -P. Onnela, J. Saramaki, K. Kaski

We construct a correlation matrix based financial network for a set of New York Stock Exchange (NYSE) traded stocks with stocks corresponding to nodes and the links between them added one after the other, according to the strength of the correlation between the nodes. The eigenvalue spectrum of the correlation matrix reflects the structure of the market, whi

R. E. Benestad

The proposition that the tropical cyclogenesis increases with the size of the warm pool, the area enclosed by the 26C SST isotherm, is tested by comparing the seasonal variation of the warm pool area with the seasonality of the number of tropical cyclones. A non-linear relationship of high statistical significance is found between the area and the number of

Marcis Auzinsh, Kaspars Blushs, Ruvin Ferber, Florian Gahbauer

We report the experimental observation of alignment to orientation conversion in the 7D_3/2 and 9D_3/2 states of Cs in the presence of an external dc electric field, and without the influence of magnetic fields or atomic collisions. Initial alignment of angular momentum states was created by two-step excitation with linearly polarized laser radiation. The ap

M. Risch

In heavy traffic with congested roadway the maximum traffic flow also depends on length of cars. This is deduced in a simple derivation suited for classroom demonstration as well as homework. The resulting equation demonstrates a new relation to an apparently unrelated area of physics, the maximum ship velocity (hull speed) and explains why traffic is someti

V. Chiochia, E. Alagoz, M. Swartz

In this paper a detailed simulation of irradiated pixel sensors was used to investigate the effects of radiation damage on charge sharing and position determination. The simulation implements a model of radiation damage by including two defect levels with opposite charge states and trapping of charge carriers. We show that charge sharing functions extracted