November 2001 arXiv papers — page 9

Klaus Morawetz

Using the Bethe-Salpeter equation including high electric fields, the dependence of the critical temperature of onsetting superconductivity on the applied field is calculated analytically. The critical temperature of pairing is shown to increase with the applied field strength. This is a new field effect and could contribute to the explanation of recent expe

H. Chamati

The finite-size critical properties of the ${\cal O}(n)$ vector $ϕ^4$ model, with long-range interaction decaying algebraically with the interparticle distance $r$ like $r^{-d-σ}$, are investigated. The system is confined to a finite geometry subject to periodic boundary condition. Special attention is paid to the finite-size correction to the bulk susceptib

John F. Dobson, Jun Wang, Tim Gould

We generalize the uniform-gas correlation energy formalism of Singwi, Tosi, Land and Sjolander to the case of an arbitrary inhomogeneous many-particle system. For jellium slabs of finite thickness with a self-consistent LDA groundstate Kohn-Sham potential as input, our numerical results for the correlation energy agree well with diffusion Monte Carlo results

Justin R. David, Michael Gutperle, Matthew Headrick, Shiraz Minwalla

We study IIA/B string theory compactified on twisted circles. These models possess closed string tachyons and reduce to type 0B/A theory in a special limit. Using methods of gauged linear sigma models and mirror symmetry we construct a conformal field theory which interpolates between these models and flat space via an auxiliary Liouville direction. Interpre

Kin-ya Oda, Nobuchika Okada

In string theory, it is well known that any hard scattering amplitude inevitably suffers exponential suppression. We demonstrate that, if the string scale is M_s < 2TeV, this intrinsically stringy behavior leads to a dramatic reduction in the QCD jet production rate with very high transverse momenta p_T > 2TeV at LHC. This suppression is sufficient to be obs

Krzysztof Belczynski, Vassiliki Kalogera, Tomasz Bulik

A new generation of ground-based interferometric detectors for gravitational waves is currently under construction or has entered the commissioning phase (LIGO, VIRGO, GEO600, TAMA). We study the most promising candidate sources for these detectors: inspiraling double compact objects. We use population synthesis methods to calculate the properties and coales

G. S. Agarwal, J. von Zanthier, C. Skornia, H. Walther

The different behaviour of first order interferences and second order correlations are investigated for the case of two coherently excited atoms. For intensity measurements this problem is equivalent to Young&#39;s double slit experiment and was investigated in an experiment by Eichmann et al. [Phys. Rev. Lett. 70, 2359 (1993)] and later analyzed in detail b

Rajendra Bhandari

The physical reality and observability of 2nπBerry phases, as opposed to the usually considered modulo 2πtopological phases is demonstrated with the help of computer simulation of a model adiabatic evolution whose parameters are varied along a closed loop in the parameter space. Using the analogy of Berry&#39;s phase with the Dirac monopole, it is concluded

Gongfa Liu, Jingyi Li, Weimin Li, Chuan Li

The injection control system of Hefei Light Source (HLS) storage ring is a subsystem of the upgraded HLS control system, which is based upon EPICS. Three programmable logic controllers (PLCs) are used as device controllers, which control one septum modulator and four kicker modulators of HLS storage ring. An Industrial PC is used as Input/Output Controller (

Jingyi Li, Gongfa Liu, Weimin Li, Chuan Li

HLS (Hefei Light Source) is a second generation synchrotron radiation source. After injected into the storage ring at energy of 200MeV, the electrons will be ramped to 800MeV. During ramping, the magnetic fields of the bend, quadruple and sextuple magnets are ramped up synchronously to keep the working point of the storage ring unchanged. This process is car

Calvin W. Johnson, Jameel-Un Nabi, W. Erich Ormand

Recently we proposed a formalism, based in nuclear statistical spectroscopy, for efficient computation of nuclear level density, or densities of states, through a sum of partitioned binomial functions (SUPARB). In this Letter we extend the formalism to the calculation of locally averaged expectation values, with specific application to spin-cutoff factors an

Jameel-Un Nabi, Calvin W. Johnson, W. Erich Ormand

Nucleosynthesis calculations require nuclear level densities for hundreds or even thousands of nuclides. Ideally one would like to constrain these level densities by microscopically motivated yet computationally cheap models. A statistical approach suggests that low moments of the Hamiltonian might be sufficient. Recently Zuker proposed a simple combinatoric

B. K. Agrawal, Tapas Sil, S. K. Samaddar, J. N. De

The relativistic mean field theory is applied to study some exotic properties of neutron rich nuclei as recently observed, namely, extension of the drip-line for $F$ nuclei from $^{29}F$ to $^{31}F$ and the appearence of a new shell closure at neutron number N=16. We find $^{31}F$ to be bound against one-neutron dripping but unbound only marginally for two n

K. I. Morozov, A. Engel, A. V. Lebedev

Floating drops of magnetic fluid can be brought into rotation by applying a rotating magnetic field. We report theoretical and experimental results on the transition from a spheroid equilibrium shape to non-axissymmetrical three-axes ellipsoids at certain values of the external field strength. The transitions are continuous for small values of the magnetic s

L. Sorriso-Valvo, V. Carbone, A. Noullez, H. Politano

A signed measure analysis of two-dimensional intermittent magnetohydrodynamic turbulence is presented. This kind of analysis is performed to characterize the scaling behavior of the sign-oscillating flow structures, and their geometrical properties. In particular, it is observed that cancellations between positive and negative contributions of the field insi

S. Murugesh, Radha Balakrishnan

We apply our recent formalism establishing new connections between the geometry of moving space curves and soliton equations, to the nonlinear Schrödinger equation (NLS). We show that any given solution of the NLS gets associated with three distinct space curve evolutions. The tangent vector of the first of these curves, the binormal vector of the second and

Richard Melrose, Jared Wunsch

For the wave equation associated to the Laplacian on a compact manifold with boundary with a conic metric (with respect to which the boundary is metrically a point) the propagation of singularities through the boundary is analyzed. Under appropriate regularity assumptions the diffracted, non-direct, wave produced by the boundary is shown to have Sobolev regu

Carlos A. Berenstein, Alekos Vidras, Alain Yger

We present a restricted version of some affine Jacobi&#39;s residue formula (on an affine algebraic variety) with applications to higher dimensional (and affine) analogues of Wood&#39;s (or Reiss&#39;s) relations about the interpolation of pieces of analytic manifolds. We also compare algebraic and analytic constructions of residue currents along analytic cy

Edward Bierstone

Let g denote a real analytic function on an open subset U of Euclidean space, and let S denote the boundary points of U where g does not admit a local analytic extension. We show that if g is semialgebraic (respectively, globally subanalytic), then S is semialgebraic (respectively, subanalytic) and g extends to a neighbourhood of cl(U)§as an analytic functio

G. Lusztig

Let G(K) be the group of K-rational points of a connected adjoint simple algebraic group defined over a non-archimedean local field K. In this paper we classify the unipotent representations of G(K) in terms of the geometry of the Langlands dual group. (This was known earlier in the special case where G(K) is an inner form of a split group.) We also determin

Tibra Ali

We compactify M-theory on seven-manifolds with a warp-factor and G-fluxes on the internal space. Because of non-zero G-fluxes, we are forced to adopt a Majorana supersymmetry spinor ansatz which does not have the usual direct product structure of two lower dimensional Majorana spinors. For the spinor ansatz that we choose, we find that supersymmetry puts str

M. A. Grebeniuk, V. D. Ivashchuk, S. -W. Kim

Black p-brane solutions for a wide class of intersection rules and Ricci-flat ``internal&#39;&#39; spaces are considered. They are defined up to moduli functions H_s obeying non-linear differential equations with certain boundary conditions imposed. A new solution with intersections corresponding to the Lie algebra C_2 is obtained. The functions H_1 and H_2

Massimo Giovannini

A manifestly gauge-invariant theory of gravitational fluctuations of brane-world scenarios is discussed. Without resorting to any specific gauge choice, a general method is presented in order to disentangle the fluctuations of the brane energy-momentum from the fluctuations of the metric. As an application of the formalism, the localization of metric fluctua

Nicolas Boulanger

We report yes-go and no-go results on consistent cross-couplings for a collection of gravitons. Motivated by the search of theories where multiplets of massless spin-two fields cross-interact, we look for all the consistent deformations of a positive sum of Pauli-Fierz actions. We also investigate the problem of deforming a (positive and negative) sum of lin

Xavier Bekaert, Sorin Cucu

We briefly review the basics of electric-magnetic duality symmetry and their geometric interpretation in the M-theory context. Then we recall some no-go theorems that prevent a simple extension of the duality symmetry to non-Abelian gauge theories.

Miloslav Znojil, Geza Levai

In many PT symmetric models with real spectra, apparently, energy levels &#34;merge and disappear&#34; at a point of the spontaneous PT-symmetry breaking. We argue that such an oversimplified and discontinuous physical interpretation of this mechanism as proposed, e.g., by one of us in Phys. Lett. A 285 (2001), p. 7 would be inappropriate. Using the elementa

Soon-Tae Hong, Bum-Hoon Lee, Young-Jai Park

We reconsider the $CP^{1}$ model with the Hopf term by using the Batalin-Fradkin-Tyutin (BFT) scheme, which is an improved version of the Dirac quantization method. We also perform a semi-classical quantization of the topological charge Q sector by exploiting the collective coordinates to explicitly show the fractional spin statistics.

D. Kharzeev, E. Levin, M. Nardi

The experimental results on hadron production obtained recently at RHIC offer a new prospective on the energy dependence of the nuclear collision dynamics. In particular, it is possible that parton saturation -- the phenomenon likely providing initial conditions for the multi--particle production at RHIC energies -- may have started to set in central heavy i

U. Baur, R. Clare, J. Erler, S. Heinemeyer

The impact of theoretical and experimental uncertainties on the indirect determination of the Higgs boson mass, MH, in the Standard Model (SM) is discussed. Special emphasis is put on the electroweak precision observables MW (the W boson mass) and sin^2(theta_eff) (the effective leptonic mixing angle). The current uncertainties of the theoretical predictions

V. Drollinger, T. Muller, D. Denegri

Search for the Higgs Boson is one of the prime goals of the LHC. Higgs bosons lighter than 130 GeV decay mainly to a b-quark pair. While the detection of a directly produced Higgs boson in the bb channel is impossible because of the huge QCD background, the channel ttH -> lnqqbbbb is very promising in the Standard Model and the MSSM. We discuss an event reco

Jean Alexandre, Nick E. Mavromatos

We discuss one-loop radiatively-induced magnetic moment in four-dimensional quantum electrodynamics (QED) with anisotropic coupling, and examine various cases which may be of interest in effective gauge theories of antiferromagnets, whose planar limit coresponds to highly anisotropic QED couplings. We find a different scaling with the magnetic field intensit

Wolfgang Ochs

We discuss the classification of the light scalar mesons with mass below 2 GeV into q qbar nonets and glueballs. The information on production and decay of these states, in particular recent information on f_0(980), f_0(400-1200) (or sigma(600)) and f_0(1500) is considered. Although the data are not yet very precise the recent information is in favour of the

M. Battaglia, A. De Roeck

The perspectives for the observation of the rare decay H -> mumu decay and the determination of the muon Yukawa coupling at a TeV-class and at a multi-TeV e+e- linear colliders are discussed. The signal for the decay can be obtained at 0.8 TeV and a first estimate of the coupling derived. A linear collider operating at 3 TeV, with high luminosity, is able to

J. Bartels, M. G. Ryskin

The small-x behavior of the singlet contributions to the polarized structure function g_2(x,Q^2) is calculated in the double-logarithmic approximation of perturbative QCD. The dominant contribution is due to the gluons which, in contrast to the unpolarized case, mix with the fermions also in the small-x domain. We find a power-like growth in 1/x in the odd-s

N. O. Agasian, S. M. Fedorov

The influence of nonperturbative fields on instantons in quantum chromodynamics is studied. Effective action for instanton is derived in bilocal approximation and it is demonstrated that stochastic background gluon fields are responsible for IR stabilization of instantons. It is shown that instanton size in QCD is of order of 0.25 fm. Comparison of obtained

Hans Peter Nilles, Marco Peloso

The success of primordial nucleosynthesis imposes stringent bounds on the abundance of gravitational relics. This is particularly true for gravitinos, which - for models with gravitationally mediated supersymmetry breaking - are expected to have a mass below the TeV scale and thus to decay only after nucleosynthesis has concluded. We discuss the nonthermal p

H. Eberl, M. Kincel, W. Majerotto, Y. Yamada

We present the one-loop corrected decay widths for the decays of the neutral Higgs bosons h^0, H^0, and A^0 into a neutralino pair neu_m neu_n (m, n = 1, >..., 4) and to the decay neu_m -> (h^0, H^0, A^0) + neu_n. The corrections contain the one-loop contributions of all fermions and sfermions. All parameters are taken on-shell. This requires a proper treatm

A. Leike

Werner Heisenberg&#39;s work is the foundation for many topics of present research. This is also true for the search for extra gauge bosons. The prospects of future colliders in this search are shortly mentioned.

Rouzbeh Allahverdi, Kari Enqvist, Anupam Mazumdar

We consider heavy stable neutral particles in the context of supergravity and show that a gravitationally suppressed inflaton decay can produce such particles in cosmologically interesting abundances within a wide mass range $10^3 {\rm GeV} \leq m_X \leq 10^{11} {\rm GeV}$. In gravity-mediated supersymmetry breaking models, a heavy particle can decay into it

Chongxing Yue, Yuanben Dai, Qingjun Xu, Guoli Liu

We consider the flavor changing neutral current(FCNC) process $e^{+}e^{-}\to\bar{t}c$(or $t\bar{c}$) in the context of topcolor-assisted technicolor(TC2) models. We find that the contributions of charged scalars (technipions and top-pions) and topcolor gauge bosons are negligibly small. The neutral scalars (top-pion $π_{t}^{0}$ and top-Higgs $h_{t}^{0}$) can

Michele Della Morte, Roberto Frezzotti, Jochen Heitger

Non-perturbative lattice studies of QCD in the chiral thermodynamic regime, where chiral symmetry is spontaneously broken, require to deal with almost quark zero modes in a theoretically clean and computationally efficient way. We discuss the basic features and some realistic tests of a formulation, known as lattice tmQCD, that fulfills these requirements. B

P. Dimopoulos, K. Farakos, G. Koutsoumbas

We explore, by Monte Carlo and Mean Field methods, the five--dimensional SU(2) adjoint Higgs model. We allow for the possibility of different couplings along one direction, describing the so--called anisotropic model. This study is motivated by the possibility of the appearance of four--dimensional layered dynamics. Actually, our results lead to the conclusi

Apoorva Patel

Mesons in large-N QCD are analysed in light-front coordinates with a transverse lattice at strong coupling. In this limit, their properties can be expressed as simple renormalisations of the &#39;t Hooft model results. The integral eigenvalue equation for the mesons is derived. Spectrum, lightcone wavefunctions and form factors of various mesons can be numer

John A. L. McIntosh, Lloyd C. L. Hollenberg

An analytic calculation of the photon mass gap M of compact U(1)_{2+1} in the Hamiltonian formalism is performed utilizing the first four Hamiltonian moments with respect to a one-plaquette mean field state in the plaquette expansion method. Scaling of M is clearly evident at and beyond the transition from strong to weak coupling. The scaling behaviour agree

M. Danilov, Yu. Gilitsky, T. Kvaratschellia, L. Laptin

Experimental conditions at the HERA-B experiment impose very strong requirements for gaseous detectors. The charged particle fluxes through the HERA-B tracking system, varying with the radial distance $R$ from the beam line, are about $2 \times 10^{7}/R^{2}$ particles per second, and comparable to those that will be encountered by LHC experiments. The severe

M. Danilov, Yu. Gilitsky, T. Kvaratschellia, L. Laptin

Experimental conditions at the HERA-B experiment impose very strong requirements for gaseous detectors. The charged particle fluxes through the HERA-B tracking system, varying with the radial distance R from the beam line, are about $2 \times 10^{7}/R^{2}$ particles per second, and comparable to those that will be encountered by LHC experiments. The severe r

D. Yu. Bolkhovityanov, R. G. Gromov, E. A. Gousev, K. V. Gubin

This report concerns the present status of VEPP-5 control system. The control system hardware consists of CAMAC blocks, a set of crate controllers based on INMOS transputers and ICL-1900 architecture processor Odrenok, and Pentium-based workstations. For small tasks simple serial CAMAC controllers are used. For slow controls of power supplies the CANBUS is b

S. Cebrian, J. Amare, J. M. Carmona, E. Garcia

ANAIS (Annual Modulation with NaI&#39;s) is an experiment planned to investigate seasonal modulation effects in the signal of galactic WIMPs using up to 107 kg of NaI(Tl) in the Canfranc Underground Laboratory (Spain). A prototype using one single crystal (10.7 kg) is being developed before the installation of the complete experiment; the first results prese

Carmine Pagliarone

If nature realizes $TeV$ scale gravity, we are entering a very exciting period in which we could be able to address, experimentally, some questions on quantum gravity, strings, branes and other exotic aspects of the fundamental theory of gravity. This article reviews recent development in models with Large Extra Dimensions and Black hole production at future

Kristian Kersting, Luc De Raedt

Bayesian networks provide an elegant formalism for representing and reasoning about uncertainty using probability theory. Theyare a probabilistic extension of propositional logic and, hence, inherit some of the limitations of propositional logic, such as the difficulties to represent objects and relations. We introduce a generalization of Bayesian networks,

Michel Rigo

Let U be a numeration system, a set X of integers is U-star-free if the set made up of the U-representations of the elements in X is a star-free regular language. Answering a question of A. de Luca and A. Restivo, we obtain a complete logical characterization of the U-star-free sets of integers for suitable numeration systems related to a Pisot number and in

Jeff Z. Y. Chen

A double stranded DNA molecule under the stress of a pulling force acting on the strand terminals exhibits a partially denatured structure or can be completely unzipped depending the magnitude of the pulling force. A scaling argument for relationships amongst basic length scales is presented that takes into account the heterogeneity of the sequence. The resu

M. V. Fistul, A. E. Miroshnichenko, S. Flach, M. Schuster

We present theoretical and experimental studies of resonant localized resistive states in a Josephson junction ladder. These complex breather states are obtained by tuning the breather frequency into the upper band of linear electromagnetic oscillations of the ladder. Their prominent feature is the appearance of resonant steps in the current-voltage (I-V) ch

Y. Gu, K. W. Yu

We investigate the linear and nonlinear optical responses of dilute anisotropic networks using the Green&#39;s-function formalism (GFF)[Gu Y et al. 1999 Phys. Rev. B 59 12847]. For the different applied fields, numerical calculations indicate that a large third order nonlinear enhancement and a broad infrared absorption arise from the geometric anisotropy. I

Vittoria Colizza, Alain Barrat, Vittorio Loreto

In this Letter we report the measurement of a pseudo-temperature for compacting granular media on the basis of the Fluctuation-Dissipation relations in the aging dynamics of a model system. From the violation of the Fluctuation-Dissipation Theorem an effective temperature emerges (a dynamical temperature T_{dyn}) whose ratio with the equilibrium temperature

F. Chevy, V. Bretin, P. Rosenbusch, K. W. Madison

We study experimentally the transverse monopole mode of an elongated rubidium condensate. Due to the scaling invariance of the non-linear Schrödinger (Gross-Pitaevski) equation, the oscillation is monochromatic and sinusoidal at short times, even under strong excitation. For ultra-low temperatures, the quality factor $Q=ω_0/γ_0$ can exceed 2000, where $ω_0$

Renat Yulmetyev, Fail Gafarov, Peter Hänggi, Raoul Nigmatullin

The basic purpose of the paper is to draw the attention of researchers to new possibilities of differentiation of similar signals having different nature. One of examples of such kind of signals is presented by seismograms containing recordings of earthquakes (EQ&#39;s) and technogenic explosions (TE&#39;s). We propose here a discrete stochastic model for po

I. Varga, C. Schlichenmaier, T. Meier, K. Maschke

The dynamics of optically generated electron-hole pairs is investigated in a disordered semiconductor nanowire. The particle pairs are generated by short laser pulses and their dynamics is followed using the Heisenberg equation of motion. Is is shown that Coulomb-correlation acts against localization in the case of the two-interacting particles (TIP) problem

R. R. Bacsa, A. Peigney, Ch. Laurent, P. Puech

We have assigned the chirality of the internal tubes of double walled carbon nanotubes grown by catalytic chemical vapor deposition using the high sensitivity of the radial breathing mode (RB) in inelastic light scattering experiments. The deduced chirality corresponds to several semiconducting and only two metallic internal tubes. The RB modes are systemati

E. Schachinger, J. P. Carbotte

The fluctuation spectrum responsible for the inelastic scattering in YBa$_2$Cu$_3$O$_{6.99}$ which was recently determined from consideration of the in-plane optical conductivity in the infrared, is used to calculate the temperature dependence of the microwave conductivity at several measured frequencies. Reasonable overall agreement can only be achieved if,

Zhijian Li, J. Q. Liang, F. -C. Pu

We investigate a polyacetylene ring in an axially symmetric, static electric field with a modified SSH Hamiltonian of a polyacetylene chain. An effective gauge potential of the single electron Hamiltonian due to spin-field interaction is obtained and it results in a Fröhlich&#39;s type of superconductivity equivalent to the effect of travelling lattice wave.

H. P. Yang, H. H. Wen, Z. W. Zhao, S. L. Li

Sulfur intercalated graphite composites with diamagnetic transitions at 6.7 K and 37 K are prepared. The magnetization hysteresis loops (MHL), Xray diffraction patterns, and resistance were measured. From the MHL, a slight superconducting like penetration process is observed at 15 K in low field region. The XRD shows no big difference from the mixture of gra

MJ Davis, CW Gardiner

We extend the earlier model of condensate growth of Davis et al [Davis MJ, Gardiner CW and Ballagh RJ 2000, Phys. Rev. A 62, 063608] to include the effect of gravity in a magnetic trap. We carry out calculations to model the experiment reported by Köhl et al [Köhl M, Davis MJ, Gardiner CW, Hänsch T and Esslinger T, Preprint, cond-mat/0106642] who study the f

Subir Sachdev

We review the theories of a few quantum phase transitions in two-dimensional correlated electron systems and discuss their application to the cuprate high temperature superconductors. The coupled-ladder antiferromagnet displays a transition between the Neel state and a spin gap paramagnet with a sharp S=1 exciton: we develop a careful argument which eventual

Kevin A. Pimbblet, Ian Smail, Tadayuki Kodama, Warrick J. Couch

(Abridged) We present a photometric investigation of the variation in galaxy colour with environment in 11 X-ray luminous clusters at 0.07<z<0.16 taken from the Las Campanas/AAT Rich Cluster Survey. We study the properties of the galaxy populations in individual clusters and take advantage of the homogeneity of the sample to combine the clusters together to

V. A. Kudryavtsev

Production of muon pairs by high-energy photons in electromagnetic and hadronic showers in atmosphere has been calculated. The effect of muon pair production in hadronic Extensive Air Showers (EAS) is unlikely to be seen by next generation detectors. Applications of muon pair production process in electromagnetic showers to the very high energy gamma-ray ast

S. Eisenbart, K. Beuermann, K. Reinsch, B. T. Gaensicke

We present phase-resolved infrared and optical spectrophotometry of the intermediate polar EX Hya supplemented by archival ultraviolet data. The spin-modulated emission from the accretion funnel and the emission from the accretion disk or ring contain substantial optically thin components. The white dwarf dominates the unmodulated flux in the ultraviolet and

David Teyssier, Patrick Hennebelle, Michel Perault

This paper presents follow-up observations of the mid-Infrared dark clouds selected from the ISOGAL inner Galaxy sample. On-the-fly maps of 13CO, C18O and the 1.2 mm continuum emission have been obtained a the IRAM 30-m telescope. A preliminary analysis of the physico-chemical conditions at works in the clouds is given and molecular depletion onto cold grain

A. D. Schwope, V. Hambaryan, R. Schwarz

We present an analysis of the X-ray light curves of the magnetic cataclysmic variable DP Leo using recently performed XMM-Newton EPIC and archival ROSAT PSPC observations. We determine the eclipse length at X-ray wavelengths to be 235 +-5 s, slightly longer than at ultra-violet wavelengths, where it lasts 225s. The implied inclination and mass ratio for an a

S. Ettori

Recent analyses of XMM and Chandra data of the cores of X-ray bright clusters of galaxies show that modeling with a multi-phase gas in which several temperatures and densities are in equilibrium might not be appropriate. Instead, a single-phase model seems able to reproduce properly the spectra collected in annuli from the central region. The measured single

Boris Dintrans, Michel Rieutord

We present numerical simulations of gravito-inertial waves propagating in radiative zones of rapidly rotating stars. A first model, using the Boussinesq approximation, allows us to study the oscillations of a quasi-incompressible stratified fluid embedded in a rapidly rotating sphere or spherical shell. In a second step, we investigate the case of a Gamma-Do

Robert Coquereaux, Alex Grossmann

In view of new experimental results that strongly suggest a non-zero cosmological constant, it becomes interesting to revisit the Friedman-Lemaitre model of evolution of a universe with cosmological constant and radiation pressure. In this paper, we discuss the explicit solutions for that model and perform numerical explorations for reasonable values of cosm

Eric Braaten, Yu Jia, Thomas Mehen

The asymmetries between charm and anticharm mesons observed in fixed-target photoproduction experiments are an order of magnitude larger than the asymmetries predicted by conventional perturbative QCD. We show that these charm meson asymmetries can be explained by a heavy-quark recombination mechanism for heavy meson production. In this process, a charm quar

A. de la Macorra

We show that the condensates of a non-abelian gauge group, unified with the standard model gauge groups, can parameterize the present day cosmological constant and play the role of quintessence. The models agree with SN1a and recent CMB analysis. These models have {\it no free} parameters. Even the initial energy density at the unification scale and at the c

I. Ya. Aref&#39;eva, D. M. Belov, A. A. Giryavets, A. S. Koshelev

In this lecture notes we explain and discuss some ideas concerning noncommutative geometry in general, as well as noncommutative field theories and string field theories. We consider noncommutative quantum field theories emphasizing an issue of their renormalizability and the UV/IR mixing. Sen&#39;s conjectures on open string tachyon condensation and their a

Probir Roy, Sudhir K. Vempati

The three neutrino Zee model and its extension including three active and one sterile species are studied in the light of new neutrino oscillation data. We obtain analytical relations for the mixing angle in solar oscillations in terms of neutrino mass squared differences. For the four neutrino case, we obtain the result $\mathsf{sin^2 2 θ_\odot \approx 1 -

I. Antoniadis, K. Benakli, A. Laugier

We study a class of type I string models with supersymmetry broken on the world-volume of some D-branes and vanishing tree-level potential. Despite the non-supersymmetric spectrum, supersymmetry is non-linearly realized on these D-branes, while it is spontaneously broken in the bulk by Scherk-Schwarz boundary conditions. These models can easily accommodate 3

Giacomo Cacciapaglia, Marco Cirelli, Giampaolo Cristadoro

In the framework of a recently proposed extension of the Standard Model, with N=1 SuperSymmetry in 5 dimensions, compactified on R^1/(Z_2 x Z&#39;_2), we compute the muon anomalous magnetic moment at one loop to order (M_W R)^2, where R is the compactification radius. We find the corrections to be small with respect to the SM pure weak contribution and not c

Giacomo Cacciapaglia, Marco Cirelli, Giampaolo Cristadoro

In an extension of the Standard Model with one extra dimension and N=1 supersymmetry compactified on R^1/(Z_2 x Z&#39;_2), we compute the Higgs boson decay width into two gluons, relevant to Higgs production in hadronic collisions. At one loop, the decay width is significantly suppressed with respect to the SM. For a compactification radius 1/R = 370 \pm 70

Diego A. Wisniacki, Eduardo Vergini, Horacio M. Pastawski, Fernando M. Cucchietti

The Loschmidt echo (LE) measures the ability of a system to return to the initial state after a forward quantum evolution followed by a backward perturbed one. It has been conjectured that the echo of a classically chaotic system decays exponentially, with a decay rate given by the minimum between the width $Γ$ of the local density of states and the Lyapunov

F. Franke, S. Hesselbach

Neutralinos with a large singlino component may appear in extended supersymmetric models with additional singlet Higgs fields. Since singlinos do not couple to (s)fermions and gauge bosons, the cross sections for the production of singlino dominated neutralinos are generally small. Within the framework of the Next-to-Minimal Supersymmetric Standard Model (NM

V. Baran, M. Colonna, M. Di Toro, V. Greco

We investigate properties of the symmetry term in the equation-of-state (EOS) of nuclear matter (NM) from the analysis of simulations of fragmentation events in intermediate energy heavy ion collisions. For charge asymmetric systems a qualitative new feature in the liquid-gas phase transition is predicted: the onset of chemical instabilities with a mixture o

U. D. Jentschura, G. Soff, P. J. Indelicato

We describe a simplified derivation for the relativistic corrections of order $α^4$ for a bound system consisting of two spinless particles. We devote special attention to pionium, the bound system of two oppositely charged pions. The leading quantum electrodynamic (QED) correction to the energy levels is of the order of $α^3$ and due to electronic vacuum po

S. A. Pavluchenko, N. Yu. Savchenko, A. V. Toporensky

The generality of inflation in closed FRW Universe is studied for the models with a scalar field on a brane and with a complex scalar field. The results obtained are compared with the previously known results for the model with a scalar field and a perfect fluid. The influence of the measure chosen in the initial condition space on the ratio of inflationary

J. Alcaraz

We discuss differences between on-shell and off-shell treatments in the search for anomalous neutral triple gauge couplings in $\mathrm{e^+ e^-}$ collisions. We find that the usual on-shell framework represents an optimal starting point, covering all scenarios in which a reasonable experimental sensitivity is expected. We show that off-shell effects lead to

Antonio Campos

We have investigated the effects of a generic bulk first-order phase transition on thick Minkowski branes in warped geometries. As occurs in Euclidean space, when the system is brought near the phase transition an interface separating two ordered phases splits into two interfaces with a disordered phase in between. A remarkable and distinctive feature is tha

Levon Pogosian

There are $N-1$ classes of kink solutions in $SU(N)\times Z_2$. We show how interactions between various kinks depend on the classes of individual kinks as well as on their orientations with respect to each other in the internal space. In particular, we find that the attractive or repulsive nature of the interaction depends on the trace of the product of cha

R. Benton Metcalf, HongSheng Zhao

We demonstrate that the flux ratios of 4-image lensed quasars provide a powerful means of probing the small scale structure of Dark Matter (DM) halos. A family of smooth lens models can precisely predict certain combinations of flux ratios using only the positions of the images and lens as inputs. Using 5 observed lens systems we show that real galaxies {\it

V. D. P. Servedio, S. -L. Drechsler, T. Mishonov

We report layer-Korringa-Kohn-Rostocker calculations for bulk and surface states as well as the corresponding angle resolved photoemission (ARPES) intensities of MgB2. Our theoretical results reproduce very well the recent ARPES data by Uchiyama et al., cond-mat/0111152. At least two surface states are assigned. Consequences of SFS on the anisotropy of the u

R. Iengo, R. Ramachandran

We formulate the Landau problem in the context of the noncommutative analog of a surface of constant negative curvature, that is $AdS_2$ surface, and obtain the spectrum and contrast the same with the Landau levels one finds in the case of the commutative $AdS_2$ space.

Chao-Shang Huang, Shou-hua Zhu

The polarizations of the heavy quark ($q=t$ or $b$) in the process $e^+e^- \to q \bar q h$ have been calculated in the general two Higgs doublet model. The CP violating normal polarization of the top quark can reach 8%, and $2 \sim 3%$ for the bottom quark, while it is zero in the standard model. The longitudinal and transverse polarizations of the bottom qu

Belle Collaboration, K. Abe

Using a sample of $31.3 x 10^6 $B\bar{B}$ pairs collected with the Belle detector at the Y(4S) resonance, we make the first observation of the charged B meson decay to chi_c0 and a charged kaon. The measured branching fraction is Br(B+ -> chi_c0 K+)=(6.0^{+2.1}_{-1.8}\pm1.1)x10^{-4}, where the first error is statistical, and the second is systematic.

G. Savvidy, R. Manvelyan

We study quantum corrections in the earlier proposed string theory, which is based on Weyl invariant purely extrinsic curvature action. At one-loop level it remains Weyl invariant irrespective of the dimension D of the embedding spacetime. To some extent the counterterms are reminiscent of the ones in pure quantum gravity. At classical level the string tensi

Miao Li, Feng-Li Lin

We propose a new holographic C-function for the accelerating universe defined in the stringy frame motivated mainly by the fact that the number of degrees of freedom should be infinite for a physical system of infinite size. This is the generalization of Strominger&#39;s recent proposal of the holographic C-function to the asymptotically non-de Sitter univer

E. S. Pisanova, N. B. Ivanov, N. S. Tonchev

Within Takahashi&#39;s spin-wave theory we study finite size and temperature effects near the quantum critical point in the $J_{1}-J_{2}$ Heisenberg antiferromagnet defined on a strip ($L\times\infty$). In the continuum limit, the theory predicts universal finite size and temperature corrections and describes the dimensional crossover in magnetic properties

Marco Battaglia, Eduard Boos, Weiming Yao

The determination of the shape of the Higgs potential is needed to complete the investigation of the Higgs profile and to obtain a direct experimental proof of the mechanism of electro-weak symmetry breaking. This can be achieved, at a linear collider, by determining the Higgs triple self-coupling g_HHH in the processes e+e--> HHZ and HHnunu and, possibly, t

Yoji Michishita, Piljin Yi

We consider a D-brane probe in unstable string background associated with flux branes. The twist in spacetime metric reponsible for the supersymmetry breaking is shown to manifest itself in mixing of open Wilson lines with the phases of some adjoint matter fields, resulting in a nonlocal and nonsupersymmetric form of Yang-Mills theory as the probe dynamics.

C. M. Zhang

Based on the interpretation of the twin kilohertz Quasi Periodic Oscillations (kHz QPOs) of X-ray spectra of Low Mass X-Ray Binaries (LMXBs) to the Keplerian and the periastron precession frequencies at the magnetosphere-disk of X-ray neutron star (NS) respectively, we ascribe the low frequency Quasi Periodic Oscillations (LFQPO) and HBO (15-60 Hz QPO for Z

Hiroaki Kanno, Yukinori Yasui

We continue the investigation of Spin(7) holonomy metric of cohomogeneity one with the principal orbit SU(3)/U(1). A special choice of U(1) embedding in SU(3) allows more general metric ansatz with five metric functions. There are two possible singular orbits in the first order system of Spin(7) instanton equation. One is the flag manifold $SU(3)/T^2$ also k

G. V. M. Williams, R. Dupree, A. Howes, S. Kramer

We report the results from a thermopower and a Cu nuclear magnetic resonance (NMR) study of the infinite CuO2 layer electron doped high temperature superconducting cuprate (HTSC), Sr0.9La0.1CuO2. We find that the temperature dependence of the thermopower, S(T), is different from that observed in the hole doped HTSC. In particular, we find that dS(T)/dT is po