January 2004 arXiv papers — page 6

M. V. Chizhov

The inserting of antisymmetric tensor fields into the standard electroweak theory may explain the recent experiments on pi -> e nu gamma and K -> pi e nu decays. New intermediate particles can induce the destructive interference in the pion decay and the nonzero tensor and scalar form factors in the kaon decay.

S. Munier, R. Peschanski

Using non-trivial mathematical properties of a class of nonlinear evolution equations, we obtain the universal terms in the asymptotic expansion in rapidity of the saturation scale and of the unintegrated gluon density from the Balitsky-Kovchegov equation. These terms are independent of the initial conditions and of the details of the equation. The last suba

Chongxing Yue, Wei Wang

In the context of the littlest Higgs(LH) model, we study the contributions of the new particles to the branching ratio $R_{b}$. We find that the contributions mainly dependent on the free parameters $f$, $c'$ and $x_{L}$. The precision measurement value of $R_{b}$ gives severe constraints on these free parameters.

H. -J. He, Y. -P. Kuang, C. -P. Yuan, B. Zhang

We propose a sensitive way to test the anomalous HVV couplings (V=W^\pm, Z^0) of the Higgs boson (H), which can arise from either the dimension-3 effective operator in a nonlinearly realized Higgs sector or the dimension-6 effective operators in a linearly realized Higgs sector, via studying the VV scattering processes at the CERN Large Hadron Collider (LHC)

Alfredo T. Suzuki, Alexandre G. M. Schmidt

We present calculations for non-planar double-box with four massless/massive external/internal legs/propagators. The results are expressed for arbitrary exponents of propagators and dimension in terms of Lauricella's hypergeometric functions of three variables and hypergeometric-like multiple series.

K. Jimmy Juge, J. Kuti, C. Morningstar

Three distinct scales are identified in the excitation spectrum of the gluon field around a static quark-antiquark pair as the color source separation R is varied. The spectrum, with string-like excitations on the largest length scales of 2-3 fm, provides clues in its rich fine structure for developing an effective bosonic string description. New results are

P. Kramer, M. Lorente

Spin networks are graphs derived from 3nj symbols of angular momentum. The surface embedding, the topology and dualization of these networks are considered. Embeddings into compact surfaces include the orientable sphere S^2 and the torus T, and the not orientable projective space P^2 and Klein's bottle K. Two families of 3nj graphs admit embeddings of mi

E. M. O'Shea

Gravitational waves in isotropic cosmologies were recently studied using the gauge-invariant approach of Ellis-Bruni. We now construct the linearised metric perturbations of the background Robertson-Walker space-time which reproduce the results obtained in that study. The analysis carried out here also facilitates an easy comparison with Bardeen.

H. W. Peng

Taking a hint from Dirac's large number hypothesis, we note the existence of cosmic combined conservation laws that work to cosmologically long time. We thus modify or generalize Einstein's theory of general relativity with fixed gravitation constant $G$ to a theory for varying $G$, which can be applied to cosmology without inconsistency, where a ten

Markus Demleitner, Michael Kurtz, Alberto Accomazzi, Günther Eichhorn

We describe a system used by the NASA Astrophysics Data System to identify bibliographic references obtained from scanned article pages by OCR methods with records in a bibliographic database. We analyze the process generating the noisy references and conclude that the three-step procedure of correcting the OCR results, parsing the corrected string and match

Russell K. Standish, Duraid Madina

ClassdescMP is a distributed memory parallel programming system for use with C++ and MPI. It uses the Classdesc reflection system to ease the task of building complicated messages to be sent between processes. It doesn't hide the underlying MPI API, so it is an augmentation of MPI capabilities. Users can still call standard MPI function calls if needed f

Russell K. Standish, Richard Leow

\EcoLab{} is an agent based modeling system for C++ programmers, strongly influenced by the design of Swarm. This paper is just a brief outline of \EcoLab's features, more details can be found in other published articles, documentation and source code from the \EcoLab{} website.

Richard Leow, Russell K. Standish

Objective-C is still the language of choice if users want to run their simulation efficiently under the Swarm environment since the Swarm environment itself was written in Objective-C. The language is a fast, object-oriented and easy to learn. However, the language is less well known than, less expressive than, and lacks support for many important features o

Duraid Madina, Russell K. Standish

Object-oriented programming languages such as Java and Objective C have become popular for implementing agent-based and other object-based simulations since objects in those languages can {\em reflect} (i.e. make runtime queries of an object's structure). This allows, for example, a fairly trivial {\em serialisation} routine (conversion of an object into

V. B. Svetovoy

Optical properties of the deposited gold films are discussed in connection with the Casimir force prediction. Voids in the films and electron scattering on the grain boundaries reduce the force at small separations on the 2% level in comparison with the bulk material prediction. The contribution of the patch potential due to polycrystalline structure of the

G. P. Zhang

We are pleased to see that Jeckelmann has made many changes to the original version of his comment on our paper as a result of our response. Here is a copy of this powerful response that reveals problems in his previous results. However, since this response was written before his revised comment came out, new issues in his new comment, which will be commente

J. Hegedus, K Kohary, S. Kugler, K. Shimakawa

Tight-binding molecular dynamics simulations of photo-excitations in small Se clusters (isolated Se$_8$ ring and helical Se chain) and glassy Se networks (containing 162 atoms) were carried out in order to analyse the photo induced instability inside the amorphous selenium. In the cluster systems after taking an electron from the highest occupied molecular o

C. A. Regal, M. Greiner, D. S. Jin

We have observed condensation of fermionic atom pairs in the BCS-BEC crossover regime. A trapped gas of fermionic 40K atoms is evaporatively cooled to quantum degeneracy and then a magnetic-field Feshbach resonance is used to control the atom-atom interactions. The location of this resonance is precisely determined from low-density measurements of molecule d

Franz X. Bronold, Andreas Alvermann, Holger Fehske

Based on the statistical dynamical mean field theory, we investigate, in a generic model for a strongly coupled disordered electron-phonon system, the competition between polaron formation and Anderson localization. The statistical dynamical mean field approximation maps the lattice problem to an ensemble of self-consistently embedded impurity problems. It i

M. E. Torio, K. Hallberg, S. Flach, A. E. Miroshnichenko

We compute the zero bias conductance of electrons through a single ballistic channel weakly coupled to a side quantum dot with Coulomb interaction. In contrast to the standard setup which is designed to measure the transport through the dot, the channel conductance reveals Coulomb blockade dips rather then peaks due to the Fano-like backscattering. At zero t

Fabio D. A. Aarao Reis

We analyze simulations results of a model proposed for etching of a crystalline solid and results of other discrete models in the 2+1-dimensional Kardar-Parisi-Zhang (KPZ) class. In the steady states, the moments W_n of orders n=2,3,4 of the heights distribution are estimated. Results for the etching model, the ballistic deposition (BD) model and the tempera

A. E. Allahverdyan, Th. M. Nieuwenhuizen

The minimum work principle states that work done on a thermally isolated equilibrium system is minimal for the adiabatically slow (reversible) realization of a given process. This principle, one of the formulations of the second law, is studied here for finite (possibly large) quantum systems interacting with macroscopic sources of work. It is shown to be va

K. Hannewald, P. A. Bobbert

We present a novel theory of charge-carrier mobilities in organic molecular crystals of high purity. Our approach is based on Holstein's original concept of small-polaron bands but generalized with respect to the inclusion of nonlocal electron-phonon coupling. We derive an explicit expression for the mobilities as a function of temperature and, using ab-

Hiroki Suyari

We present the conclusive mathematical structure behind Tsallis statistics. We obtain mainly the following five theoretical results: (i) the one-to-one correspondence between the q-multinomial coefficient and Tsallis entropy, (ii) symmetry behind Tsallis statistics, (iii) the numerical computations revealing the existence of the central limit theorem in Tsal

A. Perlov, S. Chadov, H. Ebert, L. Chioncel

The influence of dynamical correlation effects on the magneto-optical properties of ferromagnetic Fe and Ni has been investigated. In addition the temperature dependence of the self-energy and its influence on the DOS and optical conductivity is considered. Magneto-optical properties were calculated on the basis of the one-particle Green's function, whic

M. E. Perel'man

From the microscopic point of view almost all bonds between particles of condensed substances must be performed by exchanges of virtual photons. Consequently the duration of their virtuality must be longer than the extent of their free path in the substance, the magnitudes of all expressions in such inequality are known from low frequencies scattering. This

S. Fantoni, R. Guardiola, J. Navarro

The diffusion Monte Carlo technique is used to calculate and analyze the excitation spectrum of a single 3He atom bound to a cluster with N 4He atoms, with the aim of establishing the most adequate filling ordering of single-fermion orbits to the mixed clusters with a large number of 3He atoms. The resulting ordering looks like the rotational spectrum of a d

Hiroki Suyari

We present the q-Stirling's formula using the q-product determined by Tsallis entropy as nonextensive generalization of the usual Stirling's formula. The numerical computations and the proof are also shown. Moreover, we derive and prove some inequalities and equalities concerning the q-Stirling's formula. Applying the q-Stirling's formula, th

V. Oudovenko, K. Haule, S. Y. Savrasov, D. Villani

A rational representation for the self-energy is explored to interpolate the solution of the Anderson impurity model in general orbitally degenerate case. Several constrains such as the Friedel's sum rule, high--frequency moments and the value of quasiparticle residue are used to establish the equations for the coefficients of the interpolation. We test

W. Gotze, M. Sperl

Nearly-logarithmic decay of correlations, which was observed for several supercooled liquids in optical-Kerr-effect experiments [G. Hinze et al. Phys. Rev. Lett. 84, 2437(2000), H. Cang et al. Phys. Rev. Lett. 90, 197401 (2003)], is explained within the mode-coupling theory for ideal glass transitions as manifestation of the $β$-peak phenomenon. A schematic

T. Erdmann, U. S. Schwarz

We solve the stochastic equations for a cluster of parallel bonds with shared constant loading, rebinding and the completely dissociated state as an absorbing boundary. In the small force regime, cluster lifetime grows only logarithmically with bond number for weak rebinding, but exponentially for strong rebinding. Therefore rebinding is essential to ensure

A. Perez-Madrid

This contribution is dedicated to dilucidating the role of the Gibbs entropy in the discussion of the emergence of irreversibility in the macroscopic world from the microscopic level. By using an extension of the Onsager theory to the phase space we obtain a generalization of the Liouville equation describing the evolution of the distribution vector in the f

D. -S. Lee, K. -I. Goh, B. Kahng, D. Kim

Avalanche dynamics is an indispensable feature of complex systems. Here we study the self-organized critical dynamics of avalanches on scale-free networks with degree exponent $γ$ through the Bak-Tang-Wiesenfeld (BTW) sandpile model. The threshold height of a node $i$ is set as $k_i^{1-η}$ with $0\leqη<1$, where $k_i$ is the degree of node $i$. Using the bra

J. E. Bunder, K. B. Efetov

We consider some properties of odd frequency triplet superconducting condensates. In order to describe fluctuations we construct a supermatrix sigma-model for the superconductor/ferromagnet or superconductor/normal-metal structures. We show that an odd frequency triplet superconductor, when in isolation or coupled to a normal metal, generally displays behavi

A. K. Aringazin

Using the random intensity of noise (RIN) approach to the one-dimensional Laval-Dubrulle-Nazarenko type model for the Lagrangian acceleration in developed turbulence [cond-mat/0305186, cond-mat/0305459] we study the probability density function and mean acceleration conditional on velocity fluctuations. The additive noise intensity and the cross correlation

Jian-Ming Tang, Michael E. Flatte&#39;

We present the spin and orbitally resolved local density of states (LDOS) for a single Mn impurity and for two nearby Mn impurities in GaAs. The GaAs host is described by a sp^3 tight-binding Hamiltonian, and the Mn impurity is described by a local p-d hybridization and on-site potential. Local spin-polarized resonances within the valence bands significantly

Czeslaw Rudowicz

Clear definitions of the operator notations and crucial notions used in the area of electron magnetic resonance (EMR) are important in order to avoid misunderstanding and incorrect results. For the benefit of a wider audience, in this Comment we attempt to clarify the confusing points, which exist in the paper in question.

J. Steinhauer, R. Ozeri, N. Katz, N. Davidson

The roton in a Bose-Einstein condensate is computed, both near and far from a Feshbach resonance. A low-density approximation is made, allowing for an analytic result. A Monte Carlo calculation shows that the roton is larger than predicted by the low-density approximation, for the upper range of densities considered here. The low-density approximation is app

K. Tatematsu, T. Umemoto, R. Kandori, Y. Sekimoto

N2H+ observations of molecular cloud cores in Taurus with the Nobeyama 45 m radio telescope are reported. We compare ``cores with young stars&#39;&#39; with ``cores without young stars&#39;&#39;. The differences in core radius, linewidth, and core mass are small. Linewidth is dominated by thermal motions in both cases. N2H+ maps show that the intensity distr

Sun Mi Chung, Jeremy J. Drake, Vinay L. Kashyap, Li Wei Lin

In a study of Chandra High Energy Transmission Grating spectra of Algol, we clearly detect Doppler shifts caused by the orbital motion of Algol B. These data provide the first definitive proof that the X-ray emission of Algol is dominated by the secondary, in concordance with expectations that Algol A (B8) is X-ray dark. The measured Doppler shifts are sligh

Robert D. Mathieu, Søren Meibom, Christopher J. Dolan

Based on a sample of 45 main-sequence solar-type spectroscopic binaries we find the tidal circularization cutoff in the open cluster NGC 188 (age 7 Gyr) to be well-defined at a period of 15.0 days. When compared to shorter tidal circularization cutoff periods in the younger clusters M67 and the Hyades, this result establishes that tidal circularization proce

Ian A. Morrison, Thomas W. Baumgarte, Stuart L. Shapiro

The merger of binary neutron stars is likely to lead to differentially rotating remnants. In this paper, we survey several cold nuclear equations of state (EOSs) and numerically construct models of differentially rotating neutron stars in general relativity. For each EOS we tabulate maximum allowed masses as a function of the degree of differential rotation.

Santiago E. Perez Bergliaffa

The effective metric is introduced by means of two examples (non-linear electromagnetism and hydrodynamics),along with applications in Astrophysics. A sketch of the generality of the effect is also given.

L. Tornatore, S. Borgani, F. Matteucci, S. Recchi

We present results from Tree+SPH simulations of a galaxy cluster, aimed at studying the metal enrichment of the intra--cluster medium (ICM). The simulation code includes a fairly advanced treatment of star formation, as well as the release of energy feedback and detailed yields from both type-II and type-Ia supernovae, also accurately accounting for the life

B. Fuchs, E. W. Mielke

Galactic dark matter is modelled by a scalar field. In particular, it is shown that an analytically solvable toy model with a non-linear self-interaction potential U(Phi) leads to dark halo models which have the form of quasi-isothermal spheres. We argue that these fit better the observed rotation curves of galaxies than the centrally cusped halos of standar

Tim J Harries, John D Monnier, Neil H Symington, Ryuichi Kurosawa

We present radiative-transfer modelling of the dusty spiral Pinwheel Nebula observed around the Wolf-Rayet/OB-star binary WR104. The models are based on the three-dimensional radiative-transfer code TORUS, modified to include an adaptive mesh that allows us to adequately resolve both the inner spiral turns (sub-AU scales) and the outer regions of the nebula

K. G. McClements, A. Thyagaraja, N. Ben Ayed, L. Fletcher

The evolution of non-potential perturbations to a current-free magnetic X-point configuration is studied, taking into account electron inertial effects as well as resistivity. Electron inertia is shown to have a negligible effect on the evolution of the system whenever the collisionless skin depth is less than the resistive scale length. Non-potential magnet

M. A. Rodriguez-Meza, Jorge L. Cervantes-Cota

A family of potential--density pairs has been found for spherical halos and bulges of galaxies in the Newtonian limit of scalar--tensor theories of gravity. The scalar field is described by a Klein--Gordon equation with a source that is coupled to the standard Poisson equation of Newtonian gravity. The net gravitational force is given by two contributions: t

C. Cappa, W. M. Goss, K. A. van der Hucht

We report the results of a survey of radio continuum emission of Galactic Wolf-Rayet stars north of declination -46 degrees. The observations were obtained at 8.46 GHz (3.6cm) using the Very Large Array (VLA), with an angular resolution of about 6 x 9 arcsec and typical rms noise of 0.04 mJy/beam. Our survey of 34 WR stars resulted in 15 definite and 5 proba

Rachel S. Somerville

Pan-chromatic galaxy surveys are providing tightening constraints on the global mass assembly history, and high-resolution imaging of large fields is telling us when and where stars were formed. How well are state-of-the-art hierarchical galaxy formation models currently doing at reproducing these observations? I present results here that suggest that hierar

L. van Zyl, P. A. Charles, S. Arribas, T. Naylor

We present integral field spectroscopy of X2127+119, the luminous X-ray binary in the globular cluster M15, obtained with INTEGRAL/WYFFOS on the William Herschel Telescope. We find that tomograms of HeII 4686 line profiles appear to be incompatible with the previously-assumed view of X2127+119, in which the binary consists of a 1.4-solar-mass neutron star an

O. Richard, S. Théado, S. Vauclair

New solar models are presented, which have been computed with the most recent physical inputs (nuclear reaction rates, equation of state, opacities, microscopic diffusion). Rotation-induced mixing has been introduced in a way which includes the feed-back effect of the $μ$-gradient induced by helium settling. A parametrization of the tachocline region below t

B. Vollmer, C. Balkowski, V. Cayatte, W. van Driel

Deep 21-cm HI line observations of the Virgo cluster spiral galaxy NGC 4569 have been obtained with the VLA in its D configuration and with the Effelsberg 100-m telescope. A low surface density arm was discovered in the west of the galaxy, whose velocity field is distinct from that of the overall disk rotation. The observed gas distribution, velocity field,

Piotr Lubinski

The methods of obtaining the average spectral shape in a low statistics regime are presented. Different approaches to averaging are extensively tested with simulated spectra, based on the ASCA responses. The issue of binning up the spectrum before fitting is discussed together with the choice of statistic used to model the spectral shape. The best results ar

N. Mauron, M. Azzopardi, K. Gigoyan, T. R. Kendall

We present the first results of a new survey for finding cool N-type carbon (C) stars in the halo of the Galaxy. Candidates were first selected in the 2MASS Second Incremental Release database with JHKs colours typical of red AGB C stars and Ks < 13, and susequently checked through slit spectroscopy. 27 new halo C stars were discovered, and a detailed study

Kei Kotake, Shoichi Yamada, Katsuhiko Sato, Kohsuke Sumiyoshi

We perform a series of two-dimensional, axisymmetric, magnetohydrodynamic simulations of the rotational collapse of a supernova core. In order to calculate the waveforms of the gravitational wave, we derive the quadrupole formula including the contributions from the electromagnetic fields. Recent stellar evolution calculations imply that the magnetic fields

C. J. Phillips, H. J. van Langevelde

The European VLBI Network (EVN) has been used to make phase referenced, wide-field (several arcminute) spectral line observations of the 6.7-GHz methanol maser emission towards W51. In the W51main region, the bulk of the methanol is offset from an UCHII region. This probably indicates the methanol emission arises at the interface of the expanding UCHII regio

P. Arras, A. Cumming, C. Thompson

We calculate the coupled thermal evolution and magnetic field decay in relativistic model neutron stars threaded by superstrong magnetic fields (B > 10^{15} G). Our main goal is to evaluate how such ``magnetars&#39;&#39; evolve with time and how field decay modifies the transitions to core superfluidity and cooling dominated by surface X-ray emission. Observ

G. Duchene, C. McCabe, A. Ghez, B. Macintosh

We present the first 3.8 micron image of the dusty ring surrounding the young binary system GG Tau, obtained with the W. M. Keck II 10m telescope&#39;s adaptive optics system. This is the longest wavelength at which the ring has been detected in scattered light so far, allowing a multi-wavelength analysis of the scattering properties of the dust grains prese

Tsvi Piran, Nir J. Shaviv

The observed orbital parameters of the recently discovered binary pulsar J0737-3039 are used to constrain the progenitor system. In particular, the small observed eccentricity and the small inferred peculiar velocity imply that during the formation of the second NS in the system, a very small mass Delta M <~ 0.15 Msun, was ejected. A progenitor more massive

Adilet Imambekov, Mikhail Lukin, Eugene Demler

We consider insulating states of spin-one bosons in optical lattices in the presence of a weak magnetic field. For the states with more than one atom per lattice site we find a series of quantum phase transitions between states with fixed magnetization and a canted nematic phase. In the presence of a global confining potential, this unusual phase diagram lea

Rajendran Raja

Maximum likelihood fits to data can be done using binned data (histograms) and unbinned data. With binned data, one gets not only the fitted parameters but also a measure of the goodness of fit. With unbinned data, currently, the fitted parameters are obtained but no measure of goodness of fit is available. This remains, to date, an unsolved problem in stati

Mark Sadgrove, Andrew Hilliard, Terry Mullins, Scott Parkins

The effect of pulse train noise on the quantum resonance peaks of the Atom Optics Kicked Rotor is investigated experimentally. Quantum resonance peaks in the late time mean energy of the atoms are found to be surprisingly robust against all levels of noise applied to the kicking amplitude, whilst even small levels of noise on the kicking period lead to their

S. Nesseris, L. Perivolaropoulos

We study the expansion history of the universe up to a redshift of z=1.75 using the 194 recently published SnIa data by Tonry et. al. and Barris et. al. In particular we find the best fit forms of several cosmological models and $H(z)$ ansatze, determine the best fit values of their parameters and rank them according to increasing value of $χ_{min}^2$ (the m

Jonathan C. Tan

We attempt to explain the properties of the Becklin-Neugebauer (BN) object as a runaway B star, as originally proposed by Plambeck et al. (1995). This is one of the best-studied bright infrared sources, located in the Orion Nebula Cluster -- an important testing ground for massive star formation theories. From radio observations of BN&#39;s proper motion, we

Christian W. Bauer, Dan Pirjol, Ira Z. Rothstein, Iain W. Stewart

Using the soft-collinear effective theory we derive the factorization theorem for the decays B-> M1 M2 with M{1,2}= pi,K, rho,K*, at leading order in Lambda/E_M and Lambda/mb. The results derived here apply even if alpha_s(E_M Lambda) is not perturbative, and we prove that the physics sensitive to the E*Lambda scale is the same in B-> M1 M2 and B-> M form fa

E. Dudas, C. Timirgaziu

It is well-known that Scherk-Schwarz compactifications in string theory have a tachyon in the closed string spectrum appearing for a critical value of a compact radius. The tachyon can be removed by an appropriate orientifold projection in type II strings, giving rise to tachyon-free compactifications. We present explicit examples of this type in various dim

Estia J. Eichten, Kenneth Lane, Chris Quigg

We explore the influence of open-charm channels on charmonium properties, and profile the 1:3D2, 1:3D3 and 2:1P1 charmonium candidates for X(3872). The favored candidates, the 1:3D2 and 1:3D3 levels, both have prominent radiative decays. The 1:3D2 might be visible in the $D^{0}\bar{D}^{*0}$ channel, while the dominant decay of the 1:3D3 state should be into

Eli Waxman

We show that the recent identification of X-ray emission from SN1998bw is naturally explained as synchrotron emission from a shock driven into the wind surrounding the progenitor by a mildly relativistic shell ejected by the supernova, the existence of which was inferred earlier from radio observations. X-ray observations imply a shell energy E~10^{49.7}erg,

Alastair Brodlie

$p$-Mechanics is a consistent physical theory which describes both classical and quantum mechanics simultaneously through the representation theory of the Heisenberg group. In this paper we describe how non-linear canonical transformations affect $p$-mechanical observables and states. Using this we show how canonical transformations change a quantum mechanic

A. Gutierrez-Rodriguez, M. A. Hernandez-Ruiz, A. Del Rio-De Santiago

Bounds on the anomalous magnetic moment and the electric dipole moment of the $τ$-neutrino are calculated through the reaction $e^{+}e^{-}\to ν\bar νγ$ at the $Z_1$-pole, and in the framework of a left-right symmetric model. The results are based on the recent data reported by the L3 Collaboration at CERN LEP. We find that the bounds are almost independent o

Maxim. Yu. Khlopov, Sergei. G. Rubin, Alexander. S. Sakharov

We describe a mechanism of the primordial black holes formation that can explain the existence of a population of supermassive black holes in galactic bulges. The mechanism is based on the formation of black holes from closed domain walls. The origin of such domain walls could be a result of the evolution of an effectively massless scalar field during inflat

Kevin Wortman

We give a new proof of a theorem of Kleiner-Leeb: that any quasi-isometrically embedded Euclidean space in a product of symmetric spaces and Euclidean buildings is contained in a metric neighborhood of finitely many flats, as long as the rank of the Euclidean space is not less than the rank of the target. A bound on the size of the neighborhood and on the nu

Akikazu Hashimoto, Leopoldo Pando Zayas

We compare the entropy as a function of energy of excited strings and black strings in an asymptotically plane wave background at the level of the correspondence principle. For the plane wave supported by the NSNS 3-form flux, neither the entropy formula nor the cross-over scale is affected by the presence of the flux and the correspondence is found to hold.

Kevin Wortman

We show that S-arithmetic lattices in semisimple Lie groups with no rank one factors are quasi-isometrically rigid.

P. H. Frampton, S. T. Petcov, W. Rodejohann

The PMNS neutrino mixing matrix U_{PMNS} is in general a product of two unitary matrices U_{lep} and U_ν arising from the diagonalization of the charged lepton and neutrino mass matrices, U_{PMNS} = U^{\dagger}_{lep} U_ν. Assuming that U_ν is a bimaximal mixing matrix, we investigate the possible forms of U_{lep}. We identify three possible generic structure

Baruch Horovitz

Recent ESR data shows rotation of the antiferromagnetic (AF) easy axis in lightly doped layered cuprates upon lowering the temperature. We account for the ESR data and show that it has significant implications on spin and charge ordering according to the following scenario: In the high temperature phase AF domain walls coincide with (110) twin boundaries of

D. Bazeia, R. Menezes, J. G. Ramos

We search for regular tachyon kinks in an extended model, which includes the tachyon action recently proposed to describe the tachyon field. The extended model that we propose adds a new contribution to the tachyon action, and seems to enrich the present scenario for the tachyon field. We have found stable tachyon kinks of regular profile, which may appropri

Jerome Margueron, Jesus Navarro, Patrick Blottiau

It is shown that the large density fluctuations appearing at the onset of the first order nuclear liquid-gas phase transition can play an important role in the supernovae evolution. Due to these fluctuations, the neutrino gas may be trapped inside a thin layer of matter near the proto-neutron star surface. The resulting increase of pressure may induce strong

Vincent Desjacques, Adi Nusser

We present a model for one-dimensional (1D) matter power spectra in redshift space as estimated from data provided along individual lines of sight. We derive analytic expressions for these power spectra in the linear and nonlinear regimes, focusing on redshift distortions arising from peculiar velocities. In the linear regime, redshift distortions enhance th

Alberto Sesana, Francesco Haardt, Piero Madau, Marta Volonteri

We compute the expected gravitational wave signal from coalescing massive black hole (MBH) binaries at the center of galaxies in a hierarchical structure formation scenario in which seed holes of intermediate mass form far up in the dark halo merger tree. The merger history of DM halos and MBHs is followed from z=20 to the present in a LCDM cosmology. MBHs g

Leticia F. Cugliandolo

The aim of this report is to review a theoretical approach that has been proposed recently to describe dynamic fluctuations in glassy systems (work in collaboration with H. Castillo, C. Chamon, P. Charbonneau, J. L. Iguain, M. Kennett, D. Reichman and M. Sellitto). Firstly, I summarize some of the main features of the averaged and global non-equilibrium rela

F. R. Ferraro, A. Sollima, E. Pancino, M. Bellazzini

Using deep high-resolution multi-band images taken with the Very Large Telescope and the Hubble Space Telescope, we discovered a new anomalous sequence in the Color Magnitude Diagram of omega Cen. This feature appears as a narrow, well-defined Sub Giant Branch (SGB-a), which merges into the Main Sequence of the dominant cluster population at a magnitude sign

L. Santos, M. A. Baranov, J. I. Cirac, H. -U. Everts

We demonstrate the possibility of creating and controlling an ideal and \textit{trimerized} optical Kagomé lattice, and study the low temperature physics of various atomic gases in such lattices. In the trimerized Kagomé lattice, a Bose gas exhibits a Mott transition with fractional filling factors, whereas a spinless interacting Fermi gas at 2/3 filling beh

Zai-Zhe Zhong

In quantum mechanics and quantum information, to establish the orthogonal bases is a useful means. The existence of unextendible product bases impels us to study the `entanglement bases&#39; problems. In this paper, the concepts of entanglement bases and exact-entanglement bases are defined, and a theorem about exact-entanglement bases is given. We discuss t

Rossen I. Ivanov, Emil M. Prodanov

The field equations of the original Kaluza&#39;s theory are analyzed and it is shown that they lead to modification of Einstein&#39;s equations. The appearing extra energy-momentum tensor is studied and an example is given where this extra energy-momentum tensor is shown to allow four-dimensional Schwarzschild geometry to accommodate electrostatics. Such dev

Ryu Takayama, Takeo Hoshi, Takeo Fujiwara

For large scale electronic structure calculation, the Krylov subspace method is introduced to calculate the one-body density matrix instead of the eigenstates of given Hamiltonian. This method provides an efficient way to extract the essential character of the Hamiltonian within a limited number of basis set. Its validation is confirmed by the convergence pr

Vitor Cardoso, Oscar J. C. Dias, Jose&#39; P. S. Lemos

We find all the higher dimensional solutions of the Einstein-Maxwell theory that are the topological product of two manifolds of constant curvature. These solutions include the higher dimensional Nariai, Bertotti-Robinson and anti-Nariai solutions, and the anti-de Sitter Bertotti-Robinson solutions with toroidal and hyperbolic topology (Plebanski-Hacyan solu

Giovanni Felder, Roman Riser

We study a class of holomorphic matrix models. The integrals are taken over middle dimensional cycles in the space of complex square matrices. As the size of the matrices tends to infinity, the distribution of eigenvalues is given by a measure with support on a collection of arcs in the complex planes. We show that the arcs are level sets of the imaginary pa

T. Hyodo, A. Hosaka, M. J. Vicente Vacas, E. Oset

The photo-induced $K^*$ vector meson production is investigated for the study of the $Λ(1405)$ resonance. This reaction is particularly suited to the isolation of the second pole in the $Λ(1405)$ region which couples dominantly to the $\bar K N$ channel. We obtain the mass distribution of the $Λ(1405)$ which peaks at 1420 MeV, and differs from the nominal on

Rajesh R. Parwani

A nonlinear generalisation of Schrodinger&#39;s equation is obtained using information-theoretic arguments. The nonlinearities are controlled by an intrinsic length scale and involve derivatives to all orders thus making the equation mildly nonlocal. The nonlinear equation is homogeneous, separable, conserves probability, but is not invariant under spacetime

A. Adelswaerd, S. Wallentowitz

The dynamics of non-polar diatomic molecules interacting with a far-detuned narrow-band laser field, that only may drive rotational transitions, is studied. The rotation of the molecule is considered both classically and quantum mechanically, providing links to features known from the heavy symmetric top. In particular, quantum decoherence in the molecular r

R. M. Cavalcanti

We consider a massless scalar field obeying Dirichlet boundary conditions on the walls of a two-dimensional L x b rectangular box, divided by a movable partition (piston) into two compartments of dimensions a x b and (L-a) x b. We compute the Casimir force on the piston in the limit L -> infinity. Regardless of the value of a/b, the piston is attracted to th

D. Balciunas

A fundamental problem in evolutionary ecology research is to explain how different species coexist in natural ecosystems. This question is directly related with species trophic competition. However, competition theory, based on the classical logistic Lotka-Volterra equations, leads to erroneous conclusions about species coexistence. The reason for this is in

Lior Pachter, Bernd Sturmfels

One of the major successes in computational biology has been the unification, using the graphical model formalism, of a multitude of algorithms for annotating and comparing biological sequences. Graphical models that have been applied towards these problems include hidden Markov models for annotation, tree models for phylogenetics, and pair hidden Markov mod

J. Phillips, R. L. Mills, X. Chen

Water bath calorimetry was used to demonstrate one more peculiar phenomenon associated with a certain class of mixed gas plasmas termed resonant transfer, or RT plasmas. Specifically, He/H2 (10%) (500 mTorr), Ar/H2 (10%) (500 mTorr), and H2O(g) (500 and 200 mTorr) plasmas generated with an Evenson microwave cavity consistently yielded on the order of 50% mor

F. A. Farrelly, A. Petri, L. Pitolli, G. Pontuale

The Environmental Acoustic Reconnaissance and Sounding experiment (EARS), is composed of two parts: the Environmental Acoustic Reconnaissance (EAR) instrument and the Environmental Acoustic Sounding Experiment (EASE). They are distinct, but have the common objective of characterizing the acoustic environment of Mars. The principal goal of the EAR instrument

C. P. Bidinosti, J. Choukeife, G. Tastevin, A. Vignaud

Optical pumping of He-3 produces large (hyper) nuclear-spin polarizations independent of the magnetic resonance imaging (MRI) field strength. This allows lung MRI to be performed at reduced fields with many associated benefits, such as lower tissue susceptibility gradients and decreased power absorption rates. Here we present results of 2D imaging as well as

F. Ruggiero, M. Zobov

We give an overview of presentations and discussions during the Accelerator Working Group Session dedicated to High Luminosity Issues for a future upgrade of the Frascati e+e- Phi-Factory DAPhNE at the Workshop &#34;e+e- in the 1-2 GeV range: Physics and Accelerator Prospects&#34; held at Alghero (Italy) on 10-13 September 2003.

Ruediger Vaas

The secret network of the universe: How quantum geometry might complete Einstein&#39;s dream. - An informal introduction to quantum geometry (loop quantum gravity), spin networks, quantum black holes, and the work of Abhay Ashtekar, Carlo Rovelli, Lee Smolin and others.