June 2002 arXiv papers — page 5

Bringfried Stecklum, Thomas Henning, Markus Feldt, Hans-Ulrich Kaeufl

Imaging polarimetry is a useful tool to reveal the 3D structure of dust distributions and to localize embedded young stellar objects. We present maps of the linear polarization at 2.2 micron for three ultra-compact HII regions (G192.16-3.82, G331.28-0.19, G339.88-1.26) and the methanol maser source G305.21+0.21. From the polarization maps, we draw conclusion

Yu. L. Bukhmastova

A new catalog of 8382 close quasar-galaxy pairs is presented. The catalog was composed using published catalogs of quasars and active galactic nuclei containing 11358 objects, as well as the LEDA catalog of galaxies, which contains on the order of 100 thousand objects. The search for pairs was carried out in such a way that the linear distance between the ga

ANTARES collaboration

ANTARES is a project leading towards the construction and deployment of a neutrino telescope in the deep Mediterranean Sea. The telescope will use an array of photomultiplier tubes to detect the Cherenkov light emitted by muons resulting from the interaction with matter of high energy neutrinos. In the vicinity of the deployment site the ANTARES collaboratio

Patrick A. Woudt, Brian Warner

We present a status report on our high speed photometric survey of faint Cataclysmic Variables, which is concentrating on old novae.

Brian Warner

The observed properties of novae before and after eruption are discussed. The distribution of orbital periods of novae shows a concentration near 3.2 h, which resembles that of magnetic cataclysmic variables, and there is some evidence that many of the novae themselves are magnetic near that orbital period. Desynchronisation of polars by nova eruptions can l

Sachiyo Noda, Mine Takeuti

Approximately four thousand light curves of red variable stars in the LMC were selected from the 2.3-years duration MOA database by a period analysis using the Phase Dispersion Minimization method. Their optical features (amplitudes, periodicities, position in CMD) were investigated. Stars with large amplitues and high periodicities were distributed on the o

Mallory S. E. Roberts, Cindy R. Tam, Victoria M. Kaspi, Maxim Lyutikov

We present an X-ray and radio study of the wind nebula surrounding the central pulsar PSR J1811-1925 in the supernova remnant G11.2-0.3. Using high resolution data obtained with the Chandra X-ray observatory and with the VLA radio telescope we show the X-ray and radio emission is asymmetric around the pulsar, despite the latter's central position in the

Yaron Sheffer, David L. Lambert, S. R. Federman

We report the detection of fully resolved absorption lines of A-X bands from interstellar 12C17O and 12C18O, through high-resolution spectroscopy of X Per with the Space Telescope Imaging Spectrograph. The first ultraviolet measurement of an interstellar 12C17O column density shows that its isotopomeric ratio is 12C16O/12C17O = 8700 \pm 3600. Simultaneously,

E. Ryan-Weber, B. S. Koribalski, L. Staveley-Smith, H. Jerjen

The HI Parkes All-Sky Survey (HIPASS) is a blind 21-cm survey for extragalactic neutral hydrogen, covering the whole southern sky. The HIPASS Bright Galaxy Catalog (BGC; Koribalski et al. 2002) is a subset of HIPASS and contains the 1000 HI-brightest (peak flux density) galaxies. Here we present the 138 HIPASS BGC galaxies, which had no redshift measured pri

E. Kotoneva, C. Flynn, C. Chiappini, F. Matteucci

K-dwarfs have life-times older than the present age of the Galactic disc, and are thus ideal stars to investigate the disc's chemical evolution. We have developed several photometric metallicity indicators for K dwarfs, based an a sample of accurate spectroscopic metallicities for 34 disc and halo G and K dwarfs. The photometric metallicities lead us to

J. P. U. Fynbo, C. Ledoux, P. Moller, B. Thomsen

In 2000, we started the program ``Building the Bridge between Damped Ly-alpha Absorbers and Lyman-Break Galaxies: Ly-alpha Selection of Galaxies'' at the European Southern Observatory's Very Large Telescope. This project is an attempt to use Ly-alpha selection of high-z galaxies to bridge the gap between absorption- and emission-selected galaxies

Volker Ossenkopf, Mordecai-Mark Mac Low

We compare velocity structure in the Polaris Flare molecular cloud at scales ranging from 0.015 pc to 20 pc to simulations of supersonic hydrodynamic and MHD turbulence computed with the ZEUS MHD code. We use several different statistical methods to compare models and observations. The Delta-variance wavelet transform is most sensitive to characteristic scal

B. Simovic, P. C. Hammel, M. Hucker, B. Buchner

We report measurements of the longitudinal ($^{139}T_1^{-1}$) and transverse ($^{139}T_2^{-1}$) decay rates of the magnetization of $^{139}$La nuclei performed in a high quality single crystal of La$_{1.65}$Eu$_{0.2}$Sr$_{0.15}$CuO$_{4}$. We observe a dramatic slowing of the Cu 3d spins manifested as a sharp increase of both $^{139}T_1^{-1}$ and $^{139}T_2^{

Stefan C. Keller, M. S. Bessell, K. H. Cook, M. Geha

We present the photometric properties of 1279 blue variable stars within the LMC. Photometry is derived from the MACHO database. The lightcurves of the sample exhibit a variety of quasi-periodic and aperiodic outburst behavior. A characteristic feature of the photometric variation is that the objects are reddest when at maximum outburst. A subset of 102 obje

C. Markert, G. Torrieri, J. Rafelski

Hyperon resonances are becoming an extremely useful tool allowing the study of the properties of hadronic fireballs made in heavy ion collisions. Their yield, compared to stable particles with the same quark composition, depends on hadronization conditions. The resonance's short lifetime makes them ideal probes of the fireball chemical freeze-out mechani

WA98 Collaboration

Results on the study of localized fluctuations in the multiplicity of charged particles and photons produce 158A GeV/c Pb+Pb collisions are presented for four different centrality classes. The charged versus neutral particle multiplicity correlations in common phase space regions of varying azimuthal size are analyzed by two different methods. Various types

Alfred Scharff Goldhaber, Anton Rebhan, Peter van Nieuwenhuizen, Robert Wimmer

We consider the N=1 supersymmetric kink on a circle, i.e., on a finite interval with boundary or transition conditions which are locally invisible. For Majorana fermions, the single-particle Dirac Hamiltonian as a differential operator obeys simultaneously the three discrete symmetries of charge conjugation, parity, and time reversal. However, no single loca

Igor R. Klebanov, Marcus Spradlin, Anastasia Volovich

It has recently been observed that IIB string theory in the pp-wave background can be used to calculate certain quantities, such as the dimensions of BMN operators, as exact functions of the effective coupling lambda' = lambda/J^2. These functions interpolate smoothly between the weak and strong effective coupling regimes of N=4 SYM theory at large R cha

Luiz C. de Albuquerque, D. Dalmazi

We present both analytic and numerical results on the position of the partition function zeros on the complex magnetic field plane of the $q=2$ (Ising) and $q=3$ states Potts model defined on $ϕ^3 $ Feynman diagrams (thin random graphs). Our analytic results are based on the ideas of destructive interference of coexisting phases and low temperature expansion

Savitri V. Iyer, S. G. Rajeev

We derive a formula for the entropy of two dimensional incompressible inviscid flow, by determining the volume of the space of vorticity distributions with fixed values for the moments Q_k= \int_w(x)^k d^2 x. This space is approximated by a sequence of spaces of finite volume, by using a regularization of the system that is geometrically natural and connecte

Gary T. Horowitz, Joseph Polchinski

Time dependent orbifolds with spacelike or null singularities have recently been studied as simple models of cosmological singularities. We show that their apparent simplicity is an illusion: the introduction of a single particle causes the spacetime to collapse to a strong curvature singularity (a Big Crunch), even in regions arbitrarily far from the partic

Malcolm Fairbairn, Veronique Van Elewyck

It has recently been suggested that the existence of bare strange stars is incompatible with low scale gravity scenarios. It has been claimed that in such models, high energy neutrinos incident on the surface of a bare strange star would lead to catastrophic black hole growth. We point out that for the flat large extra dimensional case, the parts of paramete

Ahmed Ali, Enrico Lunghi

We study the implications of the recently improved upper limits on the branching ratios for the decays B -> rho gamma, expressed as R(rho gamma/K^* gamma) = BR(B -> rho gamma)/BR(B -> K^* gamma) <0.047. We work out the constraints that the current bound on R(rho gamma/K^* gamma) implies on the parameters of the quark mixing matrix in the standard model (SM).

Zvi Bern

In this review we describe a non-trivial relationship between perturbative gauge theory and gravity scattering amplitudes. At the semi-classical or tree level, the scattering amplitudes of gravity theories in flat space can be expressed as a sum of products of well defined pieces of gauge theory amplitudes. These relationships were first discovered by Kawai,

C. Florentino, J. Mourao, J. P. Nunes

We extend the coherent state transform (CST) of Hall to the context of the moduli spaces of semistable holomorphic vector bundles with fixed determinant over elliptic curves. We show that by applying the CST to appropriate distributions, we obtain the space of level k, rank n and genus one non-abelian theta functions with the unitarity of the CST transform b

Manuel Guedel

Radio astronomy has provided evidence for the presence of ionized atmospheres around almost all classes of non-degenerate stars. Magnetically confined coronae dominate in the cool half of the Hertzsprung-Russell diagram. Their radio emission is predominantly of non-thermal origin and has been identified as gyrosynchrotron radiation from mildly relativistic e

Rob Ivison, Thomas Greve, Ian Smail, James Dunlop

The SCUBA 8-mJy survey is the largest submm extragalactic mapping survey undertaken to date, centred on the Lockman Hole and ELAIS N2 regions. Here, we present new 1.4-GHz imaging of the depth and resolution necessary to reliably identify radio counterparts for 18 of 30 submm sources. Armed with this greatly improved positional information, we present and an

Viatcheslav Kharlamov, Frank Sottile

We introduce and begin the topological study of real rational plane curves, all of whose inflection points are real. The existence of such curves is a corollary of results in the real Schubert calculus, and their study has consequences for the important Shapiro and Shapiro conjecture in the real Schubert calculus. We establish restrictions on the number of r

P. Gandhi, C. S. Crawford, A. C. Fabian

We present near-infrared long-slit spectra of eight optically-dim X-ray sources obtained with ISAAC on the Very Large Telescope. Six of the sources have hard X-ray emission with a significant fraction of the counts emerging above 2 keV. All were discovered serendipitously in the fields of three nearby galaxy clusters observed with Chandra, and identified thr

S. E. Skipetrov

We formulate a Langevin description of dynamics of a speckle pattern resulting from the multiple scattering of a coherent wave in a nonlinear disordered medium. The speckle pattern exhibits instability with respect to periodic excitations at frequencies $Ω$ below some $Ω_{\mathrm{max}}$, provided that the nonlinearity exceeds some $Ω$-dependent threshold. A

Miguel Alcubierre, Bernd Bruegmann, Peter Diener, Michael Koppitz

Numerical relativity has faced the problem that standard 3+1 simulations of black hole spacetimes without singularity excision and with singularity avoiding lapse and vanishing shift fail after an evolution time of around 30-40M due to the so-called slice stretching. We discuss lapse and shift conditions for the non-excision case that effectively cure slice

Bang-Gui Liu

Using the accurate first-principle method within density-functional theory, we systematically study CrSb in the zincblende (zb) structure. The zb CrSb is predicted of robust half-metallic ferromagnetism (HMFM) with a magnetic moment of 3.000 $μ_B$ per formula. It is much better than other zb compounds with HMFM because its spin-flip gap reaches 0.774 eV at t

A. A. Nersesyan, A. M. Tsvelik

For two spatially anisotropic, SU(2)-invariant models of frustrated magnets in arbitrary space dimension we present a non-perturbative proof of the existence of neutral spin-1/2 excitations (spinons). In one model the frustration is static and based on fine tuning of the coupling constants, whereas in the other it is dynamic and does not require adjusting of

Zhongzhi Song, Kuang-Ta Chao

We study the exclusive decays of $B$ meson into P-wave charmonium states $χ_{cJ}(J=0,1)$ in the QCD factorization approach with light-cone distribution functions describing the mesons in the processes. For $B \to χ_{c1} K$ decay, we find that there are logarithmic divergences arising from nonfactorizable spectator interactions even at twist-2 order and the d

A. Buzulutskov

We show that physics of multi-GEM structures is rather complex, regarding the number of phenomena affecting detector performance. The high-pressure operation in noble gases and the ion feedback are considered in more detail. It is proposed that the dominant avalanche mechanism in He and Ne, at high pressures, is the associative ionization. Ion feedback effec

P. Astone, M. Bassan, P. Bonifazi, P. Carelli

Data obtained during five months of 2001 with the gravitational wave (GW) detectors EXPLORER and NAUTILUS were studied in correlation with the gamma ray burst data (GRB) obtained with the BeppoSAX satellite. During this period BeppoSAX was the only GRB satellite in operation, while EXPLORER and NAUTILUS were the only GW detectors in operation. No correlation

Yas-Hiro Quano

Presented are two kinds of integral solutions to the quantum Knizhnik-Zamolodchikov equations for the 2n-point correlation functions of the Heisenberg XYZ antiferromagnet. Our first integral solution can be obtained from those for the cyclic SOS model by using the vertex-face correspondence. By the construction, the sum with respect to the local height varia

Lorenzo Iorio

In this paper we present a rather extensive error budget for the difference of the perigees of a pair of supplementary SLR satellites aimed to the detection of the Lense-Thirring effect.

Jeng-Da Chai, D. Stroud, J. Hafner, G. Kresse

We calculate the dynamic structure factor S(k,omega) of liquid Ge (l-Ge) at temperature T = 1250 K, and of amorphous Ge (a-Ge) at T = 300 K, using ab initio molecular dynamics. The electronic energy is computed using density-functional theory, primarily in the generalized gradient approximation, together with a plane wave representation of the wave functions

Lorenzo Iorio

In this letter we further analyze the concept of the use of a pair of identical geodetic satellites placed in identical orbits except for the inclinations which should be supplementary for measuring the Lense-Thirring effect in the terrestrial gravitational field. It turns out that not only the sum of the nodes, as already proposed for the LAGEOS-LARES missi

Rong-Gen Cai

We consider a five-dimensional constant curvature black hole, which is constructed by identifying some points along a Killing vector in a five-dimensional AdS space. The black hole has the topology M_4 times S^1, its exterior is time-dependent and its boundary metric is of the form of a three-dimensional de Sitter space times a circle, which means that the d

Zhiguang Xiao, Hanqing Zheng

The naive use of higher order perturbation theory leads the left--hand cut integrals in $ππ$ dispersion relations~\cite{hjy,Xiao01} divergent. This problem is discussed and solved. Also we point out that the Adler zero condition imposes three constraints on the dispersion relations. The $σ$ pole position is determined using the improved method, $M_σ= 483\pm

T. Yoshida, X. J. Zhou, T. Sasagawa, W. L. Yang

Lightly-doped La$_{2-x}$Sr$_x$CuO$_4$ in the so-called &#34;insulating&#34; spin-glass/diagonal-stripe phase has been studied by angle-resolved photoemission spectroscopy. A quasi-particle (QP) peak crossing the Fermi level has been observed in the node direction of the d-wave superconducting gap, forming an &#34;arc&#34; of Fermi surface consistent with the

Omar Mustafa, Miloslav Znojil

The pseudo-perturbation shifted-l expansion technique PSLET is shown applicable in the non-Hermitian PT-symmetric context. The construction of bound states for several PT-symmetric potentials is presented, with special attention paid to V(r) = ir^3-alpha sqrt(ir) oscillators.

Zhi-zhong Xing

We propose a non-SO(10) modification of the Buchmueller-Wyler ansatz for neutrino mixing and leptogenesis, in which charged lepton, Dirac and Majorana neutrino mass matrices have fewer free parameters. Predictions of this new ansatz for three light neutrino masses, three lepton flavor mixing angles, the neutrinoless double-beta decay and the cosmological mat

M. Hotta

We argue that states with nontrivial horizontal charges of BTZ black hole can be excited by ordinary falling matter including Hawking radiation. The matter effect does not break the integrability condition of the charges on the horizon. Thus we are able to trace the proccesses in which the matter imprints the information on the horizon by use of the charged

Tim D. Cochran

The classical abelian invariants of a knot are the Alexander module, which is the first homology group of the the unique infinite cyclic covering space of S^3-K, considered as a module over the (commutative) Laurent polynomial ring, and the Blanchfield linking pairing defined on this module. From the perspective of the knot group, G, these invariants reflect

Subhash Kak

The problem of initializing phase in a quantum computing system is considered. The initialization of phases is a problem when the system is initially present in an entangled state and also in the application of the quantum gate transformations since each gate will introduce phase uncertainty. The accumulation of these random phases will reduce the effectiven

M. N. Sergeenko

Solution of the Schrödinger&#39;s equation in the zero order WKB approximation is analyzed. We observe and investigate several remarkable features of the WKB$_0$ method. Solution in the whole region is built with the help of simple connection formulas we derive from basic requirements of continuity and finiteness for the wave function in quantum mechanics. W

Andrey Grib, Georges Parfionov

The game in which acts of participants don&#39;t have an adequate description in terms of Boolean logic and classical theory of probabilities is considered. The model of the game interaction is constructed on the basis of a non-distributive orthocomplemented lattice. Mixed strategies of the participants are calculated by the use of probability amplitudes acc

Holger Mack, Matthias Freyberger

We investigate the dynamics of entanglement between two continuous variable quantum systems. The model system consists of two atoms in a harmonic trap which are interacting by a simplified s-wave scattering. We show, that the dynamically created entanglement changes in a steplike manner. Moreover, we introduce local operators which allow us to violate a Bell

K. Kowalski, K. Podlaski, J. Rembielinski

The detailed study of a quantum free particle on a pointed plane is performed. It is shown that there is no problem with a mysterious ``quantum anticentrifugal force&#34; acting on a free particle on a plane discussed in a very recent paper: M. A. Cirone et al, Phys. Rev. A 65, 022101 (2002), but we deal with a purely topological efect related to distinguish

C. S. Unnikrishnan

The present standard interpretation of quantum mechanics invokes nonlocality and state reduction at space-like separated points during measurements on entangled systems. While there is no understanding of the physical mechanism of such nonlocal state reduction, the experimental verifications of quantum correlations different from that predicted by local real

V. Arvind, K. R. Parthasarathy

Using the Weyl commutation relations over a finite field we introduce a family of error-correcting quantum stabilizer codes based on a class of symmetric matrices over the finite field satisfying certain natural conditions. When the field is GF(2) the existence of a rich class of such symmetric matrices is demonstrated by a simple probabilistic argument depe

Sangchul Oh, Soonchil Lee, Hai-woong Lee

We investigate quantum teleportation through noisy quantum channels by solving analytically and numerically a master equation in the Lindblad form. We calculate the fidelity as a function of decoherence rates and angles of a state to be teleported. It is found that the average fidelity and the range of states to be accurately teleported depend on types of no

Gilad Gour

Defining the observable ${\bf ϕ}$ canonically conjugate to the number observable ${\bf N}$ has long been an open problem in quantum theory. Here we show how to define the absolute phase observable ${\bf Φ}\equiv |{\bfϕ}|$ by suitably restricting the Hilbert space of $x$ and $p$ like variables. This ${\bf Φ}$ is actually the absolute value of the phase and ha

I. M. Kulic, H. Schiessel

Active (catalysed) and passive (intrinsic) nucleosome repositioning is known to be a crucial event during the transcriptional activation of certain eucaryotic genes. Here we consider theoretically the intrinsic mechanism and study in detail the energetics and dynamics of DNA-loop-mediated nucleosome repositioning, as previously proposed by Schiessel et al. (

W. Loveland, K. E. Gregorich, J. B. Patin, D. Peterson

We have searched for the production of element 112 in the reaction of 231 MeV 48Ca with 238U. We have not observed any events with a &#34;one event&#34; upper limit cross section of 1.6 pb for EVR-fission events and 1.8 pb for EVR-alpha events.

J. M. Burward-Hoy

Results of identified charged hadrons produced in Au+Au collisions at ${\sqrt{s_{NN}}} = 130$ GeV as a function of centrality are discussed. The $<{p_{T}}>$ of protons and antiprotons is significantly larger than in p--p collisions at the same center of mass energy. Its scaling with the number of participant nucleons, an increase of $20 \pm 5%$ from peripher

Francisco Vera

We will show that the complex shapes of snow crystals can be explained from a simple basic mechanism that is also responsible for the appearance of many others structures in nature. We expect that this new physical mechanism, that follows from minimizing the total stored energy, will permit to explain most of the features of snow crystal growth.

Henk van Beijeren, J. R. Dorfman

The topological pressure is evaluated for a dilute random Lorentz gas, in the approximation that takes into account only uncorrelated collisions between the moving particle and fixed, hard sphere scatterers. The pressure is obtained analytically as a function of a temperature-like parameter, beta, and of the density of scatterers. The effects of correlated c

Ioana Dumitriu, Alan Edelman

This paper constructs tridiagonal random matrix models for general ($β>0$) $β$-Hermite (Gaussian) and $β$-Laguerre (Wishart) ensembles. These generalize the well-known Gaussian and Wishart models for $β= 1,2,4$. Furthermore, in the cases of the $β$-Laguerre ensembles, we eliminate the exponent quantization present in the previously known models. We further d

Christian Mercat

We continue our investigation of Discrete Riemann Surfaces with the discussion of the discrete analogs of period matrices, Riemann&#39;s bilinear relations, exponential of constant argument, series and electrical moves. We show that given a refining sequence of critical maps, the discrete period matrix converges to the continuous one.

Joseph Kouneiher

This paper was withdrawn by the author due to an edition&#39;s rights

Greg Kuperberg

We show that every non-trivial tame knot or link in R^3 has a quadrisecant, i.e. four collinear points. The quadrisecant must be topologically non-trivial in a precise sense. As an application, we show that a nonsingular, algebraic surface in R^3 which is a knotted torus must have degree at least eight.

Yanguang Charles Li

Rigorous Melnikov analysis is accomplished for Davey-Stewartson II equation under singular perturbation. Unstable fiber theorem and center-stable manifold theorem are established. The fact that the unperturbed homoclinic orbit, obtained via a Darboux transformation, is a classical solution, leads to the conclusion that only local well-posedness is necessary

Yanguang Charles Li

The work [Li,99] is generalized to the singularly perturbed nonlinear Schrödinger (NLS) equation of which the regularly perturbed NLS studied in [Li,99] is a mollification. Specifically, the existence of Smale horseshoes and Bernoulli shift dynamics is established in a neighborhood of a symmetric pair of Silnikov homoclinic orbits under certain generic condi

J. Ginibre, G. Velo

We study the theory of scattering for the Maxwell-Schr&#34;odinger system in space dimension 3,in the Coulomb gauge.In the special case of vanishing asymptotic magnetic field,we prove the existence of modified wave operators for that system with no size restriction on the Schr&#34;odinger data and we determine the asymptotic behaviour in time of solutions in

Iustin Coanda

We show that a combination between a remark from the well known note of I.N. Bernstein, I.M. Gel&#39;fand and S.I. Gel&#39;fand and the idea, systematically investigated in a recent work of D. Eisenbud, G. Fløystad and F.-O. Schreyer, of taking Tate resolution over exterior algebras leads to quick proofs of the main results of these two papers. This combinat

F. J. Calderon-Moreno, L. Narvaez-Macarro

We find explicit free resolutions for the $\scr D$-modules ${\scr D} f^s$ and ${\scr D}[s] f^s/{\scr D}[s] f^{s+1}$, where $f$ is a reduced equation of a locally quasi-homogeneous free divisor. These results are based on the fact that every locally quasi-homogeneous free divisor is Koszul free, which is also proved in this paper

Apoloniusz Tyszka

Let ϕ((x_1,x_2),(y_1,y_2))=(x_1-y_1)^2+(x_2-y_2)^2. We say that f:R^2 -> C^2 preserves distance d>=0 if for each x,y \in R^2 ϕ(x,y)=d^2 implies ϕ(f(x),f(y))=d^2. We prove that if x,y \in R^2 and |x-y|=(2\sqrt{2}/3)^k \cdot (\sqrt{3})^l (k,l are non-negative integers) then there exists a finite set {x,y} \subseteq S(x,y) \subseteq R^2 such that each unit-dist

Y. Semenov

This essay contains three parts. The first part of essay focuses on the hypothesis of the functional semantic constructions (FSC-Hypothesis). This hypothesis explains that a language, a number, a money are the functional semantic constructions. In the second part the author considers the Mathematics with respect to the FSC-Hypothesis. Author turns in the sol

Ivan Mirković, Maxim Vybornov

We construct Nakajima&#39;s quiver varieties of type A in terms of affine Grassmannians of type A. This gives a compactification of quiver varieties and a decomposition of affine Grassmannians into a disjoint union of quiver varieties. Consequently, singularities of quiver varieties, nilpotent orbits and affine Grassmannians are the same in type A. The const

Chi-Wai Leung, Chi-Keung Ng

We prove a result concerning the inclusion of non-trivial invariant ideals inside non-trivial ideals of a twisted crossed product. We will also give results concerning the primeness and simplicity of crossed products of twisted actions of locally compact groups on $C^*$-algebras.

CheeWhye Chin

Let X be a smooth curve over a finite field of characteristic p, let l be a prime number different from p, and let L be an irreducible lisse l-adic sheaf on X whose determinant is of finite order. By a theorem of Lafforgue, for each prime number l&#39; different from p, there exists an irreducible lisse l&#39;-adic sheaf L&#39; on X which is compatible with

Greg Kuperberg

We consider Kasteleyn and Kasteleyn-Percus matrices, which arise in enumerating matchings of planar graphs, up to matrix operations on their rows and columns. If such a matrix is defined over a principal ideal domain, this is equivalent to considering its Smith normal form or its cokernel. Many variations of the enumeration methods result in equivalent matri

Dominic Joyce

This paper gives a leisurely introduction to Calabi-Yau manifolds and special Lagrangian submanifolds from the differential geometric point of view, followed by a survey of recent results on singularities of special Lagrangian submanifolds, and their application to the SYZ Conjecture. It is aimed at graduate students in Geometry, String Theorists, and others

Antti J. Niemi

We suggest that the extrinsic curvature and torsion of a bosonic string can be employed as variables in a two dimensional Landau-Ginzburg gauge field theory. Their interpretation in terms of the abelian Higgs multiplet leads to two different phases. In the phase with unbroken gauge symmetry the ground state describes open strings while in the phase with brok

J. F. Wheater, G. Vernizzi

We consider a class of multi-matrix models with an action which is O(D) invariant, where D is the number of NxN Hermitian matrices X_μ, μ=1,...,D. The action is a function of all the elementary symmetric functions of the matrix $T_{μν}=Tr(X_μX_ν)/N$. We address the issue whether the O(D) symmetry is spontaneously broken when the size N of the matrices goes t

Boris L. Altshuler

In the 6-dimensional model of warped compactification based on the euclidean AdS Reissner-Nordstrom metric it is possible to escape artificial 4-brane&#39;s stress-energy tensor anistropy necessary for fulfillment of Israel junction conditions by introducing in 3+1 spacetime of the cosmological constant which turns out to be ${}\sim G^2$ ($G$ - Newton&#39;s

Stanley J. Brodsky, Dae Sung Hwang, Ivan Schmidt

We show that the initial-state interactions from gluon exchange between the incoming quark and the target spectator system lead to leading-twist single-spin asymmetries in the Drell-Yan process. The QCD initial-state interactions produce a $T-$odd spin-correlation between the target spin and the virtual photon production plane which is not power-law suppress

Chin-Aik Lee, Qaisar Shafi, Zurab Tavartkiladze

We consider a 5D SUSY $SU(3)_c\times SU(2)_L\times U(1)_Y\times {\cal U}(1)$ model compactified on an $S^{(1)}/Z_2$ orbifold. To cancel anomalies arising from the presence of ${\cal U}(1)$, we employ a Chern-Simons term and also chiral fields which could reside on the brane or in the bulk depending on the model. The presence of ${\cal U}(1)$ symmetry leads t

C. Brenner Mariotto, M. B. Gay Ducati, G. Ingelman

We discuss the relative rates of different charmonium states and introduce an improved model for mapping the continuous ccbar mass spectrum on the physical charmonium resonances.

C. Brenner Mariotto, J. Damet, G. Ingelman

Models with essential non-perturbative QCD dynamics and describing Tevatron data on high-$p_\perp$ charmonium are extrapolated to give predictions of prompt J/psi production at the LHC. Differences of up to an order of magnitude occurs. An important point is here the treatment of higher order perturbative QCD effects.

C. Brenner Mariotto, M. B. Gay Ducati, G. Ingelman

Hard and soft QCD dynamics are both important in charmonium hadroproduction, as presented here through a next-to-leading order QCD matrix element calculation combined with the colour evaporation model. Observed $x_F$ and $p_\perp$ distributions of $J/ψ$ in hadroproduction are reproduced. Quite similar results can also be obtained with a Monte Carlo event gen

Johan Bijnens, Alexander Khodjamirian

We analyze the higher-twist effects and the SU(3)-flavour symmetry breaking in the correlation functions used to calculate form factors of pseudoscalar mesons in the QCD light-cone sum rule approach. It is shown that the Ward identities for these correlation functions yield relations between twist-4 two- and three-particle distribution amplitudes. In additio

X. Calmet

We present a model based on a SU(2) confining theory which is dual to the standard model. This duality allows to calculate the electroweak mixing angle and the Higgs boson mass. Possible tests of this duality are discussed.

H. V. Klapdor-Kleingrothaus

The new project GENIUS will cover a wide range of the parameter space of predictions of SUSY for neutralinos as cold dark matter. Together with DAMA it will be the only experiment which can probe the seasonal modulation signal. Concerning hot dark matter GENIUS will be able to fix the (effective) neutrino mass with high accuracy. A GENIUS Test Facility has j

H. V. Klapdor-Kleingrothaus

The GENIUS (Germanium in Liquid Nitrogen Underground Setup) project has been proposed in 1997 [KK-BEY97] as first third generation double beta decay project, with a sensitivity aiming down to a level of an effective neutrino mass of <m_ν> < 0.01eV or less. Such sensitivity is important to fix the structure of the neutrino mass matrix with high accuracy, whic

D. Schildknecht, M. Tentyukov, M. Kuroda, B. Surrow

The empirical scaling law, wherein the total photoabsorption cross section depends on the single variable eta=(Q^2+m_0^2)/Lambda^2(W^2), provides empirical evidence for saturation in the sense of sigma_{gamma* p}(W^2,Q^2)/sigma_{gamma p}(W^2) --> 1 for W^2 --> infinity at fixed Q^2. The total photoabsorption cross section is related to elastic diffraction in

Lee C. Loveridge

We employ the Weizsaecker-Williams method of virtual quanta to study disintegration of nuclei in magnetic field. We explore a variety of field configurations and conclude that for the energy range of interest for applications to cosmic rays (10^{18}-10^{21} eV) such disintegrations are not a significant source of energy or flux loss for any realistic acceler

B. Lucini, M. Teper, U. Wenger

We investigate the properties of the deconfinement transition in SU(4) and SU(6) gauge theories. We find that it is a `normal&#39; first order transition in both cases, from which we conclude that the transition is first order in the N->infinity limit. Comparing our preliminary estimates of the continuum values of Tc/sqrt(K) with existing values for SU(2) an

Jussara M. de Miranda

We discuss recent achievements in light scalar mesons spectroscopy through amplitude analysis of charm particle decay and its consequences. The high statistics clean samples of charmed mesons, in addition to it&#39;s definite J^P and mass, is turning these decays into a new important environment to study light meson physics. We give special attention to the

P. D. Dauncey

We present updated measurements of branching fractions and CP-violating asymmetries for neutral B meson decays to two-body final states of charged pions and kaons. The results are obtained from a data sample of about 60 million Y(4S) to BB decays collected between 1999 and 2001 by the BaBar detector at the Pep-II asymmetric-energy B Factory at SLAC. The samp

Lino Miramonti

Borexino is a large unsegmented calorimeter featuring 300 tons of liquid scintillator, contained in a 8.5 meter nylon vessel, viewed by 2200 PMTs. The main goal of Borexino is the study, in real time, of low energy solar neutrinos, and in particular, the monoenergetic neutrinos coming from $^7Be$, which is one of the missing links on the solar neutrino probl

Joerg Gayler

Results on the derivative of log(F_2) with respect to log(x) at fixed Q^2 are presented. The measured derivatives are within errors independent of x for Q^2 >= 0.85 GeV^2 and increase linearly with log(Q^2) for 0.0001 <= x <= 0.01 and Q^2 >= 3 GeV^2. The results are based on preliminary and published H1 data which at Q^2 below 2 GeV^2 are combined with NMC a

J. B. Griffiths, M. Santano-Roco

The physical situation of the collision and subsequent interaction of plane gravitational waves in a Minkowski background gives rise to a well-posed characteristic initial value problem in which initial data are specified on the two null characteristics that define the wavefronts. In this paper, we analyse how the Abel transform method can be used in practic

N. T. Karonis, B. Toonen, I. Foster

Application development for distributed computing &#34;Grids&#34; can benefit from tools that variously hide or enable application-level management of critical aspects of the heterogeneous environment. As part of an investigation of these issues, we have developed MPICH-G2, a Grid-enabled implementation of the Message Passing Interface (MPI) that allows a us

Ath. Kehagias

Motivated by Hubert&#39;s segmentation procedure we discuss the application of hidden Markov models (HMM) to the segmentation of hydrological and enviromental time series. We use a HMM algorithm which segments time series of several hundred terms in a few seconds and is computationally feasible for even longer time series. The segmentation algorithm computes

A. W. C. Lau, Keng-Hui Lin, A. G. Yodh

We compute the entropic interactions between two colloidal spheres immersed in a dilute suspension of semi-flexible rods. Our model treats the semi-flexible rod as a bent rod at fixed angle, set by the rod contour and persistence lengths. The entropic forces arising from this additional rotational degree of freedom are captured quantitatively by the model, a