May 2003 arXiv papers — page 25

Mark Goresky, Robert Kottwitz, Robert MacPherson

Assuming a certain "purity" conjecture, we derive a formula for the (complex) cohomology groups of the affine Springer fiber corresponding to any unramified regular semi-simple element. We use this calculation to present a complex analog of the fundamental lemma for function fields. We show that the "kappa" orbital integral which arises in th

Mischa Rudnev

It is well known that a generic small perturbation of a Liouville-integrable Hamiltonian system causes breakup of resonant and near-resonant invariant tori. A general approach to the simple resonance case in the convex real-analytic setting is developed, based on a new technique for solving the Hamilton-Jacobi equation. It is shown that a generic perturbatio

Mark Goresky, Robert Kottwitz, Robert MacPherson

The affine Springer fiber corresponding to a regular integral equivalued semisimple element admits a paving by vector bundles over Hessenberg varieties and hence its (Borel-Moore) homology is "pure".

Thomas Leistner

If the holonomy representation of an $(n+2)$--dimensional simply-connected Lorentzian manifold $(M,h)$ admits a degenerate invariant subspace its holonomy group is contained in the parabolic group $(\mathbb{R} \times SO(n))\ltimes \mathbb{R}^n$. The main ingredient of such a holonomy group is the SO(n)--projection $G:=pr_{SO(n)}(Hol_p(M,h))$ and one may ask

Gianni Dal Maso, Irene Fonseca, Giovanni Leoni, Massimiliano Morini

In this paper it is shown that higher order quasiconvex functions suitable in the variational treatment of problems involving second derivatives may be extended to the space of all matrices as classical quasiconvex functions. Precisely, it is proved that a smooth strictly 2-quasiconvex function with p-growth at infinity, p>1, is the restriction to symmetric

Rodney Y. Sharp, Nicole Nossem

This paper is concerned with tight closure in a commutative Noetherian ring $R$ of prime characteristic $p$, and is motivated by an argument of K. E. Smith and I. Swanson that shows that, if the sequence of Frobenius powers of a proper ideal $I$ of $R$ has linear growth of primary decompositions, then tight closure (of $I$) commutes with localization at the

Gabriella B"ohm, Korn'el Szlach'anyi

We study Frobenius 1-morphisms $ı$ in an additive bicategory $\c$ satisfying the depth 2 condition. We show that the 2-endomorphism rings $\c^2(ı\x\ib,ı\x\ib)$ and $\c^2(\ib\xı,\ib\xı)$ can be equipped with dual Hopf algebroid structures. We prove also that a Hopf algebroid appears as the solution of the above abstract symmetry problem if and only if it poss

Heide Gluesing-Luerssen, Wiland Schmale

After a discussion of the Griesmer and Heller bound for the distance of a convolutional code we present several codes with various parameters, over various fields, and meeting the given distance bounds. Moreover, the Griesmer bound is used for deriving a lower bound for the field size of an MDS convolutional code and examples are presented showing that, in m

Kevin O'Bryant

Denote the sequence ([ (n-x&#39;) / x ])_{n=1}^\infty by B(x, x&#39;), a so-called Beatty sequence. Fraenkel&#39;s Partition Theorem gives necessary and sufficient conditions for B(x, x&#39;) and B(y, y&#39;) to tile the positive integers, i.e., for B(x, x&#39;) \cap B(y, y&#39;) = \emptyset and B(x, x&#39;) \cup B(y, y&#39;) = {1,2, 3, ...}. Fix 0 < x < 1,

S. Hofmann, A. Iosevich

We prove the following variant of the Falconer conjecture in the plane. If the dimension of a compact planar set is greater than one, then the distance set with respect to almost every ellipse has positive Lebesgue measure.

George Boros, Olivier Espinosa, Victor H. Moll

Beginning with Hermite&#39;s integral representation of the Hurwitz zeta function, we derive explicit expressions in terms of elementary, polygamma, and negapolygamma functions for several families of integrals of the type $\int_0^\infty f(t)K(q,t)dt$ with kernels $K(q,t)$ equal to $(e^{2πq t}-1)^{-1}$, $(e^{2πq t}+1)^{-1}$, and $(\sinh(2πq t)^{-1}$.

Marcus Tressl

Let M be a polynomially bounded, o-minimal structure with archimedean prime model, for example if M is a real closed field. Let C be a convex and unbounded subset of M. We determine the first order theory of the structure M expanded by the set C. We do this also over any given set of parameters from M, which yields a description of all subsets of M^n, defina

Leonardo Biliotti, Anna Gori

The main result of the paper is the complete classification of the compact connected Lie groups acting coisotropically on complex Grassmannians. This is used to determine the polar actions on the same manifolds.

Viktor L. Ginzburg, Basak Z. Gurel

The main theme of this paper is a relative version of the almost existence theorem for periodic orbits of autonomous Hamiltonian systems. We show that almost all low levels of a function on a geometrically bounded symplectically aspherical manifold carry contractible periodic orbits of the Hamiltonian flow, provided that the function attains its minimum alon

H. van Hees

We give a simplified proof for the perturbative renormalizability of theories with massive vector particles. For renormalizability it is sufficient that the vector particle is treated as an gauge field, corresponding to an Abelian gauge group. Contrary to the non-Abelian case one does not need the Higgs mechanism to create the appropriate mass terms. The pro

Lluis Ametller, Josep Maria Pons, Pere Talavera

We discuss the existence of glueball states for N=1 SYM within the Maldacena-Nunez model. We find that for this model the existence of an area law in the Wilson loop operator does not imply the existence of a discrete glueball spectrum. We suggest that implementing the model with an upper hard cut-off can amend the lack of spectrum. As a result the model can

D. Grumiller

Dilaton gravity in two dimensions is briefly reviewed from the perspective of three dilaton potentials: One determines classical physics (&#34;the good&#34;, denoted by w), the second is relevant for semi-classical (and quantum) effects (&#34;the muggy&#34;, denoted by I) and the third could be responsible for nonperturbative quantum effects (&#34;the bad&#3

B. Altschul

We consider the fermionic bound states associated with a soliton-antisoliton pair in 1+1 dimensions which have zero energy when the solitons are infinitely far apart. We calculate the energies of these states when the solitons are separated by a finite distance. The energies decay exponentially with the distance between the soliton and antisoliton. When the

A. Yu. Smirnov

The MSW (Mikheyev-Smirnov-Wolfenstein) effect is the effect of transformation of one neutrino species (flavor) into another one in a medium with varying density. Three basic elements of the effect include: the refraction of neutrinos in matter, the resonance (level crossing) and the adiabaticity. The key notion is {\it the neutrino eigenstates} in matter. Ph

Karol Kolodziej

Some features of a program &#39;eett6f&#39; for top quark pair production and decay into six fermions at linear colliders are discussed. Lowest order standard model predictions for cross sections of some six fermion channels and for the top quark decay width are confronted with the predictions obtained within a model with an anomalous Wtb coupling. The quest

K. Hagiwara, E. Kou, C. -F. Qiao

Exclusive quarkonium pair production in electron-positron collisions is studied in non-relativistic QCD. The obtained cross section for J/ψ+ η_c production in the leading order is confronted against the recent measurements by the Belle Collaboration at KEKB. It is shown that a large renormalization K-factor is necessary to explain the experimental data. We p

A. Patkos, Zs. Szep, P. Szepfalusy

By assuming certain analytic properties of the propagator, it is shown that universal features of the spectral function including threshold enhancement arise if a pole describing a particle at high temperature approaches in the complex energy plane the threshold position of its two-body decay with the variation of T. The case is considered, when one can disr

Masaharu Iwasaki, Hiyoshi Kiuchi

The chiral phase transition at finite temperature and density is discussed in the framework of the QCD-like gauge field theory. The thermodynamical potential is investigated using a variational approach. Latent heat generated in the first-order phase transition is calculated. It is found that the latent heat is enhanced near the tricritical point and is more

Masaharu Iwasaki, Shin-Ichi Nawa, Takayoshi Sanada, Fujio Takagi

We calculate the mass spectrum and the decay widths of glueballs in the flux tube model. The glueball is assumed to be a closed flux tube. The breathing motion and the rotational motion are investigated using the WKB approximation. The calculated spectra is consistent with those by lattice QCD. The decay widths are also computed using Schwinger mechanism and

A. Mueller

Below the saturation momentum the sea quark occupation number reaches a pure number, independent of any parameters in QCD, reminiscent of a Pauli Principle result. We argue, however, that the Pauli Principle plays no role in the result.

G. L. Kane, Brent D. Nelson, Lian-Tao Wang, Ting T. Wang

We study the implications of the absence of a direct discovery of a Higgs boson at LEP. First we exhibit 15 physically different ways in which one or more Higgs bosons lighter than the LEP limit could still exist. In the minimal supersymmetric standard model (MSSM) all of these, as well as the cases where the Higgs mass equals or exceeds 115 GeV, seem fine-t

Christian Rosenbleck

The precise knowledge of the beam energy, E_beam, at the LEP collider is important to reduce the systematic uncertainty on the W mass. The measurements by the LEP energy group can be cross checked using Z recoil events. Preliminary results of the four LEP experiments ALEPH, DELPHI, L3, and OPAL are presented. The combination of the results shows no significa

Karim A. Malik, Maria Rodriguez-Martinez, David Langlois

We study the definition of perturbations in the presence of a submanifold, like e.g. a brane. In the standard theory of cosmological perturbations, one compares quantities at the same coordinate points in the non-perturbed and the perturbed manifolds, identified via a (non-unique) mapping between the two manifolds. In the presence of a physical submanifold o

Gianni Franceschini, Viliam Geffert

We present the first in-place algorithm for sorting an array of size n that performs, in the worst case, at most O(n log n) element comparisons and O(n) element transports. This solves a long-standing open problem, stated explicitly, e.g., in [J.I. Munro and V. Raman, Sorting with minimum data movement, J. Algorithms, 13, 374-93, 1992], of whether there exis

V. Apaja, E. Krotscheck

We design models for helium in matrices like aerogel, Vycor or Geltech from a manifestly microscopic point of view. For that purpose, we calculate the dynamic structure function of 4He on Si substrates and between two Si walls as a function of energy, momentum transfer, and the scattering angle. The angle--averaged results are in good agreement with the neut

R. Saniz, B. Barbiellini, A. B. Denison, A. Bansil

We discuss an exactly solvable model Hamiltonian for describing the interacting electron gas in a quantum dot. Results for a spherical square well confining potential are presented. The ground state is found to exhibit striking oscillations in spin polarization with dot radius at a fixed electron density. These oscillations are shown to induce characteristic

D. R. Lee, C. S. Nelson, J. C. Lang, C. T. Venkataraman

The theoretical formulation of x-ray resonant magnetic scattering from rough surfaces and interfaces is given for the diffuse (off-specular) scattering, and general expressions are derived in both the Born approximation (BA) and the distorted-wave Born approximation (DWBA) for both single and multiple interfaces. We also give in the BA the expression for off

D. R. Lee, D. Haskel, Y. Choi, J. C. Lang

The theoretical formulation of x-ray resonant magnetic scattering from rough surfaces and interfaces is given for specular reflectivity. A general expression is derived for both structurally and magnetically rough interfaces in the distorted-wave Born approximation (DWBA) as the framework of the theory. For this purpose, we have defined a ``structural&#39;&#

Yongkyung Kwon, K. Birgitta Whaley

We present a microscopic quantum analysis for rotational constants of the OCS-H$_2$ complex in helium droplets using the local two-fluid theory in conjunction with path integral Monte Carlo simulations. Rotational constants are derived from effective moments of inertia calculated assuming that motion of the H$_2$ molecule and the local non-superfluid helium

S. Kotochigova, P. S. Julienne, E. Tiesinga

The relativistic configuration interaction valence bond method has been used to calculate permanent and transition electric dipole moments of the KRb heteronuclear molecule as a function of internuclear separation. The permanent dipole moment of the ground state $X^1Σ^+$ potential is found to be 0.30(2) $ea_0$ at the equilibrium internuclear separation with

Sergio Caracciolo, Andrea Gambassi, Massimiliano Gubinelli, Andrea Pelissetto

In a recent Letter Albano and Saracco study the dynamic critical behavior of some anisotropic driven lattice gases by Monte Carlo (MC) simulations. In this Comment we point out that the Ansätze they use to relate the measured scaling exponents with the critical exponents analytically computed within different field-theoretical approaches do not take properly

V. R. Manfredi, V. Penna, L. Salasnich

In this paper we investigate the local and global spectral properties of the triaxial rigid rotator. We demonstrate that, for a fixed value of the total angular momentum, the energy spectrum can be divided into two sets of energy levels, whose classical analog are librational and rotational motions. By using diagonalization, semiclassical and algebric method

M. Fasolo, P. Sollich

We calculate the phase behavior of hard spheres with size polydispersity, using accurate free energy expressions for the fluid and solid phases. Cloud and shadow curves, which determine the onset of phase coexistence, are found exactly by the moment free energy method, but we also compute the complete phase diagram, taking full account of fractionation effec

S. Majumdar, M. R. Lees, G. Balakrishnan, D. McK Paul

The magnetic behavior of the heavy fermion superconductor CeCoIn5 has been investigated. The low field magnetization data show flux jumps in the mixed state of the superconducting phase in a restricted range of temperature. These flux jumps begin to disappear below 1.7 K, and are completely absent at 1.5 K. The magnetization loops are asymmetric, suggesting

Freddy Bouchet, Thierry Dumont

We explain the emergence and stability of the most important jets and vortices, in the highly turbulent Jupiter&#39;s atmosphere, by a statistical mechanics of the potential vorticity mixing. Using the Quasi-Geostrophic 1-1/2 layer, with topography, when the Rossby deformation radius is small, we predict strong jets. These jets can be either zonal, or closed

Freddy Bouchet

We consider the modeling of the effect of unresolved scales, for two-dimensional and geophysical flows. We first show that the effect of small scales on a coarse-grained field, can be approximated at leading order, by the effect of the strain tensor on the gradient of the vorticity, which exactly conserves the energy. We show that this approximation would le

Y. Nakajima, K. Izawa, Y. Matsuda, S. Uji

The normal-state Hall effect and magnetoresisitance (MR) have been measured in the quasi-2D heavy fermion superconductor CeCoIn_5. In the non-Fermi liquid region where the reistivity rho_xx exhibits an almost perfect T-linear dependence, the Hall angle varies as cot theta_H propto T^2 and the MR displays a strong violation of Kohler&#39;s rule. We demonstrat

M. Stopa, W. G. van der Wiel, S. De Franceschi, S. Tarucha

We quantitatively describe the main features of the magnetically induced conductance modulation of a Kondo quantum dot -- or chessboard pattern -- in terms of a constant-interaction double quantum dot model. We show that the analogy with a double dot holds down to remarkably low magnetic fields. The analysis is extended by full 3D spin density functional cal

M. J. Qin, S. Keshavarzi, S. Soltanian, X. L. Wang

Sample size dependent critical current density has been observed in magnesium diboride superconductors. At high fields, larger samples provide higher critical current densities, while at low fields, larger samples give rise to lower critical current densities. The explanation for this surprising result is proposed in this study based on the electric field ge

V. Ryzhii, V. Vyurkov

We discuss the feasibility of absolute negative conductivity (ANC) in two-dimensional electron systems (2DES) stimulated by microwave radiation in transverse magnetic field. The mechanism of ANC under consideration is associated with the electron scattering on acoustic piezoelectric phonons accompanied by the absorption of microwave photons. It is demonstrat

Y. Morita, H. Yamauchi, M. Karppinen

The roles of aliovalent Ca(II)-for-Y(III) substitution and high-pressure-oxygen annealing in the process of &#34;superconducterizing&#34; the Co-based layered copper oxide, CoSr2(Y1-xCax)Cu2O7+d (Co-1212), were investigated. The as-air-synthesized samples up to x = 0.4 were found essentially oxygen stoichiometric (-0.03 <= d <= 0.00). These samples, however,

Sergiy Libert, Vyacheslav Gorshkov, Dan Goia, Egon Matijevic

The recently developed two-stage growth model of synthesis of monodispersed polycrystalline colloidal particles is utilized and improved to explain growth of uniform cadmium sulfide spheres. The model accounts for the coupled processes of nucleation, which yields nanocrystalline precursors, and aggregation of these subunits to form the final particles. The k

M. T. Batchelor, X. -W. Guan, A. Foerster, A. P. Tonel

An integrable quantum spin ladder based on the SU(4) symmetry algebra with boundary defects is studied in the framework of boundary integrability. Five nontrivial solutions of the reflection equations lead to different boundary impurities. In each case the energy spectrum is determined using the quantum inverse scattering method. The thermodynamic properties

J. K. O&#39;Neill, J. Dubinski

We examine the observable properties of simulated barred galaxies including radial mass profiles, edge-on structure and kinematics, bar lengths and pattern speed evolution for detailed comparison to real systems. We have run several simulations in which bars are created through inherent instabilities in self-consistent simulations of a realistic disc+halo ga

David S. De Young

Recent suggestions that buoyant radio emitting cavities in the intracluster medium can cause significant reheating of cooling flows are re-examined when the effects of the intracluster magnetic field are included. Expansion of the cavity creates a tangential magnetic field in the ICM around the radio source, and this field can suppress instabilities that mix

Hyesook Lee, Dongsu Ryu, Jongsoo Kim, T. W. Jones

We have studied forced turbulence of compressible magnetohydrodynamic (MHD) flows through two-dimensional simulations with different numerical resolutions. First, hydrodynamic turbulence with Mach number $<M_s >_{\rm init} \equiv < v >_{\rm rms}/ c_s = 1$ and density compression ${< δρ/ ρ>}_{\rm rms} \simeq 0.45$ was generated by enforcing a random force. Th

Dongsu Ryu, Hyesung Kang, Eric Hallman, T. W. Jones

We study the properties of cosmological shock waves identified in high-resolution, N-body/hydrodynamic simulations of a $Λ$CDM universe and their role on thermalization of gas and acceleration of nonthermal, cosmic ray (CR) particles. External shocks form around sheets, filaments and knots of mass distribution when the gas in void regions accretes onto them.

M. V. McSwain

HD 16429 A is a triple star system consisting of a single-lined spectroscopic binary and a widely separated third component, previously identified via speckle interferometry. Here I present the first orbital elements for the unblended spectroscopic binary as well as estimates of the spectral types and relative flux contributions for each visible component ba

M. Dulick, C. W. Bauschlicher,, Adam Burrows, C. M. Sharp

We calculate new line lists and opacities for the $F^4Δ_i-X^4Δ_i$ transition of FeH. The 0-0 band of this transition is responsible for the Wing-Ford band seen in M-type stars, sunspots and brown dwarfs. The new Einstein A values for each line are based on a high level ab initio calculation of the electronic transition dipole moment. The necessary rotational

R. S. Schnerr, T. Reerink, M. van der Klis, J. Homan

We present results of an analysis of all 480 ks of Rossi X-ray Timing Explorer Proportional Counter Array data obtained from 17 May 1998 to 11 October 1998 on the luminous low mass X-ray binary GX 13+1. We analysed the spectral properties in colour-colour diagrams (CDs) and hardness-intensity diagrams (HIDs) and fitted the power spectra with a multi-Lorentzi

A. W. McConnachie, M. J. Irwin, R. A. Ibata, A. M. N. Ferguson

The wide-field CCD camera at the CFH telescope was used to survey the giant stellar stream in the Andromeda galaxy, resolving stars down the red giant branch in M31 to I ~ 25, a magnitude deeper than our previous INT survey of this galaxy and extending 1 degree further out. The stream is seen to extend out to the south-east of M31 as far as we have surveyed

P. Borde, D. Rouan, A. Leger

COROT will be the first high precision photometric satellite to be launched with the aim of detecting exoplanets by the transit method. In this paper, we present the simulations we have carried out in order to assess the detection capability of COROT. Using the model of stellar population synthesis of the Galaxy developed at Besancon Observatory (Robin & Cre

Jean-Marc Petit, Olivier Mousis

Given the large orbital separation and high satellite-to-primary mass ratio of all known Kuiper Belt Object (KBO) binaries, it is important to reassess their stability as bound pairs with respect to several disruptive mechanisms. Besides the classical shattering and dispersing of the secondary due to a high-velocity impact, we considered the possibility that

John McMillan

John Barton was one of the experimental founders of particle astrophysics, working in deep underground locations all over the world. This note combines the obituary published in The Independent with a complete list of his publications.

D. M. Crenshaw, S. B. Kraemer, J. R. Gabel, J. S. Kaastra

We present new UV spectra of the nucleus of the Seyfert 1 galaxy NGC 5548, which we obtained with the Space Telescope Imaging Spectrograph at high spectral resolution, in conjunction with simultaneous Chandra X-ray Observatory spectra. Taking advantage of the low UV continuum and broad emission-line fluxes, we have determined that the deepest UV absorption c

Torsten A. Ensslin

Many compact radio sources like quasars, blazars, radio galaxies, and micro-quasars emit circular polarisation (CP) with surprising temporal persistent handedness. We propose that the CP is caused by Faraday conversion of linear polarisation synchrotron light which propagates along a line-of-sight through helical magnetic fields. Jet outflows from radio gala

M. Sandri, F. Villa, R. Nesti, C. Burigana

The study of Cosmic Microwave Background (CMB) anisotropies represents one of the most powerful Cosmological tools. After the great success of the two NASA&#39;s satellite missions COBE and WMAP, Planck represents the third generation of mm-wave instruments designed for space observations of CMB anisotropies within the new Cosmic Vision 2020 ESA Science Prog

Suzanne Talon, Corinne Charbonnel

We examine the generation of gravity waves by the surface convection zone of low-mass main sequence stars with solar metallicity. It is found that the total momentum luminosity in waves rises with stellar mass, up to the quasi-disappearance of the convection zone around 6500K (corresponding to a mass of about 1.4 Msun for solar metallicity) where the luminos

Juergen Ott, Crystal L. Martin, Fabian Walter

Deep Chandra observations (53 ks, ACIS-S3) of NGC 3077, a starburst dwarf galaxy in the M 81 triplet, resolve the X-ray emission from several supershells. The emission is brightest in the cavities defined by expanding shells detected previously in H alpha emission (Martin 1998). Thermal emission models fitted to the data imply temperatures ranging from ~1.3

Nadya Gorlova, Michael R. Meyer, Jim Liebert, George H. Rieke

We investigate the sensitivity to temperature and gravity of the strong absorption features in the J- and K-band spectra of substellar objects. We compare the spectra of giants and young M dwarfs (of low gravity) to field M and L dwarfs (of high gravity) and to model spectra from the Lyon group. We find that low-resolution spectra of M4 - M9 stars and young

A. Y. Poludnenko, K. K. Dannenberg, R. P. Drake, A. Frank

We present a design for high energy density laboratory experiments studying the interaction of hypersonic shocks with a large number of inhomogeneities. These ``clumpy&#39;&#39; flows are relevant to a wide variety of astrophysical environments including the evolution of molecular clouds, outflows from young stars, Planetary Nebulae and Active Galactic Nucle

Aldo Morselli

The energy domain between 10 MeV and hundreds of GeV is an essential one for the multifrequency study of extreme astrophysical sources. The understanding of spectra of detected gamma rays is necessary for developing models for acceleration, emission, absorption and propagation of very high energy particles at their sources and in space. After the end of EGRE

Marek Szydlowski, Wojciech Czaja

Assuming equation of state for quintessential matter: $p=w(z)ρ$, we analyse dynamical behaviour of the scale factor in FRW cosmologies. It is shown that its dynamics is formally equivalent to that of a classical particle under the action of 1D potential $V(a)$. It is shown that Hamiltonian method can be easily implemented to obtain a classification of all co

M. J. Bhaseen, A. M. Tsvelik

Recent studies indicate that the weakly coupled spin-1/2 Heisenberg antiferromagnet with next nearest neighbor frustration supports massive spinons when suitably tuned. The straightforward SU(N) generalization of the low energy ladder Hamiltonian yields two independent SU(N) Thirring models with N-1 multiplets of massive ``spinon&#39;&#39; excitations. We st

Noam Soker

I suggest that the behavior of the photospheric opacity in oxygen-rich (similar to solar abundance) upper asymptotic giant branch stars may cause these stars to substantially expand for a few thousand years. I term this process over-expansion. This may occur when the photospheric (effective) temperature drops to Tp~3000K, and because the opacity sharply incr

J. Mannik, J. E. Lukens

We report on the effect of the back-action of a Single Cooper Pair Transistor electrometer (E) on the measurement of charge on the island of a superconducting box (B). The charge is e-periodic in the gate bias of B when E is operated near voltages 2Delta/e or 4Delta/e. We show that this is due to quasiparticle poisoning of B at a rate proportional to the num

Seongchun Kwon

We show that the moduli space of genus zero stable maps is a real projective variety if the target space is a smooth convex real projective variety. We show that evaluation maps, forgetful maps are real morphisms. We analyze the real part of the moduli space.

C. J. Horowitz, M. A. Perez-Garcia

Advances in neutrino transport allow realistic neutrino interactions to be incorporated into supernova simulations. We add tensor couplings to relativistic RPA calculations of neutrino opacities. Our results reproduce free-space neutrino-nucleon cross sections at low density, including weak magnetism and recoil corrections. In addition, our opacities are the

G. A. Souliotis, D. V. Shetty, M. Veselsky, G. Chubarian

The scaling of the yields of heavy projectile residues from the reactions of 25 MeV/nucleon 86Kr projectiles with 124Sn,112Sn and 64Ni, 58Nitargets is studied. Isotopically resolved yield distributions of projectile fragments in the range Z=10-36 from these reaction pairs were measured with the MARS recoil separator in the angular range 2.7-5.3 degrees. The

C. E. Grant, M. W. Bautz, G. Chartas, G. P. Garmire

Gravitational lenses that produce multiple images of background quasars can be an invaluable cosmological tool. Deriving cosmological parameters, however, requires modeling the potential of the lens itself. It has been estimated that up to a quarter of lensing galaxies are associated with a group or cluster which perturbs the gravitational potential. Detecti

S. Satheesh

This paper proves that if a discrete distribution is infinitely divisible (ID) with integer-valued components, then it has a mass at the origin, which also implies why certain ID discrete laws do not have gaps in its support. We argue that discrete laws also can be stable and such laws do have domain of attraction. Then we give certain recent developments an

Aditi Sen De, Ujjwal Sen, Marek Zukowski

The technique of quantum repeaters is a promising candidate for sending quantum states over long distances through a lossy channel. The usual discussions of this technique deals with only a finite dimensional Hilbert space. However the qubits with which one implements this procedure will &#34;ride&#34; on continuous degrees of freedom of the carrier particle

V. N. Senoguz, Q. Shafi

We reconsider a class of well motivated supersymmetric models in which inflation is associated with the breaking of a gauge symmetry G to H, with the symmetry breaking scale M~10^16 GeV. Starting with a renormalizable superpotential, we include both radiative and supergravity corrections to derive the inflationary potential. The scalar spectral index n_s can

Mu-Chun Chen, K. T. Mahanthappa

Several ideas for solving the problem of fermion mass hierarchy and mixing and specific supersymmetric models that realize it are reviewed. In particular, we discuss many models based on SO(10) in four dimensions combined with a family symmetry to accommodate fermion mass hierarchy and mixing, including the case of neutrinos. These models are compared and va

S. Dawson, C. Jackson, L. H. Orr, L. Reina

We present in detail the calculation of the O(alpha_s^3) inclusive total cross section for the process pp -> t-tbar-h, in the Standard Model, at the CERN Large Hadron Collider with center-of-mass energy sqrt(s_H)=14 TeV. The calculation is based on the complete set of virtual and real O(alpha_s) corrections to the parton level processes q-qbar -> t-tbar-h an

H. Davoudiasl, J. L. Hewett, T. G. Rizzo

We study the effects of including brane localized curvature terms in the Randall-Sundrum (RS) model of the hierarchy. This leads to the existence of brane localized kinetic terms for the graviton. Such terms can be induced by brane and bulk quantum effects as well as Higgs-curvature mixing on the brane. We derive the modified spectrum of Kaluza-Klein (KK) gr

Harald Grosse, Raimar Wulkenhaar

Solving the exact renormalisation group equation a la Wilson-Polchinski perturbatively, we derive a power-counting theorem for general matrix models with arbitrarily non-local propagators. The power-counting degree is determined by two scaling dimensions of the cut-off propagator and various topological data of ribbon graphs. As a necessary condition for the

C. R. Rotundu, H. Tsujii, Y. Takano, B. Andraka

The magnetic phase diagram of PrOs$_4$Sb$_{12}$ has been investigated by specific heat measurements between 8 and 32 T. A new Schottky anomaly due to excitations between two lowest crystalline-electric-field (CEF) singlets, has been found for both $H \parallel (100)$ and $H \parallel (110)$ above the field where the field-induced ordered phase (FIOP) is supp

V. Azcoiti, A. Galante, V. Laliena

Assuming that a quantum field theory with a $θ$-vacuum term in the action shows non-trivial $θ$-dependence and provided that some reasonable properties of the probability distribution function of the order parameter hold, we argue that the theory either breaks spontaneously CP at $θ= π$ or shows a singular behavior at some critical $θ_c$ between 0 and $π$. T

Robert L. Bryant

This article consists of some loosely related remarks about the geometry of G_2-structures on 7-manifolds and is partly based on old unpublished joint work with two other people: F. Reese Harvey and Steven Altschuler. Much of this work has since been subsumed in the work of Hitchin \cite{MR02m:53070} and Joyce \cite{MR01k:53093}. I am making it available now

Klaus Zahn, Georg Maret, Carsten Russ, Hans Hennig von Grunberg

We use video microscopy to follow the phase-space trajectory of a two-dimensional colloidal model liquid and calculate three-point correlation functions from the measured particle configurations. Approaching the fluid-solid transition by increasing the strength of the pair-interaction potential, one observes the gradual formation of a crystal-like local orde

M. Eisterer, S. Haindl, T. Wojcik, H. W. Weber

We present a novel technique for the investigation of local variations of the critical current density in large bulk superconductors. In contrast to the usual Hall probe scanning technique, the sample is not magnetized as a whole before the scan, but locally by a small permanent magnet, which is fixed near the Hall probe, during the scanning process. The res

N. E. J. Bjerrum-Bohr

A previous study of the Kawai, Lewellen and Tye (KLT) relations between gravity and gauge theories, imposed by the relationship of closed and open strings, are here extended in the light of general relativity and Yang-Mills theory as effective field theories. We discuss the possibility of generalizing the traditional KLT mapping in this effective setting. A

Steen H. Hansen, Zoltan Haiman

A remarkable result of the Wilkinson Microwave Anisotropy Probe (WMAP) observations is that the universe was significantly reionized at large redshifts. The standard explanation is that massive stars formed early and reionized the universe around redshift z=17. Here we explore an alternative possibility, in which the universe was reionized in two steps. An e

Takahiro Tanaka

We analyze the weak gravity in the braneworld model proposed by Dvali-Gabadadze-Porrati, in which the unperturbed background spacetime is given by five dimensional Minkowski bulk with a brane which has the induced Einstein Hilbert term. This model has a critical length scale $r_c$. Naively, we expect that the four dimensional general relativity (4D GR) is ap

T. Padmanabhan, T. P. Singh

It is shown that linearized gravitational radiation confined in a cavity can achieve thermal equilibrium if the mean density of the radiation and the size of the cavity satisfy certain constraints.

G. Lamura, A. J. Purnell, L. F. Cohen, A. Andreone

The two tone intermodulation arising in MgB2 thin films deposited in-situ by planar magnetron sputtering on sapphire substrates is studied. Samples are characterised using an open-ended dielectric puck resonator operating at 8.8 GHz. The experimental results show that the third order products increase with the two-tone input power with a slope ranging betwee

T. Vuletic, B. Korin-Hamzic, S. Tomic, B. Gorshunov

The charge response in the spin chain/ladder compound Sr_14-xCa_xCu_24O_41 is characterized by DC resistivity, low-frequency dielectric spectroscopy and optical spectroscopy. We identify a phase transition below which a charge-density wave (CDW) develops in the ladder arrays. Calcium doping suppresses this phase with the transition temperature decreasing fro

Tommy Burch, Doug Toussaint

We use the non-relativistic expansion of QCD (NRQCD) on the lattice to study the lowest hybrid configuration contribution to the ground state of heavy S-wave mesons. Using lowest-order lattice NRQCD to create the heavy-quark propagators, we form a basis of ``unperturbed&#39;&#39; S-wave and hybrid states. We then apply the lowest-order coupling of the quark

L. F. Wei, Xiao Li, Xuedong Hu, Franco Nori

Ideal quantum algorithms usually assume that quantum computing is performed continuously by a sequence of unitary transformations. However, there always exist idle finite time intervals between consecutive operations in a realistic quantum computing process. During these delays, coherent &#34;errors&#34; will accumulate from the dynamical phases of the super

J. P. Ma, Z. G. Si

We study inclusive production of doubly heavy baryon at a $e^+e^-$ collider and at hadron colliders through fragmentation. We study the production by factorizing nonpertubative- and perturbative effects. In our approach the production can be thought as a two-step process: A pair of heavy quarks can be produced perturbatively and then the pair is transformed

H. Noh, J. Hwang

We consider instability of the Friedmann world model to the second-order in perturbations. We present the perturbed set of equations up to the second-order in the Friedmann background world model with general spatial curvature and the cosmological constant. We consider systems with the completely general imperfect fluids, the minimally coupled scalar fields,

Mark W. Paris

The eigenstates of a single massless Dirac particle confined in a linear potential are calculated exactly by direct solution of the Dirac equation. The electromagnetic structure functions are calculated from the Dirac wave functions of the ground and excited states of the particle by coupling to its conserved vector current. We obtain the longitudinal and tr

Tamara M. Davis, P. C. W. Davies, Charles H. Lineweaver

The generalized second law of thermodynamics states that entropy always increases when all event horizons are attributed with an entropy proportional to their area. We test the generalized second law by investigating the change in entropy when dust, radiation and black holes cross a cosmological event horizon. We generalize for flat, open and closed Friedman

Y. Sato, K. Kawara, L. L. Cowie, Y. Taniguchi

We present results of a deep mid-infrared survey in the SSA13 field with the Infrared Space Observatory (ISO). In order to probe the near-infrared light at high redshifts, we surveyed the field with the broad band LW2 (5-8.5um) filter of the mid-infrared camera ISOCAM. Adopting a highly redundant imaging strategy for the 23 hour observation and carefully tre