September 1999 arXiv papers — page 9

C. Di Bartolo, R. Gambini, J. Griego, J. Pullin

We present a quantization of the Hamiltonian and diffeomorphism constraint of canonical quantum gravity in the spin network representation. The novelty consists in considering a space of wavefunctions based on the Vassiliev knot invariants. The constraints are finite, well defined, and reproduce at the level of quantum commutators the Poisson algebra of cons

Abhas Mitra

The total spacetime manifold for a Schwarzschild black hole (BH) is described by the Kruskal coordinates u=u(r,t) and v=v(r,t), where r and t are the conventional Schwarzschild radial and time coordinates respectively. The relationship between r and t for a test particle moving on a radial or non-radial geodesic is well known. Similarly, the expression for t

R. J. Adler, A. S. Silbergleit

We review the derivation of the metric for a spinning body of any shape and composition using linearized general relativity theory, and also obtain the same metric using a transformation argument. The latter derivation makes it clear that the linearized metric contains only the Eddington $α$ and $γ$ parameters, so no new parameter is involved in frame-draggi

Francis C. Chu, Joseph Y. Halpern, Praveen Seshadri

We identify two unreasonable, though standard, assumptions made by database query optimizers that can adversely affect the quality of the chosen evaluation plans. One assumption is that it is enough to optimize for the expected case---that is, the case where various parameters (like available memory) take on their expected value. The other assumption is that

Francis C. Chu, Joseph Y. Halpern

We argue that the tools of decision theory need to be taken more seriously in the specification and analysis of systems. We illustrate this by considering a simple problem involving reliable communication, showing how considerations of utility and probability can be used to decide when it is worth sending heartbeat messages and, if they are sent, how often t

Joseph Y. Halpern, Richard A. Shore

Complete axiomatizations and exponential-time decision procedures are provided for reasoning about knowledge and common knowledge when there are infinitely many agents. The results show that reasoning about knowledge and common knowledge with infinitely many agents is no harder than when there are finitely many agents, provided that we can check the cardinal

Jaap-Henk Hoepman

We show that, contrary to common belief, Dijkstra's self-stabilizing mutual exclusion algorithm on a ring [Dij74,Dij82] also stabilizes when the number of states per node is one less than the number of nodes on the ring.

Michael Stone

By exploiting the mathematical analogy between the propagation of sound in a non-homogeneous potential flow and the propagation of a scalar field in a background gravitational field, various wave ``energy'' and wave ``momentum'' conservation laws are established in a systematic manner. In particular the acoustic energy conservation law due to

Michael Stone

I discuss the scattering of phonons by a vortex moving with respect to a superfluid condensate. This allows us to test the compatibility of the scattering-theory derivation of the Iordanskii force with the galilean invariance of the underlying fluid dynamics. In order to obtain the correct result we must retain $O(v_s^2)$ terms in the sound-wave equation, an

Amit Kr. Chattopadhyay, Jayanta K. Bhattacharjee

In the turbulent boundary layer above a flat plate, the velocity profile is known to have the form v=v_0[(1/κ) ln z + constant]. The distance from the wall in dimensionless units is z and v_0 is an uniquely defined velocity scale. The number κis universal and measurements over several decades have shown that it is nearly 0.42. We use a randomly stirred model

A. Buhot, A. Halperin

The extension elasticity of rod-coil mutliblock copolymers is analyzed for two experimentally accessible situations. In the quenched case, when the architecture is fixed by the synthesis, the force law is distinguished by a sharp change in the slope. In the annealed case, where interconversion between rod and coil states is possible, the resulting force law

Igor Loutsenko, Vyacheslav Spiridonov

Some direct relations between soliton solutions of integrable hierarchies and thermodynamical quantities of the Coulomb plasmas on the plane are revealed. We find that certain soliton solutions of the Kadomtsev-Petviashvili (KP) and B-type KP (BKP) hierarchies describe two-dimensional one or two component plasmas at special boundary conditions and fixed temp

V. Cataudella, G. De Filippis, G. Iadonisi

A new variational technique is developed to investigate the polaronic features of the Holstein Molecular Crystal Model. It is based on a linear superposition of Bloch states that describe large and small polaron wave functions. It is shown that this method provides a very good description of the regime characterized by intermediate values of the electron-pho

F. V. Kusmartsev, H. S. Dhillon

We describe a novel state of electrons and phonons arising in semiconductor superlattices (SSL) due to strong electron-phonon interactions. These states are characterized by a localization of phonons and a self-trapping or locking of electrons in one or several quantum wells due to an additional, deformational potential arising around these locking wells in

A. Bjelis, D. Zanchi, G. Montambaux

Taking into account both Pauli and orbital effects of external magnetic field we compute the mean field phase diagram for charge density waves in quasi-one-dimensional electronic systems. The magnetic field can cause transitions to CDW states with two types of the shifts of wave vector from its zero-field value. It can also stabilize the field-induced charge

Fabrizio Lillo, Rosario N. Mantegna

We select n stocks traded in the New York Stock Exchange and we form a statistical ensemble of daily stock returns for each of the k trading days of our database from the stock price time series. We analyze each ensemble of stock returns by extracting its first four central moments. We observe that these moments are fluctuating in time and are stochastic pro

Bosiljka Tadic

Two cellular automata models with directed mass flow and internal time scales are studied by numerical simulations. Relaxation rules are a combination of probabilistic critical height (probability of toppling $p$) and deterministic critical slope processes with internal correlation time $t_c$ equal to the avalanche lifetime, in Model A, and $t_c\equiv 1$, in

Marc Thilo Figge, Maxim Mostovoy, Jasper Knoester

We consider the Peierls instability due to the interaction of electrons with both acoustic and optical phonons. We suggest that such a transition takes place in carbon nanotubes with small radius. The topological excitations and the temperature dependence of the conductivity resulting from the electron-lattice interactions are considered.

Karim Bernardet, Ferenc Pazmandi, G. G. Batrouni

We propose a new picture of the renormalization group (RG) approach in the presence of disorder, which considers the RG trajectories of each random sample (realization) separately instead of the usual renormalization of the averaged free energy. The main consequence of the theory is that the average over randomness has to be taken after finding the critical

Siegfried Grossmann, Detlef Lohse

A systematic theory for the scaling of the Nusselt number $Nu$ and of the Reynolds number $Re$ in strong Rayleigh-Benard convection is suggested and shown to be compatible with recent experiments. It assumes a coherent large scale convection roll (``wind of turbulence'') and is based on the dynamical equations both in the bulk and in the boundary lay

D. W. Koerner, J. Davy Kirkpatrick, M. W. McElwain, N. R. Bonaventura

We present Keck near-infrared imaging of three binary L dwarf systems, all of which are likely to be sub-stellar. Two are lithium dwarfs, and a third exhibits an L7 spectral type, making it the coolest binary known to date. All have component flux ratios near 1 and projected physical separations between 5 and 10 AU, assuming distances of 18 to 26 pc from rec

C. M. Telesco, R. S. Fisher, R. K. Pina, R. F. Knacke

We present new 10.8 and 18.2 micron images of HR 4796A, a young A0V star that was recently discovered to have a spectacular, nearly edge-on, circumstellar disk prominent at ~20 microns (Jayawardhana et al. 1998; Koerner et al. 1998). These new images, obtained with OSCIR at Keck II, show that the disk's size at 10 microns is comparable to its size at 18

M. S. Yun, C. L. Carilli, R. Kawabe, Y. Tutui

We present sensitive radio continuum imaging at 1.4 GHz and 4.9 GHz of seven high redshift QSOs selected for having a 240 GHz continuum detection, which is thought to be thermal dust emission. We detect radio continuum emission from four of the sources: BRI 0952-0115, BR 1202-0725, LBQS 1230+1627B, and BRI 1335-0417. The radio source in BR 1202-0725 is resol

David W. Hogg, Michael A. Pahre, Kurt L. Adelberger, Roger Blandford

Detection and photometry of sources in the U_n, G, R, and K_s bands in a 9x9 arcmin^2 region of the sky, centered on the Hubble Deep Field, are described. The data permit construction of complete photometric catalogs to roughly U_n=25, G=26, R=25.5 and K_s=20 mag, and significant photometric measurements somewhat fainter. The galaxy number density is 1.3x10^

Sergei Nayakshin, Demosthenes Kazanas, Timothy R. Kallman

We study the X-ray illumination of an accretion disk. We relax the simplifying assumption of constant gas density used in most previous studies; instead we determine the density from hydrostatic balance. It is found that the thermal ionization instability prevents the illuminated gas from attaining temperatures at which the gas is unstable. In particular, th

J. S. B. Wyithe

The largest systematic uncertainty present in the analysis of gravitationally microlensed quasar light curves is that of the galactic transverse velocity. We describe a method for determining the transverse velocity as well as its application to published monitoring data of Q2237+0305 (Irwin et al. 1989; Corrigan et al. 1991; Ostensen et al 1995). We find th

Thomas Stanke, Mark J. McCaughrean, Hans Zinnecker

We report the discovery of a pair of large Herbig-Haro type structures roughly 10 arcminutes (1.3 pc) north-east and south-west of the source driving the well-known HH 46/47 Herbig-Haro jet in new deep emission-line images made using the Wide Field Imager on the ESO/MPG La Silla 2.2-m telescope. These new images suggest that the HH 46/47 outflow is much more

Jason D. Fiege, Ralph E. Pudritz

We present a new model of molecular cloud cores that originate from filamentary clouds that are threaded by helical magnetic fields. Only modest toroidal fields are required to produce elongated cores, with intrinsic axis ratios in the range 0.1 <= q <= 0.9 and mean projected axis ratios in the range 0.3 <= <p> <= 1. Thus many of our models are in good agree

K. Hurley, T. Strohmayer, P. Li, C. Kouveliotou

We present a 2 - 10 keV ASCA observation of the field around the soft gamma repeater SGR1627-41. A quiescent X-ray source was detected in this observation whose position was consistent both with that of a recently discovered BeppoSAX X-ray source and with the Interplanetary Network localization for this SGR. In 2 - 10 keV X-rays, the spectrum of the X-ray so

C. Travaglio, A. Burkert, D. Galli

We describe the basic features of a Monte Carlo model specifically designed to follow the inhomogenous chemical evolution of the Galactic halo, taking into account the effects of local enrichment and mixing of the halo gas, and with particular emphasis on elements like Eu produced by r-process nucleosynthesis. We compare our results with spectroscopic data f

K. M. Pontoppidan, T. Wiklind

We present a model to estimate the effect of differential magnification on the SED of high-z ULIRGs. It is found that the ratio of the high temperature component to the low temperature component can vary with up to a factor of ten with source position on very small angular scales ~0.01&#34;. This means that a correction for differential magnification is need

I. Marquez, F. Durret, R. M. Gonzalez Delgado, I. Marrero

We present infrared imaging data in the J and K&#39; bands obtained for 18 active spiral galaxies, together with 11 non active galaxies taken as a control sample. All of them were chosen to satisfy well defined isolation criteria so that the observed properties are not related to gravitational interaction. For each object we give: the image in the K&#39; ban

Carla Cacciari, Gisella Clementini, Fiorella Castelli, Fabrizio Melandri

We have applied the Baade-Wesselink method to two field RR Lyrae stars, i.e. SW And and RR Cet, and derived their distances and physical parameters. With respect to previous B-W analyses we have applied the following improvements: a) use of all sets of available data, after proper comparison for homogeneity and compatibility; b) use of the most recent and ac

Priyamvada Natarajan, Jean-Paul Kneib, Ian Smail

A synopsis of the recent results from our study of galaxy-galaxy lensing in clusters is presented. We have applied our analysis techniques to the sample of HST cluster-lenses that span a redshift range from redshift 0.18 to 0.58. We find that there is evidence that the total mass of a typical early-type cluster galaxy increases with redshift. For the lowest

Masaru Kajisawa, Toru Yamada

We investigated the color and morphology of optically selected galaxies in the region of clusters at z $\sim$ 1.2 near to the radio galaxy 3C 324 using archived data taken with the Hubble Space Telescope. The faint galaxies selected at the HST F702W band that contribute to the surface-density excess of the region have wide ranges of color, size, and morpholo

L. Pagani, J. Lequeux, D. Cesarsky, J. Donas

We present mid-IR images of a 15&#39;x15&#39; field in the south-west part of the Andromeda galaxy M 31 obtained with the ISOCAM camera on board ISO. We also present a 20&#34; resolution far-UV image of a larger field at 200 nm obtained with the balloon-borne telescope FOCA 1000. These images are compared with HI, CO(1-0) and Halpha maps. The mid-IR emission

K. Z. Stanek, A. Udalski

We investigate the influence of blending on the Cepheid distance scale. Blending leads to systematically low distances to galaxies observed with HST, and therefore to systematically high estimates of the Hubble constant H_0. We select a sample of 43 long-period, large-amplitude Cepheids in the Large Magellanic Cloud, from the catalog recently released by the

M. Catelan

The &#34;second-parameter effect&#34; is characterized by the existence of globular clusters (GCs) with similar metallicity [Fe/H] (the &#34;first parameter&#34;) but different horizontal-branch (HB) morphologies. One of the primary second-parameter candidates is cluster age. In the present paper, we address the following issue: &#34;Are the age differences

D. I. Makarov, I. D. Karachentsev

To reveal small galaxy groups in the Local Supercluster, a new approach is suggested which allows for individual properties of galaxies. The criterion is based on the assumption of closed motions of companions around the dominating group member within a zero velocity sphere. The criterion is applied to a sample of 6321 nearby galaxies with radial velocities

Paulo F. Bedaque, Martin J. Savage

A measurement of parity-violating spin-dependent gamma proton Compton scattering will provide a theoretically clean determination of the parity-violating pion-nucleon coupling constant $h_{πNN}^{(1)}$. We calculate the leading parity-violating amplitude arising from one-loop pion graphs in chiral perturbation theory. An asymmetry of ~5 10^{-8} is estimated f

Paul B. Slater

Duan, Giedke, Cirac and Zoller (quant-ph/9908056) and, independently, Simon (quant-ph/9909044) have recently found necessary and sufficient conditions for the separability (classical correlation) of the Gaussian two-party (continuous variable) states. Duan et al remark that their criterion is based on a &#34;much stronger bound&#34; on the total variance of

O. DeWolfe, D. Z. Freedman, S. S. Gubser, A. Karch

A method for obtaining solutions to the classical equations for scalars plus gravity in five dimensions is applied to some recent suggestions for brane-world phenomenology. The method involves only first order differential equations. It is inspired by gauged supergravity but does not require supersymmetry. Our first application is a full non-linear treatment

Andrzej Roslanowski, Saharon Shelah

The present paper has three themes. First, we continue the investigations started in Judah, Roslanowski and Shelah \math.LO/9310224 and Roslanowski and Shelah math.LO/9807172, math.LO/9703222, and we investigate the method of norms on possibilities in the context of ccc forcing notions, getting a number of constructions of nicely definable ccc forcings. The

Klaus Bering, Joel S. Rozowsky, Charles B. Thorn

We look back at early efforts to approximate the large N_c Feynman diagrams of QCD as very large fishnet diagrams. We consider more carefully the uniqueness of rules for discretizing P^+ and ix^+ which fix the fishnet model in the strong &#39;t Hooft coupling limit, and we offer some refinements that allow more of the crucial QCD interactions to be retained

Tsuguhiko Asakawa, Isao Kishimoto

We investigate the transformation from ordinary gauge field to noncommutative one which was introduced by N.Seiberg and E.Witten (hep-th/9908142). It is shown that the general transformation which is determined only by gauge equivalence has a path dependence in `θ-space&#39;. This ambiguity is negligible when we compare the ordinary Dirac-Born-Infeld action

G. Felder, J. Fr&#34;ohlich, J. Fuchs, C. Schweigert

We present a general construction of all correlation functions of a two-dimensional rational conformal field theory, for an arbitrary number of bulk and boundary fields and arbitrary topologies. The correlators are expressed in terms of Wilson graphs in a certain three-manifold, the connecting manifold. The amplitudes constructed this way can be shown to be

Oron Zachar, Alexei M. Tsvelik

We analyse a model of a one-dimensional electron gas interacting with an antiferromagnetic Heisenberg spin-1/2 chain via the spin exchange interactions. Using a solution at a special limit, we characterize the gapless modes of the spin gap fixed point at weak coupling $ J_{K}\ll J_{H},E_{F} $. we show that the only gapless pairing mode with divergent suscept

Salam Tawfiq, J. G. Koerner, Patrick J. O&#39;Donnell

Radiative decays of heavy baryons are analyzed within the Heavy Quark Symmetry (HQS). It is shown that employing the light-diquark symmetries, the number of electromagnetic couplings among S-wave and P-wave states as well as those between P-wave to S-wave transitions can be reduced significantly. Using this constituent quark model picture the phenomenologica

S. Sarkar, D. Pal, S. S. Banerjee, S. Ramakrishnan

The Peak Effect (PE) regime in a single crystal of Ca$_3$Rh$_4$Sn$_{13}$ has been investigated in detail via ac susceptibility as well as dc magnetization measurements. The PE region comprises two discontinuous first order like transitions, located near its onset and peak positions and reflects a stepwise fracturing of the flux line lattice (FLL). This scena

K. -V. Pham, M. Gabay, P. Lederer

We reconsider the spectrum of the Luttinger liquid (LL) usually understood in terms of phonons (density fluctuations), and within the context of bosonization we give an alternative representation in terms of fractional states. This allows to make contact with Bethe Ansatz which predicts similar fractional states. As an example we study the spinon operator in

C. W. J. Beenakker

This is a tutorial article based on a lecture delivered in June 1999 at the NATO Advanced Study Institute in Ankara. The phenomenon of Andreev reflection is introduced as the electronic analogue of optical phase-conjugation. In the optical problem, a disordered medium backed by a phase-conjugating mirror can become completely transparent. Yet, a disordered m

Vladimir P. Gerdt

In this paper we generalize the involutive methods and algorithms devised for polynomial ideals to differential ones generated by a finite set of linear differential polynomials in the differential polynomial ring over a zero characteristic differential field. Given a ranking of derivative terms and an involutive division, we formulate the involutivity condi

Vladimir P. Gerdt, Soso A. Gogilidze

In this paper we consider finite-dimensional constrained Hamiltonian systems of polynomial type. In order to compute the complete set of constraints and separate them into the first and second classes we apply the modern algorithmic methods of commutative algebra based on the use of Groebner bases. As it is shown, this makes the classical Dirac method fully

T. Room, U. Nagel, E. Lippmaa, H. Kageyama

Using far-infrared spectroscopy in magnetic fields up to 12T we have studied a two-dimensional dimer spin gap system SrCu_2(BO_3)_2. We found several infrared active modes in the dimerized state (below 10K) in the frequency range from 3 to 100cm^-1. The measured splitting from the ground state to the excited triplet M_S=0 sublevel is Delta_1=24.2cm^-1 and th

Kaname Toya, Kunihiko Fukushima, Yoshiyuki Kabashima, Masato Okada

We discuss the properties of equilibrium states in an autoassociative memory model storing hierarchically correlated patterns (hereafter, hierarchical patterns). We will show that symmetric mixed states (hereafter, mixed states) are bi-stable on the associative memory model storing the hierarchical patterns in a region of the ferromagnetic phase. This means

Eung Jin Chun, Sin Kyu Kang

We provide, in the R-parity violating supersymmetric standard model, a comprehensive analysis for sneutrino minimization from the one-loop effective scalar potential, and also for one-loop renormalized neutrino masses and mixing by calculating the effective neutrino mass matrix in the weak basis. Applying our results to theories with gauge mediated supersymm

Yuji Okawa

We consider the constraints on the effective Lagrangian of the rank-one gauge field on D-branes imposed by the equivalence between the description by ordinary gauge theory and that by non-commutative gauge theory in the presence of a constant B field. It is shown that we can consistently construct the two-derivative corrections to the Dirac-Born-Infeld Lagra

Imre Varga, Daniel Braun

We investigate the statistical properties of the eigenvalues and eigenvectors in a random matrix ensemble with $H_{ij}\sim |i-j|^{-μ}$. It is known that this model shows a localization-delocalization transition (LDT) as a function of the parameter $μ$. The model is critical at $μ=1$ and the eigenstates are multifractals. Based on numerical simulations we dem

Armin Uhlmann

We prove some new properties of fidelity (transition probability) and concurrence, the latter defined by straightforward extension of Wootters notation. Choose a conjugation and consider the dependence of fidelity or of concurrence on conjugated pairs of density operators. These functions turn out to be concave or convex roofs. Optimal decompositions are con

Alexander D. Popov

We introduce a new class of gauge field theories in any complex dimension, based on algebra-valued (p,q)-forms on complex n-manifolds. These theories are holomorphic analogs of the well-known Chern-Simons and BF topological theories defined on real manifolds. We introduce actions for different special holomorphic BF theories on complex, Kahler and Calabi-Yau

A. Kuiroukidis, D. B. Papadopoulos

We study the evolution of strings in the equatorial plane of a Kerr-Newmann black hole. Writting the equations of motion and the constraints resulting from Hamilton&#39;s principle, three classes of exact solutions are presented, for a closed string, encircling the black hole. They all depend on two arbitrary integration functions and two constants. A proces

S. Kumano, M. Miyama

We discuss the relation between the ratio of the proton-deuteron (pd) Drell-Yan cross section to the proton-proton (pp) one Δ_{(T)} σ_{pd}/2 Δ_{(T)} σ_{pp} and the flavor asymmetry in polarized light-antiquark distributions. Using a recent formalism of the polarized pd Drell-Yan process, we show that the difference between the pp and pd cross sections is val

Shoji Hashimoto

I review recent developments in lattice calculations of B decay matrix elements and other related quantities.

Masaaki Nakamura

Phase diagrams of the one-dimensional extended Hubbard model (including nearest-neighbor interaction $V$) at half- and quarter-filling are studied by observing level crossings of excitation spectra using the exact diagonalization. This method is based on the Tomonaga-Luttinger liquid theory including logarithmic corrections which stem from the renormalizatio

M. D. Albrow, J. -P. Beaulieu, J. A. R. Caldwell, D. L. DePoy

We present the PLANET photometric data set for \ob14, a high magnification ($A_{\rm max}\sim 16$) event alerted by the OGLE collaboration toward the Galactic bulge in 1998. The PLANET data set consists a total of 461 I-band and 139 $V-$band points, the majority of which was taken over a three month period. The median sampling interval during this period is a

V. S. Gerdjikov, E. G. Evstatiev, R. I. Ivanov

We propose a compact and explicit expression for the solutions of the complex Toda chains related to the classical series of simple Lie algebras g. The solutions are parametrized by a minimal set of scattering data for the corresponding Lax matrix. They are expressed as sums over the weight systems of the fundamental representations of g and are explicitly c

M. Horibe, K. Shigemoto

We clarify the structure of the Bazhanov-Baxter model of the 3-dim N-state integrable model. There are two essential points, i) the cubic symmetries, and ii) the spherical trigonometry parametrization, to understand the structure of this model. We propose two approaches to find a candidate as a solution of the tetrahedron equation, and we find a new solution

R. G. Unanyan, N. V. Vitanov, B. W. Shore, K. Bergmann

We present results from a study of the coherence properties of a system involving three discrete states coupled to each other by two-photon processes via a common continuum. This tripod linkage is an extension of the standard laser-induced continuum structure (LICS) which involves two discrete states and two lasers. We show that in the tripod scheme, there e

Jin Wang, H. M. Wiseman, Z. Ficek

It has been observed experimentally [H.R. Xia, C.Y. Ye, and S.Y. Zhu, Phys. Rev. Lett. {\bf 77}, 1032 (1996)] that quantum interference between two molecular transitions can lead to a suppression or enhancement of spontaneous emission. This is manifested in the fluorescent intensity as a function of the detuning of the driving field from the two-photon reson

Afshin Shafiee, Mehdi Golshani

Considering an extended type of Bohm&#39;s version of EPR thought experiment, we derive Bell&#39;s inequality for the case of factorizable contextual hidden variable theories which are consistent with the predictions of quantum theory. Usually factorizability is associated with non-contextuality. Here, we show that factorizability is consistent with contextu

P. R. C. Kent, M. D. Towler, R. J. Needs, G. Rajagopal

The thermodynamic stability of structural isomers of $\mathrm{C}_{24}$, $\mathrm{C}_{26}$, $\mathrm{C}_{28}$ and $\mathrm{C}_{32}$, including fullerenes, is studied using density functional and quantum Monte Carlo methods. The energetic ordering of the different isomers depends sensitively on the treatment of electron correlation. Fixed-node diffusion quantu

E. Knobloch, J. Moehlis

Different mechanisms believed to be responsible for the generation of bursts in hydrodynamical systems are reviewed and a new mechanism capable of generating regular or irregular bursts of large dynamic range near threshold is described. The new mechanism is present in the interaction between oscillatory modes of odd and even parity in systems of large but f

K. Sakamoto, M. Nakai, H. Kouno, A. Hasegawa

Based on quantum hadrodynamics with a finite cutoff, the effective masses of vector mesons(ω, ρ) in nuclear medium are calculated. We use a low-energy effective Lagrangian which is obtained by integrating high-energy quantum fluctuations. Although we use an artificial cutoff, the cutoff-dependence can be removed order by order. It is shown that there is a st

A. Sibirtsev, W. Cassing

We extract the antikaon potential from differential data on elastic $K^-A$ scattering within Glauber theory at an antikaon momentum of 800 MeV/c. The $K^-N$ cross section at densities up to 0.1 $fm^3$ is found to be close to the value given in free space $K^-p$ and $K^-n$ interactions (averaged over the number of protons and neutrons) whereas the ratio $α$ o

Yu. S. Lutostansky, M. V. Zverev

The instability of the $^{26}$O nucleus with respect to decay through the two-neutron channel is investigated. It is shown that this isotope, unobserved in the fragmentation experiments, can exist as a narrow resonance in the system $^{24}$O+2n. A role of deformation in formation of the neutron-drip line in the region $N\sim 20$ is discussed.

D. Knödler, H. Müther, P. Czerski

The contributions of short-range nucleon-nucleon (NN) correlations, various meson exchange current (MEC) terms and the influence of $Δ$ isobar excitations (isobaric currents, IC) on exclusive two-nucleon knockout reactions induced by electron scattering are investigated. The nuclear structure functions are evaluated for nuclear matter. Realistic NN interacti

K. Bennaceur, F. Nowacki, J. Okolowicz, M. Ploszajczak

We apply the realistic shell model which includes the coupling between many-particle (quasi-)bound states and the continuum of one-particle scattering states, called the Shell Model Embedded in the Continuum, to the spectroscopy of mirror nuclei: 17F and 17O, as well as to the description of low energy cross section (the astrophysical S-factor) for E1, E2 an

Serdar Kuyucak

Shape-phase transitions in mixed parity boson systems are studied using mean field theory. It is shown that without parity projection, shape transitions in mixed parity systems are very similar to those in positive parity systems, both requiring a finite interaction strength for the onset of deformation. The shape-phase diagram in mixed parity systems, howev

Horia Scutaru

The reformulation of Lieb&#39;s conjecture, in the frame of the harmonuic analysis on the SO(3) group, makes it evident that the exact value of the classical entropy of a pure quantum state, which belongs to the Hilbert space of a (2J+1)-dimensional, unitary, irreducible representation of the SO(3) group, depends only on the parameters which characterize the

Pablo Ramacher

Starting from Wigner&#39;s theory of elementary systems and following a recent approach of Schroer we define certain subspaces of localized wave functions in the underlying Hilbert space with the help of the theory of modular von-Neumann algebras of Tomita and Takesaki. We characterize the elements of these subspaces as boundary values of holomorphic functio

M. Alves

We discuss the two-dimensional dilaton gravity with a scalar field as the source matter where the coupling with the gravity is given, besides the minimal one, through an external field. This coupling generalizes the conformal anomaly in the same way as those found in recent literature, but with a diferent motivation. The modification to the Hawking radiation

Piet Termonia

We derive the invariant operators of the zero-form, the one-form, the two-form and the spinor from which the mass spectrum of Kaluza Klein of eleven-dimensional supergravity on AdS_4 x N^{010} can be derived by means of harmonic analysis. We calculate their eigenvalues for all representations of SU(3)xSO(3). We show that the information contained in these op

K. G. Selivanov

Recently the long-standing puzzle about counting the Witten index in N=1 supersymmetric gauge theories was resolved. The resolution was based on existence (for higher orthogonal $SO(N), N \geq 7$ and exceptional gauge groups) of flat connections on $T^{3}$ which have commuting holonomies but cannot be gauged to a Cartan torus. A number of papers has been pub

D. Blaschke, V. N. Pervushin, G. Roepke

We suggest that proper variables for the description of non-Abelian theories are those gauge invariant ones which keep the invariance of the winding number functional with respect to topologically nontrivial (large) gauge transformations. We present a model for these variables using the zero mode of the Gauss law constraint and investigate their physical con

Edmond L. Berger, Lionel E. Gordon, Michael Klasen

We calculate the transverse momentum distribution for the production of massive lepton-pairs in longitudinally polarized proton-proton reactions at collider energies within the context of perturbative quantum chromodynamics. For values of the transverse momentum Q_T greater than roughly half the pair mass Q, Q_T > Q/2, we show that the differential cross sec

M. Hirsch

Neutrinoless double beta ($\znbb$) decay violates lepton number; its absence stringently constrains the parameters of theories beyond the standard model in which the neutrino has a Majorana mass. R-parity violating weak-scale supersymmetry is a prominent example of such models. Double beta decay in supersymmetry with explicit bilinear R-parity breaking is di

K. B. Vijaya Kumar, Judith A. McGovern, Michael C. Birse

We present a calculation of the fourth-order (NLO) contribution to spin-dependent forward Compton scattering in heavy-baryon chiral perturbation theory. No low-energy constants, except for the anomalous magnetic moments of the nucleon, enter at this order. The fourth-order piece of the spin polarisability of the proton turns out to be almost twice the size o

M. Besancon, G. Moreau

A very short review on phenomenological aspects of supersymmetry with violated R-parity at e+e- colliders is given. We present specific examples of a search for supersymmetric particles with violating R-parity couplings at a 500 GeV~e+e- linear collider. The signal extraction, and the mass measurement in the case of a pair production of the lightest neutrali

Antonio Vairo

The heavy quarkonium static potential is discussed within the framework of potential NRQCD. Some quantitative statements are made in the kinematical situation $mv >> Λ_{\rm QCD}$ at the level of accuracy of the next-to-leading order in the multipole expansion.

M. V. Chizhov

The neutrino oscillation enhancement in the Earth-type medium mantle - core - mantle is discussed. It is noted that the total conversion is possible both for a resonant matter density and a nonresonant one. A useful parameterization, for the representation of the transition probability for neutrinos and antineutrinos in a single plot, is proposed.

E. Norrbin

In the hadroproduction of charm (or heavy flavours in general) in the context of string fragmentation, the pull of a beam remnant at the other end of a string may give a charm hadron more energy than the perturbatively produced one. The collapse of a low-mass string to a single hadron is the extreme case in this direction, and gives rise to asymmetries betwe

M. Steinhauser, T. Seidensticker

In this article two-loop QED corrections to the muon decay and corrections of order $α_s^2$ to the semileptonic decay of the bottom quark are considered. We compute the imaginary part of the four-loop diagrams contributing to the corresponding fermion propagator in the limit of small external momentum. The on-shell condition is obtained with the help of a co

S. Moretti, D. P. Roy

We investigate the charged Higgs boson signal at the LHC using its dominant production and decay modes with triple b-tagging, i.e. $tH^- \to t\bar tb \to b\bar bb W^+ W^-$, followed by leptonic decay of one W and hadronic decay of the other. We consider the continuum background from the associated production of $t\bar t$ with a b- or a light quark or gluon j

J. -P. Blaizot

This talk is a brief overview of the present status of our understanding of nucleus-nucleus collisions at high energy and the search for signals of the quark-gluon plasma.

S. Baek, P. Ko

In the minimal supersymmetric standard model (MSSM), the $μ-$parameter and the trilinear coupling $A_t$ may be generically complex and can affect various observables at B factories. Working in the effective SUSY models and imposing the edm constraints from Chang-Keung-Pilaftsis (CKP) mechanism, we find that (i) there is no new large phase shift in the $B^0 -

M. Besancon

An experimental search for signatures of Kaluza-Klein graviton states at the 500 GeV e+e- linear collider, in which the graviton states are produced in association with a photon, is presented. The study of the signal extraction is performed with the help of Monte Carlo simulations

S. M. Bilenky

The first papers on neutrino oscillations are shortly reviewed.

Y. Nakahara, M. Asakawa, T. Hatsuda

Using the maximum entropy method, spectral functions of the pseudo-scalar and vector mesons are extracted from lattice Monte Carlo data of the imaginary time Green&#39;s functions. The resonance and continuum structures as well as the ground state peaks are successfully obtained. Error analysis of the resultant spectral functions is also given on the basis o

G. Boix, D. Abbaneo

The properties of the amplitude method for $\Bs$ oscillation analyses are studied in detail. The world combination of measured amplitudes is converted into a likelihood profile as a function of oscillation frequency. A procedure is proposed to estimate the probability that the minimum observed is due to a statistical fluctuation. This method, applied to the

ALEPH Collaboration

The production rates of D*+-, Ds*+-, D+-, D0 / D0bar, Ds+, and Lambda_c in Z to ccbar decays are measured using the LEP I data sample recorded by the ALEPH detector. The fractional energy spectrum of the D*+- is well described as the sum of three contributions: charm hadronisation, b hadron decays and gluon splitting into a pair of heavy quarks. The probabil