July 2003 arXiv papers — page 11

Jacques Arnaud, Laurent Chusseau, Fabrice Philippe

Carnot established in 1824 that the efficiency $η_{C}$ of reversible engines operating between a hot bath at absolute temperature $T_{hot}$ and a cold bath at temperature $T_{cold}$ is equal to $1-T_{cold}/T_{hot}$. Carnot particularly considered air as a working fluid and small bath-temperature differences. Plugging into Carnot's expression modern exper

Bedangadas Mohanty

The transverse momentum spectra of the produced hadrons have been compared to a model which is based on the assumption that a nucleus-nucleus collision is a superposition of isotropically decaying thermal sources at a given freeze out temperature. The freeze-out temperature in nucleus-nucleus collisions is fixed from the inverse slope of the transverse momen

Naoki Tajima

We reanalyze the results of our extensive Hartree-Fock + BCS calculation from new points of view paying attention to the properties of unstable nuclei. The calculation has been done with the Skyrme SIII force for the ground and shape isomeric states of 1029 even-even nuclei ranging 2 <= Z <= 114. We also discuss the advantages of the employed three-dimension

Ghi R. Shin, Berndt Müller

We consider the evolution of a parton system which is formed in the central region just after a relativistic heavy ion collision. The parton consist of mostly gluons, minijets, which are produced by elastic scattering between constituent partons of the colliding nuclei. We assume the system can be described by a semi-classical Boltzmann transport equation, w

Tibor Tóth-Katona, James T. Gleeson

We report on the distribution spectra of the fluctations in the amount of power injected into a liquid crystal undergoing electroconvective flow. The probability distribution functions (PDFs) of the fluctuations as well as the magnitude of the fluctuations have been determined in a wide range of imposed stress both for `unconfined&#39; and `confined&#39; flo

A. E. Kovalsky, G. P. Pronko

In the present paper we describe the procedure of the Q-operators construction for the q-deformed model, described by the Lax operator, which is important to formulate the Bethe ansatz for the Sin-Gordon model. This Lax operator can also be considered as some massless limit of the Lax operator of SG model. We constructed two R-operators which are the univers

Dominique Delande, Jakub Zakrzewski

Statistics of tunneling rates in the presence of chaotic classical dynamics is discussed on a realistic example: a hydrogen atom placed in parallel uniform static electric and magnetic fields, where tunneling is followed by ionization along the fields direction. Depending on the magnetic quantum number, one may observe either a standard Porter-Thomas distrib

Sarika Jalan, R. E. Amritkar, Chin-Kun Hu

We study self-organized (s-) and driven (d-) synchronization in coupled map networks for some simple networks, namely two and three node networks and their natural generalization to globally coupled and complete bipartite networks. We use both linear stability analysis and Lyapunov function approach for this study and determine stability conditions for synch

A. A. Stolin, P. P. Kulish, E. V. Damaskinsky

A method to construct the universal twist element using the constant quasiclassical unitary matrix solution of the Yang - Baxter equation is proposed. The method is applied to few known $R$ -matrices, corresponding to Lie (super) algebras of rank one.

Steven J. Benson, Todd S. Munson

Discretizations of infinite-dimensional variational inequalities lead to linear and nonlinear complementarity problems with many degrees of freedom. To solve these problems in a parallel computing environment, we propose two active-set methods that solve only one linear system of equations per iteration. The linear solver, preconditioner, and matrix structur

Peter Jorgensen

This paper shows among other things that over a non-commutative Koszul algebra, high truncations of finitely generated graded modules have linear free resolutions.

Alexander Barchechat

In this thesis, we use normal surface theory to understand certain properties of minimal triangulations of compact orientable 3-manifolds. We describe the collapsing process of normal 2-spheres and disks. Using some geometrical constructions to take connected sums of triangulated 3-manifolds, we obtain the following result: given a minimal triangulation of a

Gavin Brown, Alessio Corti, Francesco Zucconi

We study the geography and birational geometry of 3-fold conic bundles over P^2 and cubic del Pezzo fibrations over P^1. We discuss many explicit examples and raise several open questions. This paper was submitted to the proceedings of the &#34;Fano conference&#34; held in Torino in October 2002.

Montserrat Teixidor i Bigas

Let E be a generic vector bundle of rank r and degree d on a generic curve of genus g. If r&#39;d-rd&#39;=r&#39;(r-r&#39;)(g-1), the number of subbundles E&#39; of E of rank r&#39; and degree d&#39; is finite. We present a new method to compute the number of such E&#39; that consists in degenerating the curve to a reducible curve. We obtain very explicit for

Montserrat Teixidor i Bigas

Denote by B^k_{2,K} the locus of vector bundles of rank two and canonical determinant. We show that for a generic curve of genus g, B^k_{2,K} is non-empty if g is sufficiently large.

M. C. Lopes Filho, H. J. Nussenzveig Lopes, G. V. Planas

In [1], T. Clopeau, A. Mikelić, and R. Robert studied the inviscid limit of the 2D incompressible Navier-Stokes equations in a bounded domain subject to Navier friction-type boundary conditions. They proved that the inviscid limit satisfies the incompressible Euler equations and their result ultimately includes flows generated by bounded initial vorticities.

Kei-ichi Watanabe, Ken-ichi Yoshida

In this paper, we investigate a lower bound (say $s_{HK}(p,d)$) on Hilbert-Kunz multiplicities for non-regular unmixed local rings of Krull dimension $d$ with characteristic $p>0$. Especially, we focus three-dimensional local rings. In fact, as a main result, we will prove that $s_{HK}(p,3) = 4/3$ and that a three-dimensional complete local ring of Hilbert-K

Albert Chau, Oliver C. Schnuerer

We study stability of non-compact gradient Kaehler-Ricci flow solitons with positive holomorphic bisectional curvature. Our main result is that any compactly supported perturbation and appropriately decaying perturbations of the Kaehler potential of the soliton will converge to the original soliton under Kaehler-Ricci flow as time tends to infinity. To obtai

Adam Sikora

For an abstract self-adjoint operator $L$ and a local operator $A$ we study the boundedness of the Riesz transform $AL^{-α}$ on $L^p$ for some $α>0$. A very simple proof of the obtained result is based on the finite speed propagation property for the solution of the corresponding wave equation. We also discuss the relation between the Gaussian bounds and the

A. J. Roberts

The long term aim is to use modern dynamical systems theory to derive discretisations of noisy, dissipative partial differential equations. As a first step we here consider a small domain and apply stochastic centre manifold techniques to derive a model. The approach automatically parametrises subgrid scale processes induced by spatially distributed stochast

Jian Song

The global holomorphic α-invariant introduced by Tian is closely related with the study in the existence of Kahler-Einstein metric. We apply the result of Tian, Lu and Zelditch on polarized Kahler metrics to approximate plurisubharmonic functions and compute the α-invariant of toric Fano manifolds.

Davide Gaiotto, Nissan Itzhaki, Leonardo Rastelli

We propose a Boundary Conformal Field Theory description of hole states in the c=1 matrix model.

Falk Bruckmann, Michael Engelhardt

The manner in which continuum center vortices generate topological charge density is elucidated using an explicit example. The example vortex world-surface contains one lone self-intersection point, which contributes a quantum 1/2 to the topological charge. On the other hand, the surface in question is orientable and thus must carry global topological charge

Anais Smailagic, Euro Spallucci

We formulate Feynman path integral on a non commutative plane using coherent states. The propagator for a free particle exhibits UV cut-off induced by the parameter of non commutativity.

B. Kleihaus, J. Kunz, Ya. Shnir

We present a new class of static axially symmetric solutions of SU(2) Yang-Mills-Higgs theory, where the Higgs field vanishes on rings centered around the symmetry axis. Associating a magnetic dipole moment with each Higgs vortex ring, the dipole moments add for solutions in the trivial topological sector, whereas they cancel for magnetically charged solutio

Christian Brouder

To set up a self-consistent quantum field theory of degenerate systems, the unperturbed state should be described by a density matrix instead of a pure state. This increases the combinatorial complexity of the many-body equations. Hopf algebraic techniques are used to deal with this complexity and show that the Schwinger-Dyson equations are modified in a non

Stanislaw D. Glazek, Jaroslaw Mlynik

Accuracy of a relativistic weak-coupling expansion procedure for solving the Hamiltonian bound-state eigenvalue problem in theories with asymptotic freedom is measured using a well-known matrix model. The model is exactly soluble and simple enough to study the method up to sixth order in the expansion. The procedure is found in this case to match the precisi

Minoru Eto, Nobuhito Maru, Norisuke Sakai

The recently found non-BPS multi-wall configurations in the N=1 supergravity in four dimensions is shown to have no tachyonic scalar fluctuations without additional stabilization mechanisms. Mass of radion (lightest massive fluctuation) is found to be proportional to $Lambda {\rm e}^{-πΛR/2}$, where $Λ$ is the inverse width of the wall and $ R$ is the radius

Willem T. H. van Oers

In understanding the world of matter, the introduction of symmetry principles following experimentation or using the predictive power of symmetry principles to guide experimentation is most profound. The conservation of energy, linear momentum, angular momentum, charge, and CPT involve fundamental symmetries. All other conservation laws are valid within a re

E. G. Adelberger, B. R. Heckel, A. E. Nelson

We review recent experimental tests of the gravitational inverse-square law and the wide variety of theoretical considerations that suggest the law may break down in experimentally accessible regions.

A. V. Nesterenko

In the framework of the analytic approach to Quantum Chromodynamics a new model for the strong running coupling has recently been developed. Its underlying idea is to impose the analyticity requirement on the perturbative expansion of the renormalization group $β$ function for restoring the correct analytic properties of the latter. The proposed model posses

A. Daleo, C. A. Garcia Canal, R. Sassot

We discuss the order α_s^2 gluon initiated QCD corrections to one particle inclusive deep inelastic processes. We focus in the NLO evolution kernels relevant for the non homogeneous QCD scale dependence of these cross sections and factorization.

R. N. Boyd, T. Rauscher, S. D. Reitzner, P. Vogel

Lead perchlorate, part of the OMNIS supernova neutrino detector, contains two nuclei, 208Pb and 35Cl, that might be used to study nucleon decay. Both would produce signatures that will make them especially useful for studying less-well-studied neutron decay modes, e.g., those in which only neutrinos are emitted.

Masakiyo Kitazawa, Tomoi Koide, Teiji Kunihiro, Yukio Nemoto

In the preceding paper(Prog.Theor.Phys.108(2002)929 or hep-ph/0207255), we have shown that the critical line of the first order chiral transition of QCD can have two endpoints. In this addendum, we elucidate the mechanism to realize the two-endpoint structure in the QCD phase diagram and argue the robustness for the appearance of such an interesting phase st

Gustavo C. Branco

We describe some of the extensions of the SM, including models with spontaneous CP violation, where New Physics relevant for CP violation may arise. It is emphasized that the SM predicts a series of exact relations among various measurable quantities, such as moduli of CKM matrix elements and rephasing invariant phases. These exact relations provide a string

Sidi Cherkawi Benzahra, Benjamin F. Bayman

In this work we calculate the lifetime of quarkonium moving with velocity $v$ through a quark gluon plasma at temperature $T$. We also investigate the stability of heavy mesons with respect to the effects of color charge screening. An explicit, configuration-space potential is found for the screened interaction between the quarks constituting the meson. We s

T. Kamon, R. Arnowitt, B. Dutta, V. Khotilovich

A feasibility study of a 500-GeV linear collider is presented for mSUGRA models in co-annihilation region. We find an active mask is critical to suppress $e^+ e^- \to e^+ e^- τ^+ τ^-$ events to probe the models.

Alex G. Dias, V. Pleitez, M. D. Tonasse

We show that in 3-3-1 models it is possible to implement an extremely flat scalar potential, i.e., a zero contribution to the cosmological constant, and still having realistic values for the masses of the scalar Higgs fields. Besides, when loop corrections are considered they impose constraints over heavy particles masses (exotic quarks and extra vector boso

Douglas R. Bergman

The HiRes Collaboration has recently announced preliminary measurements of the energy spectrum of ultra-high energy cosmic rays (UHECR), as seen in monocular analyses from each of the two HiRes sites. This spectrum is consistent with the existence of the GZK cutoff, as well other aspects of the energy loss processes that cause the GZK cutoff. Based on the an

J. Z. Bai et al

Results are presented on $J/ψ$ radiative decays to $K^+K^-$ and $K^0_SK^0_S$ based on a sample of 58M $J/ψ$ events taken with the BES II detector. A partial wave analysis is carried out using the relativistic covariant tensor amplitude method in the 1-2 GeV mass range. There is conspicuous production due to the $f&#39;_2(1525)$ and $f_0(1710)$. The latter pe

Lino Miramonti

The main goal of the Borexino detector, in its final phase of construction in the Gran Sasso underground laboratory, is the direct observation and measurement of the low energy component of neutrinos coming from the Sun. The unique low energy sensitivity and ultra-low background bring new capabilities to attack problems in neutrino physiscs other than solar

Daisuke Ida, Yuki Uchida

The Einstein-Maxwell equations in D-dimensions admitting (D-3) commuting Killing vector fields have been investigated. The existence of the electric, magnetic and twist potentials have been proved. The system is formulated as the harmonic map coupled to gravity on three-dimensional base space generalizing the Ernst system in the four-dimensional stationary E

Hussein Gibbins, Rajkumar Buyya

The notion of grid computing has gained an increasing popularity recently as a realistic solution to many of our large-scale data storage and processing needs. It enables the sharing, selection and aggregation of resources geographically distributed across collaborative organisations. Now more and more people are beginning to embrace grid computing and thus

L. H. Yu, D. Natelson

A streamlined technique for the electrochemical fabrication of metal nanojunctions (MNJs) between lithographically defined electrodes is presented. The first low-temperature transport measurements in such structures reveal suppression of the conductance near zero-bias. The size of the zero-bias anomaly (ZBA) depends strongly on the fabrication electrochemist

Nicola Scafetta, Bruce J. West

The multiresolution diffusion entropy analysis is used to evaluate the stochastic information left in a time series after systematic removal of certain non-stationarities. This method allows us to establish whether the identified patterns are sufficient to capture all relevant information contained in a time series. If they do not, the method suggests the ne

Nicola Scafetta, Timothy Imholt, J. A. Roberts, Bruce J. West

We study the fractal properties of the distances between consecutive primes. The distance sequence is found to be well described by a non-stationary exponential probability distribution. We propose an intensity-expansion method to treat this non-stationarity and we find that the statistics underlying the distance between consecutive primes is Gaussian and th

G. Drazer, H. Auradou, J. Koplik, J. P. Hulin

The evolution and spatial structure of displacement fronts in fractures with self-affine rough walls are studied by numerical simulations. The fractures are open and the two faces are identical but shifted along their mean plane, either parallel or perpendicular to the flow. An initially flat front advected by the flow is progressively distorted into a self-

Federico Corberi, Eugenio Lippiello, Marco Zannetti

In this paper we investigate the relation between the scaling properties of the linear response function $R(t,s)$, of the thermoremanent magnetization (TRM) and of the zero field cooled magnetization (ZFC) in the context of phase ordering kinetics. We explain why the retrival of the scaling properties of $R(t,s)$ from those of TRM and ZFC is not trivial. Pre

Carsten Honerkamp, Manfred Salmhofer

We review magnetic and superconducting instabilities in the t-t&#39; Hubbard model on the two-dimensional square lattice as obtained with functional one-loop renormalization group techniques. Special emphasis is put on ferromagnetic and triplet superconducting tendencies that could be relevant to the triplet superconductor Sr2RuO4.

Wonkee Kim, F. Marsiglio, J. P. Carbotte

The low temperature thermal conductivity of a d-wave superconductor is considered for arbitrary strength of the impurity potential. A random distribution of vortices is included within the usual semiclassical approach. The vortex-quasiparticle scattering is accounted for phenomenologically, in addition to impurity scattering. Application of the theory to rec

Pawel Machnikowski, Lucjan Jacak

We study the kinetics of confined carrier-phonon system in a quantum dot under fast optical driving and discuss the resulting limitations to fast coherent control over the quantum state in such systems.

D. H. E. Gross

It is shown that the recently introduced singularities of the microcanonical entropy like &#34;microcanonical phase transitions&#34;, and exotic pattern of the microcanonical caloric curve T(E) like multi-valuednes or the appearance of &#34;dinosaur&#39;s necks&#34; are inconsistent with Boltzmann&#39;s fundamental definition of entropy S=ln[W(E)] for a syst

Arnab Chatterjee

The login time distribution in e-mail servers are studied. The distribution seems to be decaying in a scale-free manner with a decay exponent lying between 1.2 and 2.2, varying from server to server. A simple mean-field theory shows that this distribution has a decay exponent 2.

Sergei Sergeenkov

A unified approach for description of the anomalous critical current enhancement in dislocated, deoxygenated, and particle irradiated superconductors is proposed based on a novel concept of &#34;active pinning&#34; (pinning via external fields modified intrinsic Josephson junctions) and existence of various competitive forces affecting a rather delicate bala

Victor A. Gopar, Dietmar Weinmann, Rodolfo A. Jalabert, Robert L. Stamps

We study the effect of a domain wall on the electronic transport in ferromagnetic quantum wires. Due to the transverse confinement, conduction channels arise. In the presence of a domain wall, spin up and spin down electrons in these channels become coupled. For very short domain walls or at high longitudinal kinetic energy, this coupling is weak, leads to v

B. Hamprecht, W. Janke, H. Kleinert

We set up and solve a recursion relation for all even moments of a two-dimensional stiff polymer (Porod-Kratky wormlike chain) and determine from these moments a simple analytic expression for the end-to-end distribution at all persistence lengths.

A. D. Armour, M. P. Blencowe, Y. Zhang

We analyze the dynamics of a nano-mechanical resonator coupled to a single-electron transistor (SET) in the regime where the resonator behaves classically. A master equation is derived describing the dynamics of the coupled system which is then used to obtain equations of motion for the average charge state of the SET and the average position of the resonato

Gen&#39;ya Sakurai, Yoshio Kuramoto

Microscopic investigation is performed for intersite multipolar interactions in the orbitally degenerate Anderson lattice, with CeB$_6$ taken as an exemplary target. In addition to the $f^0$ intermediate state, $f^2$ Hund&#39;s-rule ground states are included as intermediate states for the interactions. The conduction-band states are taken as plane waves and

S. C. Wi, J. -S. Kang, J. H. Kim, S. -B. Cho

Electronic structures of Zn$_{1-x}$Co$_x$O have been investigated using photoemission spectroscopy (PES) and x-ray absorption spectroscopy (XAS). The Co 3d states are found to lie near the top of the O $2p$ valence band, with a peak around $\sim 3$ eV binding energy. The Co $2p$ XAS spectrum provides evidence that the Co ions in Zn$_{1-x}$Co$_{x}$O are in th

J. -S. Kang, S. C. Wi, J. H. Kim, K. A. McEwen

The electronic structures of the localized $5f$ systems UTSn (T=Ni, Pd) have been investigated using photoemission spectroscopy (PES). The extracted U $5f$ PES spectra of UTSn (T=Ni, Pd) exhibit a broad peak centered at $\sim 0.3$ eV below $\rm E_F$ with rather small spectral weight near $\rm E_F$ (N$_f$($\rm E_F$)). The small N$_f$($\rm E_F$) in UTSn is fou

Tomasz Dobrowolski

The purpose of this report is presentation of the main modifications of the standard Kibble-Zurek formalism caused by the existence of the unperfections in the system. We know that the distribution of kinks created during a second order phase transition in pure systems is determined solely by the correlation length at freeze-out time. The correlation length

D. -N. Peligrad, A. Dulcic, M. Mehring

Critical fluctuations have been studied in the microwave conductivity of Bi_2Sr_2CaCu_2O_(8+δ), Bi_2Sr_2Ca_2Cu_3O_(10+delta), and YBa_2Cu_3O_(7-delta) thin films above T_c. It is found that a consistent analysis of the real and imaginary parts of the fluctuation conductivity can be achieved only if an appropriate wavevector or energy cutoff in the fluctuatio

Chris J. Hamer, Weihong Zheng, Rajiv R. P. Singh

We develop a linked cluster method to calculate the spectral weights of many-particle excitations at zero temperature. The dynamical structure factor is expressed as a sum of exclusive structure factors, each representing contributions from a given set of excited states. A linked cluster technique to obtain high order series expansions for these quantities i

Jinfeng Liao, Pengfei Zhuang

A general analysis on Fermion pairing at finite temperature and density between different species with mismatched Fermi surfaces is presented. Very different from the temperature effect of BCS phase, the recently found breached pairing phase resulted from density difference of the two species lies in a region with calabash-like shape in the $T-μ$ plane, and

A. B. Harris, T. Yildirim, A. Aharony, O. Entin-Wohlman

The five-band Hubbard model for a $d$ band with one electron per site is a model which has very interesting properties when the relevant ions are located at sites with high (e. g. cubic) symmetry. In that case, if the crystal field splitting is large one may consider excitations confined to the lowest threefold degenerate $t_{2g}$ orbital states. When the el

Onuttom Narayan, Abhishek Dhar

For sound waves impinging on a one-dimensional medium, we show that nonlinearity can lead to nonreciprocal transmission, without dissipation or broken time reversal invariance. Placing quasi-monochromatic filters at the ends of the nonlinear medium, nonreciprocity can be obtained without the generation of higher harmonics outside the medium. Remarkably, in t

Philip B. Allen, W. Garber, L. Angelani

Lennard-Jones glasses (made on a computer by quenching from liquid state coordinates) are studied in harmonic approximation. Vibrational eigenfrequencies and eigenvectors are found by exact diagonalization for models with periodic boundaries and N=(500, 2048, and 6980) atoms. We analyze the density of states, mobility edge, and bond-stretching character of t

Yugui Yao, L. Kleinman, A. H. MacDonald, Jairo Sinova

We perform a first principles calculation of the anomalous Hall effect in ferromagnetic bcc Fe. Our theory identifies an intrinsic contribution to the anomalous Hall conductivity and relates it to the k-space Berry phase of occupied Bloch states. The theory is able to account for both dc and magneto-optical Hall conductivities with no adjustable parameters.

Rene Messina

The adsorption of highly charged flexible polycations and polyanions on a charged cylindrical substrate is investigated by means of Monte Carlo (MC) simulations. A detailed structural study, including monomer and fluid charge distributions, is provided. The influence of a short range attraction between the polycations and the negatively charged substrate is

Frantisek Slanina, Petr Chvosta

We formulate and solve a model of dynamical arrest in colloids. A particle is coupled to the bath of statistically identical particles. The dynamics is described by Langevin equation with stochastic external force described by telegraphic noise. The interaction with the bath is taken into account self-consistently through the back-reaction mechanism. Dynamic

Eric Gaidos, Christopher Koresko

We obtained low resolution (R = 100) mid-infrared (8-13 micron wavelengths) spectra of 8 nearby young main sequence stars with the Keck 1 telescope and Long-Wavelength Spectrometer (LWS) to search for 10 micron silicate (Si-O stretch) emission from circumstellar dust. No stars exhibited readily apparent emission: Spectra were then analyzed by least-squares f

T. L. Aldcroft, A. Siemiginowska, M. Elvis, S. Mathur

The red quasar 3C 212 (z=1.049) is one of the most distant and most luminous AGN which has shown evidence of an X-ray warm absorber. In order to further investigate this unusual quasar, we used Chandra/ACIS-S to observe 3C 212 for 19.5 ksec, resulting in a net detection of ~4000 counts. The Chandra data confirm the presence of an excess absorbing column N_H

Jordi Miralda-Escude

The Dark Age is the period between the time when the cosmic microwave background was emitted and the time when the evolution of structure in the universe led to the gravitational collapse of objects in which the first stars were formed. The period of reionization started with the ionizing light from the first stars, and it ended when all the atoms in the int

Ken Ebisawa, Piotr Zycki, Aya Kubota, Tsunefumi Mizuno

Ultra-luminous Compact X-ray Sources (ULXs) in nearby spiral galaxies and Galactic superluminal jet sources share the common spectral characteristic that they have unusually high disk temperatures which cannot be explained in the framework of the standard optically thick accretion disk in the Schwarzschild metric. On the other hand, the standard accretion di

A. De Angelis, O. Mansutti, R. Pain

The mixing of the photon with a hypothetical sterile paraphotonic state would have consequences on the cosmological propagation of photons. Observations of gamma-rays from active galactic nuclei in GLAST and MAGIC will open a new domain in the search for such a phenomenon.

Chaitra A. Narayan, Chanda J. Jog

The stellar disk in a spiral galaxy is believed to be truncated physically because the disk surface brightness is observed to fall faster than that for an exponential in the outer, faint regions. We review the literature associated with this phenomenon and find that a number of recent observations contradict the truncation picture. Hence we question the very

Paola Andreani, Luigi Spinoglio, Matthew A. Malkan

Averaged spectral energy distributions (SEDs) of active and starburst galaxies from the 12 micron sample in the Local Universe and Quasars, from an optically selected sample at a mean redshift <z>=0.7, are built from optical/near-IR/far-IR (IRAS & ISO) photometric observations. These SEDs are then used to predict at various redshifts the number of Seyfert ty

R. Iaria, T. Di Salvo, N. R. Robba, L. Burderi

We report on the results from two BeppoSAX observations of the Z source GX 349+2 performed in February 2001 and covering the broad energy range 0.12-200 keV. The light curve obtained from these observations shows a large flaring activity, the count rate varying from ~130 to ~260 counts/s, indicating that the source was in the flaring branch during these obse

Karen Knierman, Sarah Gallagher, Jane Charlton, Sally Hunsberger

Using V and I images obtained with WFPC2/HST, we investigate compact stellar structures within tidal tails. Six regions of tidal debris in the four classic ``Toomre Sequence&#39;&#39; mergers: NGC 4038/39 (``Antennae&#39;&#39;), NGC 3256, NGC 3921, and NGC 7252 (``Atoms for Peace&#39;&#39;) have been studied in order to explore how the star formation depends

M. F. Bietenholz, N. Bartel, M. P. Rupen

We present two sequences of VLBI images of SN1993J in M81, with 24 images at 8.4 GHz and 19 images at 5.0 GHz, These sequences, from 50 d to ~9 yr after shock breakout, show the evolution of the expanding radio shell of an exploded star in detail. The images are all phase-referenced to the stable reference point of the core of M81, allowing us to display the

T. Erben, J. M. Miralles, D. Clowe, M. Schirmer

We perform a weak lensing analysis on a previously reported dark-lens candidate on STIS Parallel data (Miralles et al. 2002). New VLT-data indicate that the reported signal originates from a small number of galaxies tangentially aligned towards the center of the STIS field but no signature for an extended mass distribution is found. We argue that we should b

Martin G. Haehnelt

The hierarchical build-up of galactic bulges should lead to the build-up of present-day supermassive black holes by a mixture of gas accretion and merging of supermassive black holes. The tight relation between black hole mass and stellar velocity dispersion is thereby a strong argument that the supermassive black holes in merging galactic bulges do indeed m

Martin G. Haehnelt

The tight correlation between black hole mass and velocity dispersion of galactic bulges is strong evidence that the formation of galaxies and supermassive black holes are closely linked. I review the modeling of the joint formation of galaxies and their central supermassive black holes in the context of the hierarchical structure formation paradigm.

A. Georgakakis, A. M. Hopkins, M. Sullivan, J. Afonso

In this paper we use a 50ks XMM-Newton pointing overlapping with the Phoenix Deep Survey, a homogeneous radio survey reaching muJy sensitivities, to explore the X-ray properties and the evolution of star-forming galaxies. UV, optical and NIR photometry is available and is used to estimate photometric redshifts and spectral types for radio sources brighter th

Gabriela Canalizo, Claire Max, David Whysong, Robert Antonucci

We present Keck II adaptive optics near infrared imaging and spectroscopic observations of the central regions of the powerful radio galaxy Cygnus A. The 0.05&#34; resolution images clearly show an unresolved nucleus between two spectacular ionization/scattering cones. We report the discovery of a relatively bright (K&#39;~19) secondary point source 0.4&#34;

Adam J. Burgasser, Michael W. McElwain, J. Davy Kirkpatrick

We present the discovery of three new Southern Hemisphere T dwarfs identified in the Two Micron All Sky Survey. These objects, 2MASS 0348-6022, 2MASS 0516-0445, and 2MASS 2228-4310, have classifications T7, T5.5, and T6.5, respectively. Using linear absolute magnitude/spectral type relations derived from T dwarfs with measured parallaxes, we estimate spectro

Y. Yao, S. Nan Zhang, X. L. Zhang, Y. X. Feng

With excellent angular resolution, good energy resolution and broad energy band, the Chandra ACIS is the best instrument for studying the X-ray halos around some galactic X-ray point sources caused by the dust scattering of X-rays in the interstellar medium. However, the direct images of bright sources obtained with ACIS usually suffer from severe pile-up. M

P. M. Gehring, K. Ohwada, G. Shirane

We report measurements of the neutron diffuse scattering from a single crystal of the relaxor ferroelectric Pb(Zn_1/3Nb_2/3)O_3 doped with 8% PbTiO_3 (PZN-8%PT) for temperatures 100 K < T < 530 K and electric fields 0 kV/cm < E < 10 kV/cm. The diffuse scattering is strongly suppressed transverse to the (003) Bragg peak at 400 K for E = 2 kV/cm applied along

Michael Freedman, Chetan Nayak, Kirill Shtengel, Kevin Walker

We describe a class of parity- and time-reversal-invariant topological states of matter which can arise in correlated electron systems in 2+1-dimensions. These states are characterized by particle-like excitations exhibiting exotic braiding statistics. $P$ and $T$ invariance are maintained by a `doubling&#39; of the low-energy degrees of freedom which occurs

Yunkyu Bang, M. J. Graf, A. V. Balatsky

We calculated the nuclear spin-lattice relaxation rate $1/T_1$ for the D+iD superconducting state with impurities. We found that small amount of unitary impurities quickly produces the residual density of states inside the gap. As a result, the T-linear behavior in 1/T$_1$ is observed at low temperatures. Our results show that the D+iD pairing symmetry of th

Amr El-Zant, Isaac Shlosman

A substantial fraction of disk galaxies is double-barred. We analyze the dynamical stability of such nested bar systems by means of Liapunov exponents,by fixing a generic model and varying the inner (secondary) bar mass. We show that there exists a critical mass below which the secondary bar cannot sustain its own orbital structure, and above which it progre

Zoltan Nagy

The production of the three jets in hadron-hardon collision is the first more complex process which allow us to define a branch of variables in order to do more precise measurement of the strong coupling and the parton distribution function of the proton. This process is also suitable for studying the geometrical properties of the hadronic final state at had

Edward V. Shuryak, Ismail Zahed

We argue that although at asymptotically high temperatures the QGP in bulk behaves as a gas of weakly interacting quasiparticles (modulo long-range magnetism), at temperatures up to few times the critical temperature $T_c$ it displays different properties. If the running of the QCD coupling constant continues in the Coulomb phase till the screening length sc

Jonathan Oppenheim

The spectrum of multiple level transitions of the quantum black hole is considered, and the line widths calculated. Initial evidence is found for these higher order transitions in the spectrum of quasinormal modes for Schwarzschild and Kerr black holes, further bolstering the idea that there exists a correspondence principle between quantum transitions and c

Arvind, David Collins

We discuss the ensemble version of the Deutsch-Jozsa (DJ) algorithm which attempts to provide a &#34;scalable&#34; implementation on an expectation-value NMR quantum computer. We show that this ensemble implementation of the DJ algorithm is at best as efficient as the classical random algorithm. As soon as any attempt is made to classify all possible functio

P. C. de Holanda, A. Yu. Smirnov

The Homestake result is about ~ 2 σlower than the Ar-production rate, Q_{Ar}, predicted by the LMA MSW solution of the solar neutrino problem. Also there is no apparent upturn of the energy spectrum (R \equiv N_{obs}/N_{SSM}) at low energies in SNO and Super-Kamiokande. Both these facts can be explained if a light, Δm^2_{01} ~ (0.2 - 2) \cdot 10^{-5} eV^2, s

Iakovos Androulidakis

Due to a result by Mackenzie, extensions of transitive Lie groupoids are equivalent to certain Lie groupoids which admit an action of a Lie group. This paper is a treatment of the equivariant connection theory and holonomy of such groupoids, and shows that such connections give rise to the transition data necessary for the classification of their respective

E. Prada, F. Sols

We investigate theoretically the simultaneous tunneling of two electrons from a superconductor into a normal metal at low temperatures and voltages. Such an emission process is shown to be equivalent to the Andreev reflection of an incident hole. We obtain a local tunneling Hamiltonian that permits to investigate transport through interfaces of arbitrary geo

Stephane Fay, Jean-Pierre Luminet

Starting from an anisotropic flat cosmological model(Bianchi type $I$), we show that conditions leading to isotropisation fall into 3 classes, respectively 1, 2, 3. We look for necessary conditions such that a Bianchi type $I$ model reaches a stable isotropic state due to the presence of several massive scalar fields minimally coupled to the metric with a pe

P. Kanti, I. Olasagasti, K. Tamvakis

We analyze further the possibility of obtaining localized black hole solutions in the framework of Randall-Sundrum-type brane-world models. We consider black hole line-elements analytic at the horizon, namely, generalizations of the Painleve and Vaidya metrics, which are taken to have a decaying dependence of the horizon on the extra dimension. These backgro