November 2003 arXiv papers — page 7

J. Szczytko, L. Kappei, J. Berney, F. Morier-Genoud

We present the results of a detailed time resolved luminescence study carried out on a very high quality InGaAs quantum well sample where the contributions at the energy of the exciton and at the band edge can be clearly separated. We perform this experiment with a spectral resolution and a sensitivity of the set-up allowing to keep the observation of these

Matthias Paessens, Gunter M. Schuetz

The variance of the local density of the pair contact process with diffusion (PCPD) is investigated in a bosonic description. At the critical point of the absorbing phase transition (where the average particle number remains constant) it is shown that for lattice dimension d>2 the variance exhibits a phase transition: For high enough diffusion constants, it

A. C. Papageorgopoulos, H. Wang, C. Guerrero, N. Garcia

In this study we present a new method of measuring magnetostriction with an atomic force microscope adapted for the application magnetic fields. The experiment allows us to visualise, in an elegant and educational way how the lateral magnetoelastic shape changes take place on the sample surface when a magnetic field is applied. We have, furthermore, used thi

Pawel Sobkowicz

The work investigates the influence of leader's strategy on opinion formation in artificial networked societies. The strength of the social influence is assumed to be dictated by distance from one agent to another, as well as individual strengths of the agents. The leader is assumed to have much greater resources, which allows him to tune the way he infl

V. P. S. Awana, M. A. Ansari, Rashmi Nigam, Anurag Gupta

LaBaCaCu3O7 (La:1113) and NdBaCaCu3O7 (Nd:1113) compounds are synthesized by solid state reaction route. Both compounds crystallize in tetragonal structure. Four probe resistivity measurements showed that superconducting transition temperature (Tc) is 73 K and 41 K respectively for La:1113 and Nd:1113 compounds. Considering the fact that for RE:123 (REBa2Cu3

M. A. Ansari, V. P. S. Awana, Anurag Gupta, R. B. Saxena

Samples of YBa2-xSrxCu3O7-d (x = 0.0, 0.50, 1.0) series were synthesized by solid-state reaction and first annealed in flowing O2 gas. All samples crystallized in orthorhombic structure, where orthorhombic distortion was found to decrease with an increase in x. Four probe resistivity measurements showed that superconducting transition temperature (Tc) decrea

Sourin Das, Sumathi Rao, Diptiman Sen

We examine the effect of interactions between the electrons on the conductances of some systems of quantum wires with different geometries. The systems include a wire with a stub in the middle, a wire containing a ring which can enclose a magnetic flux, and a system of four wires which are connected in the middle through a fifth wire. Each of the wires is ta

Takafumi Kita

A theoretical study is performed on the entropy $S_{\rm s}$ and the spin susceptibility $χ_{\rm s}$ near the upper critical field $H_{c2}$ of s-wave type-II superconductors with arbitrary impurity concentrations. The changes of these quantities through $H_{c2}$ may be expressed as $[S_{\rm s}(T,B)-S_{\rm s}(T,0)]/[S_{\rm n}(T)-S_{\rm s}(T,0)]=1-α_{S}(1-B/H_{

T. Nakane, T. Mochiku, H. Kito, M. Nagao

The metastable phase of an yttrium sesquicarbide compound, which was vary recently reported as a new superconductive phase with a Tc value of 18 K, was prepared under high pressure from the nominal composition of Y2C3 and Y2C2.9B0.1 in order to investigate this phase. We have succeeded in reproduction, and in the transport measurement for this 18-K phase. It

V. Ravi Chandra

Generalising recent studies on the sawtooth lattice, a two-spin variant of the model is considered. Numerical studies of the energy spectra and the relevant spin correlations in the problem are presented. Perturbation theory analysis of the model explaining some of the features of the numerical data is put forward and the spin wave spectra of the model corre

T. Mukaiyama, J. R. Abo-Shaeer, K. Xu, J. K. Chin

The dissociation of ultracold molecules is studied by ramping an external magnetic field through a Feshbach resonance. The observed dissociation energy shows non-linear dependence on the ramp speed and directly yields the strength of the atom-molecule coupling. In addition, inelastic molecule-molecule and molecule-atom collisions are characterized.

Y. Zhao, M. Ionescu, J. Horvat, S. X. Dou

Two types of MgB2 films were prepared by pulsed laser deposition (PLD) with in situ and ex situ annealing processes respectively. Significant differences in properties between the two types of films were found. The ex situ MgB2 film has a Tc of 38.1K, while the in situ film has a depressed Tc of 34.5K. The resistivity at 40K for the in situ film is larger th

Chenggang Zhou, Mona Berciu

We perform first principles numerical simulations to investigate resistance fluctuations in mesoscopic samples, near the transition between consecutive Quantum Hall plateaus. We use six-terminal geometry and sample sizes similar to those of real devices. The Hall and longitudinal resistances extracted from the generalized Landauer formula reproduce all the e

C. M. Varma

The cure to the $\ell=1$ Landau-Pomeranchuk (L-P) instabilities in translationally invariant fermions is shown to be a state with an anisotropic gap at the fermi-surface. For higher $\ell$ and for fermions on a lattice, general criteria for long wavelength instabilities and their cure are found in terms of the derivatives of the single particle self-energy w

R. J. Radwanski, Z. Ropka

The orbital and spin moment of the Co2+ ion in CoO has been calculated within the quasi-atomic approach with taking into account the intra-atomic spin-orbit coupling and crystal field interactions. The orbital moment of 1.38 m_B amounts at 0 K, in the magnetically-ordered state, to more than 34% of the total moment 4.02 m_B and yields the L/S ratio of 1.04,

R. J. Radwanski, Z. Ropka

We have shown that the observed large reduction of the effective moment and the drastic violation of the Curie-Weiss law in Na2V3O7 (Phys. Rev. Lett. 90 (2003) 167202) is caused by conventional crystal-field interactions and the intra-atomic spin-orbit coupling of the V4+ ion. The fine discrete electronic structure of the 3d1 configuration with the weakly-ma

Michael Hermele, Matthew P. A. Fisher, Leon Balents

We study the S=1/2 Heisenberg antiferromagnet on the pyrochlore lattice in the limit of strong easy-axis exchange anisotropy. We find, using only standard techniques of degenerate perturbation theory, that the model has a U(1) gauge symmetry generated by certain local rotations about the z-axis in spin space. Upon addition of an extra local interaction in th

Yasushi Suto

Simulations of large-scale structure in the universe have played a vital role in observational cosmology since 1980's in particular. Their important role will definitely continue to be true in the 21st century. Rather the requirements for simulations in the precision cosmology era will become more progressively demanding; they are supposed to fill the mi

Robert M. Salow, Thomas S. Statler

We present new dynamical models of weakly self-gravitating, finite dispersion eccentric stellar disks around central black holes for the double nucleus of M31. The disk is fixed in a frame rotating at constant precession speed, and is populated by stars on quasi-periodic orbits whose parents are numerically integrated periodic orbits in the total potential.

J. T. Stocke, B. A. Keeney, A. D. Lewis, H. W. Epps

We use the Karachentseva (1973) ``Catalogue of Very Isolated Galaxies'' to investigate a candidate list of >100 very isolated early-type galaxies. Broad-band imaging and low resolution spectroscopy are available for a large fraction of these candidates and result in a sample of 102 very isolated early-type galaxies, including 65 ellipticals and 37 S0

David A. Thilker, Robert Braun, Rene A. M. Walterbos, Edvige Corbelli

Green Bank Telescope (GBT) 21cm observations have revealed a faint, yet extensive HI cloud population surrounding the Andromeda Galaxy (M31). The newfound objects are likely analogs to the high-velocity HI clouds (HVCs) seen around the Milky Way. At least 20 discrete features are detected within 50 kpc of the M31 disk, with radial velocities that are compara

Edward A. Baltz, Lam Hui

The microlensing interpretation of the optical afterglow of GRB 000301C seems naively surprising, since a simple estimate of the stellar microlensing rate gives less than one in four hundred for a flat Omega_Lambda=0.7 cosmology, whereas one event was seen in about thirty afterglows. Considering baryonic MACHOs making up half of the baryons in the universe,

S. B. Kraemer, G. J. Ferland, J. R. Gabel

We examine the effects of low-temperature, or $Δ$$n = 0$, dielectronic recombination (DR) on the ionization balance of the Fe M-Shell (Fe IX through Fe XVI). Since $Δ$$n = 0$ rates are not available for these ions, we have derived estimates based on the existing rates for the first four ionization states of the CNO sequence and newly calculated rates for L-s

L. V. E. Koopmans, A. G. de Bruyn

We present a kinematic model of the neutral-hydrogen in the spiral galaxy of the lens system PKS1830-211, based on a Multi Element Radio-Linked Interferometer (MERLIN) 1.4-GHz radio map and the integrated and redshifted 21-cm hydrogen absorption-line profile as measured with the Westerbork Synthesis Radio Telescope (WSRT). Degeneracies in the models do not a

A. Chalabaev, E. le Coarer, P. Rabou, Y. Magnard

The GraF instrument using a Fabry-Perot interferometer cross-dispersed with a grating was one of the first integral-field and long-slit spectrographs built for and used with an adaptive optics system. We describe its concept, design, optimal observational procedures and the measured performances. The instrument was used in 1997-2001 at the ESO 3.6 m telescop

N. R. Deacon, N. C. Hambly

In this paper we present surveys of two open clusters using photometry and accurate astrometry from the SuperCOSMOS microdensitometer. These use plates taken by the Palomar Oschin Schmidt Telescope giving a wide field ($5^{\circ}$ from the cluster centre in both cases), accurate positions and a long time baseline for the proper motions. Distribution function

Y. I. Izotov, G. Stasinska, N. G. Guseva, T. X. Thuan

We have derived element abundances in 310 emission-line galaxies from the Early Data Release of the Sloan Digital Sky Survey (SDSS) for which the [O {\sc iii}] 4363 emission line was detected, allowing abundance determination by direct methods. We found no extremely metal-deficient galaxy (Z<Zsun/12), probably as a consequence of selection effects in the SDS

Patrick B. Hall, Damien Hutsemekers

The outflow in SDSS J030000.56+004828.0 has the highest low-ionization metal-line column density yet reported for a broad absorption line quasar. The absorption from different ions is also segregated as a function of velocity in a way that can only be explained by a disk wind outflow. Furthermore, the presence of the such large column densities of gas at the

P. G. Jonker, R. Wijnands, M. van der Klis

We present the analysis of a 35 ksec long Chandra observation of the neutron star soft X-ray transient (SXT) SAX J1810.8-2609. We detect three sources in the field of view. The position of one of them is consistent with the location of the ROSAT error circle of SAX J1810.8-2609. The accurate Chandra position of that source coincides with the position of the

Vincenzo F. Cardone

It is well known that the surface brightness of elliptical galaxies and of bulges of spiral galaxies is best fitted by the Sersic r^{1/n} profile. It is thus interesting to explore the lensing properties of the Sersic model because of its wide range of applicability. To this aim, we evaluate the lensing potential, the deflection angle, the time delay between

Thomas Rauch

AA Dor is an eclipsing, close, post common-envelope binary consisting of a sdOB primary star and an unseen secondary with an extraordinary small mass - formally a brown dwarf. The brown dwarf may have been a former planet which survived a common envelope phase and has even gained mass. A recent determination of the components&#39; masses from results of NLTE

D. de Martino, G. Matt, T. Belloni, F. Haberl

We present broad-band (0.1--90keV) spectral and temporal properties of the three Intermediate Polars, RE0751+144 (PQ Gem), RXJ0558.0+5353 (V405Aur) and RXJ1712.6-2414 (V2400 Oph) based on simultaneous soft and hard X-ray observations with the BeppoSAX satellite. The analysis of their spectra over the wide energy range of BeppoSAX instruments allows us to ide

E. Belsole, G. W. Pratt, J-L. Sauvageot, H. Bourdin

We present results from the XMM-Newton observation of the binary cluster A1750 at z = 0.086. We have performed a detailed study of the surface brightness, temperature and entropy distribution and confirm that the two main clusters of the system (A1750 N and A1750 C) have just started to interact. From the temperature distribution, we calculate that they are

Frank Lenzen, Sabine Schindler, Otmar Scherzer

We present an algorithm developed particularly to detect gravitationally lensed arcs in clusters of galaxies. This algorithm is suited for automated surveys as well as individual arc detections. New methods are used for image smoothing and source detection. The smoothing is performed by so-called anisotropic diffusion, which maintains the shape of the arcs a

Katsuya Okoshi, Masahiro Nagashima, Naoteru Gouda, Satoshi Yoshioka

We investigate chemical enrichment in Damped Lyman alpha (DLA) systems in the hierarchical structure formation scenario using a semi-analytic model of galaxy formation. The model developed by Nagashima, Totani, Gouda and Yoshii takes into account various selection effects on high-redshift galaxies and can show fundamental observational properties of galaxies

Panayotis Boumis, Myfanwy Bryce

We present deep Halpha+[N II] CCD images of selected new Planetary Nebulae (PNe) discovered through an [O III] 5007 A emission line survey in the Galactic Bulge region with l > 0 deg. In total, we detected more than 200 objects, including 45 new PNe. Deep Halpha+[N II] CCD images as well as low resolution spectra were obtained for the new PNe in order to stu

Tahir Yaqoob, Urmila Padmanabhan

We report on the results of 18 observations of the core, or peak, of the Fe K emission line at $\sim 6.4$ keV in 15 Seyfert I galaxies using the {\it Chandra} High Energy Grating (HEG). These data afford the highest precision measurements of the peak energy of the Fe K line, and the highest spectral resolution measurements of the width of the core of the lin

Ryo Yamazaki, Daisuke Yonetoku, Takashi Nakamura

Using a simple off-axis jet model of GRBs, we can reproduce the observed unusual properties of the prompt emission of GRB980425, such as the extremely low isotropic equivalent gamma-ray energy, the low peak energy, the high fluence ratio, and the long spectral lag when the jet with the standard energy of ~10^{51} ergs and the opening half-angle of Δθ=~10-30

Ryo Yamazaki, Kunihito Ioka, Takashi Nakamura

The <V/Vmax> of the cosmological X-ray flashes detected by WFC/BeppoSAX is calculated theoretically in a simple jet model. The total emission energy from the jet is assumed to be constant. We find that if the jet opening half-angle is smaller than 0.03 radian, off-axis emission from sources at z<~4 can be seen. The theoretical <V/Vmax> is less than 0.4, whic

Andrew Gould

By extending the constant-acceleration analysis of Smith, Mao, & Paczynski to include jerk, I show that microlens parallax measurements are subject to a four-fold discrete degeneracy. The new degeneracy is characterized by a projected velocity \tilde v_j = -(3/4)\cscβ_\ec(\cos^2ψ\sin^2β_\ec+\sin^2ψ)^{3/2}v_earth, where β_\ec is the ecliptic latitude, ψis the

Douglas P. Finkbeiner

We investigate the nature of the diffuse Galactic emission in the Wilkinson Microwave Anisotropy Probe (WMAP) temperature anisotropy data. Substantial dust-correlated emission is observed at all WMAP frequencies, far exceeding the expected thermal dust emission in the lowest frequency channels (23, 33, 41 GHz). The WMAP team (Bennett et al.) interpret this e

Yuval Grossman, Subhendu Rakshit

We study neutrino masses and mixing in R-parity violating supersymmetric models with generic soft supersymmetry breaking terms. Neutrinos acquire masses from various sources: Tree level neutrino--neutralino mixing and loop effects proportional to bilinear and/or trilinear R-parity violating parameters. Each of these contributions is controlled by different p

James M. Cline, Sangyong Jeon, Guy D. Moore

It has been suggested that a scalar field with negative kinetic energy, or ``ghost,&#39;&#39; could be the source of the observed late-time cosmological acceleration. Naively, such theories should be ruled out by the catastrophic quantum instability of the vacuum. We derive phenomenological bounds on the Lorentz-violating ultraviolet cutoff Lambda which must

Ivette Fuentes-Guridi, Florian Girelli, Etera R. Livine

We present a scheme to study non-abelian adiabatic holonomies for open Markovian systems. As an application of our framework, we analyze the robustness of holonomic quantum computation against decoherence. We pinpoint the sources of error that must be corrected to achieve a geometric implementation of quantum computation completely resilient to Markovian dec

C. Anastasiou, Kirill Melnikov, Frank Petriello

We propose a new method of computing real emission contributions to hard QCD processes. Our approach uses sector decomposition of the exclusive final-state phase space to enable extraction of all singularities of the real emission matrix elements before integration over any kinematic variable. The exact kinematics of the real emission process are preserved i

V. R. Shaginyan

The behavior of the electronic system of heavy fermion metals is considered. We show that there exist at least two main types of the behavior when the system is nearby a quantum critical point which can be identified as the fermion condensation quantum phase transition (FCQPT). We show that the first type is represented by the behavior of a highly correlated

B. Aubert

We present measurements of branching fractions and charge asymmetries in $B$-meson decays to $ρ^+ π^{0}$, $ρ^{0}π^+$ and $ρ^0π^0$. The data sample comprises $89 \times 10^6$ $Υ(4S) \to B\bar{B}$ decays collected with the $BaBar$ detector at the PEP-II asymmetric-energy $B$ Factory at SLAC. We find the charge-averaged branching fractions ${\cal B}(B^{+}\to ρ^

Yongluo Cao, Stefano Luzzatto, Isabel Rios

We consider some general classes of random dynamical systems and show that a priori very weak nonuniform hyperbolicity conditions actually imply uniform hyperbolicity.

Mark Alford, Chris Kouvaris, Krishna Rajagopal

In neutral cold quark matter that is sufficiently dense that the strange quark mass M_s is unimportant, all nine quarks (three colors; three flavors) pair in a color-flavor locked (CFL) pattern, and all fermionic quasiparticles have a gap. We argue that as a function of decreasing quark chemical potential mu or increasing M_s, there is a quantum phase transi

D. L. Pagan, M. E. Gracheva, J. D. Gunton

Grand canonical Monte Carlo simulations are used to explore the metastable fluid-fluid coexistence curve of the modified Lennard-Jones model of globular proteins of ten Wolde and Frenkel (Science, v277, 1975 (1997)). Using both mixed-field finite-size scaling and histogram reweighting methods, the joint distribution of density and energy fluctuations is anal

G. E. Bruno

Experiment NA57 has collected high statistics, high purity samples of $K^0_s$, $Λ$, $Ξ$ and $Ω$ produced in Pb-Pb collisions at 158 $A$ GeV/$c$. In this paper we present a study of the transverse mass spectra of these particles for a sample of events corresponding to about the most central 55% of the inelastic Pb-Pb cross section. We analyse the transverse m

J. B. Bell, M. S. Day, C. A. Rendleman, S. E. Woosley

Planar flames are intrinsically unstable in open domains due to the thermal expansion across the burning front--the Landau-Darrieus instability. This instability leads to wrinkling and growth of the flame surface, and corresponding acceleration of the flame, until it is stabilized by cusp formation. We look at the Landau-Darrieus instability for C/O thermonu

R. A. Arndt, W. J. Briscoe, I. I. Strakovsky, R. L. Workman

We present results from a comprehensive partial-wave analysis of pi+-p elastic scattering and charge-exchange data, covering the region from threshold to 2.1 GeV in the lab pion kinetic energy, employing a coupled-channel formalism to simultaneously fit pi-p\toηn data to 0.8 GeV. Our main result, solution FA02, utilizes a complete set of forward and fixed-t

M. B. Barbaro, J. A. Caballero, T. W. Donnelly, C. Maieron

Highly inelastic electron scattering is analyzed within the context of the unified relativistic approach previously considered in the case of quasielastic kinematics. Inelastic relativistic Fermi gas modeling that includes the complete inelastic spectrum - resonant, non-resonant and Deep Inelastic Scattering - is elaborated and compared with experimental dat

N. C. Santos, G. Israelian, M. Mayor

We present stellar parameters and metallicities, obtained from a detailed spectroscopic analysis, for a large sample of 98 stars known to be orbited by planetary mass companions (almost all known targets), as well as for a volume-limited sample of 41 stars not known to host any planet. For most of the stars the stellar parameters are revised versions of the

Sergei A. Klioner

A relativistic definition of the physically adequate proper reference system of a test observer is suggested within the framework of the PPN formalism. According to the nomenclature accepted within the GAIA project this reference system is called Center-of-Mass Reference System (CoMRS). The interrelation between the suggested definition of the CoMRS and the

N. Kamakura, Y. Takata, T. Tokushima, Y. Harada

Soft X-ray Angle-Resolved Photoemission Spectroscopy is applied to study in-plane band dispersions of Nickel as a function of probing depth. Photon energies between 190 and 780 eV were used to effectively probe up to 3-7 layers. The results show layer dependent band dispersion of the Delta_2 minority-spin band which crosses the Fermi level in 3 or more layer

Masashi Hamanaka

We discuss commuting flows and conservation laws for Lax hierarchies on noncommutative spaces in the framework of the Sato theory. On commutative spaces, the Sato theory has revealed essential aspects of the integrability for wide class of soliton equations which are derived from the Lax hierarchies in terms of pseudo-differential operators. Noncommutative e

Matias Zaldarriaga, Steven Furlanetto, Lars Hernquist

The relatively large Thomson optical depth, tau_e, inferred recently from the WMAP observations suggests that the Universe was reionized in a more complex manner than previously believed. However, the value of tau_e provides only an integral constraint on the history of reionization and, by itself, cannot be used to determine the nature of the sources respon

C. Rubano, P. Scudellaro, E. Piedipalumbo, S. Capozziello

We show that a general, exact cosmological solution, where dynamics of scalar field is assigned by an exponential potential, fulfils all the issues of dark energy approach, both from a theoretical point of view and in comparison with available observational data. Moreover, tracking conditions are discussed, with a new treatment of the well known condition $Γ

Shan-Gui Zhou, Hans-Christian Pauli

We use a light cone harmonic oscillator model to study S wave meson spectra, namely the pseudoscalar and vector mesons. The model Hamiltonian is a mass squared operator consisting of a central potential (a harmonic oscillator potential) from which a hyperfine interaction is derived. The hyperfine interaction is responsible for the splitting in the pseudoscal

S. De Curtis, D. Dominici, J. R. Pelaez

We identify the goldstino fields that give mass to the Kaluza Klein modes of five dimensional supergravity, when supersymmetry breaking is induced by brane effects. We then proof the four dimensional Equivalence Theorem that, in renormalizable gauges, allows for the replacement of Kaluza Klein modes of helicity $\pm1/2$ gravitinos in terms of goldstinos. Fin

V. Ravindran, J. Smith, W. L. van Neerven

We present the full next-to-next-to-leading order (NNLO) coefficient functions for the polarized cross section $dΔσ/dQ$ for the Drell-Yan process $p + p\to l^+l^- + &#39;X&#39;$. Here $&#39;X&#39;$ denotes any inclusive hadronic state and $Q$ represents the invariant mass of the lepton pair. All QCD partonic subprocesses have been included provided the lepto

Antonio Vairo

In this brief review, I summarize the current theoretical knowledge of heavy quarkonium inclusive decays, with emphasis on recent progress made in the framework of QCD effective field theories. In appendix, I list the imaginary parts of the matching coefficients of the dimension 6 and dimension 8 NRQCD four-fermion operators as presently known.

Yu. S. Kalashnikova

The problem of whether it is possible to distinguish composite from elementary particles is studied in the framework of Weinberg&#39;s approach. The possibility to extend this approach to the case of unstable particles in the presence of inelastic channels is considered. The interplay between the low-energy scattering data and the admixture of a bare state i

Bernard de Wit, Henning Samtleben, Mario Trigiante

Using a recently proposed group-theoretical approach, we explore novel gaugings of maximal supergravity in four dimensions with gauge group embeddings that can be generated by fluxes of IIB string theory. The corresponding potentials are positive without stationary points. Some allow domain wall solutions which can be elevated to ten dimensions. Appropriate

Eric Ricard

We prove that the von Neumann algebras generated by $n$ $q$-Gaussian elements, are factors for $n\ge 2$.

Gentaro Watanabe, Katsuhiko Sato, Kenji Yasuoka, Toshikazu Ebisuzaki

Structure of hot dense matter at subnuclear densities is investigated by quantum molecular dynamics (QMD) simulations. We analyze nucleon distributions and nuclear shapes using two-point correlation functions and Minkowski functionals to determine the phase-separation line and to classify the phase of nuclear matter in terms of the nuclear structure. Obtaine

Liliana Arrachea, Luca Capriotti, Sandro Sorella

We study the spin-1/2 Heisenberg model in a lattice that interpolates between the triangular and the kagome lattices. The exchange interaction along the bonds of the kagome lattice is J, and the one along the bonds connecting kagome and non-kagome sites is J&#39;, so that J&#39;=J corresponds to the triangular limit and J&#39;=0 to the kagome one. We use var

Mikhail A. Ivanov, Juergen G. Korner, Pietro Santorelli

We calculate the amplitudes and the cross sections of the charm dissociation processes J/ψπ=> D \bar D, D* \bar D, D \bar D*, D* \bar D* within a relativistic constituent quark model. We consistently account for the contributions coming from both the box and triangle diagrams that contribute to the dissociation processes. The cross section is dominated by th

Boguslaw Hajduk, Aleksy Tralle

We prove that there exist diffeomorphisms of tori, supported in a disc, which are not isotopic to symplectomorphisms with respect to any symplectic structure. This yields a partial negative answer to a question of Benson and Gordon about the existence of symplectic structures on tori with exotic differential structure.

Eduardo Pereira, Jose M. G. Martinho, Mario N. Berberan-Santos

Photon trajectories in incoherent radiation trapping for Doppler, Lorentz and Voigt line shapes under complete frequency redistribution are shown to be Levy flights. The jump length (r) distributions display characteristic long tails. For the Lorentz line shape, the asymptotic form is a strict power-law r^{-3/2} while for Doppler the asymptotic is r^{-2} (ln

M. Marklund, P. K. Shukla, G. Brodin, L. Stenflo

The nonlinear interaction, due to quantum electrodynamical (QED) effects, between two electromagnetic pulses and a radiation gas is investigated. It is found that the governing equations admit both modulational and filamentational instabilities. The instability growth rates are derived, and the results are discussed.

Daisuke Ida, Kin-ya Oda, Seong Chan Park

We consider the production and decay of TeV sized black holes. After discussing evaluation of the production cross section of higher dimensional rotating black holes and black rings, the master equation for general spin-$s$ fields confined on brane world is derived. For five-dimensional (Randall-Sundrum) black holes, we obtain analytic formulae for the greyb

Andreas Engel, Rémi Monasson, Alexander K. Hartmann

We show that large deviation properties of Erdös-Rényi random graphs can be derived from the free energy of the $q$-state Potts model of statistical mechanics. More precisely the Legendre transform of the Potts free energy with respect to $\ln q$ is related to the component generating function of the graph ensemble. This generalizes the well-known mapping be

Zhi-Gang Wang, Lin Li, Tao Huang

In this article, we calculate the nonfactorizable soft contributions in the $B \to η_c K, χ_{c0} K$ decays with the light cone QCD sum rules approach. Our results show that the nonfactorizable corrections from the soft gluon exchanges in the decay $B \to η_c K$ are of $(15-30)%$ and should not be neglected. As for the decay $B \to χ_{c0} K$, the factorizable

Esther M. Hu, Lennox L. Cowie, Peter Capak, Richard G. McMahon

We report results of a deep wide-field narrowband survey for redshift z~5.7 Ly alpha emitters carried out with SuprimeCam on Subaru 8.3-m telescope. Deep narrowband imaging of the SSA22 field through a 120 A bandpass filter centered at 8150 A was combined with deep multicolor RIz' SuprimeCam broadband imaging, and BVRZ imaging taken with CFHT's CFH12K camera

Adrian Dumitru, Yoshitaka Hatta, Jonathan Lenaghan, Kostas Orginos

We discuss how to extract renormalized from bare Polyakov loops in SU(N) lattice gauge theories at nonzero temperature in four spacetime dimensions. Single loops in an irreducible representation are multiplicatively renormalized without mixing, through a renormalization constant which depends upon both representation and temperature. The values of renormaliz

Donghi Lee

Let u be a cyclic word in a free group F_n of finite rank n that has the minimum length over all cyclic words in its automorphic orbit, and let N(u) be the cardinality of the set {v: |v|=|u| and v= ϕ(u) for some ϕ\in \text {Aut}F_n}. In this paper, we prove that N(u) is bounded by a polynomial function with respect to |u| under the hypothesis that if two let

M. S. Shahriar, Y. Tan, M. Jheeta, J. Morzinksi

We demonstrate an atomic interferometer in which the atom passes through a single-zone optical beam, consisting of a pair of bichromatic counter-propagating fields. During the passage, the atomic wave packets in two distinct internal states trace out split trajectories, guided by the optical beams, with the amplitude and spread of each wave-packet varying co

Thomas B. Bahder, William M. Golding

We present an algorithm for synchronizing two clocks based on second-order quantum interference between entangled photons generated by parametric down-conversion. The procedure is distinct from the standard Einstein two-way clock synchronization method in that photon correlations are used to define simultaneous events in the frame of reference of a Hong-Ou-M

F. Sciarrino, C. Sias, M. Ricci, F. De Martini

We present a computational circuit which realizes contextually the Tele-UNOT gate and the universal optimal quantum cloning machine (UOQCM). We report the experimental realization of the probabilistic UOQCM with polarization encoded qubits. This is achieved by combining on a symmetric beam-splitter the input qubit with an ancilla in a fully mixed state.

Vasily E. Tarasov

A generalization of canonical quantization which maps a dynamical operator to a dynamical superoperator is suggested. Weyl quantization of dynamical operator, which cannot be represented as Poisson bracket with some function, is considered. The usual Weyl quantization of observables is a specific case of suggested quantization. This approach allows to define

Matthew J. Donald

For many years, Henry Stapp and I have been working separately and independently on mind-centered interpretations of quantum theory. In this review, I discuss his work and contrast it with my own. There is much that we agree on, both in the broad problems we have addressed and in some of the specific details of our analyses of neural physics, but ultimately

Mitsuru Hamada

Two observations are given on the fidelity of schemes for quantum information processing. In the first one, we show that the fidelity of a symplectic (stabilizer) code, if properly defined, exactly equals the `probability&#39; of the correctable errors for general quantum channels. The second observation states that for any coding rate below the quantum capa

T. S. Mahesh, Neeraj Sinha, Arindam Ghosh, Ranabir Das

The enormous theoretical potential of Quantum Information Processing (QIP) is driving the pursuit for its practical realization by various physical techniques. Currently Nuclear Magnetic Resonance (NMR) has been the forerunner by demonstrating a majority of quantum algorithms. In NMR, spin systems consisting of coupled nuclear spins are utilized as qubits. I

Kasper Astrup Eriksen

How DNA repair enzymes find the relatively rare sites of damage is not known in great detail. Recent experiments and molecular data suggest that the individual repair enzymes do not work independently of each other, but rather interact with each other through currents exchanged along DNA. A damaged site in DNA hinders this exchange and this makes it possible

Suckjoon Jun, John Herrick, Aaron Bensimon, John Bechhoefer

In Xenopus early embryos, replication origins neither require specific DNA sequences nor is there an efficient S/M checkpoint, even though the whole genome (3 billion bases) is completely duplicated within 10-20 minutes. This leads to the&#34;random-completion problem&#34; of DNA replication in embryos, where one needs to find a mechanism that ensures comple

Alexander V. Bulgakov, Igor Ozerov, Wladimir Marine

Positively charged zinc oxide clusters ZnnOm (up to n = 16, m <= n) of various stoichiometry were synthesized in the gas phase by excimer ArF laser ablation of a ZnO target and investigated using time-of-flight mass spectrometry. Depending on ablation conditions, either metal rich or stoichiometric clusters dominate in the mass spectrum. When the irradiated

G. Puentes, A. Aiello, J. P. Woerdman

We present a numerical investigation of the ray dynamics in a paraxial optical cavity when a ray splitting mechanism is present. The cavity is a conventional two-mirror stable resonator and the ray splitting is achieved by inserting an optical beam splitter perpendicular to the cavity axis. We show that depending on the position of the beam splitter the opti

V. G. Gurzadyan

This illustrated article represents a popular account of the study of the Babylonian astronomical records of Enuma Anu Enlil tablet series i.e. of the Venus Tablet of Ammisaduqa and of two lunar eclipses linked with the IIIrd dynasty of Ur, having resulted in the proposal of Ultra-Low chronology of the Near East in II millennium B.C. The emerged Ultra-Low ch

Matthias F. M. Lutz

In this talk we review the consequences of the chiral SU(3) symmetry for strangeness propagation in nuclear matter. Objects of crucial importance are the meson-baryon scattering amplitudes obtained within the chiral coupled-channel effective field theory. Results for antikaon and hyperon-resonance spectral functions in cold nuclear matter are presented and d

S. Goriely, M. Samyn, M. Bender, J. M. Pearson

We have constructed four new complete mass tables, referred to as HFB-4 to HFB-7, each one including all the 9200 nuclei lying between the two drip lines over the range of Z and N>8 and Z<120. HFB-4 and HFB-5 have the isoscalar effective mass M*_s$ constrained to the value 0.92 M, with the former having a density-independent pairing, and the latter a density

Matthias F. M. Lutz

In this talk we review the important role played by chiral SU(3) symmetry in hadron physics. Exciting new results on the formation of baryon resonances as implied by chiral coupled-channel dynamics are presented and discussed. The results are the consequence of progress made in formulating a consistent effective field theory for the meson-baryon scattering p

D. E. Lanskoy, Y. Yamamoto

Properties of hypernuclei $_{ΛΛ}^5$H and $_{ΛΛ}^5$He are studied in a two-channel approach with explicit treatment of coupling of channels ^3\text{Z}+Λ+Λand α+Ξ. Diagonal ΛΛand coupling ΛΛ-ΞN interactions are derived within G-matrix procedure from Nijmegen meson-exchange models. Bond energy ΔB_{ΛΛ} in $_{ΛΛ}^5$He exceeds significantly that in $_{ΛΛ}^5$H due

E. S. Fraga, Y. Hatta, R. D. Pisarski, J. Schaffner-Bielich

We discuss recent results for the equation of state for cold and dense strongly interacting matter. We consider the extreme cases of very high densities, where weak-coupling approaches may in principle give reasonable results, and very low densities, where we use the framework of heavy-baryon chiral perturbation theory. We also speculate on the nature of the

J. Černý, Z. Doležal, M. P. Ivanov, E. S. Kuzmin

The study of the neutron response and n-gamma discrimination for small (18x26x8) mm3 liquid scintillator BC501A (Bicron) detector was carried out by digital charge comparison method. Three ranges of neutron energies were used: uniform distribution from 0.95 MeV to 1.23 MeV, continuous spectra of AmBe source and monoenergetic 16.2 MeV neutrons. The obtained r

R. Chechik, A. Breskin, G. P. Guedes, D. Moermann

We present results from our recent investigations on detectors comprising cascaded gas electron multipliers (GEM) and cascaded GEMs with micro-hole and strip (MHSP) electrodes. We discuss the factors governing the operation of these fast radiation imaging detectors, that have single-charge sensitivity. The issue of ion-backflow and ion-induced secondary effe

Arturo C. Marti, C. Masoller

We study the synchronization of a coupled map lattice consisting of a one-dimensional chain of logistic maps. We consider global coupling with a time-delay that takes into account the finite velocity of propagation of interactions. We recently showed that clustering occurs for weak coupling, while for strong coupling the array synchronizes into a global stat

S. Yu. Sakovich

The new generalized Harry Dym equation, recently introduced by Z. Popowicz in Phys. Lett. A 317, 260--264 (2003), is transformed into the Hirota--Satsuma system of coupled KdV equations.