July 2005 arXiv papers — page 5

A. A. Mikhailov, N. N. Efremov

Arrival directions of cosmic rays with the energy E>4.10^19 eV are analyzed on the basis of the Yakutsk and AGASA extensive air shower arrays. It is supposed that the clusters can be formed as a result of fragmentation of superheavy nuclei. The consequences of this supposition compare with experimental data. Part of clusters with E>2.10^19 eV correlate with

A. A. Mikhailov, N. N. Efremov, N. S. Gerasimova, I. T. Makarov

It is proposed a new approach for estimating the composition of cosmic rays. It is found that the zenith angle distributions and muon components of EAS for energies E>10^19 eV and E>4.10^19 eV differ from each other. It is shown that the cosmic rays above E>4.10^19 eV is heavier than the cosmic rays at energy E~ 10^19 eV. According to our estimation the SUGA

A. A. Mikhailov, N. N. Efremov, E. S. Nikiforova

Extensive air showers of cosmic rays with energies above 5.10**18 eV registered by the Yakutsk array have been analyzed. The existence of showers without muon component is found. Among them we found 5 clusters and these clusters correlate with nearest pulsars. It is found that there exist 4 classes of showers. Showers with high content of muons are mainly ob

Gert Huetsi

We calculate the redshift-space power spectrum of the Sloan Digital Sky Survey (SDSS) Luminous Red Galaxy (LRG) sample, finding evidence for a full series of acoustic features down to the scales of ~0.25 h Mpc^{-1}. This corresponds up to the 9. peak in the CMB angular power spectrum. The acoustic scale derived, (107.8 +- 4.3) h^{-1}Mpc (k < 0.2 h Mpc^{-1}),

J. L. Donley, G. H. Rieke, J. R. Rigby, P. G. Perez-Gonzalez

We define a sample of 27 radio-excess AGN in the Chandra Deep Field North by selecting galaxies that do not obey the radio/infrared correlation for radio-quiet AGN and star-forming galaxies. Approximately 60% of these radio-excess AGN are X-ray undetected in the 2 Ms Chandra catalog, even at exposures of > 1 Ms; 25% lack even 2-sigma X-ray detections. The ab

J. Meaburn, J. A. Lopez, W. Steffen, M. F. Graham

Spatially resolved profiles of the Halpha and [NII] lines have been obtained at unprecendented signal--to--noise ratios over the outflowing lobes of the high--excitation, poly--polar planetary nebula NGC~6302. A deep image in the light of [NII]6584 A was also obtained of the extremities of the prominent north--western lobe. The Manchester Echelle spectromete

T. M. Heckman, A. Ptak, A. Hornschemeier, G. Kauffmann

In this paper we assess the relationship of the population of Active Galactic Nuclei (AGN) selected by hard X-rays to the traditional population of AGN with strong optical emission lines. First, we study the emission-line properties of a new hard X-ray selected sample of 47 local AGN (classified optically as both Type 1 and Type 2 AGN). We find that the hard

Haojing Yan, Mark Dickinson, Daniel Stern, Peter R. M. Eisenhardt

We use data from the first epoch of observations with the IRAC/Spitzer for the GOODS to detect and study a collection of LBGs at z ~ 6 to 5 in the HUDF, six of which have spectroscopic confirmation. At these redshifts, IRAC samples rest-frame optical light in the range 0.5 to 0.8 um, where the effects of dust extinction are smaller and the sensitivity to lig

P. Mohr

The cross section of the 16O(a,g)20Ne capture reaction is analyzed at low energies where the direct capture mechanism is dominant. For temperatures below T9 = 0.2 the resulting astrophysical reaction rate is about a factor of two higher than in a recent compilation whereas the energy dependence of the astrophysical S-factor and the branching ratios to the 20

Heidi Jo Newberg, Brian Yanny

We present minimum chi-squared fits of power law and Hernquist density profiles to F-turnoff stars in eight 2.5 deg wide stripes of SDSS data: five in the North Galactic Cap and three in the South Galactic cap. Portions of the stellar Galactic halo that are known to contain large streams of tidal debris or other lumpy structure, or that may include significa

Beverly J. Smith, C. Struck, P. N. Appleton, V. Charmandaris

We present Spitzer infrared imaging of the peculiar galaxy pair Arp 107, and compare with an optical H-alpha map and a numerical model of the interaction. The [3.6 micron] - [4.5 micron] colors of clumps in the galaxy do not vary around the ring-like primary spiral arm and are consistent with those of stars, thus these bands are dominated by starlight. In co

A. Iovino, H. J. McCracken, B. Garilli, S. Foucaud

In this paper we present a new deep, wide-field near-infrared imaging survey. Our J- and K-band observations in four separate fields complement optical BVRI, ultraviolet and spectroscopic observations undertaken as part of the VIMOS-VLT deep survey (VVDS). In total, our survey spans ~400arcmis^2. Our catalogues are reliable in all fields to at least Kvega~20

A. P. Lobanov

Radio spectroscopy offers a number of tools for studying a large variety of astrophysical phenomena, ranging from stars and their environment to interstellar and intergalactic medium, active galactic nuclei (AGN) and distant quasars. Main targets of extragalactic radio spectroscopy are atomic and molecular material in galaxies, HII regions, and maser emissio

A. Riciputi, B. Lanzoni, S. Bonoli, L. Ciotti

The contribution of ordered rotation to the observed tilt and thickness of the Fundamental Plane of elliptical galaxies is studied by means of oblate, two-integrals cuspy galaxy models with adjustable flattening, variable amount of ordered rotational support, and possible presence of a dark matter halo and of a central super-massive black hole. We find that,

s Eye Collaboration

We report the results of a search for point-like deviations from isotropy in the arrival directions of ultra-high energy cosmic rays in the northern hemisphere. In the monocular data set collected by the High-Resolution Fly&#39;s Eye, consisting of 1,525 events with energy exceeding 10^18.5 eV, we find no evidence for point-like excesses. We place 90% c.l. u

D. R. Williams, T. Toeroek, P. Demoulin, L. van Driel-Gesztelyi

We present rapid-cadence Transition Region And Coronal Explorer (TRACE) observations which show evidence of a filament eruption from active region NOAA 10696, accompanied by an X2.5 flare, on 2004 November 10. The eruptive filament, which manifests as a fast coronal mass ejection some minutes later, rises as a kinking structure with an apparently exponential

A. Malizia, L. Bassani, J. B. Stephen, A. Bazzano

We report on INTEGRAL observations of AX J1838.0-0655, one of the unidentified objects listed in the first IBIS/ISGRI survey catalogue and located in the Scutum arm region. This object, detected in the 20-300 keV band at a confidence level of 15.3 sigma (9 x 10^-11 erg cm-2 s-1) is the likely counterpart of the still unidentified TeV source HESS J1837-069. I

Glennys R. Farrar, Andreas A. Berlind, David W. Hogg

We investigate the origin of a nearly pointlike cluster of 5 ultrahigh energy cosmic rays at RA ~169.2deg and dec ~56.8deg, using Sloan Digital Sky Survey and other data. No particular source candidates are found near the estimated source direction, but the direction is exceptional in having a likely merging pair of galaxy clusters at 140/h Mpc, with an unus

Guenter Sigl, Eric Armengaud

It has recently been suggested that ultra-high energy cosmic rays could have an extragalactic origin down to the &#34;second knee&#34; at ~4x10^{17}eV. In this case the &#34;ankle&#34; or &#34;dip&#34; at ~5x10^{18}eV would be due to pair production of extragalactic protons on the cosmic microwave background which requires an injection spectrum of about E^{-

B. Cameron Reed

The Sun&#39;s vertical displacement from the galactic plane is determined model-independently from 3457 spectroscopic-parallax distance estimates for 2397 OB stars within 1200 pc of the Sun. The result, 19.5 +/- 2.2 pc, agrees well with other recent determinations. The distribution of stellar z-values with galactic longitude shows a slight sinusoidal depende

Jan M. Swart

This paper studies contact processes on general countable groups. It is shown that any such contact process has a well-defined exponential growth rate, and this quantity is used to study the process. In particular, it is proved that on any nonamenable group, the critical contact process dies out.

G. Abal, R. Siri, A. Romanelli, R. Donangelo

The conditional shift in the evolution operator of a quantum walk generates entanglement between the coin and position degrees of freedom. This entanglement can be quantified by the von Neumann entropy of the reduced density operator (entropy of entanglement). In the long time limit, it converges to a well defined value which depends on the initial state. Ex

Steven R. Furlanetto, Marc Kamionkowski

We study analytically the possibility that mergers of haloes are more highly clustered than the general population of haloes of comparable masses. We begin by investigating predictions for merger bias within the extended Press-Schechter formalism and discuss the limitations and ambiguities of this approach. We then postulate that mergers occur whenever two o

Alison L. Coil, Brian F. Gerke, Jeffrey A. Newman, Chung-Pei Ma

We study the clustering properties of groups and of galaxies in groups in the DEEP2 Galaxy Redshift Survey dataset at z~1. Four clustering measures are presented: 1) the group correlation function for 460 groups with estimated velocity dispersions of sigma>200 km/s, 2) the galaxy correlation for the full galaxy sample, using a flux-limited sample of 9800 obj

L. Grandchamp, S. Lumpkins, D. Sun, H. van Hees

Properties of bottomonia (Upsilon, chi_b and Upsilon&#39;) in the Quark-Gluon Plasma (QGP) are investigated by assessing inelastic reaction rates and their interplay with open-bottom states (b-quarks or B-mesons) and color-screening. The latter leads to vanishing quarkonium binding energies at sufficiently high temperatures (close to the dissolution point),

Peter G. Shepard

We study the microstates of the ``small&#39;&#39; black hole in the $\half$-BPS sector of AdS$_5\times S^5$, the superstar of Myers and Tafjord, using the powerful holographic description provided by LLM. The system demonstrates the inherently statistical nature of black holes, with the geometry of Myer and Tafjord emerging only after averaging over an ensem

Zinovy Reichstein, Nikolaus Vonessen

We show that the fixed elements for the natural GL_m-action on the universal division algebra UD(m,n) of m generic n x n matrices form a division subalgebra of degree n, assuming n >= 3 and 2 <= m <= n^2 - 2. This allows us to describe the asymptotic behavior of the dimension of the space of SL_m-invariant homogeneous central polynomials p(X_1,...,X_m) for n

P. M. Stevenson

Predictions for (phi^4)_4 theory from renormalization-group-improved perturbation theory, as formulated by Luescher and Weisz, are compared to published (and some unpublished) data from lattice Monte-Carlo simulations of the 4-dimensional Ising model. Good agreement is found in all but one respect:-- the change in the wavefunction-renormalization constant Z_

Alex V. Kontorovich

Selberg identified the &#34;parity&#34; barrior, that sieves alone cannot distinguish between integers having an even or odd number of factors. We give here a short and self-contained demonstration of parity breaking using bilinear forms, modeled on the Twin Primes Conjecture.

Adan Cabello

We introduce an all-versus-nothing proof of impossibility of Einstein-Podolsky-Rosen&#39;s local elements of reality for two photons entangled both in polarization and path degrees of freedom, which leads to a Bell&#39;s inequality where the classical bound is 8 and the quantum prediction is 16. A simple estimation of the detection efficiency required to clo

D. A. Dale, G. J. Bendo, C. W. Engelbracht, K. D. Gordon

The Spitzer Infrared Nearby Galaxies Survey (SINGS) is carrying out a comprehensive multi-wavelength survey on a sample of 75 nearby galaxies. The 1-850um spectral energy distributions are presented using broadband imaging data from Spitzer, 2MASS, ISO, IRAS, and SCUBA. The infrared colors derived from the globally-integrated Spitzer data are generally consi

Adan Cabello

We introduce a two-observer all-versus-nothing proof of Bell&#39;s theorem which reduces the number of required quantum predictions from 9 [A. Cabello, Phys. Rev. Lett. 87, 010403 (2001); Z.-B. Chen et al., Phys. Rev. Lett. 90, 160408 (2003)] to 4, provides a greater amount of evidence against local realism, reduces the detection efficiency requirements for

Shahn Majid

We illustrate the thesis that if time did not exist, we would have to create it if space is noncommutative, and extend functions by something like Schroedinger&#39;s equation. We propose that the phenomenon is a somewhat general mechanism within noncommutative geometry for `spontaneous time generation&#39;. We show in detail how this works for the $su_2$ alg

T. Foglizzo, L. Scheck, H. -Th. Janka

A toy model is analyzed in order to evaluate the linear stability of the gain region immediately behind a stalled accretion shock, after core bounce. This model demonstrates that a negative entropy gradient is not sufficient to warrant linear instability. The stability criterion is governed by the ratio χof the advection time through the gain region divided

Anindya Biswas, Sudipta Mukherji

We consider a dynamical two-brane in a four dimensional black hole background with scalar hair. At high temperature this black hole goes through a phase transition by radiating away the scalar. The end phase is a topological adS-Schwarzschild black hole. We argue here that for a sufficiently low temperature, the brane motion in this geometry is non-singular.

Martin S. Sloth

We consider the possibility of suppressing superhorizon curvature perturbations after the end of the ordinary slow-roll inflationary stage. This is the opposite of the curvaton limit. We assume that large curvature perturbations are created by the inflaton and investigate if they can be diluted or suppressed by a second very homogeneous field which starts to

P. W. Anderson, W. F. Brinkman, David A. Huse

We present a simple theory of the thermodynamics of an incommensurate quantum solid. The ground state of the solid is assumed to be an incommensurate crystal, with quantum zero-point vacancies and interstitials and thus a non-integer number of atoms per unit cell. We show that the low temperature variation of the net vacancy concentration should be as $T^4$,

L. J. Mason

Twistor space constructions and actions are given for full Yang-Mills and conformal gravity using almost complex structures that are not, in general, integrable. These are used as the basis of a derivation of the twistor-string generating functionals for tree level perturbative scattering amplitudes of Yang-Mills and conformal gravity. The derivation follows

M. Roncarelli, L. Moscardini, P. Tozzi, S. Borgani

We study the properties of the diffuse X-ray background by using the results of a cosmological hydrodynamical simulation of the concordance LambdaCDM model. The simulation follows gravitational and gas dynamics and includes a treatment of physical processes like radiative cooling, star formation and supernova feedback. From the simulation outputs, we produce

Viviana Acquaviva, Carlo Baccigalupi

We consider the weak lensing effect induced by linear cosmological perturbations on the cosmic microwave background (CMB) polarization anisotropies. We find that the amplitude of the lensing peak in the BB mode power spectrum is a faithful tracer of the dark energy dynamics at the onset of cosmic acceleration. This is due to two reasons. First, the lensing p

A. N. Gorban

After Boltzmann and Gibbs, the notion of disorder in statistical physics relates to ensembles, not to individual states. This disorder is measured by the logarithm of ensemble volume, the entropy. But recent results about measure concentration effects in analysis and geometry allow us to return from the ensemble--based point of view to a state--based one, at

P. I. Hurtado, S. Redner

We study the dynamics of three particles in a finite interval, in which two light particles are separated by a heavy ``piston&#39;&#39;, with elastic collisions between particles but inelastic collisions between the light particles and the interval ends. A symmetry breaking occurs in which the piston migrates near one end of the interval and performs small-a

Theodora Ioannidou, Burkhard Kleihaus

We construct non-BPS regular and black hole solutions of N=4 SU(N) supersymmetric Yang-Mills theory coupled to Einstein gravity. Our numerical studies reveal a number of interesting phenomena when the gravitational constant $\alpha=M_{YM}/gM_{Planck}$ (where $M_{Planck}$ is the Planck mass and $M_{YM}$ is the monopole mass) is either weak (flat limit) or com

S. Satyapal, R. P. Dudik, B. O&#39;Halloran, M. Gliozzi

We present archival high resolution X-ray imaging observations of 25 nearby LINERs observed by ACIS on board Chandra. This sample builds on our previously published proprietary and archival X-ray observations, and includes the complete set of LINERs with published black hole masses and FIR luminosities that have been observed by Chandra. Of the 82 LINERs obs

J. L. F. Barbón, C. Hoyos

We consider the small-volume dynamics of nonsupersymmetric orbifold and orientifold field theories defined on a three-torus, in a test of the claimed planar equivalence between these models and appropriate supersymmetric ``parent models&#34;. We study one-loop effective potentials over the moduli space of flat connections and find that planar equivalence is

Erin De Pree, Marc Sher

In models with universal extra dimensions, the isosinglet Kaluza-Klein (KK) quarks, q^1, have very narrow widths, of O(5-10) MeV, and will thus hadronize. Studies of KK-quarkonia, \bar{q}^1 q^1, show very sharp resonances and dramatic signatures at the Linear Collider. In this Brief Report, we consider the possibility of detecting KK-mesons, \bar{q}^1 q, and

Li-Jie Zhang, Yu-Xiao Liu, Ji-Rong Ren

We investigate the new spinor field realizations of the $W_{3}$ algebra, making use of the fact that the $W_{3}$ algebra can be linearized by the addition of a spin-1 current. We then use these new realizations to build the nilpotent Becchi-Rouet-Stora--Tyutin (BRST) charges of the spinor non-critical $W_{3}$ string.

R. N. Mohapatra, W. Rodejohann

We propose that leptonic CP violation arises from a breaking of the mu-tau exchange symmetry in the neutrino mass matrix which in turn is indicated by the near maximal atmospheric neutrino mixing and the near zero θ_{13}. We find that for the case of a normal hierarchy, present data already restricts the way CP violation may appear in the neutrino mass matri

J. Farihi, B. Zuckerman, E. E. Becklin

Fluxes are measured for the DA white dwarf plus brown dwarf pair GD 1400 with the Infrared Array Camera on the {\em Spitzer Space Telescope}. GD 1400 displays an infrared excess over the entire $3-8μ$m region consistent with the presence of a mid- to late-type L dwarf companion. A discussion is given regarding current knowledge of this unique system.

Sudipta Das, Narayan Banerjee

In this paper it is shown that the Brans - Dicke scalar field itself can serve the purpose of providing an early deceleration and a late time acceleration of the universe without any need of quintessence field if one considers an interaction, i.e, transfer of energy between the dark matter and the Brans - Dicke scalar field.

J. Gracia, N. Vlahakis, K. Tsinganos

We perform a numerical simulation of magnetohydrodynamic radially self-similar jets, whose prototype is the Blandford & Payne analytical example. The reached final steady state is valid close to the rotation axis and also at large distances above the disk where the classical analytical model fails to provide physically acceptable solutions. The outflow start

Markus Schmidmeier

Fix a poset $P$ and a natural number $n$. For various commutative local rings $Λ$, each of Loewy length $n$, consider the category $\textrm{sub}_ΛP$ of $Λ$-linear submodule representations of $P$. We give a criterion for when the underlying translation quiver of a connected component of the Auslander-Reiten quiver of $\textrm{sub}_ΛP$ is independent of the c

Giampiero Esposito, Guglielmo Fucci, Alexander Yu. Kamenshchik, Klaus Kirsten

Recent work on Euclidean quantum gravity on the four-ball has proved regularity at the origin of the generalized zeta-function built from eigenvalues for metric and ghost modes, when diffeomorphism-invariant boundary conditions are imposed in the de Donder gauge. The hardest part of the analysis involves one of the four sectors for scalar-type perturbations,

P. Chomaz, F. Gulminelli, C. Ducoin, P. Napolitani

In this letter we show that the presence of the long-range Coulomb force in dense stellar matter implies that the total charge cannot be associated with a chemical potential, even if it is a conserved quantity. As a further consequence, the analytical properties of the partition sum are modified, changing the order of the phase transitions and affecting the

Bruce A. Bassett, Shinji Tsujikawa, David Wands

We review the theory of inflation with single and multiple fields paying particular attention to the dynamics of adiabatic and entropy/isocurvature perturbations which provide the primary means of testing inflationary models. We review the theory and phenomenology of reheating and preheating after inflation providing a unified discussion of both the gravitat

S. Davatolhagh

There are two independent critical exponents that describe the behavior of systems near their critical point. However, at the critical point only the exponent $η$, which describes the decay of the correlation function, is usually discussed. We emphasize that there is a second independent exponent $η&#39;$ that describes the decay of the fourth-order correlat

Joydev Lahiri, Gautam Bhattacharya

We develop a general formalism for analyzing linear perturbations in multiple-field cosmological inflation based on the gauge-ready approach. Our inflationary model consists of an arbitrary number of scalar fields with non-minimal kinetic terms. We solve the equations for scalar- and tensor-type perturbations during inflation to the first order in slow-roll,

Bernard Julia, Jerome Levie, Sebastien Ray

Gravitational instantons &#39;&#39;Lambda-instantons&#39;&#39; are defined here for any given value Lambda of the cosmological constant. A multiple of the Euler characteristic appears as an upper bound for the de Sitter action and as a lower bound for a family of quadratic actions. The de Sitter action itself is found to be equivalent to a simple and natural

V. Guzey, M. Strikman

We use the Glauber-Gribov multiple scattering formalism and the theory of leading twist nuclear shadowing to develop a method for the calculation of leading twist hard coherent diffraction in hadron-nucleus processes. We demonstrate that soft multiple rescatterings lead to the factorization breaking of hard diffraction in proton-nucleus scattering, which is

Kenneth Günter, Thilo Stöferle, Henning Moritz, Michael Köhl

We study a spin-polarized degenerate Fermi gas interacting via a p-wave Feshbach resonance in an optical lattice. The strong confinement available in this system allows us to realize one- and two-dimensional gases and therefore to restrict the asymptotic scattering states of atomic collisions. When aligning the atomic spins along (or perpendicular to) the ax

Atsushi Taruya, Hideaki Kudoh

We present a perturbative reconstruction method to make a skymap of gravitational-wave backgrounds (GWBs) observed via space-based interferometer. In the presence of anisotropies in GWBs, the cross-correlated signals of observed GWBs are inherently time-dependent due to the non-stationarity of the gravitational-wave detector. Since the cross-correlated signa

R. A. Pinto, S. Flach

We study the time evolution of localized (local bond) excitations in a symmetric quantum trimer molecule. We relate the dynamical properties of localized excitations such as their spectral intensity and their temporal evolution (survival probability and tunneling of bosons) to their degree of overlap with quantum tunneling pair states. We report on the exist

Holger Mueller, Sheng-wey Chiow, Quan Long, Steven Chu

We demonstrate phase lock of two >1.6W Titanium:sapphire lasers with a phase noise of -138dBc/Hz at 1MHz from the carrier, using an intra-cavity electro-optic phase modulator. The residual phase variance is 2.5 10^(-8)rad^2 integrated from 1Hz to 10kHz. Instantaneous offset frequency steps of up to 4MHz are achieved within 200ns. Simultaneous atom interferom

Peter Cahill, Kevin Cahill

It is hard to understand spin-one-half fields without reading Weinberg. This paper is a pedagogical footnote to his formalism with an emphasis on the boost matrix, spinors, and Majorana fields.

Lev Kofman, Piljin Yi

In String theory realizations of inflation, the end point of inflation is often brane-anti brane annihilation. We consider the processes of reheating of the Standard Model universe after brane inflation. We identify the channels of inflaton energy decay, cascading from tachyon annihilation through massive closed string loops, KK modes, and brane displacement

F. M. Izrailev, A. Castaneda-Mendoza

We analyze, both analytically and numerically, the time-dependence of the return probability in closed systems of interacting particles. Main attention is paid to the interplay between two regimes, one of which is characterized by the Gaussian decay of the return probability, and another one is the well known regime of the exponential decay. Our analytical e

E791 Collaboration, E. Aitala

A model-independent partial-wave analysis of the \swave component of the $Kπ$ system from decays of $D^{+}$ mesons to the three-body $\Km\pip\pip$ final state is described. Data come from the Fermilab E791 experiment. Amplitude measurements are made independently for ranges of $\Km\pip$ invariant mass, and results are obtained below 825 \MeVcc, where previou

Suranjana Rai, Jagdish R. Luthra

Two measures of entanglement, negativity and concurrence are studied for two qutrits. An operator origin of negativity is presented and an analytic formula connecting the two measures is derived.

Rodolfo Gambini, Rafael A. Porto, Jorge Pullin

Lloyd has considered the ultimate limitations physics places on quantum computers. He concludes in particular that for an ``ultimate laptop&#39;&#39; (a computer of one liter of volume and one kilogram of mass) the maximum number of operations per second is bounded by $10^{51}$. The limit is derived considering ordinary quantum mechanics. Here we consider ad

M. I. Dykman

We show that nonlinear response of a quantum oscillator displays antiresonant dips and resonant peaks with varying frequency of the driving field. The effect is a consequence of special symmetry and is related to resonant multiphoton mixing of several pairs of oscillator states at a time. We also discuss escape from a metastable state of forced vibrations. T

Matthias Homeister, Stephan Waack

Quantum branching programs (quantum binary decision diagrams, respectively) are a convenient tool for examining quantum computations using only a logarithmic amount of space. Recently several types of restricted quantum branching programs have been considered, e. g. read--once quantum branching programs. This paper considers quantum ordered binary decision d

T. M. Stace, H. M. Wiseman

Coupling the output of a source quantum system into a target quantum system is easily treated by cascaded systems theory if the intervening quantum channel is dispersionless. However, dispersion may be important in some transfer protocols, especially in solid-state systems. In this paper we show how to generalize cascaded systems theory to treat such dispers

Mark Sadgrove, Sandro Wimberger, Scott Parkins, Rainer Leonhardt

We present mean energy measurements for the atom optics kicked rotor as the kicking period tends to zero. A narrow resonance is observed marked by quadratic energy growth, in parallel with a complete freezing of the energy absorption away from the resonance peak. Both phenomena are explained by classical means, taking proper account of the atoms&#39; initial

V. Ya. Demikhovskii, F. M. Izrailev, A. I. Malyshev

We study the quantum Arnol&#39;d diffusion for a particle moving in a quasi-1D waveguide bounded by a periodically rippled surface, in the presence of the time-periodic electric field. It was found that in a deep semiclassical region the diffusion-like motion occurs for a particle in the region corresponding to a stochastic layer surrounding the coupling res

Volkan Sevim, Per Arne Rikvold

Models of coevolution have recently been studied, in which a species is defined by a genome in the form of a bitstring, and the interactions between species i and j are given by a fixed matrix with independent, randomly distributed elements M_{ij}. A consequence of the stochastic independence is that species whose genotypes differ even by a single bit may ha

Eugenio Lippiello, Cataldo Godano, Lucilla de Arcangelis

One of the main interests in seismology is the formulation of models able to describe the clustering in time occurrence of earthquakes. Analysis of the Southern California Catalog shows magnitude clustering in correspondence to temporal clustering. Here we propose a dynamical scaling hypothesis in which time is rescaled in terms of magnitude. This hypothesis

Alessandro Scirè, Idán Tuval, Víctor M. Eguíluz

We introduce a model for the dynamic self-organization of the electric grid. The model is characterized by a conserved magnitude, energy, that can travel following the links of the network to satisfy nodes&#39; load. The load fluctuates in time causing local overloads that drive the dynamic evolution of the network topology. Our model displays a transition f

Jeremy Butterfield

This paper expounds the modern theory of symplectic reduction in finite-dimensional Hamiltonian mechanics. This theory generalizes the well-known connection between continuous symmetries and conserved quantities, i.e. Noether&#39;s theorem. It also illustrates one of mechanics&#39; grand themes: exploiting a symmetry so as to reduce the number of variables n

Jeremy Butterfield

This paper expounds the relations between continuous symmetries and conserved quantities, i.e. Noether&#39;s ``first theorem&#39;&#39;, in both the Lagrangian and Hamiltonian frameworks for classical mechanics. This illustrates one of mechanics&#39; grand themes: exploiting a symmetry so as to reduce the number of variables needed to treat a problem. I empha

D0 Collaboration

The D0 experiment enjoyed a very successful data-collection run at the Fermilab Tevatron collider between 1992 and 1996. Since then, the detector has been upgraded to take advantage of improvements to the Tevatron and to enhance its physics capabilities. We describe the new elements of the detector, including the silicon microstrip tracker, central fiber tra

B. Rothenstein, G. J. Spix

Considering a system of non-interacting particles characterized by the number N of its constituents and by its Kelvin temperature T, we reduce the transformation of the Kelvin temperature to the transformation mass

David Amans, Edouard Brainis, Serge Massar

We study the higher order harmonics of scalar modulational instability in the regime where it arises spontaneously through amplification of vacuum fluctuations. We obtain detailed predictions concerning the detunings, intensities, growth rates and spectral widths of the harmonics. These predictions are well verified by experimental results obtained by propag

Peter Rowlands

It is proposed that the Dirac equation, as normally interpreted, incorporates intrinsic redundancies whose removal necessarily leads to an enormous gain in calculating power and physical interpretation. Streamlined versions of the Dirac equation can be developed which remove the redundancies and singularities from many areas of quantum physics while giving q

Gordon Chalmers

The derivative expnsion in the context of IIB string scattering compactified on non-trivial K3 and other Calabi-Yau manifolds is formulated. The scattering data in terms of automorphic functions can be inverted to find the these metrics. The solutions are parameterized by the moduli information, and the metrics may be found to any desired accuracy in derivat

A. Femius Koenderink, Ad Lagendijk, Willem L. Vos

Unavoidable variations in size and position of the building blocks of photonic crystals cause light scattering and extinction of coherent beams. We present a new model for both 2 and 3-dimensional photonic crystals that relates the extinction length to the magnitude of the variations. The predicted lengths agree well with our new experiments on high-quality

Rodolfo A. Diaz, William J. Herrera, R. Martinez

This paper presents some formulae to calculate moments of inertia for solids of revolution and for solids generated by contour plots. For this, the symmetry properties and the generating functions of the figures are utilized. The combined use of generating functions and symmetry properties greatly simplifies many practical calculations. In addition, the expl

L. G. Cao, U. Lombardo, C. W. Shen, Nguyen Van Giai

A Skyrme-like effective interaction is built up from the equation of state of nuclear matter. The latter is calculated in the framework of the Brueckner-Hartree-Fock approximation with two and three body forces. A complete Skyrme parametrization requires a fit of the neutron and proton effective masses and also the Landau parameters. The new parametrization

T. S. Biro

Quark matter is being expected to be found in heavy ion collisions on the basis of calculations in the framework of traditional, extensive thermodynamics. Recently a non-extensive generalization of the thermodynamics is emerging in the theoretical research. We review here some basic concepts in statistics, kinetic theory and thermodynamics, in particular tho

F. D. Aaron, A. A. Raduta

A sixth order quadrupole boson Hamiltonian is treated through a time dependent variational principle approach choosing as trial function a coherent state with respect to zeroth $b^{\dagger}_0$ and second $b^{\dagger}_2+b^{\dagger}_{-2}$ components of the quadrupole bosons. The coefficients involved in the model Hamiltonian are chosen so that the classical ef

Q. Li, Z. X. Li, S. Soff, Raj K. Gupta

Based on the ultrarelativistic quantum molecular dynamics (UrQMD) model, the effects of the density-dependent symmetry potential for baryons and of the Coulomb potential for produced mesons are investigated for neutron-rich heavy ion collisions at intermediate energies. The calculated results of the $Δ^-/Δ^{++}$ and $π^{-}/π^{+}$ production ratios show a cle

K. Kaneko, M. Hasegawa

We extract pairing gap in $^{184}$W at finite temperature for the first time from the experimental level densities of $^{183}$W, $^{184}$W, and $^{185}$W using &#34;thermal&#34; odd-even mass difference. We found the quenching of pairing gap near the critical temperature $T_c = 0.47$ MeV in the BCS calculations. It is shown that the monopole pairing model wi

NA49 Collaboration

Results are presented from a search for the decays D0 -> Kmin piplus and D0bar -> Kplus pimin in a sample of 3.8x10^6 central Pb-Pb events collected with a beam energy of 158A GeV by NA49 at the CERN SPS. No signal is observed. An upper limit on D0 production is derived and compared to predictions from several models.

H. Aratyn, J. F. Gomes, A. H. Zimerman

A deformation parameter of a bihamiltonian structure of hydrodynamic type is shown to parameterize different extensions of the AKNS hierarchy to include negative flows. This construction establishes a purely algebraic link between, on the one hand, two realizations of the first negative flow of the AKNS model and, on the other, two-component generalizations

Alexey V. Borisov, Ivan S. Mamaev

The Equations of motion of vortex sources (examined earlier by Fridman and Polubarinova) are studied, and the problems of their being Hamiltonian and integrable are discussed. A system of two vortex sources and three sources-sinks was examined. Their behavior was found to be regular. Qualitative analysis of this system was made, and the class of Liouville in

Mihály Weiner

It has been recently noted that the diffeomorphism covariance of a Chiral Conformal QFT in the vacuum sector automatically ensures Möbius covariance in all charged sectors. In this article it is shown that the diffeomorphism covariance and the positivity of the energy in the vacuum sector even ensure the positivity of the energy in the charged sectors. The m

Krzysztof Bogdan, Paweł Sztonyk

We characterize those homogeneous translation invariant symmetric non-local operators with positive maximum principle whose harmonic functions satisfy Harnack&#39;s inequality. We also estimate the corresponding semigroup and the potential kernel.

Enrique Villamor

There have been, over the last 8 years, a number of far reaching extensions of the famous original F. and M. Riesz&#39;s uniqueness theorem that states that if a bounded analytic function in the unit disc of the complex plane $\Bbb C$ has the same radial limit in a set of positive Lebesgue measure on its boundary, then the function has to be constant. First

Enrique Villamor

Let $F\in W_{loc}^{1,n}(Ω;\Bbb R^n)$ be a mapping with non-negative Jacobian $J_F(x)=\text{det} DF(x)\ge 0$ a.e. in a domain $Ω\in \Bbb R^n$. The dilatation of the mapping $F$ is defined, almost everywhere in $Ω$, by the formula $$K(x)={{|DF(x)|^n}\over {J_F(x)}}.$$ If $K(x)$ is bounded a.e., the mapping is said to be quasiregular. Quasiregular mappings are

Hans Engler, Jan Pruess, Glenn F. Webb

A new mathematical model for the dynamics of prion proliferation involving an ordinary differential equation coupled with a partial integro-differential equation is analyzed, continuing earlier work. We show the well-posedness of this problem in a natural phase space, i.e. there is a unique global semiflow in the phase space associated to the problem. A theo

Buma Fridman, Daowei Ma

We study the fixed point sets of holomorphic self-maps of a bounded domain in ${\Bbb C}^n$. Specifically we investigate the least number of fixed points in general position in the domain that forces any automorphism (or endomorphism) to be the identity. We have discovered that in terms of this number one can give the necessary and sufficient condition for th