February 2005 arXiv papers — page 9

M. Pohl, H. Yan, A. Lazarian

We discuss the damping of strong magnetic turbulence downstream of the forward shock of young supernova remnants (SNR). We find that strong magnetic fields, that have been produced by the streaming instability in the upstream region of the shock, or by other kinetic instabilities at the shock, will be efficiently reduced, so the region of enhanced magnetic f

Jean P. Brodie, Jay Strader, Glenda Denicolo, Michael A. Beasley

High signal-to-noise, low-resolution spectra have been obtained for 22 globular clusters (GCs) in NGC 4365. Some of these were selected as probable representatives of an intermediate-age (2-5 Gyr), extremely metal-rich GC subpopulation. The presence of such a subpopulation had been inferred from the unusual optical and near-IR color distributions of GCs in t

Martin Haas Rolf Chini Ulrich Klaas

The collision of gas-rich galaxies is believed to produce strong shocks between their gas clouds which cause the onset of the observed bursts of extended star formation. However, the so far observed shock signatures in colliding galaxies can be explained essentially by winds from already existing massive stars and supernovae and thus do not give any evidence

D. R. Ballantyne, J. E. Everett

Type I X-ray bursts and superbursts on neutron stars release sudden and intense radiation fields into their surroundings. Here, we consider the possible effects of these powerful explosions on the structure of the accretion disk. The goal is to account for the apparent evolution of the innermost regions of the accretion disk around 4U 1820-30 during a superb

A. Sesana, F. Haardt, P. Madau, M. Volonteri

We compute the expected low-frequency gravitational wave signal from coalescing massive black hole (MBH) binaries at the center of galaxies. We follow the merging history of halos and associated holes via cosmological Monte Carlo realizations of the merger hierarchy from early times to the present in a LCDM cosmology. MBHs get incorporated through a series o

D. R. Ballantyne, A. C. Fabian

We present evidence for a broad, ionized Fe K line in the XMM-Newton spectrum of the broad-line radio galaxy (BLRG) 4C+74.26. This is the first indication that the innermost regions of the accretion flow in BLRGs contain thin, radiatively efficient disks. Analysis of the 35 ks XMM-Newton observation finds a broad line with an inner radius close to the innerm

E. Poretti, R. Alonso, P. J. Amado, J. A. Belmonte

The activities related to the preparation of the asteroseismic, photometric space mission COROT are described. Photoelectric observations, wide--field CCD photometry, uvbyB calibrations and further time--series have been obtained at different observatories and telescopes. They have been planned to complete the COROT programme in the direction of the galactic

Donovan L. Domingue, Jack W. Sulentic, Adriana Durbala

Mixed morphology pairs offer a simplification of the interaction equation that involves a gas-rich fast rotator paired with a gas-poor slow rotator. In past low resolution IRAS studies it was assumed that the bulk of the far infrared emission originated in the spiral component. However our ISO studies revealed a surprising number of early-type components wit

Greg L. Bryan, G. Mark Voit

There are (at least) two unsolved problems concerning the current state of the thermal gas in clusters of galaxies. The first is identifying the source of the heating which offsets cooling in the centers of clusters with short cooling times (the ``cooling flow'' problem). The second is understanding the mechanism which boosts the entropy in cluster a

J. I. González Hernández, R. Rebolo, J. Peñarrubia, J. Casares

We present the first determination of the proper motion of the neutron star low mass X-ray binary {Cen X-4} measured from relative astrometry of the secondary star using optical images at different epochs. We determine the Galactic space velocity components of the system and find them to be significantly different from the mean values that characterize the k

Rowin Meijerink, Marco Spaans

We present a far-ultraviolet (PDR) and an X-ray dominated region (XDR) code. We include and discuss thermal and chemical processes that pertain to irradiated gas. An elaborate chemical network is used and a careful treatment of PAHs and H2 formation, destruction and excitation is included. For both codes we calculate four depth-dependent models for different

C. Bonatto, E. Bica, J. F. C. Santos

Luminosity and mass functions in the old open cluster NGC 188 are analysed by means of J and H 2MASS photometry. Within the uncertainties, the observed projected radial density profile of NGC 188 departs from the two-parameter King model in two inner regions, which reflects the non-virialized dynamical state and possibly, some degree of non-sphericity in the

Y. F. Huang

The popular fireball/blastwave model of classical gamma-ray bursts is applied to soft gamma-ray bursts. It is found that X-ray afterglows from strong events may be above their quiescent levels for 40 -- 400 seconds. Optical afterglows may also be detectable. By monitoring the three repeaters, we will have an ideal way to check the fireball/blastwave model.

E. Bica, C. Bonatto

We analyze 9 open clusters with ages in the range 70 Myr to 3.2 Gyr using UCAC2 proper motion data and 2MASS photometry. For each cluster we consider the projected velocity distributions in the core and off-core regions separately. In the projected velocity distribution of all sample clusters we find a well-defined low-velocity peak, as well as an excess in

P. Thebault, J. -C Augereau

We investigate in this paper the effect of gas drag on the dynamics of the dust particles in the edge-on Beta-Pictoris disc in order to derive an upper limit on the mass of gas in this system. Our study is motivated by the large uncertainties on the amount of gas in the Beta-Pictoris disc currently found in the literature. The dust particles are assumed to o

A. L. Roy, W. M. Goss, Niruj R. Mohan, K. R. Anantharamaiah

We have detected the radio recombination lines H91-alpha and H92-alpha with rest frequencies of 8.6 GHz and 8.3 GHz from the starburst nucleus NGC 3256 at an angular resolution of 16.4" x 9.6" using the Australia Telescope Compact Array and at an angular resolution of 12.0" x 2.9" using the VLA. The line was detected at ~ 1 mJy/beam peak with

Genevieve Parmentier, Eva K. Grebel

We investigate what may be the origin of the presently observed spatial distribution of the mass of the Galactic Old Halo globular cluster system. We propose its radial mass density profile to be a relic of the distribution of the cold baryonic material in the protoGalaxy. Assuming that this one arises from the profile of the whole protoGalaxy minus the cont

N. Lodieu, M. J. McCaughrean, D. Barrado y Navascues, J. Bouvier

We present a near-infrared (K'-band) survey of 0.7 square degree area in the Alpha Persei open cluster (age = 90 Myr, distance = 182 pc) carried out with the Omega-Prime camera on the Calar Alto 3.5-m telescope. Combining optical data (Rc and Ic) obtained with the KPNO/MOSA detector and presented in Stauffer et al. (1999) with the K' observations, a

J. Kaluzny, P. Pietrukowicz, I. B. Thompson, W. Krzeminski

We report the detection of a dwarf nova (DN) in the core region of the globular cluster M55. Six outbursts were observed during 8 observing seasons spanning the period 1997-2004. The variable has an X-ray counterpart detected on images taken with the ROSAT telescope. Although we cannot offer proof of cluster membership, one can see that both the position on

S. Recchi, I. J. Danziger

By means of analytical calculations, we explore the self-enrichment scenario for Globular Cluster formation. According to this scenario, an initial burst of star formation occurs inside the core radius of the initial gaseous distribution. The outward-propagating shock wave sweeps up a shell in which gravitational instabilities may arise, leading to the forma

G. Perrin, S. T. Ridgway

In the near infrared where detectors are limited by read-out noise, most interferometers have been operated in wide band in order to benefit from larger photon rates. We analyze in this paper the biases caused by instrumental and turbulent effects to $V^2$ estimators for both narrow and wide band cases. Visibilities are estimated from samples of the interfer

Eric B. Ford, Verene Lystad, Frederic A. Rasio

Doppler spectroscopy has detected 136 planets around nearby stars. A major puzzle is why their orbits are highly eccentric, while all planets in our Solar System are on nearly circular orbits, as expected if they formed by accretion processes in a protostellar disk. Several mechanisms have been proposed to generate large eccentricities after planet formation

P. Lah, L. L. Kiss, T. R. Bedding

We present an analysis of the 3-D structure of the Magellanic Clouds, using period-luminosity (P-L) relations of pulsating red giants in the OGLE-II sample. By interpreting deviations from the mean P-L relations as distance modulus variations, we examine the three-dimensional distributions of the sample. The results for the Large Magellanic Cloud, based sole

J. Besprosvany

The consideration of dark energy's quanta, required also by thermodynamics, introduces its chemical potential into the cosmological equations. Isolating its main contribution, we obtain solutions with dark energy decaying to matter or radiation. When dominant, their energy densities tend asymptotically to a constant ratio, explaining today's dark ene

D. Palle

We study the impact of the cosmological environment on the solar gravitational system by the imbedding formalism of Gautreau. It appears that the cosmic mean-mass density and the cosmological constant give negligibly small contribution to gravity potentials. On the contrary, the cosmic acceleration beyond the Robertson-Walker geometry can considerably influe

Burin Gumjudpai, Tapan Naskar, M. Sami, Shinji Tsujikawa

In dark energy models of scalar-field coupled to a barotropic perfect fluid, the existence of cosmological scaling solutions restricts the Lagrangian of the field $\vp$ to $p=X g(Xe^{λ\vp})$, where $X=-g^{μν} \partial_μ\vp \partial_ν\vp /2$, $λ$ is a constant and $g$ is an arbitrary function. We derive general evolution equations in an autonomous form for th

Marcin M. Jankiewicz, Thomas W. Kephart

We show that there is a set of transformations that relates all of the 24 dimensional even self-dual (Niemeier) lattices, and also leads to non-lattice objects that however cannot be interpreted as a basis for the construction of holomorphic conformal field theory. In the second part of this paper, we extend our observations to higher dimensional conformal f

Kunihito Ioka, Peter Meszaros

We consider the spatial clustering of massive black hole (MBH) mergers, and discuss possible ways to use gravitational wave observations in the LISA and DECIGO/BBO range for obtaining cosmological and cosmogonical information. Constraints on large scale structure (LSS) and merger histories may be possible by detections of an alignment of the GW polarization

Mark Miller

I discuss the accuracy requirements on numerical relativity calculations of inspiraling compact object binaries whose extracted gravitational waveforms are to be used as templates for matched filtering signal extraction and physical parameter estimation in modern interferometric gravitational wave detectors. Using a post-Newtonian point particle model for th

Thomas Lam, Alexander Postnikov, Pavlo Pylyavskyy

We prove Okounkov's conjecture, a conjecture of Fomin-Fulton-Li-Poon, and a special case of Lascoux-Leclerc-Thibon's conjecture on Schur positivity and give several more general statements using a recent result of Rhoades and Skandera. An alternative proof of this result is provided. We also give an intriguing log-concavity property of Schur function

V. Ibarra-Junquera, H. C. Rosu

It is shown that periodic orbits can occur in Cholette's bioreactor model working under the influence of a PI-controller. We find a diffeomorphic coordinate transformation that turns this controlled enzymatic reaction system into a generalized Lienard form. Furthermore, we give sufficient conditions for the existence and uniqueness of limit cycles in the

Shinji Mukohyama

We investigate how the ghost condensate reacts to black holes immersed in it. A ghost condensate defines a hypersurface-orthogonal congruence of timelike curves, each of which has the tangent vector u^μ=-g^{μν}\partial_νϕ. It is argued that the ghost condensate in this picture approximately corresponds to a congruence of geodesics. In other words, the ghost

Charles C. Steidel, Kurt L. Adelberger, Alice E. Shapley, Dawn K. Erb

We have discovered a highly significant over-density of galaxies at z=2.300+/-0.015 in the course of a redshift survey designed to select star-forming galaxies in the redshift range z=2.3+/-0.4 in the field of the bright z=2.72 QSO HS1700+643. The structure has a redshift-space galaxy over-density of delta_g,z ~= 7 and an estimated matter over-density in rea

Rafael Hernandez, Esperanza Lopez, Africa Perianez, German Sierra

N=4 supersymmetric Yang-Mills operators carrying large charges are dual to semiclassical strings in AdS_5xS^5. The spectrum of anomalous dimensions of very large operators has been calculated solving the Bethe ansatz equations in the thermodynamic limit, and matched to energies of string solitons. We have considered finite size corrections to the Bethe equat

Gentaro Watanabe, Hidetaka Sonoda

More than twenty years ago, it was predicted that nuclei can adopt interesting shapes, such as rods or slabs, etc., in the cores of supernovae and the crusts of neutron stars. These non-spherical nuclei are referred to as nuclear "pasta". In recent years, we have been studying the dynamics of the pasta phases using a method called quantum molecular d

Luisa Sabrina Stark, Petra Hafliger, Adrian Biland, Felicitas Pauss

In minimal Supergravity (mSUGRA) models the lightest supersymmetric particle (assumed to be the lightest neutralino) provides an excellent cold dark matter (CDM) candidate. The supersymmetric parameter space is significantly reduced, if the limits on the CDM relic density, obtained from WMAP data, are used. Assuming a vanishing trilinear scalar coupling A0 a

Katherine Freese, James T. Liu, Douglas Spolyar

We show that the QCD axion can drive inflation via a series of tunneling events. For axion models with a softly broken $Z_N$ symmetry, the axion potential has a series of $N$ local minima and may be modeled by a tilted cosine. Chain inflation results along this tilted cosine: the field tunnels from an initial minimum near the top of the potential through a s

V. Barger, Patrick Huber, Danny Marfatia

We propose that the solar neutrino deficit may be due to oscillations of mass-varying neutrinos (MaVaNs). This scenario elucidates solar neutrino data beautifully while remaining comfortably compatible with atmospheric neutrino and K2K data and with reactor antineutrino data at short and long baselines (from CHOOZ and KamLAND). We find that the survival prob

Daniel Caro

Let $k$ be a perfect field of characteristic $p >0$, $U$ be a variety over $k$ and $F$ be a power of Frobenius. We construct the category of overholonomic arithmetical ($F$-)$\D$-modules over $U$ and the category of overholonomic ($F$-)complexes over $U$. We prove that overholonomic complexes over $U$ are stables by direct images, inverse images, extraordina

D. Reichart, M. Nysewander, J. Moran, J. Bartelme

Funded by $1.2M in grants and donations, we are now building PROMPT at CTIO. When completed in late 2005, PROMPT will consist of six 0.41-meter diameter Ritchey-Chretien telescopes on rapidly slewing mounts that respond to GRB alerts within seconds, when the afterglow is potentially extremely bright. Each mirror and camera coating is being optimized for a di

P. B. Cameron, P. Chandra, A. Ray, S. R. Kulkarni

Over a decade ago it was established that the remarkable high energy transients, known as soft gamma-ray repeaters (SGRs), are a Galactic population and originate from neutron stars with intense (<~ 10^15 G) magnetic fields (&#34;magnetars&#34;). On 27 December 2004 a giant flare (fluence >~ 0.3 erg/cm^2) was detected from SGR 1806-20. Here we report the dis

F. del Aguila, J. A. Aguilar-Saavedra, A. Martinez de la Ossa, D. Meloni

We analyse l W nu production at ILC, paying special attention to the role of the final lepton flavour and beam polarisation in the search for a new heavy neutrino N. We show that a sizeable coupling to the electron V_eN ~ 10^-2 is necessary to have an observable signal in any of the channels, despite the fact that the signal may be more visible in muon or ta

Parampreet Singh

Modification to the behavior of geometrical density at short scales is a key result of loop quantum cosmology, responsible for an interesting phenomenology in the very early universe. We demonstrate the way matter with arbitrary scale factor dependence in Hamiltonian incorporates this change in its effective dynamics in the loop modified phase. For generic m

Kishore T. Kapale, Girish S. Agarwal, Marlan O. Scully

Interactions among qubits are essential for performing two-qubit quantum logic operations. However, nature gives us only nearest neighbor interactions in simple and controllable settings. Here we propose a strategy to induce interactions among two atomic entities that are not necessarily neighbors of each other through their common coupling with a cavity fie

L. R. Ribeiro, Claudio Furtado, J. R. Nascimento

In this letter we study the quantum dyamics of a neutral particle in the presence of an external magnetic field. We demonstrate in a specific field-dipole configuration that we have a quantization similar to the Landau Levels. We investigate this quantization motivated by the recent analysis of Landau-Aharonov-Casher(LAC) quantization of Ericsson and Sjöqvis

Anthony Challinor, Antony Lewis

Weak lensing of the CMB changes the unlensed temperature anisotropy and polarization power spectra. Accounting for the lensing effect will be crucial to obtain accurate parameter constraints from sensitive CMB observations. Methods for computing the lensed power spectra using a low-order perturbative expansion are not good enough for percent-level accuracy.

Duc Phuong Nguyen, Nicolas Regnault, Robson Ferreira, Gerald Bastard

The electronic continuum states of InAs/GaAs semiconductor quantum dots embedded in a GaAs/AlAs superlattice are theoretically investigated and the far infrared absorption spectra are calculated for a variety of structures and polarizations. The effect of a strong magnetic field applied parallel to the growth direction is also investigated. We predict that t

Juri Poutanen, Boris E. Stern

We discuss here constraints on the particle acceleration models from the observed gamma-ray bursts spectra. The standard synchrotron shock model assumes that some fraction of available energy is given instantaneously to the electrons which are injected at high Lorentz factor. The emitted spectrum in that case corresponds to the spectrum of cooling electrons,

Luis F. Alday, Justin R. David, Edi Gava, K. S. Narain

We study structure constants of gauge invariant operators in planar N=4 Yang-Mills at one loop with the motivation of determining features of the string dual of weak coupling Yang-Mills. We derive a simple renormalization group invariant formula characterizing the corrections to structure constants of any primary operator in the planar limit. Applying this t

Askar Ibragimov, Juri Poutanen, Marat Gilfanov, Andrzej A. Zdziarski

We present the results of spectral analysis of 42 simultaneous broad-band Ginga--OSSE and RXTE--OSSE observations of Cyg X-1 carried out in 1991 and 1996--1999. The hardest spectra in our sample in the energy range from 3 to \~1000 keV can be well described by thermal Comptonization model with reflection from the cold disc, while the rest of the spectra are

A. M. M. Pruisken, R. Shankar, Naveen Surendran

We introduce the concept of super universality in quantum Hall and spin liquids which has emerged from previous studies. It states that all the fundamental features of the quantum Hall effect are generically displayed as general topological features of the $θ$ parameter in nonlinear sigma models in two dimensions. To establish super universality in spin liqu

E. N. E. van Dalen, C. Fuchs, Amand Faessler

The momentum and isospin dependence of the in-medium nucleon mass are studied. Two definitions of the effective mass, i.e. the Dirac mass $m^*_D$ and the nonrelativistic mass $m^*_{NR}$ which parameterizes the energy spectrum, are compared. Both masses are determined from relativistic Dirac-Brueckner-Hartree-Fock calculations. The nonrelativistic mass shows

A. P. Krutenkova, T. Watanabe, D. Abe, Y. Fujii

The forward inclusive pion double charge exchange reaction, ^{16}O(pi^-,pi^+)X, at T_0 = 0.50 and 0.75 GeV has been studied in the kinematical region where an additional pion production is forbidden by energy-momentum conservation. The experiment was performed with the SKS spectrometer at KEK PS. The measured ratio of double charge exchange cross-section for

P. Yu. Popov, A. D. Smirnov

The rare t-quark decays $t \to c l_j^{+} l_k^{-}$, $t \to c \tilde{ν_j} ν_k$ via the scalar leptoquark doublets are investigated in the minimal four color symmetry model with the Higgs mechanism of the quark-lepton mass splitting. The partial widths of these decays are calculated and the total width of the charged lepton mode $ Γ(t \to c {l^{+}}&#39; l^{-})=

S. Mereghetti, A. Tiengo, P. Esposito, D. Gotz

The low energy (<10 keV) X-ray emission of the Soft Gamma-ray Repeater SGR1806-20 has been studied by means of four XMM-Newton observations carried out in the last two years, the latter performed in response to a strong sequence of hard X-ray bursts observed on 2004 October 5. The source was caught in different states of activity: over the 2003-2004 period t

L. Zamick, A. Escuderos

We address the problem, previously considered by Ginocchio and Haxton (G-H), of the number of states for three identical particles in a single j-shell with angular momentum J=j. G-H solved this problem in the context of the quantum Hall effect. We address it in a more direct way. We also consider the case J=j+1 to show that our method is more general, and we

Henry K. Schenck, Alexander I. Suciu

If \A is a complex hyperplane arrangement, with complement X, we show that the Chen ranks of G=π_1(X) are equal to the graded Betti numbers of the linear strand in a minimal, free resolution of the cohomology ring A=H^*(X,\k), viewed as a module over the exterior algebra E on \A: θ_k(G) = \dim_\k Tor^E_{k-1}(A,\k)_k, where \k is a field of characteristic 0,

M. Zemcov, M. Halpern, E. Pierpaoli

The Sub-millimetre Common User Bolometer Array (SCUBA) at the JCMT employs a chopping and nodding observation technique to remove variations in the atmospheric signal and improve the long term stability of the instrument. In order to understand systematic effects in SCUBA data, we have analysed single-nod time streams from across SCUBA&#39;s lifetime, and pr

Pau Amaro-Seoane

This thesis embraces several aspects of theoretical stellar dynamics in clusters, both analytically and numerically. We try to elucidate the phenomena currently observed in all types of galaxies, including AGNs and quasars, some of the most powerful objects in the universe. The interactions between the stellar system and the central black hole give rise to a

Takahiro Harada, Shin-ichi Sasa

In systems driven away from equilibrium, the velocity correlation function and the linear response function to a small perturbation force do not satisfy the fluctuation-response relation (FRR) due to the lack of detailed balance in contrast to equilibrium systems. In this Letter, an equality between an extent of the FRR violation and the rate of energy dissi

Adam Krawiec, Marek Szydlowski, Wlodzimierz Godlowski

We study metric-affine gravity (MAG) inspired cosmological models. Those models were statistically estimated using the SNIa data. We also use the cosmic microwave background observations and the big-bang nucleosynthesis analysis to constrain the density parameter $Ω_{ψ,0}$ which is related to the non-Riemannian structure of the underlying spacetime. We argue

Lara Faoro, Francesco A. Raffa, Mario Rasetti

We give a formal algebraic description of Josephson-type quantum dynamical systems, i.e., Hamiltonian systems with a cos theta-like potential term. The two-boson Heisenberg algebra plays for such systems the role that the h(1) algebra does for the harmonic oscillator. A single Josephson junction is selected as a representative of Josephson systems. We constr

Makoto Sakaguchi, Yukinori Yasui

The geometry of five-dimensional Kerr black holes is discussed based on geodesics and Weyl curvatures. Kerr-Star space, Star-Kerr space and Kruskal space are naturally introduced by using special null geodesics. We show that the geodesics of AdS Kerr black hole are integrable, which generalizes the result of Frolov and Stojkovic. We also show that five-dimen

S. Albino, B. A. Kniehl, G. Kramer

We present new sets of next-to-leading order fragmentation functions describing the production of charged pions, kaons and protons from the gluon and from each of the quarks, obtained by fitting to all relevant data sets from e+ e- annihilation. The individual light quark flavour fragmentation functions are obtained phenomenologically for the first time by i

D. Dudal, R. F. Sobreiro, S. P. Sorella, H. Verschelde

The local composite operator A^2 is added to the Zwanziger action, which implements the restriction to the Gribov region in Euclidean Yang-Mills theories in the Landau gauge. We prove the renormalizability of this action to all orders of perturbation theory. This allows to study the dimension two gluon condensate <A^2> by the local composite operator formali

Alberto Anfossi, Paolo Giorda, Arianna Montorsi, Fabio Traversa

We analyze correlations between subsystems for an extended Hubbard model exactly solvable in one dimension, which exhibits a rich structure of quantum phase transitions (QPTs). The T=0 phase diagram is exactly reproduced by studying singularities of single-site entanglement. It is shown how comparison of the latter quantity and quantum mutual information all

A. M. Lionetto, A. Morselli, V. Zdravkovic

We studied the variation of $e^+$ and $\bar p$ top of the atmosphere spectra due to the parameters uncertainties of the Milky Way geometry, propagation models and cross sections. We used the B/C data and Galprop code for the propagation analysis. We also derived the uncertainty bands for subFe/Fe ratio, H and He. Finally, we considered a neutralino induced c

J. Zimanyi, P. Levai, T. S. Biro

We describe the hadronization of quark matter assuming that quarks creating hadrons coalesce from a continuous mass distribution. The pion and antiproton spectrum as well as the momentum dependence of the antiproton to pion ratio are calculated. This model reproduces fairly well the experimental data at RHIC energies.

Vicente Garzo

A linear stability analysis of the hydrodynamic equations with respect to the homogeneous cooling state is carried out to identify the conditions for stability as functions of the wave vector, the dissipation, and the density. In contrast to previous studies, this description is based on the results derived from the Enskog equation for inelastic hard spheres

A. Bialas, R. Peschanski

We consider a version of QCD dipole cascading corresponding to a finite number n of discrete steps Delta Y of branching in rapidity. The discretization scheme preserving the holomorphic factorizability and scale-invariance in position space of the dipole splitting function, we derive an exact recurrence formula from step to step which plays the role of a ``d

Domenico Marinucci

In this paper we study the asymptotic behavior of the angular bispectrum of spherical random fields. Here, the asymptotic theory is developed in the framework of fixed-radius fields, which are observed with increasing resolution as the sample size grows. The results we present are then exploited in a set of procedures aimed at testing non-Gaussianity; for th

Man-Wai Ho

A class of random hazard rates, which is defined as a mixture of an indicator kernel convolved with a completely random measure, is of interest. We provide an explicit characterization of the posterior distribution of this mixture hazard rate model via a finite mixture of S-paths. A closed and tractable Bayes estimator for the hazard rate is derived to be a

G. Takeda, F. A. Rasio

One of the most remarkable properties of extrasolar planets is their high orbital eccentricities. Observations have shown that at least 20% of these planets, including some with particularly high eccentricities, are orbiting a component of a wide binary star system. The presence of a distant binary companion can cause significant secular perturbations to the

Jia-Feng Chang, You-Gen Shen

Using the Pöshl-Teller approximation, we evaluate the neutrino quasinormal modes (QNMs) of a Kerr-Newman-de Sitter black hole. The result shows that for a Kerr-Newman-de Sitter black hole, massless neutrino perturbation of large $Λ$, positive $m$ and small value of $n$ will decay slowly.

N. Beisert, A. A. Tseytlin, K. Zarembo

We compare quantum corrections to semiclassical spinning strings in AdS(5)xS(5) to one-loop anomalous dimensions in N=4 supersymmetric gauge theory. The latter are computed using the reduced (Landau-Lifshitz) sigma model and with the help of the Bethe ansatz. The results of all three approaches are in remarkable agreement with each other. As a byproduct we e

Sungmin Lee, Yup Kim

We investigate Bak-Sneppen coevolution models on scale-free networks with various degree exponents $γ$ including random networks. For $γ>3$, the critical fitness value $f_c$ approaches to a nonzero finite value in the limit $N \to \infty$, whereas $f_c$ approaches to zero as $2<γ\le 3$. These results are explained by showing analytically $f_c(N) \simeq A/<(k

Yong Zhou

We strictly define two set Wave-function Renormalization Constants (WRC) under the LSZ reduction formula for unstable particles at the first time. Then by introducing antiparticle&#39;s WRC and the CPT conservation law we obtain a new wave-function renormalization condition which can be used to totally determine the two set WRC. We calculate two physical pro

Hidefumi Nomura, Shijun Yoshida, Makoto Tanabe, Kei-ichi Maeda

We study the evolution of a five-dimensional rotating black hole emitting scalar field radiation via the Hawking process for arbitrary initial values of the two rotation parameters $a$ and $b$. It is found that any such black hole whose initial rotation parameters are both nonzero evolves toward an asymptotic state $a/M^{1/2}=b/M^{1/2}={\rm const}(\neq 0)$,

Gabriele Scheler

We present an unsupervised, local activation-dependent learning rule for intrinsic plasticity (IP) which affects the composition of ion channel conductances for single neurons in a use-dependent way. We use a single-compartment conductance-based model for medium spiny striatal neurons in order to show the effects of parametrization of individual ion channels

Joseph F. Johnson

We derive the probabilities of measurement results from Schroedinger&#39;s equation plus a definition of macroscopic as a particular kind of thermodynamic limit. Bohr&#39;s insight that a measurement apparatus must be classical in nature and classically describable is made precise in a mathematical sense analogous to the procedures of classical statistical m

I. O. Vakarchuk

A new method is proposed for the calculation of full density matrix and thermodynamic functions of a many-boson system. Explicit expressions are obtained in the pair correlations approximation for an arbitrary temperature. The theory is self-consistent in the sence that the calculated properties at low temperatures coincide with that of Bogoliubov theory and

Zai-Zhe Zhong

In this paper we prove that every pure-state $Ψ^{(N)}$ of N (N$\geqslant 3)$ continuous variables corresponds to a pair of convex rigid covers (CRCs) structures in the continuous-dimensional Hilbert-Schmidt space. Next we strictly define what are the partial separability and ordinary separability, and discuss how to use CRCs to describe various separability.

Scott Aaronson

Can NP-complete problems be solved efficiently in the physical universe? I survey proposals including soap bubbles, protein folding, quantum computing, quantum advice, quantum adiabatic algorithms, quantum-mechanical nonlinearities, hidden variables, relativistic time dilation, analog computing, Malament-Hogarth spacetimes, quantum gravity, closed timelike c

Randall W. Hall

A kink-based path integral method, previously applied to atomic systems, is modified and used to study molecular systems. The method allows the simultaneous evolution of atomic and electronic degrees of freedom. Results for CH$_4 $, NH$_3 $, and H$_2 $O demonstrate this method to be accurate for both geometries and energies. Comparison with DFT and MP2 level

A. Akindinov, V. Golovin, A. Martemiyanov, V. Petrov

Time of flight of a minimum ionizing particle along a fixed base has been measured with a 100 ps accuracy by means of a Dielectric Resistive Plate Chamber (DRPC) with 4 x 0.3 mm gas gaps. DRPC timing characteristics have been studied with different applied voltages, discriminating thresholds and beam intensities. It may be stated that the time-of-flight reso

V. A. Kuz&#39;menko

The experimental proofs of strong time invariance violation in optics are discussed. Time noninvariance is the only real physical base for explanation the origin of the most phenomena in nonlinear optics. The experimental study of forward and reversed transitions in oriented in uniform electric field molecules is proposed.

Zhong-Qi Ma, Bo-Wei Xu

An exact quantization rule for the Schrödinger equation is presented. In the exact quantization rule, in addition to $Nπ$, there is an integral term, called the quantum correction. For the exactly solvable systems we find that the quantum correction is an invariant, independent of the number of nodes in the wave function. In those systems, the energy levels

Li-Bin Fu, Shi-Gang Chen

For classical Hamiltonian systems, the adiabatic condition may fail at some critical points. However, the breakdown of the adiabatic condition does not always make the adiabatic evolution be destroyed. In this paper, we suggest a supplemental condition of the adiabatic evolution for the fixed points of classical Hamiltonian systems when the adiabatic conditi

E. L. Bratkovskaya

In this short review the results of detailed studies for dilepton production from $p+A$ and $A+A$ reactions at SIS energies are presented. The calculations are based on a semi-classical BUU transport model that includes the off-shell propagation of vector mesons and evaluates the width of the vector mesons dynamically. Different scenarios of in-medium modifi

H. Lenske, P. Kienle

We propose to use antiprotons to investigate the sizes of stable and neutron-rich exotic nuclei by measurements of the $\pbar A$ absorption cross section along isotopic chains in inverse kinematics. The expected effects are studied theoretically in a microscopic model. The $\pbar U$ optical potentials are obtained by folding free space $\pbar N$ scattering a

A. Blazkiewicz, V. E. Oberacker, A. S. Umar, M. Stoitsov

We solve the Hartree-Fock-Bogoliubov (HFB) equations for deformed, axially symmetric even-even nuclei in coordinate space on a 2-D lattice utilizing the Basis-Spline expansion method. Results are presented for the neutron-rich zirconium isotopes up to the two-neutron dripline. In particular, we calculate binding energies, two-neutron separation energies, nor

N. Jachowicz, K. Vantournhout, J. Ryckebusch, K. Heyde

We study neutrino-induced nucleon knockout off atomic nuclei and examine the polarization properties of the ejectile. A detailed study of the spin dependence of the outgoing nucleon is presented. The numerical results are derived within a non-relativistic plane-wave impulse-approximation approach. Our calculations reveal large polarization asymmetries, and c

Dao T. Khoa, Hoang Sy Than

A consistent folding analysis of the elastic p(6He,6He)p scattering and charge exchange p(6He,6Li*)n reaction data measured at Elab=41.6A MeV has been performed within the coupled channels formalism. We have used the isovector coupling to link the isospin dependence of 6He+p optical potential to the cross section of p(6He,6Li*)n reaction exciting the 0+ isob

N. Olver, I. V. Barashenkov

We present a new vorticity-raising transformation for the second integrable complexification of the sine-Gordon equation on the plane. The new transformation is a product of four Schlesinger maps of the Painlevé-V to itself, and allows a more efficient construction of the $n$-vortex solution than the previously reported transformation comprising a product of

Y. Kodama, B. Konopelchenko, L. Martinez Alonso, E. Medina

A general scheme for determining and studying hydrodynamic type systems describing integrable deformations of algebraic curves is applied to cubic curves. Lagrange resolvents of the theory of cubic equations are used to derive and characterize these deformations.

Uriel Frisch, Jeremie Bec, Erik Aurell

In his first 1941 paper Kolmogorov assumed that the velocity has increments which are homogeneous and independent of the velocity at a suitable reference point. This assumption of local homogeneity is consistent with the nonlinear dynamics only in an asymptotic sense when the reference point is far away. The inconsistency is illustrated numerically using the

Ilwoo Cho

In [15] and [16], we constructed a graph W*-probability space over its diagonal subalgebra. To study this strudture is a good example of Speicher&#39;s amalgamated W*-probability spaces. In this paper, we will observe the diagonal compressed random variables. we will compute the moments and cumulants of them and we will show that the freeness on diagonal com

Pierre Tisseur

Given a new definition for the entropy of a cellular automata acting on a two-dimensional space, we propose an inequality between the entropy of the shift on a two-dimensional lattice and some angular analog of Lyapunov exponents.

Remke Kloosterman

We prove that the elliptic surface y^2=x^3+2(t^8+14t^4+1)x+4t^2(t^8+6t^4+1) has geometric Mordell-Weil rank 15. This completes a list of Kuwata, who gave explicit examples of elliptic K3-surfaces with geometric Mordell-Weil rank 0,1,..., 14, 16, 17,18.

Ensil Kang, J. Hyam Rubinstein

This is the second in a series of papers in which we investigate ideal triangulations of the interiors of compact 3-manifolds with tori or Klein bottle boundaries. Such triangulations have been used with great effect, following the pioneering work of Thurston. Ideal triangulations are the basis of the computer program SNAPPEA of Weeks and the program SNAP of