February 2009 arXiv papers — page 5

J. M. Miller, M. Nowak, K. Nandra, W. N. Brandt

Disk accretion may be the fundamental astrophysical process. Stars and planets form through the accretion of gas in a disk. Black holes and galaxies co-evolve through efficient disk accretion onto the central supermassive black hole. Indeed, approximately 20 percent of the ionizing radiation in the universe is supplied by disk accretion onto black holes. And

AAS WGLA, :, Nancy Brickhouse, John Cowan

As the Galaxies across Cosmic Time (GCT) panel is fully aware, the next decade will see major advances in our understanding of these areas of research. To quote from their charge, these advances will occur in studies of the formation, evolution, and global properties of galaxies and galaxy clusters, as well as active galactic nuclei and QSOs, mergers, star f

David Schlegel, Martin White, Daniel Eisenstein

BOSS, the Baryon Oscillation Spectroscopic Survey, is a 5-year program to measure the absolute cosmic distance scale and expansion rate with percent-level precision at redshifts z<0.7 and z~2.5. BOSS uses the &#34;standard ruler&#34; provided by baryon acoustic oscillations (BAO). BOSS will achieve a near optimal measurement of the BAO scale at z<0.7, with a

J. M. Miller, P. Uttley, K. Nandra, D. Barret

If a black hole has a low spin value, it must double its mass to reach a high spin parameter. Although this is easily accomplished through mergers or accretion in the case of supermassive black holes in galactic centers, it is impossible for stellar-mass black holes in X-ray binaries. Thus, the spin distribution of stellar-mass black holes is almost pristine

D. J. Priour

We derive and discuss a technique for manipulating power series which is complementary to standard procedures. We begin with the translation operator, but we express the operator as an infinite product instead of expanding it as a series and we apply combinatorial arguments to generate the terms in the series in an efficient manner with a minimum of clutter

Paul de Medeiros, José Figueroa-O&#39;Farrill, Elena Méndez-Escobar, Patricia Ritter

We prove a structure theorem for finite-dimensional indefinite-signature metric 3-Lie algebras admitting a maximally isotropic centre. This algebraic condition indicates that all the negative-norm states in the associated Bagger-Lambert theory can be consistently decoupled from the physical Hilbert space. As an immediate application of the theorem, new examp

K. Nakayama, Yongseok Oh, H. Haberzettl

The production of $η$ and $η^\prime$ mesons in photon- and hadron-induced reactions are studied in a combined analysis based on an effective Lagrangian approach in order to learn about the relevant production mechanisms and the possible role of nucleon resonances in these reactions.

Julia C. Lee, Randall K. Smith, C. R. Canizares, E. Costantini

The abundances of gas and dust (solids and complex molecules) in the interstellar medium (ISM) as well as their composition and structures impact practically all of astrophysics. Fundamental processes from star formation to stellar winds to galaxy formation all scale with the number of metals. However, significant uncertainties remain in both absolute and re

AAS WGLA, :, Nancy Brickhouse, John Cowan

As the Cosmology and Fundamental Physics (CFP) panel is fully aware, the next decade will see major advances in our understanding of these areas of research. To quote from their charge, these advances will occur in studies of the early universe, the microwave background, the reionization and galaxy formation up to virialization of protogalaxies, large scale

L. Bravina, K. Tywoniuk, A. Capella, E. G. Ferreiro

Experiments with gold-gold collisions at RHIC have revealed (i) stronger suppression of charmonium production at forward rapidity than at midrapidity and (ii) the similarity between the suppression degrees at RHIC and SPS energies. To describe these findings we employ the model that includes nuclear shadowing effects, calculated within the Glauber-Gribov the

Amelia Sparavigna

Instead of evaluating the gradient field of the brightness map of an image, we propose the use of dipole vectors. This approach is obtained by adapting to the image gray-tone distribution the definition of the dipole moment of charge distributions. We will show how to evaluate the dipoles and obtain a vector field, which can be a good alternative to the grad

A. M. Ghezelbash

We investigate the recently proposed Kerr/CFT correspondence in the context of rotating spacetimes with a NUT twist. The Kerr/CFT correspondence states that the near-horizon states of an extremal four (or higher) dimensional black hole could be identified with a certain chiral conformal field theory. The corresponding Virasoro algebra is generated with a cla

Matjaz Perc

We study the evolution of cooperation in the prisoner&#39;s dilemma and the snowdrift game on scale-free networks that are subjected to intentional and random removal of vertices. We show that, irrespective of the game type, cooperation on scale-free networks is extremely robust against random deletion of vertices, but declines fast if vertices with the maxi

Eric Brown, Guenter Ahlers

Previously we published a dynamical model (E. Brown and G. Ahlers, Phys. Fluids, 20, 075101 (2008)) for the large-scale-circulation (LSC) dynamics of Rayleigh-Benard convection in cylindrical containers. The model consists of a pair of stochastic ordinary differential equations, motivated by the Navier-Stokes equations, one each for the strength delta and th

Dmitry Zinoviev, Vy Duong

All major on-line social networks, such as MySpace, Facebook, LiveJournal, and Orkut, are built around the concept of friendship. It is not uncommon for a social network participant to have over 100 friends. A natural question arises: are they all real friends of hers, or does she mean something different when she calls them &#34;friends?&#34; Speaking in ot

Andre de Gouvea

In this talk I review what we know and don&#39;t know about neutrinos, neutrino masses and lepton mixing. I also discuss the importance of the discovery that neutrinos have nonzero masses, and illustrate how little is currently known about the physics behind them.

Alexei Iantchenko

We consider semi-classical Schr{ö}dinger operator $ P(h)=-h^2Δ+V(x)$ in ${\mathbb R}^n$ such that the analytic potential $V$ has a non-degenerate critical point $x_0=0$ with critical value $E_0$ and we can define resonances in some fixed neighborhood of $E_0$ when $h>0$ is small enough. If the eigenvalues of the Hessian are $\zz$-independent the resonances i

Rafael Ramirez, Natalia Sadovskaia

We extend the Eruguin result exposed in the paper &#34;Construction of the whole set of ordinary differential equations with a given integral curve&#34; published in 1952 and construct a differential system in $\Bbb{R}^N$ which admits a given set of the partial integrals, in particular we study the case when theses functions are polynomials. We construct a n

Jeetain Mittal, Robert B. Best

We investigate the effect of macromolecular crowding on protein folding, using purely repulsive crowding particles and a self-organizing polymer model of protein folding. We find that the thermodynamics of folding for typical alpha-, beta- and alpha/beta-proteins are well described by an adaptation of the scaled particle theory (SPT). In this approach, the n

Yifan Liang, Andrea Goldsmith, Michelle Effros

We consider transmission of stationary and ergodic sources over non-ergodic composite channels with channel state information at the receiver (CSIR). Previously we introduced alternate capacity definitions to Shannon capacity, including the capacity versus outage and the expected capacity. These generalized definitions relax the constraint of Shannon capacit

V. N. Velizhanin

We present the result of a full direct component calculation for the non-planar contribution to the four-loop anomalous dimension of the Konishi operator in N =4 Supersymmetric Yang-Mills theory. The result contains only zeta(5) term and is proportional to zeta(5) contribution in the planar case, which comes purely from wrapping corrections. We have extended

Homin Shin, Gregory M. Grason, Christian D. Santangelo

Soft spheres interacting via a hard core and range of attractive and repulsive "soft-shoulder" potentials self-assemble into clusters forming a variety of mesophases. We combine a mean field theory developed from a lattice model with a level surface analysis of the periodic structures of soft-sphere aggregates to study stable morphologies for all clustering

J. M. Carmona, J. L. Cortes, J. Indurain, D. Mazon

A reinterpretation of noncommutativity as a mapping of paths is proposed at the level of quantum mechanics.

Matthew Carlton

We provide a detailed analysis of the doubly spinning black ring, investigating both its general properties and its shape. We also examine the geometry of the ergosurface, illustrating the process of self-merging and discussing the physics of ergoregions.

Gabriel Cardona, Merce Llabres, Francesc Rossello, Gabriel Valiente

In a previous work, we gave a metric on the class of semibinary tree-sibling time consistent phylogenetic networks that is computable in polynomial time; in particular, the problem of deciding if two networks of this kind are isomorphic is in P. In this paper, we show that if we remove the semibinarity condition above, then the problem becomes much harder. M

Andrea Aiello, Christoph Marquardt, Gerd Leuchs

We describe a novel phenomenon occurring when a polarized Gaussian beam of light is observed in a Cartesian reference frame whose axes are not parallel to the direction of propagation of the beam. Such phenomenon amounts to an intriguing spin-dependent shift of the position of the center of the beam, with manners akin to the spin Hall effect of light. We dem

Alexander López, Ernesto Medina, Nelson Bolívar, Bertrand Berche

In a recent paper [Phys. Rev. Lett. 101, 106601], I. V. Tokatly addresses a non Abelian formulation of spin orbit interaction in condensed matter, restricting to a gauge symmetric scenario. In this comment we draw attention on the relevance of gauge symmetry breaking on such formulation and point out why this is a necessary ingredient for properly describing

L. G. Sarasua, A. Moreno-Gobbi, M. A. Continentino

In this work we study the Double Exchange-Holstein (DE-H) model with an electron-phonon interaction $γ$ coupled to magnetism. The analysis is performed combining a mean-field approximation for the double exchange interaction and the Lang-Firsov transformation for the electron-phonon interaction. Discontinuous magnetic transitions appear when the dependence o

Robert J. Harris, Alan M. Levine, Martin Durant, Albert K. H. Kong

Results of observations of the Galactic bulge X-ray source GX 9+9 by the All-Sky Monitor (ASM) and Proportional Counter Array (PCA) onboard the Rossi X-ray Timing Explorer are presented. The ASM results show that the 4.19 hour X-ray periodicity first reported by Hertz and Wood in 1987 was weak or not detected for most of the mission prior to late 2004, but t

Israel Felner, Yakov Kopelevich

Magnetization M(T,H) measurements performed on thoroughly characterized commercial amorphous carbon powder doped with sulfur (AC-S), revealed the occurrence of an inhomogeneous superconductivity (SC) below T_c = 38 K. The constructed magnetic field-temperature (H-T) phase diagram resembles that of type-II superconductors. However, AC-S demonstrates a number

Barry F. Madore, Erica Nelson, Kristen Petrillo

We present a catalog and imaging atlas of classical (collisional) RING galaxies distilled from the Arp-Madore Atlas of Southern Peculiar Galaxies and Associations and supplemented with other known RING galaxies from the published literature. The catalog lists the original host object, compiles available redshifts and presents newly determined positions for t

T. M. Aliev, A. Ozpineci, M. Savci

The magnetic and quadrupole moments of the light-vector and axial-vector mesons are calculated in the light cone QCD sum rules. Our results for the static properties of these mesons are compared with the predictions of lattice QCD as well as other approaches existing in the literature.

Floriana Giannuzzi

The spectrum of baryons with two heavy quarks is predicted, assuming a configuration of a light quark and a heavy diquark. The masses are computed within a semirelativistic quark model, using a potential obtained in the framework of the AdS/QCD correspondence. All the parameters defining the model are determined fitting the meson spectrum. The obtained mass

Gad Eilam

We discuss the rare decay of the top quark into a pair of same charge leptons (with identical or different flavors), a b quark and a (real or virtual) W-. The above process proceeds only if the exchanged neutrino N is of the Majorana type. This decay is the neutrinoless double b decay of the top. We find measurable values for its rate at the LHC with luminos

Pei Zhao, Jing Guo

A computationally efficient mode space simulation method for atomistic simulation of a graphene nanoribbon field-effect transistor in the ballistic limits is developed. The proposed simulation scheme, which solves the nonequilibrium Green&#39;s function coupled with a three dimensional Poisson equation, is based on the atomistic Hamiltonian in a decoupled mo

T. N. Venkataramana, B. Speh

We show that complementary series representations of SO(n,1) contain discretely complementary series of SO(m,1) provided the continuous parameter is sufficiently close to the first point of reducibility and the representation of the compact part of the Levi is a sufficiently small fundamental representation. We prove as a consequence that cohomological repre

Tobias Berger

By adapting the work of Kudla and Millson we obtain a lifting of cuspidal cohomology classes for the symmetric space associated to GO(V) for an indefinite rational quadratic space V of even dimension to holomorphic Siegel modular forms on GSp_n(A). For n=2 we prove Thom&#39;s Lemma for hyperbolic 3-space, which together with results of Kudla and Millson impl

Bernhard Kroetz, Ray Kunze, Robert J. Stanton

In this paper we determine the Bochner measure for spherical functions on a semi-simple Lie group of rank one.

Pei Zhao, Jyotsna Chauhan, Jing Guo

Tunneling field-effect transistors (FETs) have been intensely explored recently due to its potential to address power concerns in nanoelectronics. The recently discovered graphene nanoribbon (GNR) is ideal for tunneling FETs due to its symmetric bandstructure, light effective mass, and monolayer-thin body. In this work, we examine the device physics of p-i-n

Z. Bagoly, L. Borgonovo, I. Horvath, A. Meszaros

A sample of 197 long BATSE GRBs is studied statistically. In the sample 11 variables, describing for any burst the time behavior of the spectra and other quantities, are collected. The application of the factor analysis on this sample shows that five factors describe the sample satisfactorily. Both the pseudo-redshifts coming from the variability and the Ama

U. Munari, A. Siviero, M. Graziani, A. Maitan

We carried out a VRI photometric monitoring of StHa 55, and in addition we obtained low resolution absolute spectro-photometry and high resolution Echelle spectroscopy. Our data show that StHa 55 is a carbon Mira, pulsating with a 395 day period, with <V>=13.1 mean brightness and 2.8 mag amplitude in V band. It suffers from a low reddening (E(B-V)=0.15), lie

Kazufumi Kimoto

The quantum $α$-determinant is defined as a parametric deformation of the quantum determinant. We investigate the cyclic $\mathcal{U}_q(\mathfrak{sl}_2)$-submodules of the quantum matrix algebra $\mathcal{A}_q(\mathrm{Mat}_2)$ generated by the powers of the quantum $α$-determinant. For such a cyclic module, there exists a collection of polynomials which desc

George Pal, Yaroslav Pavlyukh, Hans Christian Schneider, Wolfgang Huebner

A novel approach for GW-based calculations of quasiparticle properties for finite systems is presented, in which the screened interaction is obtained directly from a linear response calculation of the density-density correlation function. The conserving nature of our results is shown by explicit evaluation of the $f$-sum rule. As an application, energy renor

A. Henden, U. Munari

We present a multi-epoch, accurate UBVRcIc photometric catalog of 83 symbiotic stars and related objects, measured while calibrating the Henden and Munari (2000, 2001, 2006) photometric sequences around them. The vast majority of the observations where collected in the time interval between October 19, 1998 to April 21, 2002 with the 1.0-m Ritchey-Chretien t

James DiGuglielmo, Chris Messenger, Jaromir Fiurasek, Boris Hage

We apply a Bayesian data analysis scheme known as the Markov Chain Monte Carlo (MCMC) to the tomographic reconstruction of quantum states. This method yields a vector, known as the Markov chain, which contains the full statistical information concerning all reconstruction parameters including their statistical correlations with no a priori assumptions as to

Jeff Cooke, Asantha Cooray, Ranga-Ram Chary, Volker Bromm

The cosmic dark ages are the mysterious epoch during which the pristine gas began to condense and ultimately form the first stars. Although these beginnings have long been a topic of theoretical interest, technology has only recently allowed the beginnings of observational insight into this epoch. Many questions surround the formation of stars in metal-free

E. Zabrodin, I. C. Arsene, J. Bleibel, M. Bleicher

Two microscopic models, UrQMD and QGSM, are used to extract the effective equation of state (EOS) of locally equilibrated nuclear matter produced in heavy-ion collisions at energies from 11.6 AGeV to 160 AGeV. Analysis is performed for the fixed central cubic cell of volume V = 125 fm**3 and for the expanding cell that followed the growth of the central area

Rosario Lo Franco, Giuseppe Compagno, Antonino Messina, Anna Napoli

Extending a previous result on the generation of two-photon generalized binomial field states, here we propose an efficient scheme to generate with high-fidelity, in a single-mode high-Q cavity, N-photon generalized binomial states with a maximum number of photons N>2. Besides their interest for classical-quantum border investigations, we discuss the applica

Titus S. van Erp, Santiago Cuesta-Lopez, Johannes-Geert Hagmann, Michel Peyrard

We show that the calculated DNA denaturation curves for finite (Peyrard-Bishop-Dauxois (PBD) chains are intrinsically undefined.

Maxim Dvornikov

We study low energy quantum oscillations of electron gas in plasma. It is shown that two electrons participating in these oscillations acquire additional negative energy when they interact by means of a virtual plasmon. The additional energy leads to the formation a Cooper pair and possible existence of the superconducting phase in the system. We suggest tha

Oleg Kiselev, Sergei Glebov

We study an initial stage of autoresonant growth of a solution in a dissipative system. We construct an asymptotic formula of an autoresonant germ that is an attractor for autoresonant solutions. We present a moment of a fall and a maximum value of the amplitude for the germ. Numerical simulations are done.

Konstancja Satalecka, Ching-Cheng Hsu, Elisa Bernardini, Giacomo Bonnoli

Because of the short duty-cycles and observation-time constraints, studies of bright TeV (E>100 GeV) blazars are mostly restricted to flaring episodes or rather short (days to few weeks) multiwavelength campaigns. At the same time, long-term studies of these objects are essential to gain a more complete understanding of the blazar phenomenon and to constrain

Olga V. Man'ko

A review of the photon-number tomography and symplectic tomography as examples of star-product quantization is presented. The classical statistical mechanics is considered within the framework of the tomographic representation.

Alireza Akbari, Ilya Eremin, Peter Thalmeier, Peter Fulde

We analyze the influence of unconventional superconductivity on crystalline electric field (CEF) excitations of rare earth ions in novel superconductors. We show that resonant magnetic excitations of the conduction electrons that have been observed in these systems below T$_c$ may result in the formation of the bound state in the 4$f$-electron susceptibility

R. Mittal, S. Rols, M. Zbiri, Y. Su

We report the pressure and temperature dependence of the phonon density-of-states in superconducting Ca0.6Na0.4Fe2As2 (Tc=21 K) and the parent compound CaFe2As2, using inelastic neutron scattering. We observe no significant change in the phonon spectrum for Ca0.6Na0.4Fe2As2 at 295 K up to pressures of 5 kbar. The phonon spectrum for CaFe2As2 shows softening

Raphael Loewy, Bit-Shun Tam

Let $K$ be a proper (i.e., closed, pointed, full convex) cone in ${\Bbb R}^n$. An $n\times n$ matrix $A$ is said to be $K$-primitive if there exists a positive integer $k$ such that $A^k(K \setminus \{0 \}) \subseteq$ int $K$; the least such $k$ is referred to as the exponent of $A$ and is denoted by $γ(A)$. For a polyhedral cone $K$, the maximum value of $γ

M. Combescot, O. Betbeder-Matibet

For half a century, Feynman diagrams have provided an enlightening way of representing many-body effects between elementary fermions and bosons. They however are quite inappropriate to visualize fermion exchanges taking place between a large number of composite quantum particles. We propose to replace them by &#34;Shiva diagrams&#34; for cobosons made of two

Sadegh Jokar, Volker Mehrmann

Three properties of matrices: the spark, the mutual incoherence and the restricted isometry property have recently been introduced in the context of compressed sensing. We study these properties for matrices that are Kronecker products and show how these properties relate to those of the factors. For the mutual incoherence we also discuss results for sums of

Volker Branding, Nadav Drukker

In this paper we present a family of supersymmetric Wilson loops of N=4 supersymmetric Yang-Mills theory in Minkowski space. Our examples focus on curves restricted to hyperbolic submanifolds, H_3 and H_2, of space-time. Generically they preserve two supercharges, but in special cases more, including a case which has not been discussed before, of the hyperbo

Nicolas Monod, Narutaka Ozawa

J. Dixmier asked in 1950 whether every non-amenable group admits uniformly bounded representations that cannot be unitarised. We provide such representations upon passing to extensions by abelian groups. This gives a new characterisation of amenability. Furthermore, we deduce that certain Burnside groups are non-unitarisable, answering a question raised by G

A. N. Panov

We correspond to any factor algebra of the unitriangular Lie algebra with respect to a regular ideal some permutation. In terms of this permutation one can construct a diagram, that allows to calculate index and maximal dimension of coadjoint representation.

A. A. Christou, F. Lewis, P. Roche, Y. Hashimoto

We carried out observations, with five different instruments ranging in aperture from 0.4m to 10m, of the satellites of Uranus during that planet&#39;s 2007 Equinox. Our observations covered specific intervals of time when mutual eclipses and occultations were predicted. The observations were carried out in the near-infrared part of the spectrum to mitigate

U. Schwingenschloegl, C. Schuster

We study the decay of interface induced structural and electronic relaxation effects in epitaxial LaAlO3/SrTiO3 heterostructures. The results are based on first-principles band structure calculations for a multilayer configuration with an ultrathin LaAlO3 layer sandwiched between bulk-like SrTiO3 layers. We carry out the structure optimization for the hetero

James F. Lutsko, Jean Pierre Boon, Patrick Grosfils

The question of whether the Tsallis entropy is Lesche-stable is revisited. It is argued that when physical averages are computed with the escort probabilities, the correct application of the concept of Lesche-stability requires use of the escort probabilities. As a consequence, as shown here, the Tsallis entropy is unstable but the thermodynamic averages are

A. Aitta

Tricritical points separate continuous and discontinuous symmetry breaking transitions. They occur in a variety of physical systems and their mathematical models. A tricritical point is used to determine a liquid-solid phase transition line in the pressure-temperature plane [Aitta, J. Stat. Mech., 2006]. Excellent experimental agreement has been obtained for

Osamu Saeki, Takahiro Yamamoto

We show that for a C^infty stable map of an oriented 4-manifold into a 3-manifold, the algebraic number of singular fibers of a specific type coincides with the signature of the source 4-manifold.

Takuya Ohkubo, Ken&#39;ichi Nomoto, Hideyuki Umeda, Naoki Yoshida

We calculate the evolution of zero-metallicity Population III (Pop III) stars whose mass grows from the initial mass of $\sim 1M_{\odot}$ by accreting the surrounding gases. Our calculations cover a whole evolutionary stages from the pre-main sequence, via various nuclear burning stages, through the final core collapse or pair-creation instability phases. We

Saloua Chettibi, M. Benmohamed

Energy consumption is the most challenging issue in routing protocol design for mobile ad-hoc networks (MANETs), since mobile nodes are battery powered. Furthermore, replacing or recharging batteries is often impossible in critical environments such as in military or rescue missions. In a MANET, the energy depletion of a node does not affect the node itself

L. Spezzi, I. Pagano, G. Marino, G. Leto

We report the outcome of a deep multi-wavelength study of the IC2391 young open cluster. We aim at uncovering new low-mass and sub-stellar members of the cluster and identifying new debris disk objects. A 30*30 square arcmin area in IC 2391 was observed using the wide-field imager at the ESO 2.2m telescope. The completeness limits of the photometry at 3 sigm

Jean-François Marckert, Grégory Miermont

We prove that a uniform, rooted unordered binary tree with $n$ vertices has the Brownian continuum random tree as its scaling limit for the Gromov-Hausdorff topology. The limit is thus, up to a constant factor, the same as that of uniform plane trees or labeled trees. Our analysis rests on a combinatorial and probabilistic study of appropriate trimming proce

Vijay G. Subramanian, Tara Javidi, Somsak Kittipiyakul

In this paper, a many-sources large deviations principle (LDP) for the transient workload of a multi-queue single-server system is established where the service rates are chosen from a compact, convex and coordinate-convex rate region and where the service discipline is the max-weight policy. Under the assumption that the arrival processes satisfy a many-sou

Nigel Boston, Jordan S Ellenberg

In the preceding paper, Calegari and Dunfield exhibit a sequence of hyperbolic 3-manifolds which have increasing injectivity radius, and which, subject to some conjectures in number theory, are rational homology spheres. We prove unconditionally that these manifolds are rational homology spheres, and give a sufficient condition for a tower of hyperbolic 3-ma

Z. Kurucz, M. W. Sørensen, J. M. Taylor, M. D. Lukin

We present a mechanism to protect quantum information stored in an ensemble of nuclear spins in a semiconductor quantum dot. When the dot is charged the nuclei interact with the spin of the excess electron through the hyperfine coupling. If this coupling is made off-resonant it leads to an energy gap between the collective storage states and all other states

O. Waldmann, T. C. Stamatatos, G. Christou, H. U. Güdel

The antiferromagnetic molecular wheel Fe18 of eighteen exchange-coupled Fe(III) ions has been studied by measurements of the magnetic torque, the magnetization, and the inelastic neutron scattering spectra. The combined data show that the low-temperature magnetism of Fe18 is very accurately described by the Neel-vector tunneling (NVT) scenario, as unfolded b

A. J. Barker, G. I. Ogilvie

Tidal friction is thought to be important in determining the long-term spin-orbit evolution of short-period extrasolar planetary systems. Using a simple model of the orbit-averaged effects of tidal friction, we study the evolution of close-in planets on inclined orbits, due to tides. We analyse the effects of the inclusion of stellar magnetic braking by perf

Fabrizio Castellano

A method to solve the problem f(x) = 0 efficiently on any n-dimensional domain Omega under very broad hypoteses is proposed. The position of the root of f, assumed unique, is found by computing the center of mass of an Omega-shaped object having a singular mass density. It is shown that although the mass of the object is infinite, the position of its center

M Colonna

Highlights on the recent research activity, carried out by the Italian Community involved in the &#34;Nuclear Matter and Nuclear Dynamics&#34; field, will be presented.

Olga V. Man&#39;ko

A review of the symplectic tomographic approaches within the framework of star-product quantization is presented. The classical statistical mechanics within the framework of the tomographic representation is considered. The kernels of star-product of functions - symbols of operators in classical and quantum mechanics are presented.

Sebastian Heller

We show that under some non-degeneracy assumption the only submersive harmonic morphism on a conformally flat $3-$sphere is the Hopf fibration. The proof involves an appropriate use the Chern-Simons functional.

Alejandro B. Kolton, Alberto Rosso, Thierry Giamarchi, Werner Krauth

We study the steady state of driven elastic strings in disordered media below the depinning threshold. In the low-temperature limit, for a fixed sample, the steady state is dominated by a single configuration, which we determine exactly from the transition pathways between metastable states. We obtain the dynamical phase diagram in this limit. At variance wi

Udo Schwingenschloegl, Cosima Schuster, Raymond Fresard

We investigate the consequences of the stripe formation in the nickelate La5/3Sr1/3NiO4 for the details of its crystal structure and electronic states. Our data are based on numerical simulations within density functional theory (DFT) and the generalized gradient approximation (GGA). The on-site Coulomb interaction is included in terms of the LDA+U scheme. S

Sebastian Heller

We classify conformally flat Riemannian $3-$manifolds which possesses a free isometric $S^1-$action.

A. J. Barker, G. I. Ogilvie

Tidal friction is thought to be important in determining the long-term spin-orbit evolution of short-period extrasolar planetary systems. Using a simple model of the orbit-averaged effects of tidal friction Eggleton, Kiseleva & Hut (1998), we analyse the effects of the inclusion of stellar magnetic braking on the evolution of such systems. A phase-plane anal

Grzegorz Nowak, Andrzej Niedzielski, Aleksander Wolszczan

Searches for planets around massive stars are essential for developing general understanding of planet formation and evolution of the planetary systems. The main objective of the Pennsylvania - Torun Planet Search is detection of planets around G-K subgiants and giants through precision radial velocity (RV) measurements with iodine absorption cell using HET

T. Stauber, M. I. Vasilevskiy

We study the electronic relaxation in a quantum dot within the polaron approach, by focusing on the {\it reversible} anharmonic decay of longitudinal optical (LO) phonons forming the polaron into longitudinal acoustic (LA) phonons. The coherent coupling between the LO and LA phonons is treated within a mean-field approach. We derive a temperature-dependent i

Steffen Kessler, Reimar Finken, Udo Seifert

We investigate the dynamics of microcapsules in linear shear flow within a reduced model with two degrees of freedom. In previous work for steady shear flow, the dynamic phases of this model, i.e. swinging, tumbling and intermittent behaviour, have been identified using numerical methods. In this paper, we integrate the equations of motion in the quasi-spher

Monika Adamów, Andrzej Niedzielski

As the SALT High Resolution Spectrograph completion is nearing we plan to extend the Pennsylvania-Torun Planets Search (PTPS) with HET to the southern hemisphere. Due to overlap of the skies available for both HET and SALT in the declination range (+10, -10) deg some cooperation and immediate follow up is possible. Here we present, as an example, a $\sim$ 10

M. T. Beltran, F. Massi, R. Lopez, J. M. Girart

Context. IC 1396N is a bright-rimmed cloud associated with an intermediate-mass star-forming region, where a number of Herbig-Haro objects, H2 jet-like features, CO molecular outflows, and millimeter compact sources have been observed. Aims. To study in detail the complex structure of the IC 1396N core and the molecular outflows detected in the region and to

Laurent Bartholdi, Oleg Bogopolski

We prove that the abstract commensurator of a nonabelian free group, an infinite surface group, or more generally of a group that splits appropriately over a cyclic subgroup, is not finitely generated. This applies in particular to all torsion-free word-hyperbolic groups with infinite outer automorphism group and abelianization of rank at least 2. We also co

P. Aniello, A. Ibort, V. Man&#39;ko, G. Marmo

Using the formalism of quantizers and dequantizers, we show that the characters of irreducible unitary representations of finite and compact groups provide kernels for star products of complex-valued functions of the group elements. Examples of permutation groups of two and three elements, as well as the SU(2) group, are considered. The k-deformed star produ

P. M. Williams, S. V. Marchenko, A. P. Marston, A. F. J. Moffat

We present high-resolution infrared (2--18 micron) images of the archetypal periodic dust-making Wolf-Rayet binary system WR140 (HD 193793) taken between 2001 and 2005, and multi-colour (J -- [19.5]) photometry observed between 1989 and 2001. The images resolve the dust cloud formed by WR140 in 2001, allowing us to track its expansion and cooling, while the

Stefano Bianchi, Nuria Fonseca Bonilla, Matteo Guainazzi, Giorgio Matt

We presented CAIXA, a Catalogue of AGN in the XMM-Newton Archive, in Bianchi et al. (2009). It consists of all the radio-quiet X-ray unobscured (N$_\mathrm{H}<2\times10^{22}$ cm$^{-2}$) active galactic nuclei (AGN) observed by XMM-Newton in targeted observations, whose data are public as of March 2007. With its 156 sources, this is the largest catalogue of h

Giuseppe Bimonte

We determine the commutation relations satisfied by the quantized electromagnetic field in the presence of macroscopic dielectrics and conductors, with arbitrary dispersive and dissipative properties. We consider in detail the case of two plane-parallel material slabs, separated by an empty gap, and we show that at all points in the empty region between the

D. V. Alekseevsky, V. Cortés

Let $M$ be a pseudo-Riemannian spin manifold of dimension $n$ and signature $s$ and denote by $N$ the rank of the real spinor bundle. We prove that $M$ is locally homogeneous if it admits more than ${3/4}N$ independent Killing spinors with the same Killing number, unless $n\equiv 1 \pmod 4$ and $s\equiv 3 \pmod 4$. We also prove that $M$ is locally homogeneo

Simona Angela Apostol, Cosmin Catu, Corina Vernic

Understanding the importance that the electronic medical health records system has, with its various structural types and grades, has led to the elaboration of a series of standards and quality control methods, meant to control its functioning. In time, the electronic health records system has evolved along with the medical data change of structure. Romania

Omar Benhar

In recent years, the italian theoretical Nuclear Physics community has played a leading role in the development of a unified approach, allowing for a consistent and fully quantitative description of the nuclear response to electromagnetic and weak probes. In this paper I review the main achievements in both fields, point out some of the open problems, and ou

J. Sanchez Almeida

We describe a scenario for the topology of the magnetic field in penumbrae that accounts for recent observations showing upflows, downflows, and reverse magnetic polarities. According to our conjecture, short narrow magnetic loops fill the penumbral photosphere. Flows along these arched field lines are responsible for both the Evershed effect and the convect

Gabriela Litcanu, Cristian Morales-Rodrigo

In this paper we will focus on a parabolic degenerate system with respect to unknown functions u and w on a bounded domain of the two-dimensional Euclidean space. This system appears as a mathematical model for some biological processes. Global existence and uniqueness of a nonnegative classical Hölder continuous solution are proved. The last part of the pap

Elena V. Sharoyko

We study locally transitive actions of the commutative unipotent group $\Gan$ on a nondegenerate quadric in the projective space $¶^{n+1}$. It is shown that for each $n$ such an action is unique up to isomorphism.

Nikolaos S. Livathinos

One of the most widely used simulation environments for mobile wireless networks is the Network Simulator 2 (NS-2). However NS-2 stores its outcome in a text file, so there is a need for a visualization tool to animate the simulation of the wireless network. The purpose of this tool is to help the researcher examine in detail how the wireless protocol works