April 2008 arXiv papers — page 9

Kenji Yasunaga, Toru Fujiwara

A lower bound on the number of uncorrectable errors of weight half the minimum distance is derived for binary linear codes satisfying some condition. The condition is satisfied by some primitive BCH codes, extended primitive BCH codes, Reed-Muller codes, and random linear codes. The bound asymptotically coincides with the corresponding upper bound for Reed-M

Dmitry A. Abanin, Leonid S. Levitov

For a sample of an arbitrary shape, the dependence of its conductance on the longitudinal and Hall conductivity is identical to that of a rectangle. We use analytic results for a conducting rectangle, combined with the semicircle model for transport coefficients, to study properties of the monolayer and bilayer graphene. A conductance plateau centered at the

Ioannis Chatzigiannakis, Georgios Giannoulis, Paul G. Spirakis

In this work we study the problem of scheduling tasks with dependencies in multiprocessor architectures where processors have different speeds. We present the preemptive algorithm "Save-Energy" that given a schedule of tasks it post processes it to improve the energy efficiency without any deterioration of the makespan. In terms of time efficiency, w

Changrim Ahn, Rafael Nepomechie

We extend the Zamolodchikov-Faddeev algebra for the superstring sigma model on $AdS_{5}\times S^{5}$, which was formulated by Arutyunov, Frolov and Zamaklar, to the case of open strings attached to maximal giant gravitons, which was recently considered by Hofman and Maldacena. We obtain boundary $S$-matrices which satisfy the standard boundary Yang-Baxter eq

Jin-Hong Park, Shigeki Onoda, Naoto Nagaosa, Jung Hoon Han

We propose a variant of the antiferromagnetic XY model on the triangular lattice to study the interplay between the chiral and nematic orders in addition to the magnetic order. The model has a significant bi-quadratic interaction of the planar spins. When the bi-quadratic exchange energy dominates, a large temperature window is shown to exist over which the

Yi Liao

We address in a recent gauge model of unparticles the issues that are important for consistency of a gauge theory, i.e., unitarity and Ward identity of physical amplitudes. We find that non-integrable singularities arise in physical quantities like cross section and decay rate from gauge interactions of unparticles. We also show that Ward identity is violate

K. J. Coakley, J. D. Splett, D. S. Simons

We construct uncertainty intervals for weak Poisson signals in the presence of background. We consider the case where a primary experiment yields a realization of the signal plus background, and a second experiment yields a realization of the background. The data acquisitions times for the background-only experiment,T_bg, and the primary experiment,T, are se

G. Chardin

The intimate links between gravitation and the second law are summarized and two less known relations between gravity and thermodynamics are studied. Firstly, the information cost required to operate a Maxwell's demon on a curved spacetime is estimated using the Kolmogorov-Sinai entropy. More importantly, the charge and time (C and T) reversal properties

Carl M. Bender, Philip D. Mannheim

In a recent paper Bender and Mannheim showed that the unequal-frequency fourth-order derivative Pais-Uhlenbeck oscillator model has a realization in which the energy eigenvalues are real and bounded below, the Hilbert-space inner product is positive definite, and time evolution is unitary. Central to that analysis was the recognition that the Hamiltonian $H_

Paul R. Estrada, Jeffrey N. Cuzzi

We demonstrate an approach to solving the coagulation equation that involves using a finite number of moments of the particle size distribution. This approach is particularly useful when only general properties of the distribution, and their time evolution, are needed. The numerical solution to the integro-differential Smoluchowski coagulation equation at ev

A. M. Zagoskin, E. Il'ichev, M. W. McCutcheon, Jeff Young

High-quality superconducting oscillators have been successfully used for quantum control and readout devices in conjunction with superconducting qubits. Also, it is well known that squeezed states can improve the accuracy of measurements to subquantum, or at least subthermal, levels. Here we show theoretically how to produce squeezed states of microwave radi

J. Diemand, M. Kuhlen

We show that most particle and subhalo orbits in simulated cosmological cold dark matter halos are surprisingly regular and periodic: The phase space structure of the outer halo regions shares some of the properties of the classical self-similar secondary infall model. Some of the outer branches are clearly visible in the radial velocity - radius plane at ce

Dalia Chakrabarty, Ioannis V. Sideris

{} {To quantify the amount of chaos that exists in the local phase space.} {A sample of orbits from four different models of the Solar neighbourhood phase space are analysed by a new chaos identification (and quantification) technique. While three of the used models bear the signature of the perturbation due to both the Galactic bar and the spiral pattern, t

Emmanuel I. Rashba

Anomalous Hall effect and spin Hall effect originate due to spin-orbit coupling that in the Kohn-Luttinger ${\bf k}\cdot{\bf p}$ formalism is represented by anomalous terms in the coordinate and velocity operators. Relation of these operators to the Berry curvature in the momentum space is presented for electrons in GaAs type semiconductors. For centrosymmet

Z. Kalay, P. E. Parris, V. M. Kenkre

The effect of disorder in the energetic heights and in the physical locations of fence barriers encountered by transmembrane molecules such as proteins and lipids in their motion in cell membranes is studied theoretically. The investigation takes as its starting point a recent analysis of a periodic system with constant distances between barriers and constan

V. M. Kenkre, L. Giuggioli, Z. Kalay

A theoretical calculation is presented to describe the confined motion of transmembrane molecules in cell membranes. The study is analytic, based on Master equations for the probability of the molecules moving as random walkers, and leads to explicit usable solutions including expressions for the molecular mean square displacement and effective diffusion con

Scott C. Porter, Somak Raychaudhury, Kevin A. Pimbblet, Michael J. Drinkwater

With the help of a statistical parameter derived from optical spectra, we show that the current star formation rate of a galaxy, falling into a cluster along a supercluster filament, is likely to undergo a sudden enhancement before the galaxy reaches the virial radius of the cluster. From a sample of 52 supercluster-scale filaments of galaxies joining a pair

N. Kurz, M. R. Dietrich, Gang Shu, R. Bowler

We present a measurement of the branching ratios from the 6P3/2 state of BaII into all dipoleallowed decay channels (6S1/2, 5D3/2 and 5D5/2). Measurements were performed on single 138Ba+ ions in a linear Paul trap with a frequency-doubled mode-locked Ti:Sapphire laser resonant with the 6S1/2->6P3/2 transition at 455 nm by detection of electron shelving into

A. Mourachkine

In a recent article, Alldredge et al. reported tunnelling data obtained at T = 4.2 K by STM in Bi-2212 having different doping levels, p, and a new way to fit the measured differential conductances, g(V), which are linearly proportional to the local density of states of quasiparticle excitations at the surface, N(E). The main point of the fitting procedure i

Carl M. Bender, Dorje C. Brody, Daniel W. Hook

On the basis of extensive numerical studies it is argued that there are strong analogies between the probabilistic behavior of quantum systems defined by Hermitian Hamiltonians and the deterministic behavior of classical mechanical systems extended into the complex domain. Three models are examined: the quartic double-well potential $V(x)=x^4-5x^2$, the cubi

Anthony Narkawicz

Two standard invariants used to study the fundamental group G of the complement X of a hyperplane arrangement are the Malcev completion of G and the cohomology groups of X with coefficients in rank one local systems. In this paper, we develop a tool that unifies these two approaches. This tool is the Malcev completion S_p of G relative to a homomorphism p fr

Daniel E. Welty, Thuso Simon, L. M. Hobbs

New optical spectra of Ca II and Na I toward HD 72127AB provide additional evidence for both spatial and temporal variations in the complex interstellar absorption along the two sight lines; archival UV spectra yield information on the abundances, depletions, and physical conditions in the gas toward HD 72127A. Similarities in the strengths of various tracer

N. Armesto

I present an overview of predictions for the heavy ion program at the Large Hadron Collider. It is mainly based on the material presented during the workshop 'Heavy Ion Collisions at the LHC - Last Call for Predictions', held in the frame of the CERN Theory Institute from May 14th to June 10th 2007. Predictions on both bulk properties and hard probes

Joerg Jaeckel, Javier Redondo, Andreas Ringwald

If there is a hidden photon -- i.e. a light abelian gauge boson in the hidden sector -- its kinetic mixing with the standard photon can produce a hidden cosmic microwave background (hCMB). For meV masses, resonant photon-hidden photon oscillations happen after nucleosynthesis (BBN) but before CMB decoupling, increasing the effective number of neutrinos but a

John H. Wise

Cosmic structure originated from minute density perturbations in an almost homogeneous universe. The first stars are believed to be very massive and luminous, providing the first ionizing radiation and heavy elements to the universe and forming 100 million years after the Big Bang. The impact from primordial stellar radiation is far reaching and affects subs

Felix J. Lockman, Robert A. Benjamin, A. J. Heroux, Glen I. Langston

New 21cm HI observations made with the Green Bank Telescope show that the high-velocity cloud known as Smith's Cloud has a striking cometary appearance and many indications of interaction with the Galactic ISM. The velocities of interaction give a kinematic distance of 12.4 +/-1.3 kpc, consistent with the distance derived from other methods. The Cloud is

Lex E. Renner

Let $k\subseteq K$ be a finite Galois extension of fields with Galois group $G$. Let $\mathscr{G}$ be the automorphism $k$-group scheme of $K$. We construct a canonical $k$-subgroup scheme $\underline{G}\subset\mathscr{G}$ with the property that $Spec_k(K)$ is a $k$-torsor for $\underline{G}$. $\underline{G}$ is a constant $k$-group if and only if $G$ is abe

Z. Burda, A. Krzywicki, O. C. Martin

Multi-agent models have been used in many contexts to study generic collective behavior. Similarly, complex networks have become very popular because of the diversity of growth rules giving rise to scale-free behavior. Here we study adaptive networks where the agents trade ``wealth'' when they are linked together while links can appear and disappear

Vladimir A. Sautenkov, Yuri V. Rostovtsev, Eric R. Eliel

We have experimentally studied the reflection of a weak probe beam from a dense atomic potassium vapor in the presence of a strong laser field tuned to the atomic resonance transition. We have observed an Autler-Townes doublet under hitherto unexplored conditions, namely that the Rabi frequency induced by the strong laser field is much smaller than the self-

Frithjof Karsch

We present results from a calculation of the QCD equation of state with two light (up, down) and one heavier (strange) quark mass performed on lattices with three different values of the lattice cut-off. We show that also on the finest lattice analyzed by us observables sensitive to deconfinement and chiral symmetry restoration, respectively, vary most rapid

G. Altarelli

I present a concise review of where we stand in particle physics today. First, I will discuss QCD, then the electroweak sector and finally the motivations and the avenues for new physics beyond the Standard Model.

P. Teixeira-Dias

In this paper we report on the legacy of Higgs boson searches at LEP. Specifically, the results of the statistical combination of the searches carried out by the ALEPH, DELPHI, L3 and OPAL experiments are presented. In the search for the Standard Model (SM) Higgs boson, a signal with mh<114.4 GeV/c^2 has been excluded at the 95% confidence level (CL) or high

E. L. Robinson, J. D. Romano, A. Vecchio

The analysis method currently proposed to search for isotropic stochastic radiation of primordial or astrophysical origin with the Laser Interferometer Space Antenna (LISA) relies on the combined use of two LISA channels, one of which is insensitive to gravitational waves, such as the symmetrised Sagnac. For this method to work, it is essential to know how t

K. Belczynski, R. Taam

The evolution leading to the formation of a neutron star in the very young Westerlund 1 star cluster is investigated. The turnoff mass has been estimated to be 35 Msun, indicating a cluster age ~ 3-5 Myr. The brightest X-ray source in the cluster, CXO J164710.2-455216, is a slowly spinning (10 s) single neutron star and potentially a magnetar. Since this sou

M. Kowalski, D. Rubin, G. Aldering, R. J. Agostinho

We present a new compilation of Type Ia supernovae (SNe Ia), a new dataset of low-redshift nearby-Hubble-flow SNe and new analysis procedures to work with these heterogeneous compilations. This ``Union&#39;&#39; compilation of 414 SN Ia, which reduces to 307 SNe after selection cuts, includes the recent large samples of SNe Ia from the Supernova Legacy Surve

Sergei F. Mingaleev, Andrey E. Miroshnichenko, Yuri S. Kivshar

We study the resonant transmission of light in a coupled-resonator optical waveguide interacting with two nearly identical side cavities. We reveal and describe a novel effect of the coupled-resonator-induced reflection (CRIR) characterized by a very high and easily tunable quality factor of the reflection line, for the case of the inter-site coupling betwee

Nicholas J. A. Harvey, Jelani Nelson, Krzysztof Onak

We conclude a sequence of work by giving near-optimal sketching and streaming algorithms for estimating Shannon entropy in the most general streaming model, with arbitrary insertions and deletions. This improves on prior results that obtain suboptimal space bounds in the general model, and near-optimal bounds in the insertion-only model without sketching. Ou

Ahmad El Hajj, Regis Monneau

In this paper, we study diagonalizable hyperbolic systems in one space dimension. Based on a new gradient entropy estimate, we prove the global existence of a continuous solution, for large and nondecreasing initial data. Moreover, we show in particular cases some uniqueness results. We also remark that these results cover the case of systems which are hyper

J. A. Braatz, N. E. Gugliucci

Using the Green Bank Telescope, we conducted a ``snapshot&#39;&#39; survey for water maser emission toward the nuclei of 611 galaxies and detected eight new sources. The sample consisted of nearby (v < 5000 km/s) and luminous (M_B < -19.5) galaxies, some with known nuclear activity but most not previously known to host AGNs. Our detections include both megam

Sergei F. Mingaleev, Andrey E. Miroshnichenko, Yuri S. Kivshar

We analyze the resonant transmission of light through a photonic-crystal waveguide side coupled to a Kerr nonlinear cavity, and demonstrate how to design the structure geometry for achieving bistability and all-optical switching at ultra-low powers in the slow-light regime. We show that the resonance quality factor in such structures scales inversely proport

Fumiko Kawazoe, Mitsuhiro Fukushima, Seiji Kawamura, Volker Leonhardt

Some next-generation gravitational-wave detectors, such as the American Advanced LIGO project and the Japanese LCGT project, plan to use power recycled resonant sideband extraction (RSE) interferometers for their interferometer&#39;s optical configuration. A power recycled zero-detuning (PRZD) RSE interferometer, which is the default design for LCGT, has fiv

Olivier Chesneau, Dipankar Banerjee, F. Millour, N. Nardetto

We present the first high spatial resolution monitoring of the dust forming nova V1280 Sco performed with the Very Large Telescope Interferometer (VLTI). Spectra and visibilities were obtained from the onset of the dust formation 23 days after discovery till day 145, using the instruments AMBER and MIDI. These interferometric observations are complemented by

Dmitry Borisyuk, Alexander Kobushkin

We calculate two-photon exchange amplitude for the elastic electron-proton scattering in the framework of dispersion relations. The imaginary part of the amplitude is determined by unitarity. Since in the unitarity relation intermediate states are on shell, off-shell form factors are not needed for the calculation. The real part is then evaluated using analy

Jaron Kurk, Andrea Cimatti, Gianni Zamorani, Claire Halliday

The Galaxy Mass Assembly ultra-deep Spectroscopic Survey samples a part of the CDFS to unprecedented depth. The resulting distribution of 150 z>1.4 redshifts reveals a significant peak at z=1.6, part of a larger overdensity found at this redshift. The 42 spectroscopic members of this structure, called Cl 0332-2742, form an overdensity in redshift of a factor

Marco J. Morelli, Pieter Rein ten Wolde

Brownian Dynamics algorithms are widely used for simulating soft-matter and biochemical systems. In recent times, their application has been extended to the simulation of coarse-grained models of cellular networks in simple organisms. In these models, components move by diffusion, and can react with one another upon contact. However, when reactions are incor

J. Melendez, M. Asplund, A. Alves-Brito, K. Cunha

The evolution of the Milky Way bulge and its relationship with the other Galactic populations is still poorly understood. The bulge has been suggested to be either a merger-driven classical bulge or the product of a dynamical instability of the inner disk. To probe the star formation history, the initial mass function and stellar nucleosynthesis of the bulge

Indranil Biswas, Georg Hein

It is known that a vector bundle E on a smooth projective curve Y defined over an algebraically closed field is semistable if and only if there is a vector bundle F on Y such that the cohomologies of E\otimes F vanish. We extend this criterion for semistability to vector bundles on curves defined over perfect fields. Let X be a geometrically irreducible smoo

M. T. Fernandez-Carames, P. Gonzalez, A. Valcarce

From an SU(2)$\otimes $SU(2) chiral quark potential model incorporating spontaneous chiral symmetry breaking the asymptotic $π$ and $σ$ exchange pieces of the $NN$ potential are generated. From them the $πNN$ and $σNN$ coupling constants can be extracted. The generalization to SU(3)$\otimes $SU(3) allows for a determination of $πB_{8}B_{8}$ and $% σB_{8}B_{8

Oliver Muelken, Volker Pernice, Alexander Blumen

Long-range interactions slow down the excitation trapping in quantum transport processes on a one-dimensional chain with traps at both ends. This is counter intuitive and in contrast to the corresponding classical processes with long-range interactions, which lead to faster excitation trapping. We give a pertubation theoretical explanation of this effect.

Ludovic Langevine, Mireille Ducasse

Tracers provide users with useful information about program executions. In this article, we propose a ``tracer driver&#39;&#39;. From a single tracer, it provides a powerful front-end enabling multiple dynamic analysis tools to be easily implemented, while limiting the overhead of the trace generation. The relevant execution events are specified by flexible

Branko Dragovich

We consider some nonlocal and nonpolynomial scalar field models originated from p-adic string theory. Infinite number of spacetime derivatives is determined by the operator valued Riemann zeta function through d&#39;Alembertian $\Box$ in its argument. Construction of the corresponding Lagrangians L starts with the exact Lagrangian $\mathcal{L}_p$ for effecti

S. N. Artemenko, S. V. Remizov, D. S. Shapiro

We study theoretically the electronic transport through a single impurity in a repulsive Luttinger liquid (LL), and find that above a threshold voltage related to a strength of the impurity potential the DC current $\bar I$ is accompanied by coherent oscillations with frequency $f = \bar I/e$. There is an analogy with Josephson junctions: the well-known regi

R. J. Radwanski Z. Ropka

Magnetic properties of stechiometric Cs2AgF4 have been calculated within a very strong correlation limit taking into account a low-symmetry crystal field and the intra-atomic spin-orbit coupling of the Ag2+ ion. We consistently explain the insulating ground state and the magnetic state revealing the spin gap of 2.6 meV below Tc of 14.9 K. A d-d excitation of

Luziane Carvalho, Tiago Saurin, Eduardo Bica, Charles Bonatto

The LMC and SMC are rich in binary star clusters, and some mergers are expected. It is important to characterize single clusters, binary clusters and candidates to mergers. We selected a sample of star clusters in each Cloud with this aim. Surface photometry of 25 SMC and 22 LMC star clusters was carried with the ESO Danish 1.54 m telescope. 23 clusters were

A. Sollima

I present a simplified analytical model that simulates the evolution of the binary population in a dynamically evolving globular cluster. A number of simulations have been run spanning a wide range in initial cluster and environmental conditions by taking into account the main mechanisms of formation and destruction of binary systems. Following this approach

Charles Bonatto, Eduardo Bica

We investigate the nature of a sample of star cluster candidates detected as stellar overdensities towards the Galactic anticentre. Taken from the catalogue of Froebrich, Scholz, and Raftery (FSR), the sample contains 28 star cluster candidates located within $|Δ\ell|=20^\circ$ of the anticentre. These are all the candidates in that sector classified by FSR

A. V. Butkevich

The charged-current quasi-elastic scattering of muon neutrino on the oxygen target is analyzed for neutrino energy up to 2.5 GeV using the Relativistic Distorted-Wave Impulse Approximation (RDWIA). The inclusive cross sections $d^2σ/dQ^2$, calculated within the RDWIA, are lower than the Relativistic Fermi Gas Model (RFGM) results in the range of the square o

N. I. Cade, F. Culfaz, L. Eligal, T. Ritman-Meer

We report modifications to the optical properties of fluorophores in the vicinity of noble metal nanotips. The fluorescence from small clusters of quantum dots has been imaged using an apertureless scanning near-field optical microscope. When a sharp gold tip is brought close to the sample surface, a strong distance-dependent enhancement of the quantum dot f

David Windisch

This work continues the investigation, initiated in a recent work by Benjamini and Sznitman, of percolative properties of the set of points not visited by a random walk on the discrete torus (Z/NZ)^d up to time uN^d in high dimension d. If u>0 is chosen sufficiently small it has been shown that with overwhelming probability this vacant set contains a unique

Kiumars Kaveh, Askold G. Khovanskii

Given an affine variety X and a finite dimensional vector space of regular functions L on X, we associate a convex body to (X, L) such that its volume is responsible for the number of solutions of a generic system of functions from L. This is a far reaching generalization of usual theory of Newton polytopes (which is concerned with toric varieties). As appli

J. Szavits-Nossan, K. Uzelac

The exclusion process in which particles may jump any distance l>=1 with the probability that decays as l^-(1+sigma) is studied from coarse-grained equation for density profile in the limit when the lattice spacing goes to zero. For 1<sigma<2, the usual diffusion term of this equation is replaced by the fractional one, which affects dynamical-scaling propert

Pavel Skums

We prove that Kelly-Ulam conjecture is true for p-disconnected graphs.

Avraham Gal

The major contributions of Richard H. Dalitz to hypernuclear physics, since his first paper in 1955 to his last one in 2005 covering a span of 50 years during which he founded and led the theoretical study of hypernuclei, are reviewed from a personal perspective. Topical remarks on the search for quasi-bound antikaon-nuclear states and on kaon condensation a

L. I. Plimak, S. Stenholm

We analyse nonperturbatively signal transmission patterns in Green&#39;s functions of interacting quantum fields. Quantum field theory is re-formulated in terms of the nonlinear quantum-statistical response of the field. This formulation applies equally to interacting relativistic fields and nonrelativistic models. Of crucial importance is that all causality

L. I. Plimak, S. Stenholm

It is shown that response properties of a quantum harmonic oscillator are in essence those of a classical oscillator, and that, paradoxical as it may be, these classical properties underlie all quantum dynamical properties of the system. The results are extended to non-interacting bosonic fields, both neutral and charged.

Raji Heyrovska

Two dimensional layers of graphene are currently drawing a great attention in fundamental and applied nanoscience. Graphene consists of interconnected hexagons of carbon atoms as in graphite. This article presents for the first time the structures of graphene at the atomic level and shows how it differs from that of benzene, due to the difference in the doub

Dimitar Mekerov

There is considered a connection with skew symmetric torsion on a quasi-Kähler manifold with Norden metric. Some necessary and sufficient conditions are derived for the corresponding curvature tensor to be Kählerian. In the case when this tensor is Kählerian, some relations are obtained between its scalar curvature and the scalar curvature of other curvature

Dimitar Mekerov

A Lie group as a 4-dimensional pseudo-Riemannian manifold is considered. This manifold is equipped with an almost product structure and a Killing metric in two ways. In the first case Riemannian almost product manifold with nonintegrable structure is obtained, and in the second case - a pseudo-Riemannian one. Each belongs to a 4-parametric family of manifold

Dimitar Mekerov

The $B$-connection on almost complex manifolds with Norden metric is an analogue of the first canonical connection of Lihnerovich in Hermitian geometry. In the present paper it is considered a $B$-connection in the class of the quasi-Kähler manifold with Norden metric. Some necessary and sufficient conditions are derived for the corresponding curvature tenso

M. Maamache, Y. Saadi

A quantal system in an eigenstate, of operators with a continuous nondegenerate eigenvalue spectrum, slowly transported round a circuit C by varing parameters in its Hamiltonian, will acquire a generalized geometrical phase factor. An explicit formula for a generalized geometrical phase is derived in terms of the eigenstates of the Hamiltonian. As an illustr

Amir Bashan, Ronny Bartsch, Jan W. Kantelhardt, Shlomo Havlin

We examine several recently suggested methods for the detection of long-range correlations in data series based on similar ideas as the well-established Detrended Fluctuation Analysis (DFA). In particular, we present a detailed comparison between the regular DFA and two recently suggested methods: the Centered Moving Average (CMA) Method and a Modified Detre

Fredrik Engström

Let $(M,\scott X) \models \ACA$ be such that $P_\scott X$, the collection of all unbounded sets in $\scott X$, admits a definable complete ultrafilter and let $T$ be a theory extending first order arithmetic coded in $\scott X$ such that $M$ thinks $T$ is consistent. We prove that there is an end-extension $N \models T$ of $M$ such that the subsets of $M$ co

M. Maamache, Y. Saadi

In this paper,we present a rigorous demonstration and discussion of the quantum adiabatic theorem for systems having a non degenerate continuous spectrum. A new strategy is initiated by defining a kind of gap, &#34;a virtual gap&#34;, for the continuous spectrum through the notion of eigendifferential (Weyl&#39;s packet) and using the differential projector

Saratha Sathasivam, Wan Ahmad Tajuddin Wan Abdullah

Synaptic weights for neurons in logic programming can be calculated either by using Hebbian learning or by Wan Abdullah&#39;s method. In other words, Hebbian learning for governing events corresponding to some respective program clauses is equivalent with learning using Wan Abdullah&#39;s method for the same respective program clauses. In this paper we will

A. N. Baushev

We present a phase resolved spectral analysis of the X-ray binary 4U0115+63 based upon Beppo-Sax satellite observations. Three strong absorption lines have been detected at all phases. We interpreted them as a cyclotron resonant scattering. Existence of the fourth cyclotron line has been confirmed at some phases. The cyclotron feature is found to be strongly

Saratha Sathasivam, Wan Ahmad Tajuddin Wan Abdullah

Knowledge could be gained from experts, specialists in the area of interest, or it can be gained by induction from sets of data. Automatic induction of knowledge from data sets, usually stored in large databases, is called data mining. Data mining methods are important in the management of complex systems. There are many technologies available to data mining

Daniel Campos, Vicenç Méndez, Sergei Fedotov

We explore the role of cellular life cycles for viruses and host cells in an infection process. For this purpose, we derive a generalized version of the basic model of virus dynamics (Nowak, M.A., Bangham, C.R.M., 1996. Population dynamics of immune responses to persistent viruses. Science 272, 74-79) from a mesoscopic description. In its final form the mode

S. Kimeswenger, A. A. Zijlstra, P. A. M. van Hoof, M. Hajduk

While in the past spherodicity was assumed, and still is used in modeling of most nebulae, we know now that only a small number of planetary nebulae (PNe) are really spherical or at least nearly round. Round planetary nebulae are the minority of objects. In the case of those objects that underwent a very late helium flash (called VLTP objects or ``born-again

Karin Baur

In this note we explain how to obtain cluster algebras from triangulations of (punctured) discs following the approach of S. Fomin, M. Shapiro and D. Thurston. Furthermore, we give a description of m-cluster categories via diagonals (arcs) in (punctured) polygons and of m-cluster categories via powers of translation quivers as given in joint work with R. Mar

I. R Shein, V. L. Kozhevnikov, A. L. Ivanovskii

The extensive ab initio total energy calculations using the VASP-PAW method with the generalized gradient approximation (GGA) for the exchange-correlation potential are applied to systematic investigation of structural, electronic and magnetic properties in quaternary oxybismuthides LaOMBi (where M = Sc, Ti...Ni, Cu). The energy spectrum features similar to

Jesus Fernandez-Sanchez

Given a normal surface singularity $(X, Q)$ and a birational morphism to a non- singular surface $π: X \to S$, we investigate the local geometry of the exceptional divisor $L$ of $π$. We prove that the dimension of the tangent space to $L$ at $Q$ equals the number of exceptional components meeting at $Q$. Consequences relative to the existence of such birati

A. Mucciarelli, E. Carretta, L. Origlia, F. R. Ferraro

This paper presents the chemical abundance analysis of a sample of 27 red giant stars located in 4 popolous intermediate-age globular clusters in the Large Magellanic Cloud, namely NGC 1651, 1783, 1978 and 2173. This analysis is based on high-resolution (R ~ 47000) spectra obtained with the UVES@VLT spectrograph. For each cluster we derived up to 20 abundanc

S. Kimeswenger, A. A. Zijlstra, P. A. M. van Hoof, M. Hajduk

While in the past spheroidicity was assumed, and still is used in modeling of most nebulae, we know now that only a small number of planetary nebulae (PNe) are really spherical or at least nearly round. Round planetary nebulae are the minority of objects. In case of those objects that underwent a very late helium flash (called VLTP or &#34;born-again&#34; PN

Stefan Uttenthaler, Thomas Lebzelter, Bernhard Aringer, Hans-Ulrich Käufl

We present measurements of the fluorine abundance in a Galactic Bulge Asymptotic Giant Branch (AGB) star. The measurements were performed using high resolution K-band spectra obtained with the CRIRES spectrograph, which has been recently installed at ESO&#39;s VLT, together with state-of-the-art model atmospheres and synthetic spectra. This represents the fi

Alpha Mastrano, Andrew Melatos

Recent numerical magnetohydrodynamic calculations by Braithwaite and collaborators support the `fossil field&#39; hypothesis regarding the origin of magnetic fields in compact stars and suggest that the resistive evolution of the fossil field can explain the reorganisation and decay of magnetar magnetic fields. Here, these findings are modelled analytically

Johannes Sjoestrand

In this note we compare two recent results about the distribution of eigenvalues for semi-classical pseudodifferential operators in two dimensions. For classes of analytic operators A. Melin and the author obtained a complex Bohr-Sommerfeld rule, showing that the eigenvalues are situated on a distorted lattice. On the other hand, with M. Hager we showed in a

Subhaditya Bhattacharya, AseshKrishna Datta, Biswarup Mukhopadhyaya

We study the possible signatures of non-universal scalar masses in supersymmetry at the Large Hadron Collider (LHC). This is done, following our recent study on gaugino non-universality, via a multichannel analysis, based largely on the ratios of event rates for different final states, aimed at minimizing irregularity in the pattern due to extraneous effects

L. H. Ho, W. R. Clarke, A. P. Micolich, R. Danneau

We have developed a technique utilizing a double quantum well heterostructure that allows us to study the effect of a nearby ground-plane on the metallic behavior in a GaAs two-dimensional hole system (2DHS) in a single sample and measurement cool-down, thereby maintaining a constant disorder potential. In contrast to recent measurements of the effect of gro

V. V. Slabko

The paper considers an opportunity for the creation of an artificial two-component metamaterial with a negative refractive index within the radio and optical frequency band, which possesses a spatial dispersion. It is shown that there exists a spectral region where, under certain ratio of volume fraction unit occupied with components, the metamaterial appear

Genta Ito

Permutations of particle labels are usually used to illustrate the relationship between classical and quantum statistics. We use permutations of attributes/properties of particles to express properties of waves. We express events of the well-known two-double-slit experiment (in regimes that are appropriate to quantum interference and classical interference)

Yasuhiro Nariyuki, Shuichi Matsukiyo, Tohru Hada

We discuss the parametric instabilities of large-amplitude parallel propagating Alfven waves using the 2-D PIC simulation code. First, we confirmed the results in the past study [Sakai et al, 2005] that the electrons are heated due to the modified two stream instability and that the ions are heated by the parallel propagating ion acoustic waves. However, alt

Hideyuki Izumiura, Kunio Noguchi, Wako Aoki, Satoshi Honda

Balmer and Paschen continuum emission as well as Balmer series lines of P Cygni-type profile from H_gamma through H_23 are revealed in the violet spectra of BM Gem, a carbon star associated with an oxygen-rich circumstellar shell (`silicate carbon star&#39;) observed with the high dispersion spectrograph (HDS) on the Subaru telescope. The blue-shifted absorp

Takashi Hashimoto

Let $(G,K)$ be one of the following classical irreducible Hermitian symmetric pairs of noncompact type: $(SU(p,q), S(U(p) \times U(q))),(Sp(n,R), U(n))$, or $(SO*(2n), U(n))$. Let $G_{\mathbb C}$ and $K_{\mathbb C}$ be complexifications of $G$ and $K$, respectively, and let $P$ be a maximal parabolic subgroup of $G_{\mathbb C}$ whose Levi subgroup is $K_{\ma

G. D. Fleishman, T. S. Bastian, D. E. Gary

We describe microwave and hard X-ray observations of strong quasiperiodic pulsations from the GOES X1.3 solar flare on 15 June 2003. The radio observations were made jointly by the Owens Valley Solar Array (OVSA), the Nobeyama Polarimeter (NoRP), and the Nobeyama Radioheliograph (NoRH). Hard X-ray observations were made by the Ramaty High Energy Solar Spectr

Andrew J. Walsh, Nadia Lo, Michael G. Burton, Graeme L. White

We describe observations with the Mopra radiotelescope designed to assess the feasibility of the H$_2$O maser southern Galactic plane survey (HOPS). We mapped two one-square-degree regions along the Galactic plane using the new 12 mm receiver and the UNSW Mopra spectrometer (MOPS). We covered the entire spectrum between 19.5 and 27.5 GHz using this setup wit

Juncheng Wei

We consider the following nonlinear problem in $\R^N$ $$\label{eq} - Δu +V(|y|)u=u^{p},\quad u>0 {in} \R^N, u \in H^1(\R^N) $$ where $V(r)$ is a positive function, $1<p <\frac{N+2}{N-2}$. We show that if $V(r)$ has the following expansion: There are constants $a>0$, $m>1$, $θ>0$, and $V_0>0$, such that \[ V(r)= V_0+\frac a {r^m} +O\bigl(\frac1{r^{m+θ}}\bigr)

Juncheng Wei, Shusen Yan

We consider the following prescribed scalar curvature problem on $ S^N$ (*)$$\left\{\begin{array}{l} - Δ_{S^N} u + \frac{N(N-2)}{2} u = \tilde{K} u^{\frac{N+2}{N-2}} {on} S^N, u >0 \end{array}\right. $$ where $ \tilde{K}$ is positive and rotationally symmetric. We show that if $\tilde{K}$ has a local maximum point between the poles then equation (*) has {\bf

Lotte Hollands, Joseph Marsano, Kyriakos Papadodimas, Masaki Shigemori

We geometrically engineer N=2 theories perturbed by a superpotential by adding 3-form flux with support at infinity to local Calabi-Yau geometries in type IIB. This allows us to apply the formalism of Ooguri, Ookouchi, and Park [arXiv:0704.3613] to demonstrate that, by tuning the flux at infinity, we can stabilize the dynamical complex structure moduli in a

Debdeep Jena

It is shown that current saturation in semiconducting carbon nanotubes is indistinguishable from metallic nanotubes if the carrier density is above a critical value determined by the bandgap and the LO phonon energy. This feature stems from the higher number of current-carrying states in the semiconducting tubes due to the van-Hove singularity at the band-ed

Miquel Trias, Alberto Vecchio, John Veitch

We are developing a Bayesian approach based on Markov chain Monte Carlo techniques to search for and extract information about white dwarf binary systems with the Laser Interferometer Space Antenna (LISA). Here we present results obtained by applying an initial implementation of this method to some of the data sets released in Round 1B of the Mock LISA Data