November 2007 arXiv papers — page 6

M. Sajjad Athar, S. K. Singh, M. J. Vicente Vacas

We study nuclear effects in the $F^A_3(x)$ structure function in the deep inelastic neutrino reactions on iron by using a relativistic framework to describe the nucleon spectral functions in the nucleus. The results for the ratio $R(x,Q^2)=\frac{F^A_3(x,Q^2)}{AF^N_3(x, Q^2)}$ and the Gross-Llewellyn Smith(GLS) integral $G(x,Q^2)=\int_x^1 dx F^A_3(x,Q^2)$ in

Jiang Xiongfei

Networked structure emerged from a wide range of fields such as biological systems, World Wide Web and technological infrastructure. A deeply insight into the topological complexity of these networks has been gained. Some works start to pay attention to the weighted network, like the world-wide airport network and the collaboration network, where links are n

Ghosh Saugata

We show that skew-orthogonal functions, defined with respect to Jacobi weight $w_{a,b}(x)={(1-x)}^a{(1+x)}^b$, $a$, $b>-1$, including the limiting cases of Laguerre ($w_{a}(x)=x^{a}e^{-x}$, $a > -1$) and Gaussian weight ($w(x)=e^{-x^2}$), satisfy three-term recursion relation in the quaternion space. From this, we derive generalized Christoffel-Darboux (GCD)

Yu Wang, Xiaohu Yang, H. J. Mo, Frank C. van den Bosch

We use a sample of galaxy groups selected from the SDSS DR 4 with an adaptive halo-based group finder to probe how the clustering strength of groups depends on their masses and colors. In particular, we determine the relative biases of groups of different masses, as well as that of groups with the same mass but with different colors. In agreement with previo

Janusz Adamus

It is shown that a hamiltonian $n/2$-regular bipartite graph $G$ of order $2n>8$ contains a cycle of length $2n-2$. Moreover, if such a cycle can be chosen to omit a pair of adjacent vertices, then $G$ is bipancyclic.

N. P. Robins, C. Figl, M. Jeppesen, G. R. Dennis

We present the experimental realization of a pumped atom laser. We demonstrate the pumping through measurements of the source and laser-mode atom numbers, making a rate equation study of the pumping process.

The BABAR Collaboration, B. Aubert

We report a Dalitz-plot analysis of the charmless hadronic decays of neutral B mesons to K^+/- pi^-/+ pi^0. With a sample of (231.8+/-2.6) 10^6 Upsilon(4S) to B Bbar decays collected by the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC, we measure the magnitudes and phases of the intermediate resonant and nonresonant amplitudes for B0 and

J. Ponce de Leon

We study possible static non-Schwarzschild exteriors for nonstatic spherically symmetric stars in a Randall $&$ Sundrum type II braneworld scenario. Thus, the vacuum region outside the surface of a star is assumed to be a static solution to the equation $^{(4)}R = 0$, where $^{(4)}R $ is the scalar curvature of the 4-dimensional Ricci tensor with spherical s

Joseph B. Keller, Jean-Marc Vanden-Broeck

Stirling's formula, the asymptotic expansion of $n!$ for $n$ large, or of $Γ(z)$ for $z\to \infty$, is derived directly from the recursion equation $Γ(z+1) =z Γ(s)$ and the normalization condition $Γ({1/2}) =\sqrtπ$.

Rina Anno

This paper has been withdrawn and replaced by arXiv:1309.5035. In this paper we describe some examples of so called spherical functors between triangulated categories, which generalize the notion of a spherical object. We also give sufficient conditions for a collection of spherical functors to yield a weak representation of the category of tangles, and prov

Van H. Vu, Melanie Matchett Wood, Philip Matchett Wood

We show that any finite set S in a characteristic zero integral domain can be mapped to the finite field of order p, for infinitely many primes p, preserving all algebraic incidences in S. This can be seen as a generalization of the well-known Freiman isomorphism lemma, and we give several combinatorial applications (such as sum-product estimates).

Jonathan Hales, Dmytro Karabash, Michael T. Lock

The Sarkar-Wang algorithm computes the hat version of the Heegaard Floer homology of a closed oriented three manifold. This paper analyzes the computational complexity of the Sarkar-Wang algorithm; then the algorithm is modified to obtain a better bound. Then the computational complexity of calculating HFK hat from a Heegaard diagram by means of the modified

Dilip Raghavan

We prove in ZFC that there is a MAD family of functions in omega^omega which is also maximal with respect to infinite partial functions. This solves a 20 year old question of Van Douwen. We also strengthen a result of J. Steprans stating that strongly MAD families of functions cannot be analytic. We show that analytic MAD families of functions, if they exist

A. Z. Mekjian, S. J. Lee, T. Csorgo

Data from the L3, Tasso, Opal and Delphi collaborations are analyzed in terms of a statistical model of high energy collisions. The model contains a power law critical exponent tau and Levy index alpha. These data are used to study values of tau and alpha. The very high multiplicity events in L3, Opal and Delphi are consistent with a model based on a Feynman

Leonel Robert

It is shown that the Cuntz semigroup of a space with dimension at most two, and with second cohomology of its compact subsets equal to zero, is isomorphic to the ordered semigroup of lower semicontinuous functions on the space with values in the natural numbers with the infinity adjoined. This computation is then used to obtain the Cuntz semigroup of all com

K. Kudo, T. S. Monteiro

We investigate for quantum dynamics in phase-space regions containing ``shearless tori''. We show that the properties of these peculiar classical phase-space structures -- important to the dynamics of tokamaks -- may be exploited for quantum information applications. In particular we show that shearless tori permit the non-dispersive transmission of

Janusz Adamus

We conjecture that a 2-connected graph $G$ of order $n$, in which $d(x)+d(y)\geq n-k$ for every pair of non-adjacent vertices $x$ and $y$, contains a cycle of length $n-k$ ($k<n/2$), unless $G$ is bipartite and $n-k$ is odd. This generalizes to long cycles a well-known degree sum condition for hamiltonicity of Ore. The conjecture is shown to hold for $k=1$.

S. Hussain, D. Marfatia, D. W. McKay

We show that the rate for upward showers from an isotropic cosmic neutrino flux at neutrino telescopes like IceCube is independent of the neutrino-nucleon cross section. For bins that span a relatively narrow range in energy, neither scaling the cross section, nor changing its power-law energy behavior affects the upward shower rate, which depends only on th

P. Q. Hung, Marc Sher

The existing bounds from CDF on the masses of the fourth generation quarks, t&#39; and b&#39;, are reexamined. The bound of 256 GeV on the t&#39; mass assumes that the primary decay of the t&#39; is into q+W, which is not the case for a substantial region of parameter space. The bound of 268 GeV on the b&#39; mass assumes that the branching ratio for b&#39;

Bruce K. Driver, Maria Gordina

We show that the logarithmic derivatives of the convolution heat kernels on a uni-modular Lie group are exponentially integrable. This result is then used to prove an &#34;integrated&#34; Harnack inequality for these heat kernels. It is shown that this integrated Harnack inequality is equivalent to a version of Wang&#39;s Harnack inequality. (A key feature o

Murat Yuksel, Tansel Karabacak, Hasan Guclu

Thin film coatings have been essential in development of several micro and nano-scale devices. To realize thin film coatings various deposition techniques are employed, each yielding surface morphologies with different characteristics of interest. Therefore, understanding and control of the surface growth is of great interest. In this paper, we devise a nove

Erin J. D. Jolley, Zdenka Kuncic

We revisit theoretical and observational constraints on geometrically-thin disk accretion in Sagittarius A* (Sgr A*). We show that the combined effects of mass outflows and electron energization in the hot part of the accretion flow can deflate the inflowing gas from a geometrically-thick structure. This allows the gas to cool and even thermalize on an inflo

C. Dong, W. Zhang

The rational and C_2-cofinite simple vertex operator algebras whose effective central charges and the central charges c are equal and less than 1 are classified. Such a vertex operator algebra is zero if c<0 and C if c=0. If c>0, it is an extension of discrete Virasoro vertex operator algebra L(c_{p,q},0) by its irreducible modules. It is also proved that fo

W. Zhang, C. Dong

In this paper the W-algebra W(2,2) and its representation theory are studied. It is proved that a simple vertex operator algebra generated by two weight 2 vectors is either a vertex operator algebra associated to a highest irreducible W(2,2)-module or a tensor product of two irreducible Virasoro vertex operator algebras. Furthermore, any rational, C_2-cofini

Carsten Gundlach, Jose M. Martin-Garcia

As first discovered by Choptuik, the black hole threshold in the space of initial data for general relativity shows both surprising structure and surprising simplicity. Universality, power-law scaling of the black hole mass, and scale echoing have given rise to the term &#34;critical phenomena&#34;. They are explained by the existence of exact solutions whic

Benjamin Doyon, Adam Gamsa

This work concerns the dynamical two-point spin correlation functions of the transverse Ising quantum chain at finite (non-zero) temperature, in the universal region near the quantum critical point. They are correlation functions of twist fields in the massive Majorana fermion quantum field theory. At finite temperature, these are known to satisfy a set of i

Klaus M. Pontoppidan, A. C. A. Boogert, Helen J. Fraser, Ewine F. van Dishoeck

This paper presents Spitzer-IRS spectroscopy of the CO2 15.2 micron bending mode toward a sample of 50 embedded low-mass stars in nearby star-forming clouds, taken mostly from the ``Cores to Disks (c2d)&#39;&#39; Legacy program. The average abundance of solid CO2 relative to water in low-mass protostellar envelopes is 0.32 +/- 0.02, significantly higher than

A. C. Mclaughlin, L. Begg, C. Harrow, S. A. J. Kimber

High critical-temperature superconductivity and large (colossal) magnetoresistances are two important electronic conducting phenomena found in transition metal oxides. High-Tc materials have applications such as superconducting magnets for MRI and NMR, and magnetoresistive materials may find use in magnetic sensors and spintronic devices. Here we report chem

A. C. Mclaughlin, F. Sher, S. A. J. Kimber, J. P. Attfield

RuSr2(Nd,Y,Ce)2Cu2O10-d ruthenocuprates have been studied by neutron diffraction, magnetotransport and magnetisation measurements and the electronic phase diagram is reported. Separate Ru and Cu spin ordering transitions are observed, with spontaneous Cu antiferromagnetic order for low hole doping levels p, and a distinct, induced-antiferromagnetic Cu spin p

Y. S. Kozhedub, O. V. Andreev, V. M. Shabaev, I. I. Tupitsyn

Nuclear deformation effects on the binding energies in heavy ions are investigated. Approximate formulas for the nuclear-size correction and the isotope shift for deformed nuclei are derived. Combined with direct numerical evaluations, these formulas are employed to reanalyse experimental data on the nuclear-charge-distribution parameters in $^{238}\textrm{U

Yancy L. Shirley, Jingwen Wu, R. Shane Bussmann, Al Wootten

We review the evidence for a constant star formation rate per unit mass in dense molecular gas in the Milky Way and the extragalactic correlations of L_IR with L&#39; from observations of dense molecular gas. We discuss the connection between the constant SFR/M interpretation in dense gas and the global Schmidt-Kennicutt star formation law.

James R. Mullaney, Martin J. Ward

Based on a new spectroscopic sample observed using the WHT, we examine the kinematic properties of the various emission line regions in narrow line Seyfert 1 galaxies (NLS1s) by modelling their profiles using multiple component fits. We interpret these results by comparison with velocity components observed for different lines species covered in the same spe

Mladen Georgiev

A mechanism is proposed to explain the formation of a small-polaron superlattice above the Curie temperature in manganites. The order-disorder transition initiated by the external field at a lattice is known responsible for the colossal resistance effect. We attribute the lattice formation to the occurrence of strong Van der Waals pairing of vibronic small p

Lian-Ao Wu, Dvira Segal

We derive the macroscopic Fourier&#39;s Law of heat conduction from the exact gain-loss time convolutionless quantum master equation under three assumptions for the interaction kernel. To second order in the interaction, we show that the first two assumptions are natural results of the long time limit. The third assumption can be satisfied by a family of int

Oleg Y. Gnedin, Jose L. Prieto

We probe the evolution of globular clusters that could form in giant molecular clouds within high-redshift galaxies. Numerical simulations demonstrate that the large and dense enough gas clouds assemble naturally in current hierarchical models of galaxy formation. These clouds are enriched with heavy elements from earlier stars and could produce star cluster

Derrick Hart, Alex Iosevich

An analog of the Falconer distance problem in vector spaces over finite fields asks for the threshold $α>0$ such that $|Δ(E)| \gtrsim q$ whenever $|E| \gtrsim q^α$, where $E \subset {\Bbb F}_q^d$, the $d$-dimensional vector space over a finite field with $q$ elements (not necessarily prime). Here $Δ(E)=\{{(x_1-y_1)}^2+...+{(x_d-y_d)}^2: x,y \in E\}$. The sec

R. Liao, F. Popescu, K. Quader

We explore p-wave pairing in a single-channel two-component Fermi system with unequal population near Feshbach resonance. Our analytical and numerical study reveal a rich superfluid (SF) ground state structure as a function of imbalance. In addition to the state $Δ_{\pm 1} \propto Y_{1\pm 1}$, a multitude of ``mixed&#39;&#39; SF states formed of linear combi

Xiaodong Wang

Let $(M^{n},g)$ be a compact Riemannian manifold with $Ric\geq-(n-1) $. It is well known that the bottom of spectrum $λ_{0}$ of its unverversal covering satisfies $λ_{0}\leq(n-1) ^{2}/4 $. We prove that equality holds iff $M$ is hyperbolic. This follows from a sharp estimate for the Kaimanovich entropy.

Sarbani Basu, H. M. Antia

Helioseismology has allowed us to study the structure of the Sun in unprecedented detail. One of the triumphs of the theory of stellar evolution was that helioseismic studies had shown that the structure of solar models is very similar to that of the Sun. However, this agreement has been spoiled by recent revisions of the solar heavy-element abundances. Heav

N. J. C. Ingle, I. S. Elfimov

From first principles calculations we investigate the electronic structure and the magnetic properties of EuO under hydrostatic and epitaxial forces. There is a complex interdependence of the O 2p and Eu 4f and 5d bands on the magnetism in EuO, and decreasing lattice parameters is an ideal method to increase the Curie temperature, T_c. Compared to hydrostati

E. G. Altmann, T. Friedrich, A. E. Motter, H. Kantz

The dynamics of chaotic billiards is significantly influenced by coexisting regions of regular motion. Here we investigate the prevalence of a different fundamental structure, which is formed by marginally unstable periodic orbits and stands apart from the regular regions. We show that these structures both {\it exist} and {\it strongly influence} the dynami

G. Bourda

The high accuracy now reached in the VLBI Earth Orientation Parameters (EOP) determination requires looking further at the various geophysical contributions to variations in EOP. The determination of the Earth gravity field from space geodetic techniques now allows us to obtain the temporal variations of the low degree coefficients of the geopotential, combi

G. Bourda

The &#34;Descartes-Nutation&#34; Project is devoted to the &#34;understanding of the next decimal of precession-nutation, from the theoretical point of view as well as from the observational point of view&#34;. In this framework, we made a proposal in order to contribute to the study of (i) the dynamical flattening of the Earth, (ii) the coupling effects of

G. Bourda

The masses distribution inside the Earth governs the behaviour of the rotation axis in the Earth (polar motion), as well as the Earth rotation rate (or equivalently, length of day). This masses distribution can be measured from space owing to artificial satellites, the orbitography of which provides the Earth gravity field determination. Then, the temporal v

Guillaume Galliéro, S. Volz

In this work, a new algorithm is proposed to compute single particle (infinite dilution) thermodiffusion using Non-Equilibrium Molecular Dynamics simulations through the estimation of the thermophoretic force that applies on a solute particle. This scheme is shown to provide consistent results for simple Lennard-Jones fluids and for model nanofluids (spheric

G. Bourda, N. Capitaine

Due to the accuracy now reached by space geodetic techniques, and also considering some modelisations, the temporal variations of some Earth Gravity Field coefficients can be determined. They are due to Earth oceanic and solid tides, as well as geophysical reservoirs masses displacements. They can be related to the variations in the Earth&#39;s orientation p

H1 Collaboration

The production of isolated photons in deep-inelastic scattering $ep\to e γX$ is measured with the H1 detector at HERA. The measurement is performed in the kinematic range of negative four-momentum transfer squared $4<Q^2<150 $~GeV$^2$ and a mass of the hadronic system $W_X>50$ GeV. The analysis is based on a total integrated luminosity of 227~pb$^{-1}$. The

G. Bourda

Several satellite missions, devoted to the study of the Earth gravity field, have been launched (like CHAMP, recently). This year, GRACE (Gravity Recovery and Climate Experiment) will allow us to obtain a more precise geoid. But the most important is that they will supply the temporal variations of the geopotential coefficients (called Stokes coefficients).

Michel Destrade

Efforts at modelling the propagation of seismic waves in half-spaces with continuously varying properties have been mostly focused on shear-horizontal waves. Here a sagittaly polarized (Rayleigh type) wave travels along a symmetry axis (and is attenuated along another) of an orthotropic material with stiffnesses and mass density varying in the same exponenti

G. Bourda, N. Capitaine

Precession and nutation of the Earth depend on the Earth&#39;s dynamical flattening, H, which is closely related to the second degree zonal coefficient, J2 of the geopotential. A small secular decrease as well as seasonal variations of this coefficient have been detected by precise measurements of artificial satellites (Nerem et al. 1993; Cazenave et al. 199

Anthony Randriamampianina, Pierre Maubert, Wolf-Gerrit Fruh, Peter L. Read

The onset of small-scale fluctuations around a steady convection pattern in a rotating baroclinic annulus filled with air is investigated using Direct Numerical Simulation. In previous laboratory experiments of baroclinic waves, such fluctuations have been associated with a flow regime termed Structural Vacillation which is regarded as the first step in the

Pierre Charbit, Michel Habib, Vincent Limouzy, Fabien De Montgolfier

Let ${\cal V}$ be a finite set of $n$ elements and ${\cal F}=\{X_1,X_2, >..., X_m\}$ a family of $m$ subsets of ${\cal V}.$ Two sets $X_i$ and $X_j$ of ${\cal F}$ overlap if $X_i \cap X_j \neq \emptyset,$ $X_j \setminus X_i \neq \emptyset,$ and $X_i \setminus X_j \neq \emptyset.$ Two sets $X,Y\in {\cal F}$ are in the same overlap class if there is a series $

D. C. Gabuzda, V. M. Vitrishchak, M. Mahmud, S. P. O&#39;Sullivan

Homan & Lister (2006) have recently published circular-polarization (CP) detections for 34 objects in the MOJAVE sample - a set of bright, compact AGN being monitored by the Very Long Baseline Array at 15 GHz. We report the detection of 15-GHz parsec-scale CP in two more AGN (3C345 and 2231+114), and confirm the MOJAVE detection of CP in 1633+382. It is gene

A. V. Milovanov, K. Rypdal, J. J. Rasmussen

The concept of percolation is combined with a self-consistent treatment of the interaction between the dynamics on a lattice and the external drive. Such a treatment can provide a mechanism by which the system evolves to criticality without fine tuning, thus offering a route to self-organized criticality (SOC) which in many cases is more natural than the wea

V. M. Aulchenko, P. A. Papushev, M. R. Sharafutdinov, L. I. Shekhtman

A one-coordinate gaseous detector of soft X-ray photons for wide-angle X-ray scattering (WAXS) studies is being developed. The detector operates in counting mode and is based on multi-stage Gas Electron Multiplier(GEM). Full size detector is assembled and has 67 degrees aperture with 350mm distance to the source, readout multi-strip structure with 2048 strip

Savely G. Karshenboim

At present a number of current or proposed experiments are directed towards a search for a `new physics&#39; by detecting variations of fundamental physical constants or violations of certain basic symmetries. Various problems related to the phenomenology of such experiments are considered here.

Daniel P. Snowman

This note details a minimal effort program, Cash Participation, that quantifies class participation while increasing class energy, decreasing student apathy and removing student embraced anonymity.

Savely G. Karshenboim

The CODATA recommended values of the fundamental constants are widely applied in particle, nuclear and atomic physics. They are a result of a complicated evaluation (adjustment) of numerous correlated data of different nature. Their application is often rather mechanical and as a result is not free of various confusions which are discussed in this note.

Marcelo M. Miller Bertolami, Leandro G. Althaus

We present numerical simulations of the very late thermal pulse (VLTP) scenario for a wide range of remnant masses. We show that, by taking into account the different possible remnant masses, the fast outburst evolution of V4334 Sgr (a.k.a. Sakurai&#39;s Object) and V605 Aql can be reproduced within standard 1D stellar evolution models. A dichotomy in the bo

O. K. Krienke, Paul W. Hodge

This paper reports on a survey of star clusters in M31 based on archival images from the Hubble Space Telescope. Paper I (Krienke and Hodge 2007) reported results from images obtained with the Wide Field/Planetary Camera 2 (WFPC2) and this paper reports results from the Advanced Camera for Surveys (ACS). The ACS survey has yielded a total of 339 star cluster

Yuval Shavitt, Eran Shir, Udi Weinsberg

The discovery of Autonomous Systems (ASes) interconnections and the inference of their commercial Type-of-Relationships (ToR) has been extensively studied during the last few years. The main motivation is to accurately calculate AS-level paths and to provide better topological view of the Internet. An inherent problem in current algorithms is their extensive

Aki Roberge, Alycia J. Weinberger

We conducted a survey for infrared excess emission from 16 nearby main sequence shell stars using the Multiband Imaging Photometer for Spitzer (MIPS) on the Spitzer Space Telescope. Shell stars are early-type stars with narrow absorption lines in their spectra that appear to arise from circumstellar (CS) gas. Four of the 16 stars in our survey showed excess

Christian Heiliger, M. D. Stiles

We calculate the spin-transfer torque in Fe/MgO/Fe tunnel junctions and compare the results to those for all-metallic junctions. We show that the spin-transfer torque is interfacial in the ferromagnetic layer to a greater degree than in all-metallic junctions. This result originates in the half metallic behavior of Fe for the $Δ_1$ states at the Brillouin zo

Victor Kurasov

The full theoretical analysis of the kinetics of multicomponent nucleation is presented. The relief of the free energy with surface excesses was analyzed, the valleys and ridges were described, their mutual interaction was studied. The new possibility to change the valley of nucleation is shown. The possibility to have one common valley instead of several ne

Wenyi Zhang, Urbashi Mitra

This paper investigates point-to-point information transmission over a wideband slow-fading channel, modeled as an (asymptotically) large number of independent identically distributed parallel channels, with the random channel fading realizations remaining constant over the entire coding block. On the one hand, in the wideband limit the minimum achievable en

Diana López Nacir, Francisco D. Mazzitelli

We consider free and self-interacting quantum scalar fields satisfying modified dispersion relations in the framework of Einstein-Aether theory. Using adiabatic regularization, we study the renormalization of the equation for the mean value of the field in the self-interacting case, and the renormalization of the semiclassical Einstein-Aether equations for f

Markus A. Schmidt, Luis N. Prill Sempere, Hemant K. Tyagi, Chris G. Poulton

We report the fabrication of triangular lattices of parallel gold and silver nanowires of high optical quality, with diameters down to 500 nm and length-to-diameter ratios as high as 100,000. The nanowires are supported by a silica glass matrix and are disposed around a central solid glass core, i.e., a missing nanowire. These cm-long structures make it poss

O. Zarchin, M. Zaffalon, M. Heiblum, D. Mahalu

We report on noise measurements in a quantum dot in the presence of Kondo correlations. Close to the unitary limit, with the conductance reaching 1.8e2/h, we observed an average backscattered charge of e*~5e/3, while weakly biasing the quantum dot. This result held to bias voltages up to half the Kondo temperature. Away from the unitary limit, the charge was

D. C. Lis, D. Bockelee-Morvan, J. Boissier, J. Crovisier

We present a sensitive 3-sigma upper limit of 1.1% for the HNC/HCN abundance ratio in comet 73P/Schwassmann-Wachmann (Fragment B), obtained on May 10-11, 2006 using Caltech Submillimeter Observatory (CSO). This limit is a factor of ~7 lower than the values measured previously in moderately active comets at 1 AU from the Sun. Comet 73P/Schwassmann-Wachmann wa

S. Taubenberger, S. Hachinger, G. Pignata, P. A. Mazzali

Optical observations of the Type Ia supernova (SN Ia) 2005bl in NGC 4070, obtained from -6 to +66 d with respect to the B-band maximum, are presented. The photometric evolution is characterised by rapidly-declining light curves and red colours at peak and soon thereafter. With M_B,max = -17.24 the SN is an underluminous SN Ia, similar to the peculiar SNe 199

S. Bellucci, S. Ferrara, R. Kallosh, A. Marrani

These lectures provide a pedagogical, introductory review of the so-called Attractor Mechanism (AM) at work in two different 4-dimensional frameworks: extremal black holes in N=2 supergravity and N=1 flux compactifications. In the first case, AM determines the stabilization of scalars at the black hole event horizon purely in terms of the electric and magnet

M. Chaichian, M. R. Setare, A. Tureanu, G. Zet

Deformed Reissner-Nordström, as well as Reissner-Nordström de Sitter, solutions are obtained in a noncommutative gauge theory of gravitation. The gauge potentials (tetrad fields) and the components of deformed metric are calculated to second order in the noncommutativity parameter. The solutions reduce to the deformed Schwarzschild ones when the electric cha

Sylvain Brochard

In this article we study the Picard functor and the Picard stack of an algebraic stack. We give a new and direct proof of the representability of the Picard stack. We prove that it is quasi-separated, and that the connected component of the identity is proper when the fibers of the stack are geometrically normal. We study some examples of Picard functors of

Yogiro Hama, Rone Peterson G. Andrade, Frédérique Grassi, Wei-Liang Qian

By using the NexSPheRIO code, we study the elliptic-flow fluctuations in Au+Au collisions at 200A GeV. It is shown that, by fixing the parameters of the model to correctly reproduce the charged pseudo-rapidity and the transverse-momentum distributions, reasonable agreement of <v_2> with data is obtained, both as function of pseudo-rapidity as well as of tran

I. Iliev, J. Budaj

It is argued that apart from the well known dependence of the Am phenomenon on the mass, age (effective temperature, gravity) and rotation there is also a complex dependence on the orbital parameters in binary systems. This is why the generally accepted scenario in which the Am star rotation plays a unique role needs to be revisited, the strong correlations

Torsten Boeker

The globular cluster system of a typical spheroidal galaxy makes up about 0.25% of the total galaxy mass (McLaughlin 1999). This is roughly the same mass fraction as contained in the nuclear star clus- ter (or stellar nucleus) present in most nearby low-mass galaxies. Motivated by this &#34;coincidence&#34;, this Letter discusses a scenario in which globular

Shahar Hod

The canonical Bartnik-McKinnon solitons are regular solutions of the coupled Einstein-Yang-Mills system in which gravity may balance the repulsive nature of the Yang-Mills field. We examine the role played by gravity in balancing the system and determine its strength. In particular, we obtain an analytic lower bound on the fundamental mass-to-radius ratio, m

Jack Kuipers, Martin Sieber

The Wigner time delay of a classically chaotic quantum system can be expressed semiclassically either in terms of pairs of scattering trajectories that enter and leave the system or in terms of the periodic orbits trapped inside the system. We show how these two pictures are related on the semiclassical level. We start from the semiclassical formula with the

D. Lagarde, A. Balocchi, H. Carrere, P. Renucci

The optical orientation of the exciton spin in an ensemble of self-organized cubic GaN/AlN quantum dots is studied by time-resolved photoluminescence. Under a polarized quasi-resonant excitation, the luminescence linear polarization exhibits no temporal decay, even at room temperature. This demonstrates the robustness of the exciton spin polarization in thes

A. Cernoch, J. Soubusta, L. Bartuskova, M. Dusek

We present a linear-optical implementation of a class of two-qubit partial SWAP gates for polarization states of photons. Different gate operations, including the SWAP and entangling square root of SWAP, can be obtained by changing a classical control parameter -- namely the path difference in the interferometer. Reconstruction of output states, full process

V. Scardaci, S. Piscanec, Michele Lazzeri, R. Krupke

We measure the temperature dependence of the Raman spectra of metallic and semiconducting nanotubes. We show that the different trend in metallic tubes is due to phonon re-normalization induced by the variation in electronic temperature, which is modeled including non-adiabatic contributions to account for the dynamic, time dependent nature

S. Gomès, Po Chapuis, F. Nepveu, N. Trannoy

Surface temperature measurements were performed with a Scanning Thermal Microscope mounted with a thermoresistive wire probe of micrometrSurface temperature measurements were performed with a Scanning Thermal Microscope mounted with a thermoresistive wire probe of micrometric size. A CMOS device was designed with arrays of resistive lines 0.35$μ$m in width.

Markku Markkanen, Juha Vierinen

This work introduces a method for constructing polyphase alternating codes in which the length of a code transmission cycle can be $p^m$ or $p-1$, where $p$ is a prime number and $m$ is a positive integer. The relevant properties leading to the construction alternating codes and the algorithm for generating alternating codes is described. Examples of all pra

A. I. Akimenko, V. A. Gudimenko

When the $d_{x^2-y^2}$-wave pairing is suppressed by Zn-doping in $YBa_2Cu_3O_{7-δ}$ some of the Andreev reflection spectra were found to be similar to the s-wave spectra of conventional superconductors. The energy gap is rather reproducible (2.3-3.0meV). It is suppressed by low magnetic field ($H_C^{PC}=120-270mT$) in great contrast to the d-wave spectra ($

Thomas Martinelli, Jean-Luc Bosson, Luc Bressollette, Franck Pelissier

OBJECTIVE: The TER system is a robot-based tele-echography system allowing remote ultrasound examination. The specialist moves a mock-up of the ultrasound probe at the master site, and the robot reproduces the movements of the real probe, which sends back ultrasound images and force feedback. This tool could be used to perform ultrasound examinations in smal

Harald W. Griesshammer

Classifying the strengthes of three-body forces 3BFs with the condition that observables must be cut-off independent, i.e. renormalised at each order, leads to surprising results with relevance for example for thermal neutron capture on the deuteron. Details and a better bibliography in Ref. [1].

P. M. Bellan

Conservation of canonical angular momentum shows that charged particles are typically constrained to stay within a poloidal Larmor radius of a poloidal magnetic flux surface. However, more detailed consideration shows that particles with a critical charge to mass ratio can have zero canonical angular momentum and so be both immune from centrifugal force and

Albert Fathi, Alessio Figalli

In this work, we show how to obtain for non-compact manifolds the results that have already been done for Monge Transport Problem for costs coming from Tonelli Lagrangians on compact manifolds. In particular, the already known results for a cost of the type $d^r,r>1$, where $d$ is the Riemannian distance of a complete Riemannian manifold, hold without any cu

M. Ave

In the fluorescence detection of ultra high energy (> 10**18 eV) cosmic rays, the number of emitted fluorescence photons is assumed to be proportional to the energy deposited in air by shower particles. We have performed measurements of the fluorescence yield in atmospheric gases excited by electrons over energies ranging from keV to hundreds of MeV in sever

Philippe Merloz, Jocelyne Troccaz, Hervé Vouaillat, Christian Vasile

The variability in width, height, and spatial orientation of a spinal pedicle makes pedicle screw insertion a delicate operation. The aim of the current paper is to describe a computer-assisted surgical navigation system based on fluoroscopic X-ray image calibration and three-dimensional optical localizers in order to reduce radiation exposure while increasi

Mario G. Silveirinha, Carlos A. Fernandes, Jorge R. Costa

In this work, we demonstrate that the interaction of electromagnetic waves with a microstructured material formed by metallic wires connected to a metallic surface can be described using homogenization methods provided an additional boundary condition is considered. The additional boundary condition is derived by taking into account the specific microstructu

M. J. Morelli, R. J. Allen, S. Tanase-Nicola, P. R. ten Wolde

In many stochastic simulations of biochemical reaction networks, it is desirable to ``coarse-grain&#39;&#39; the reaction set, removing fast reactions while retaining the correct system dynamics. Various coarse-graining methods have been proposed, but it remains unclear which methods are reliable and which reactions can safely be eliminated. We address these

Z. Mikulasek

In the last few decades both the volume of high-quality observing data on variable stars and common access to them have boomed; however the standard used methods of data processing and interpretation have lagged behind this progress. The most popular method of data treatment remains for many decades Linear Regression (LR) based on the principles of Least Squ

Rikard Olofsson

This paper concerns the behavior of eigenfunctions of quantized cat maps and in particular their supremum norm. We observe that for composite integer values of N, the inverse of Planck&#39;s constant, some of the desymmetrized eigenfunctions have very small support and hence very large supremum norm. We also prove an entropy estimate and show that our functi

Oded Kafri

It is a common belief that in any environment where life is possible, life will be generated. Here it is suggested that the cause for a spontaneous generation of complex systems is probability driven processes. Based on equilibrium thermodynamics, it is argued that in low occupation number statistical systems, the second law of thermodynamics yields an incre

Seda Aksoy, Thorsten Krenke, Mehmet Acet, Eberhard F. Wassermann

Ni$_{50}$Mn$_{34}$In$_{16}$ undergoes a martensitic transformation around 250 K and exhibits a field induced reverse martensitic transformation and substantial magnetocaloric effects. We substitute small amounts Ga for In, which are isoelectronic, to carry these technically important properties to close to room temperature by shifting the martensitic transfo

G. Ya. Korenman, S. N. Yudin

Stark transitions and induced annihilation of antiproton in the collisions of antiprotonic helium ions (\bar{p}He^{+2})_{nl} with He atoms at very low energy (~ 10 K) are considered in the framework of quantum coupled-channels method taking into account all the states with different l at given n~30, including the annihilating ns and np-states. Elastic scatte

Yasuhiro Imafuku, Namiko Mitarai, Katsuhisa Tawada, Hiizu Nakanishi

It has been found in in vitro experiments that cytoskeletal filaments driven by molecular motors show finite diffusion in sliding motion even in the long filament limit [Y. Imafuku et al., Biophys. J. 70 (1996) 878-886; N. Noda et al., Biophys. 1 (2005) 45-53]. This anomalous fluctuation can be an evidence for cooperativity among the motors in action because

N. Rowell, M. Kilic, N. C. Hambly

We present photographic B, R and I photometry, and optical and near-infrared spectroscopy, of a new ultracool white dwarf (UCWD) discovered in the SuperCOSMOS Sky Survey. The spectrum of SSSJ1556-0806 shows strong flux suppression due to the presence of collisionally induced absorption by molecular hydrogen (H2CIA), a feature characteristic of the cool, high

I. Boztosun, M. Karakoc

We derive a formula that simplifies the original asymptotic iteration method formulation to find the energy eigenvalues for the analytically solvable cases. We then show that there is a connection between the asymptotic iteration and the Nikiforov--Uvarov methods, which both solve the second order linear ordinary differential equations analytically.