March 2006 arXiv papers — page 46

Nguyen Ba An

By exactly solving the underlying Schödinger equation we show that one and the same resonant cavity can be used as a catalyst to maximally entangle atoms of two nonidentical groups. The generation scheme is realistic and advantageous in the sense that it is deterministic, efficient, scalable and immune from decoherence effects.

Giuseppe Bimonte

In Phys. Rev. {\bf E 70}, 047102 (2004), J.R. Torgerson and S.K. Lamoreaux investigated for the first time the real-frequency spectrum of finite temperature correction to the Casimir force, for metallic plates of finite conductivity. The very interesting result of this study is that the correction from the TE mode is dominated by low frequencies, for which t

Hoshang Heydari

We construct an entanglement measure that coincides with the generalized concurrence for a general pure bipartite state based on wedge product. Moreover, we construct an entanglement measure for pure multi-qubit states, which are entanglement monotone. Furthermore, we generalize our result on a general pure multipartite state.

Cuneyt Berkdemir, Ayse Berkdemir, Ramazan Sever

We investigate complex PT and non-PT-symmetric forms of the generalized Woods- Saxon potential. We also look for exact solutions of the Schrodinger equation for the PT and/or non-PT-symmetric potentials of the kind mentioned above. Nikiforov-Uvarov method is used to obtain their energy eigenvalues and associated eigenfunctions.

Emily Stone, John Goldes, Martha Garlick

PCR (Polymerase Chain Reaction), a method which replicates a selected sequence of DNA, has revolutionized the study of genomic material, but mathematical study of the process has been limited to simple deterministic models or descriptions relying on stochastic processes. In this paper we develop a suite of deterministic models for the reactions of quantitati

Luca Sguanci, Franco Bagnoli, Pietro Lio

During the HIV infection several quasispecies of the virus arise, which are able to use different coreceptors, in particular the CCR5 and CXCR4 coreceptors (R5 and X4 phenotypes, respectively). The switch in coreceptor usage has been correlated with a faster progression of the disease to the AIDS phase. As several pharmaceutical companies are starting large

Debojyoti Dutta, Ting Chen

Mining large-scale high-throughput tandem mass spectrometry data sets is a very important problem in mass spectrometry based protein identification. One of the fundamental problems in large scale mining of spectra is to design appropriate metrics and algorithms to avoid all-pair-wise comparisons of spectra. In this paper, we present a general framework based

Ivaylo I. Balchev, Nikolai I. Minkovski, Ivan K. Kostadinov, Nikola V. Sabotinov

The application of the copper bromide (CuBr) laser as an attractive tool in the micro-machining of different materials has been demonstrated. High-quality drilling by trepanning and precision cutting was established on several materials with a negligible heat-affected zone (HAZ). That good performance was a result of the combination of high power visible rad

Jie Ren, Wen-Xu Wang, Gang Yan, Bing-Hong Wang

The evolutionary Prisoner's Dilemma Game (PDG) and the Snowdrift Game (SG) with preferential learning mechanism are studied in the Barabási-Albert network. Simulation results demonstrate that the preferential learning of individuals remarkably promotes the cooperative behavior for both two games over a wide range of payoffs. To understand the effect of p

Jacqueline van Veldhoven, Hendrick L. Bethlem, Melanie Schnell, Gerard Meijer

A four electrode electrostatic trap geometry is demonstrated that can be used to combine a dipole, quadrupole and hexapole field. A cold packet of 15ND3 molecules is confined in both a purely quadrupolar and hexapolar trapping field and additionally, a dipole field is added to a hexapole field to create either a double-well or a donut-shaped trapping field.

Michael Schnegg

Research in network science has shown that many naturally occurring and technologically constructed networks are scale free, that means a power law degree distribution emerges from a growth model in which each new node attaches to the existing network with a probability proportional to its number of links (=degree). Little is known about whether the same pri

D. Dimitropoulos, D. R. Solli, R. Claps, B. Jalali

The noise figure and photon probability distribution are calculated for coherent anti-Stokes Raman scattering (CARS) where an anti-Stokes signal is converted to Stokes. We find that the minimum noise figure is ~ 3dB.

Li-Gang Wang, Shi-Yao Zhu

The dynamics of two-dimensional electromagnetic (EM) pulses through one-dimensional photonic crystals (1DPC) has been theoretically studied. Employing the time expectation integral over the Poynting vector as the arrival time [Phys. Rev. Lett. 84, 2370, (2000)], we show that the superluminal tunneling process of EM pulses is the propagation of the net forwar

Jean Kergomard, Vincent Debut, Denis Matignon

Studying the problem of wave propagation in media with resistive boundaries can be made by searching for "resonance modes" or free oscillations regimes. In the present article, a simple case is investigated, which allows one to enlighten the respective interest of different, classical methods, some of them being rather delicate. This case is the 1D p

O. S. Shevchenko, Yu. M. Ranyuk, A. M. Dovbnya, V. I. Noga

The yield of the isomeric state 117mSn (Eiso = 314.58 keV) has been measured in (gamma, gamma') reaction by activation method with the bremsstrahlung end-point energy from 2.1 to 3.0 MeV. Only one intermediate state (IS) responsible for the isomer feeding has been found. The excitation energy of the IS (2.25 +/- 0.05) MeV and photoproduction integral cro

Hironori Inoue, Daisuke Takahashi, Junta Matsukidaira

We propose discrete mappings of second order that have a discrete analogue of Lyapunov function. The mappings are extensions of the integrable Quispel-Roberts-Thompson (QRT) mapping, and a discrete Lyapunov function of the mappings is identical to an explicit conserved quantity of the QRT mapping. Moreover we can obtain a differential and an ultradiscrete li

Xiaodong Luo, Tomomichi Nakamura, Michael Small

The surrogate data method is widely applied as a data dependent technique to test observed time series against a barrage of hypotheses. However, often the hypotheses one is able to address are not those of greatest interest, particularly for system known to be nonlinear. In the review we focus on techniques which overcome this shortcoming. We summarize a num

Olof Goernerup, James P. Crutchfield

Current analyses of genomes from numerous species show that the diversity of organism's functional and behavioral characters is not proportional to the number of genes that encode the organism. We investigate the hypothesis that the diversity of organismal character is due to hierarchical organization. We do this with the recently introduced model of the

Narciso Roman-Roy

Some subjects related to the geometric theory of singular dynamical systems are reviewed in this paper. In particular, the following two matters are considered: the theory of canonical transformations for presymplectic Hamiltonian systems, and the Lagrangian and Hamiltonian constraint algorithms and the time-evolution operator.

J. -D. Hoernel

We prove some existence and uniqueness results and some qualitative properties for the solution of a system modelling the catalytic conversion in a cylinder. This model couples parabolic partial differential equations posed in a cylindrical domain and on its boundary.

Chunjin Lin, Jean-Francois Coulombel, Thierry Goudon

We study a model of radiating gases that describes the interaction of an inviscid gas with photons. We show the existence of smooth traveling waves called 'shock profiles', when the strength of the shock is small. Moreover, we prove that the regularity of the traveling wave increases when the strength of the shock tends to zero.

B. Brighi, J. -D. Hoernel

The aim of this paper is to investigate, as precisely as possible, a boundary value problem involving a third order ordinary differential equation. Its solutions are the similarity solutions of a problem arising in the study of the phenomenon of high frequency excitation of liquid metal systems in an antisymmetric magnetic field within the framework of bound

Thane E. Plambeck

We survey recent developments in the theory of impartial combinatorial games in misere play, focusing on how the Sprague-Grundy theory of normal-play impartial games generalizes to misere play via the indistinguishability quotient construction.

R. Dumitru, C. Peligrad

We define the notion of invariant derivation of a C*-algebra under a compact quantum group action and prove that in certain conditions, such derivations are generators of one parameter automorphism groups.

H. Z. Munthe-Kaas, W. M. Wright

A commutative but not cocommutative graded Hopf algebra $\Hn$, based on ordered rooted trees, is studied. This Hopf algebra generalizes the Hopf algebraic structure of unordered rooted trees $\Hc$, developed by Butcher in his study of Runge--Kutta methods and later rediscovered by Connes and Moscovici in the context of non-commutative geometry and by Kreimer

Patrick Cattiaux, Arnaud Guillin

In this paper we derive non asymptotic deviation bounds for $$¶_ν(|\frac 1t \int_0^t V(X_s) ds - \int V dμ| \geq R)$$ where $X$ is a $μ$ stationary and ergodic Markov process and $V$ is some $μ$ integrable function. These bounds are obtained under various moments assumptions for $V$, and various regularity assumptions for $μ$. Regularity means here that $μ$

Nikolai Nikolov, Peter Pflug

We prove that the $(2n-1)$-th Kobayashi pseudometric of any domain $D\subset\Bbb C^n$ coincides with the Kobayashi--Buseman pseudometric of $D,$ and that $2n-1$ is the optimal number, in general.

Cristina Martinez Ramirez

We compute the degree of the variety parametrizing rational ruled surfaces of degree d in the projective space by relating the problem to Gromov-Witten invariants and Quantum cohomology.

Mattias Dahl

On a compact spin manifold we study the space of Riemannian metrics for which the Dirac operator is invertible. The first main result is a surgery theorem stating that such a metric can be extended over the trace of a surgery of codimension at least three. We then prove that if non-empty the space of metrics with invertible Dirac operators is disconnected in

Michael Voit

Bessel-type convolution algebras of bounded Borel measures on the matrix cones of positive semidefinite $q\times q$-matrices over $\mathbb R, \mathbb C, \mathbb H$ were introduced recently by Rösler. These convolutions depend on some continuous parameter, generate commutative hypergroup structures and have Bessel functions of matrix argument as characters. H

Carlos Castano-Bernard

Certain identities of Ramanujan may be succinctly expressed in terms of the rational function w_N(g) = w_N(f) - 1/w_N(f) on the modular curve X_0(N), where f is a certain modular unit on the Nebentypus cover X_χ(N) introduced by Ogg and Ligozat for N prime congruent to 1 (mod 4) and w_N is the Fricke involution. These correspond to levels N = 5, 13, where th

Illya I. Reznykov, Vitaliy I. Sushchansky

We consider the sequence ${J_m,m \ge 2}$ of the 3-state Mealy automata over an m-symbol alphabet such that the growth function of $J_m$ has the intermediate growth order $[n ^{{\log n}/{2 \log m}} ]$. For each automaton $J_m$ we describe the automaton transformation monoid $S_{J_m}$, defined by it, provide generating series for the growth functions, and cons

S. Sethuraman

Correction to Annals of Probability 28 (2000) 277--302 [doi:10.1214/aop/1019160120].

Teddy Seidenfeld, Mark J. Schervish, Joseph B. Kadane

Correction to Annals of Probability 29 (2001) 1612--1624 [doi:10.1214/aop/1015345764].

Filippo Bracci, Dmitri Zaitsev

We study jets of germs of holomorphic maps between two strongly pseudoconvex domains under the condition that the image of one domain is contained into the other and a given boundary point is (non-tangentially) mapped to a given boundary point. We completely characterize the (non-tangential) 1-jets. Moreover we give algebraic inequalities (in terms of Chern-

S. Klainerman, I. Rodnianski

The paper is concerned with regularity properties of boundaries of causal pasts of points in a 3+1-dimensional Einstein-vacuum spacetime. In a Lorentzian manifold such boundaries play crucial role in propagation of linear and nonlinear waves. We prove a uniform lower bound on the radius of injectivity of these null boundaries in terms of the Riemann curvatur

S. Klainerman, I. Rodnianski

We propose a geometric construction of a first order physical space parametrix for solutions to covariant, tensorial wave equations on a curved background. We describe its applications to a large data breakdown criterion in General Relativity and also give a new gauge independent proof of the Eardley-Moncrief result on large data global existence result for

Yu Yan

Motivated by the prescribing scalar curvature problem, we study the equation $Δ_g u +Ku^p=0 (1+ζ\leq p \leq \frac{n+2}{n-2})$ on locally conformally flat manifolds $(M,g)$ with $R(g)=0$. We prove that when $K$ satisfies certain conditions and the dimension of $M$ is 3 or 4, any solution $u$ of this equation with bounded energy has uniform upper and lower bou

Sankaran Viswanath

The principal objects studied in this note are Coxeter groups $W$ that are neither finite nor affine. A well known result of de la Harpe asserts that such groups have exponential growth. We consider quotients of $W$ by its parabolic subgroups and by a certain class of reflection subgroups. We show that these quotients have exponential growth as well. To achi

Constantin M. Petridi

We prove that for any positive integer c and any s > 0 there are representations of c as a sum a+b of two coprime positive integers a, b, such that the respective radicals are all greater than K(s)R(c)^(1-s)c^2. For the reprasentations in question, this is a stronger result than the abc-conjecture, which postulates that these representations are greater than

Raul Cordovil, David Forge

A family C of circuits of a matroid M is a linear class if, given a modular pair of circuits in C}, any circuit contained in the union of the pair is also in C. The pair (M,C) can be seen as a matroidal generalization of a biased graph. We introduce and study an Orlik-Solomon type algebra determined by (M,C). If C is the set of all circuits of M this algebra

Philippe Monnier, Nguyen Tien Zung

We study formal and analytic normal forms of radial and Hamiltonian vector fields on Poisson manifolds near a singular point.

Oleg R. Musin

The kissing number k(3) is the maximal number of equal size nonoverlapping spheres in three dimensions that can touch another sphere of the same size. This number was the subject of a famous discussion between Isaac Newton and David Gregory in 1694. The first proof that k(3)=12 was given by Schütte and van der Waerden only in 1953. In this paper we present a

Raghunath Acharya

We revisit Bjorken's model of spontaneous breakdown of Lorentz invariance. We show that the model possesses zero mass, spin zero (scalar) Nambu-Goldstone boson, in addition to the zero mass, spin one (vector) photon.

Bruno Durin

In this thesis time-dependent configurations are studied in the formalism of first-quantized string. These configurations are exact: solutions of the corresponding two-dimensional conformal field theory can be found. We can compute perturbative string amplitudes and try to understand the interplay between the time-dependent geometry and the quantized string.

M. V. Ioffe, J. Mateos Guilarte, P. A. Valinevich

Two known 2-dim SUSY quantum mechanical constructions - the direct generalization of SUSY with first-order supercharges and Higher order SUSY with second order supercharges - are combined for a class of 2-dim quantum models, which {\it are not amenable} to separation of variables. The appropriate classical limit of quantum systems allows us to construct SUSY

M. V. Ioffe, S. Kuru, J. Negro, L . M. Nieto

A two-dimensional Pauli Hamiltonian describing the interaction of a neutral spin-1/2 particle with a magnetic field having axial and second order symmetries, is considered. After separation of variables, the one-dimensional matrix Hamiltonian is analyzed from the point of view of supersymmetric quantum mechanics. Attention is paid to the discrete symmetries

Renata Kallosh

We describe the ``action-angle'' integrable system underlying the structure of double-extremal black holes. This implies the existence of a canonical transformation from BPS to non-BPS black holes. We give examples of such canonical transformation for STU and for E(7(7))-invariant black holes

John Collins, Alejandro Perez, Daniel Sudarsky

The notion that gravitation might lead to a breakdown of standard space-time structure at small distances, and that this might affect the propagation of ordinary particles has led to a program to search for violations of Lorentz invariance as a probe of quantum gravity. Initially it was expected that observable macroscopic effects caused by microscopic viola

Walter Winter

I summarize the current understanding of the neutrino oscillation physics with a neutrino factory and a beta beam, where I emphasize more recent phenomenological developments.

Ajay Kumar Rai, J N Pandya, P C Vinodkumar

Di-hadronic molecules such as di-meson, meson-baryon and di-baryon states are studied in the relativistic confinement model. We have computed the binding energy of the di-hadronic systems like $K-N$, $Π-N$, $ρ-N$ etc., as penta-quark states, 2$π$, $ρ-ρ$, $K-K^*$, $K^*-K^*$, $D-D^*$ etc. as tetra-quark states and $N-N$, $N-Δ$, $Δ-Δ$ etc. as di-baryonic states

B. I. Ermolaev, M. Greco, S. I. Troyan

Explicit expressions for the non-singlet and singlet structure functions g_1 in the small-x region are obtained. They include the total resummation of the double- and single- logarithms of x and account for the running QCD coupling effects. Both the non-singlet and singlet structure functions are Regge behavied asymptotically, with the intercepts predicted i

Mohammad Saleem, Muhammad Ali, Shaukat Ali

The standard model for electroweak interactions uses the concepts of weak hypercharge and local gauge invariance of the Lagrangian density under the gauge group SU(2) x U(1). Taylor has remarked that U(1), being a multiply-connected group, in general, should have different coupling strengths for singlets and doublets. But in the development of the standard m

Hai-Yang Cheng

The status of exclusive two-body and three-body baryonic B decays is reviewed. The threshold enhancement effect in the dibaryon invariant mass and the angular distributions in the dibaryon rest frame are stressed and explained. Weak radiative baryonic B decays mediated by the electromagnetic penguin process $b\to sγ$ are discussed. Puzzles with the correlati

S. Datta, A. Jakovac, F. Karsch, P. Petreczky

We discuss lattice results on the properties of finite momentum charmonium states in a gluonic plasma. We also present preliminary results for bottomonium correlators and spectral functions in the plasma. Significant modifications of chi_b states are seen at temperatures of 1.5 Tc.

Heavy Flavor Averaging Group, E. Barberio, I. Bizjak, S. Blyth

This article reports world averages for measurements on b-hadron properties obtained by the Heavy Flavor Averaging Group (HFAG) using the available results as of at the end of 2005. In the averaging, the input parameters used in the various analyses are adjusted (rescaled) to common values, and all known correlations are taken into account. The averages incl

D0 Collaboration

We present the measurement of R = B(t->Wb)/B(t->Wq) in ppbar collisions at sqrt(s) = 1.96 TeV, using 230 pb-1 of data collected by the DO experiment at the Fermilab Tevatron Collider. We fit simultaneously R and the number of selected top quark pairs (ttbar), to the number of identified b-quark jets in events with one electron or one muon, three or more jets

V. S. Manko, J. Martin, E. Ruiz

The analysis of singular regions in the NUT solutions carried out in the recent paper (Manko and Ruiz, 2005 Class. Quantum Grav. 22, p.3555) is now extended to the Demianski-Newman vacuum and electrovacuum spacetimes. We show that the effect which produces the NUT parameter in a more general situation remains essentially the same as in the purely NUT solutio

Louis Crane

We explore the possibility of replacing point set topology by higher category theory and topos theory as the foundation for quantum general relativity. We discuss the BC model and problems of its interpretation, and connect with the construction of causal sites.

R. M. Kiehn

This article examines how the physical presence of field energy and particulate matter could influence the topological properties of space time. The theory is developed in terms of vector and matrix equations of exterior differential forms. The topological features and the dynamics of such exterior differential systems are studied with respect to processes o

P. A. Castillo, M. G. Arenas, J. G. Castellano, J. J. Merelo

Hybrid neuro-evolutionary algorithms may be inspired on Darwinian or Lamarckian evolu- tion. In the case of Darwinian evolution, the Baldwin effect, that is, the progressive incorporation of learned characteristics to the genotypes, can be observed and leveraged to improve the search. The purpose of this paper is to carry out an exper- imental study into how

Michel Fliess

Thanks to the nonstandard formalization of fast oscillating functions, due to P. Cartier and Y. Perrin, an appropriate mathematical framework is derived for new non-asymptotic estimation techniques, which do not necessitate any statistical analysis of the noises corrupting any sensor. Various applications are deduced for multiplicative noises, for the length

Alois Schlögl

BioSig is an open source software library for biomedical signal processing. Most users in the field are using Matlab; however, significant effort was undertaken to provide compatibility to Octave, too. This effort has been widely successful, only some non-critical components relying on a graphical user interface are missing. Now, installing BioSig on Octave

Supriyo Datta

In this paper we present a general formulation for electronic transport that combines strong correlation effects with broadening and quantum coherence, and illustrate it with a simple example ("spin blockade") that clearly demonstrates all three effects. The standard master equation method for Coulomb blockade captures the first effect, while a numbe

N. V. Pimparkar, S. Kumar, J. Y. Murthy, M. A. Alam

By generalizing the classical linear response theory of stick percolation to nonlinear regime, we find that the drain current of a Nanobundle Thin Film Transistor (NB-TFT) is described under a rather general set of conditions by a universal scaling formula ID = A/LS g(LS/LC, rho_S * LS * LS) f(VG, VD), where A is a technology-specific constant, g is function

C. R. dela Cruz, F. Yen, B. Lorenz, M. M. Gospodinov

Strong anomalies of the thermal expansion coefficients at the magnetic and ferroelectric transitions have been detected in multiferroic $RMn_2O_5$. Their correlation with anomalies of the specific heat and the dielectric constant is discussed. The results provide evidence for the magnetic origin of the ferroelectricity mediated by strong spin-lattice couplin

S. M. Shapiro, G. Xu, G. Gu, J. Gardner

Nb-Ru is a high temperature shape memory alloy that undergoes a Martensitic transformation from a parent cubic b-phase into a tetragonal b' phase at TM 900 C. Measurements of the phonon dispersion curves show that the [110]-TA2 phonon branch, corresponding in the q=0 limit to the elastic constant C'=1/2(C11-C12) has an anomalous temperature dependenc

Wei Zhang, H. A. Fertig

Recent studies of the two-dimensional, classical $XY$ magnet in a magnetic field suggest that it has three distinct vortex phases: a linearly confined phase, a logarithmically confined phase, and a free vortex phase. In this work we study spin-spin correlation functions in this model by analytical analysis and numerical simulations to search for signatures o

Michael P. Allen

A method for calculating the pressure tensor in constant-volume Monte Carlo simulations of convex bodies is presented. In contrast to other approaches, the method requires only an isotropic scaling of the simulation box, and the counting of simple geometric quantities characterizing overlapping pairs. Non-sphericity presents no special difficulties. The resu

S. G. Magalhaes, F. M. Zimmer, B. Coqblin

A theory is proposed to describe the competition among antiferromagnetism (AF), spin glass (SG) and Kondo effect. The model describes two Kondo sublattices with an intrasite Kondo interaction strength $J_{K}$ and an interlattice quantum Ising interaction in the presence of a transverse field $Γ$. The interlattice coupling is a random Gaussian distributed var

N. Bontemps, R. P. S. M. Lobo, A. F. Santander-Syro, A. Zimmers

The optical conductivity of CuO2 (copper-oxygen) planes in p- and n-type cuprates thin films at various doping levels is deduced from highly accurate reflectivity data. The temperature dependence of the real part sigma1(omega) of this optical conductivity and the corresponding spectral weight allow to track the opening of a partial gap in the normal state of

C. -H. Yang, T. Y. Koo, S. -H. Lee, C. Song

Epitaxial thin films of multiferroic perovskite BiMnO3 were synthesized on SrTiO3 substrates, and orbital ordering and magnetic properties of the thin films were investigated. The ordering of the Mn^{3+} e_g orbitals at a wave vector (1/4 1/4 1/4) was detected by Mn K-edge resonant x-ray scattering. This peculiar orbital order inherently contains magnetic fr

Joo-Von Kim

We present a stochastic theory of linewidths for magnetization oscillations in spin-valve structures driven by spin-polarized currents. Starting from a nonlinear oscillator model derived from spin-wave theory, we derive Langevin equations for amplitude and phase fluctuations due to the presence of thermal noise. We find that the spectral linewidths are inver

O. Usmani, Ya. M. Blanter, Yu. V. Nazarov

We demonstrate the feasibility of a strong feedback regime for a single-electron tunneling device weakly coupled to an underdamped single-mode oscillator. In this regime, mechanical oscillations are generated and the current is strongly modified whereas the current noise is parametrically big with respect to the Poisson value. This regime requires energy dep

S. R. Mishra, S. P. Ram, Arup Banerjee

We have theoretically studied the collective modes of a quasi two-dimensional (Q2D) Bose condensate in the large gas parameter regime by using a formalism which treats the interaction energy beyond the mean-field approximation. In the calculation we use the perturbative expansion for the interaction energy by incorporating the Lee, Huang and Yang (LHY) corre

L. Ejsing, K. Smistrup, C. M. Pedersen, N. A. Mortensen

Using a Fourier approach we offer a general solution to calculations of slip velocity within the circuit description of the electro-hydrodynamics in a binary electrolyte confined by a plane surface with a modulated surface potential. We consider the case with a spatially constant intrinsic surface capacitance where the net flow rate is in general zero while

K. Ohishi, W. Higemoto, A. Koda, S. R. Saha

Local magnetic fields in a molecule-based optically chiral magnet [Cr(CN)$_6$][Mn($S$)-pnH(H$_2$O)](H$_2$O) (GN-S) and its enantiomer (GN-R) are studied by means of muon spin rotation and relaxation (muSR). Detailed analysis of muon precession signals under zero field observed below T_c supports the average magnetic structure suggested by neutron powder diff

V. L. Gurtovoi, S. V. Dubonos, A. V. Nikulov, N. N. Osipov

The quantum oscillations of the dc voltage are induced on segments of asymmetric superconducting loops by an external ac current or noise. The dependencies of the amplitude of the quantum oscillations on amplitude of inducing ac current are measured at different temperatures below superconducting transition Tc on aluminum asymmetric loops and systems of the

Jerome Dorignac, Agnieszka Kalinowski, Shyamsunder Erramilli, Pritiraj Mohanty

Dynamical response of nanomechanical cantilever structures immersed in a viscous fluid is important to in vitro single-molecule force spectroscopy, biomolecular recognition of disease-specific proteins, and the detection of microscopic dynamics of proteins. Here we study the stochastic response of biofunctionalized nanomechanical cantilevers beam in a viscou

A. A. Burlakov, V. L. Gurtovoi, S. V. Dubonos, A. V. Nikulov

The Little-Parks oscillations of the resistance and the quantum oscillations of the rectified voltage observed for asymmetric superconducting Al rings give experimental evidence of two degenerate energy states at the magnetic flux $Φ_{0}$/2. The quantum oscillations of the critical current as a function of magnetic field have also been measured. On the one h

A. I. Olemskoi

We consider the self-similar phase space with reduced fractal dimension $d$ being distributed within domain $0<d<1$ with spectrum $f(d)$. Related thermostatistics is shown to be governed by the Tsallis&#39; formalism of the non-extensive statistics, where role of the non-additivity parameter plays inverted value ${\barτ}(q)\equiv 1/τ(q)>1$ of the multifracta

N. Nemec, D. Tomanek, G. Cuniberti

We combine ab initio density functional theory with transport calculations to provide a microscopic basis for distinguishing between good and poor metal contacts to nanotubes. Comparing Ti and Pd as examples of different contact metals, we trace back the observed superiority of Pd to the nature of the metal-nanotube hybridization. Based on large scale Landau

Martin Michael Mueller, Markus Deserno, Jemal Guven

Particles bound to an interface interact because they deform its shape. The stresses that result are fully encoded in the geometry and described by a divergence-free surface stress tensor. This stress tensor can be used to express the force on a particle as a line integral along any conveniently chosen closed contour that surrounds the particle. The resultin

M A N Araujo, N M R Peres

Within the Hartree Fock- RPA analysis, we derive the spin wave spectrum for the weak ferromagnetic phase of the Hubbard model on the honeycomb lattice. Assuming a uniform magnetization, the polar (optical) and acoustic branches of the spin wave excitations are determined. The bipartite lattice geometry produces a q-dependent phase difference between the spin

Augustin Baas, Jean-Philippe Karr, Marco Romanelli, Alberto Bramati

We investigate experimentally one of the main features of a quantum fluid constituted by exciton polaritons in a semiconductor microcavity, that is quantum degeneracy of a macroscopic fraction of the particles. We show that resonant pumping allows to create a macroscopic population of polaritons in one quantum state. Furthermore we demonstrate that parametri

T. Rettig, S. Brittain, Theodore Simon, E. Gibb

We present high-resolution infrared spectra of four YSOs (T Tau N, T Tau S, RNO 91, and HL Tau). The spectra exhibit narrow absorption lines of 12CO, 13CO, and C18O as well as broad emission lines of gas phase12CO. The narrow absorption lines of CO are shown to originate from the colder circumstellar gas. We find that the line of sight gas column densities r

A. Bonanno, V. Urpin, G. Belvedere

We discuss the mean-field dynamo action in protoneutron stars that are subject to instabilities during the early evolutionary phase. The mean field is generated in the neutron-finger unstable region where the Rossby number is $\sim 1$ and mean-field dynamo is efficient. Depending on the rotation rate, the mean-field dynamo can lead to the formation of three

Paul J. Green

Spectral differences between lensed quasar image components are common. Since lensing is intrinsically achromatic, these differences are typically explained as the effect of either microlensing, or as light path time delays sampling intrinsic quasar spectral variability. Here we advance a novel third hypothesis: some spectral differences are due to small lin

H. Hernandez-Toledo, V. Avila-Reese, J. R. Salazar-Contreras, C. J. Conselice

We present a photometric and structural analysis of 42 E/S0 galaxies in (E/S0 + S) pairs observed in the BVRI color bands. We empirically determine the effects of interactions on their morphology, structure and stellar populations as seen from the light concentration (C), asymmetry (A), and clumpiness (S) parameters. We further compare these values to a cont

Carol Lonsdale, Duncan Farrah, Harding Smith

Ever since their discovery in the 1970&#39;s, UltraLuminous InfraRed Galaxies (ULIRGs; classically Lir>10^12Lsun) have fascinated astronomers with their immense luminosities, and frustrated them due to their singularly opaque nature, almost in equal measure. Over the last decade, however, comprehensive observations from the X-ray through to the radio have pr

K. Katarzynski, G. Ghisellini, F. Tavecchio, J. Gracia

Recent gamma-ray observations of the blazar 1ES 1101-232 (redshift z=0.186) reveal that the unabsorbed TeV spectrum is hard, with spectral index $α\lesssim 0.5$ [$F(ν) \propto ν^{-α}$]. We show that simple one-zone synchrotron self-Compton model can explain such hard spectra if we assume a power law energy distribution of the emitting electrons with a relati

Roberto Soria, Rob Fender, Diana Hannikainen, Andrew Read

We studied the radio source associated with the ultraluminous X-ray source in NGC 5408 (L_X ~ 10^{40} erg/s). The radio spectrum is steep (index ~ -1), consistent with optically-thin synchrotron emission, not with flat-spectrum core emission. Its flux density (~ 0.28 mJy at 4.8 GHz, at a distance of 4.8 Mpc) was the same in the March 2000 and December 2004 o

Sylvain Veilleux

This paper reviews the recent results from a comprehensive investigation of the most luminous mergers in the local universe, the ultraluminous infrared galaxies (ULIRGs) and the quasars. First, the frequency of occurrence and importance of black hole driven nuclear activity in ULIRGs are discussed using the latest sets of optical, near-infrared, mid-infrared

L. M. Rebull, J. R. Stauffer, S. V. Ramirez, E. Flaccomio

Chandra observations of solar-like pre-main sequence (PMS) stars in the Orion Flanking Fields (age ~1 Myr) and NGC 2264 (~3 Myr) are compared with the results of the COUP survey of similar objects in the ONC (~0.5 Myr). The correlations between log Lx and mass found for PMS stars on convective tracks in these clusters are consistent with the relationships fo

Mark R. Krumholz

Star formation generally proceeds inside-out, with overdense regions inside protostellar cores collapsing rapidly and progressively less dense regions following later. Consequently, a small protostar will form early in the evolution of a core, and collapsing material will fall to the protostellar surface and radiate away its gravitational potential energy. T

Schuyler D. Van Dyk, Weidong Li, Alexei V. Filippenko, Roberta M. Humphreys

We show that Supernova (SN) 2002kg in NGC 2403, initially classified as Type II-narrow (IIn), has photometric and spectroscopic properties unlike those of normal SNe. Its behavior, instead, is more typical of highly massive stars which experience the short-lived luminous blue variable (LBV) phase toward the end of their lives. The star, in fact, most resembl

C. A. Rodriguez-Rico, W. M. Goss, J. -H. Zhao, Y. Gomez

We present new Very Large Array (VLA) observations toward NGC 253 of the recombination line H53alpha (43 GHz) at an angular resolution of 1.&#39;&#39;5 X 1.&#39;&#39;0. The free-free emission at 43 GHz is estimated to be ~100 mJy, implying a star formation rate of ~1.3 Msun/yr in the nuclear region of this starburst galaxy. A reanalysis is made for previousl

Xiao-Jun Bi, Hong-Bo Hu, Xinmin Zhang

The CACTUS experiment recently observed a gamma ray excess above 50 GeV from the direction of the Draco dwarf spheroidal galaxy. Considering that Draco is dark matter dominated the gamma rays may be generated through dark matter annihilation in the Draco halo. In the framework of the minimal supersymmetric extension of the standard model we explore the param

The H. E. S. S. Collaboration, :, F. A. Aharonian

The origin of Galactic cosmic rays (with energies up to 10^15 eV) remains unclear, though it is widely believed that they originate in the shock waves of expanding supernova remnants. Currently the best way to investigate their acceleration and propagation is by observing the gamma-rays produced when cosmic rays interact with interstellar gas. Here we report

F. Royer, P. North, C. Melo, J. -C. Mermilliod

We show the vsini distribution of main sequence B stars in sites of various metallicities, in the absolute magnitude range -3.34 < Mv < -2.17. These include Galactic stars in the field measured by Abt et al. (2002), members of the h & chi Per open clusters measured by North et al. (2004), and five fields in the SMC and LMC measured at ESO Paranal with the FL