October 2005 arXiv papers — page 14
Showing 1,301–1,400 of 4,503 papers
hbar expansions in semiclassical theories for systems with smooth potentials and discrete symmetries
nlin.CDHolger Cartarius, Jörg Main, Günter Wunner
We extend a theory of first order hbar corrections to Gutzwiller's trace formula for systems with a smooth potential to systems with discrete symmetries and, as an example, apply the method to the two-dimensional hydrogen atom in a uniform magnetic field. We exploit the C_{4v}-symmetry of the system in the calculation of the correction terms. The numeric
Superconductivity mediated by a soft phonon mode: specific heat, resistivity, thermal expansion and magnetization of YB6
cond-mat.supr-conR. Lortz, Y. Wang, U. Tutsch, S. Abe
The superconductor YB6 has the second highest critical temperature Tc among the boride family MBn. We report measurements of the specific heat, resistivity, magnetic susceptibility and thermal expansion from 2 to 300 K, using a single crystal with Tc = 7.2 K. The superconducting gap is characteristic of medium-strong coupling. The specific heat, resistivity
N. Phan-Bao, M. S. Bessell, E. L. Martin, G. Simon
We report the discovery of a new M9.0 dwarf at only 8.2 pc, which we identified in our search for nearby ultracool dwarf (I-J >= 3.0, later than M8.0) in the DENIS database. We measure a very high proper motion of 2.5 arc-sec/yr. The PC3 index measured from its low-resolution spectrum gives a spectrophotometric distance of 8.2 pc. This makes it the third clo
Corrections to the Fine Structure Constant in the Spacetime of a Cosmic String from the Generalized Uncertainty Principle
hep-thForough Nasseri
We calculate the corrections to the Fine Structure Constant in the spacetime of a cosmic string. These corrections stem from the generalized uncertainty principle. In the absence of a cosmic string our result here is in agreement with our previous result.
Tomoki Endo, Toshiki Maruyama, Satoshi Chiba, Toshitaka Tatsumi
The Coulomb interaction effect and the surface effect are consistently taken into account in the hadron-quark mixed phase. These two finite-size effects greatly change the properties of the mixed phase and restrict its density region. In particular, the charge screening effect and the rearrangement of the charged particles are elucidated. Keeping the Gibbs c
M. T. L. Hsu, A. Dantan, J. Cviklinski, A. Bramati
The traversal of an elliptically polarized optical field through a thermal vapour cell can give rise to a rotation of its polarization axis. This process, known as polarization self-rotation (PSR), has been suggested as a mechanism for producing squeezed light at atomic transition wavelengths. In this paper, we show results of the characterization of PSR in
Ki-Seok Kim
We reinvestigate the bandwidth-control and doping-control Mott transitions (BCMT and DCMT) from a spin liquid Mott insulator to a Fermi liquid metal based on the slave-rotor representation of the Hubbard model,\cite{Florens} where the Mott transitions are described by softening of bosonic collective excitations. We find that the nature of the insulating phas
Shin'ichi Nojiri, Sergei D. Odintsov, O. G. Gorbunova
The solution of dark energy problem in the models without scalars is presented. It is shown that late-time accelerating cosmology may be generated by the ideal fluid with some implicit equation of state. The universe evolution within modified Gauss-Bonnet gravity is considered. It is demonstrated that such gravitational approach may predict the (quintessenti
Spectral distortions to the Cosmic Microwave Background from the recombination of hydrogen and helium
astro-phWan Yan Wong, Sara Seager, Douglas Scott
The recombination of hydrogen and helium at z~1000-7000 gives unavoidable distortions to the Cosmic Microwave Background (CMB) spectrum. We present a detailed calculation of the line intensities arising from the Ly-alpha (2p-1s) and two-photon (2s-1s) transitions for the recombination of hydrogen, as well as the corresponding lines from helium. We give an ap
Piet Hut, Mark Alford, Max Tegmark
We discuss the nature of reality in the ontological context of Penrose's math-matter-mind triangle. The triangle suggests the circularity of the widespread view that math arises from the mind, the mind arises out of matter, and that matter can be explained in terms of math. Non-physicists should be wary of any claim that modern physics leads us to any pa
S. Khoroshkin, A. Varchenko
Let $C$ be an arrangement of affine hyperplanes in a complex affine space $X$, $D$ the ring of algebraic differential operators on $X$. We define a category of quivers associated with $C$. A quiver is a collection of vector spaces, attached to strata of the arrangement, and suitable linear maps between the vector spaces . To a quiver we assign a $D$-module o
Joshua Wilkie, Ray Ng
Non-Markovian quantum state diffusion (NMQSD) is a non-relativistic but otherwise exact theory which expresses the reduced density matrix of an arbitrary subsystem, interacting linearly with an uncoupled harmonic oscillator bath, as an average of diadics formed from state vectors which obey stochastic variational-differential equations. The vacuum radiation
Optimum measurement for unambiguously discriminating two mixed states: General considerations and special cases
quant-phUlrike Herzog, Janos A. Bergou
Based on our previous publication [U. Herzog and J. A. Bergou, Phys.Rev. A 71, 050301(R) (2005)] we investigate the optimum measurement for the unambiguous discrimination of two mixed quantum states that occur with given prior probabilities. Unambiguous discrimination of nonorthogonal states is possible in a probabilistic way, at the expense of a nonzero pro
X. X. Yi, D. P. Liu, W. Wang
Through the quantum trajectory approach, we calculate the geometric phase acquired by a bipartite system subjected to decoherence. The subsystems that compose the bipartite system interact with each other, and then are entangled in the evolution. The geometric phase due to the quantum jump for both the bipartite system and its subsystems are calculated and a
Jing Zhang, Changde Xie, Kunchi Peng
We propose a scheme of continuous-variable reversible telecloning, which broadcast the information of an unknown state without loss from a sender to several spatially separated receivers exploiting multipartite entanglement as quantum channels. In this scheme, quantum information of an unknown state is distributed into $M$ optimal clones and $M-1$ anticlones
Does consciousness really collapse the wave function? A possible objective biophysical resolution of the measurement problem
quant-phFred H. Thaheld
An analysis has been performed of the theories and postulates advanced by von Neumann, London and Bauer, and Wigner, concerning the role that consciousness might play in the collapse of the wave function, which has become known as the measurement problem. This reveals that an error may have been made by them in the area of biology and its interface with quan
Panos Aliferis, Daniel Gottesman, John Preskill
We prove a new version of the quantum threshold theorem that applies to concatenation of a quantum code that corrects only one error, and we use this theorem to derive a rigorous lower bound on the quantum accuracy threshold epsilon_0. Our proof also applies to concatenation of higher-distance codes, and to noise models that allow faults to be correlated in
Radhakrishnan Nagarajan, Meenakshi Upreti
Techniques such as detrended fluctuation analysis (DFA) and its extensions have been widely used to determine the nature of scaling in nucleotide sequences. In this brief communication we show that tandem repeats which are ubiquitous in nucleotide sequences can prevent reliable estimation of possible long-range correlations. Therefore, it is important to inv
P. Cheinet, B. Canuel, F. Pereira Dos Santos, A. Gauguet
We present here an analysis of the sensitivity of a time-domain atomic interferometer to the phase noise of the lasers used to manipulate the atomic wave-packets. The sensitivity function is calculated in the case of a three pulse Mach-Zehnder interferometer, which is the configuration of the two inertial sensors we are building at BNM-SYRTE. We successfully
Hydrosomes: Optically trapped femtoliter containers for single molecule studies and microfluidics
physics.bio-phJ. E. Reiner, A. M. Crawford, R. B. Kishore, Lori. S. Goldner
We demonstrate a novel technique for creating, manipulating, and combining femtoliter volume chemical containers. Possible uses include creating controlled chemical reactions involving small quantities of reagent, and studying the dynamics of single molecules within the containers by fluorescence imaging techniques. The containers, which we call hydrosomes,
Gary A. Dilts
Numerical simulations of compressible fluid flows require an equation of state (EOS) to relate the thermodynamic variables of density, internal energy, temperature, and pressure. A valid EOS must satisfy the thermodynamic conditions of consistency (derivation from a free energy) and stability (positive sound speed squared). When phase transitions are signifi
Maciej Kurant, Patrick Thiran
Many complex networks are only a part of larger systems, where a number of coexisting topologies interact and depend on each other. We introduce a layered model to facilitate the description and analysis of such systems. As an example of its application we study the load distribution in three real-life transportation systems, where the lower layer is the phy
M. Vogel, D. F. A. Winters, D. M. Segal, R. C. Thompson
We propose a novel type of precision laser spectrometer for trapped, highly charged ions nearly at rest. It consists of a cylindrical open-endcap Penning trap in which an externally produced bunch of highly charged ions can be confined and investigated by means of laser spectroscopy. The combination of confinement, cooling and compression of a dense ion clou
Non-contact atomic force microscopy: Stability criterion and dynamical responses of the shift of frequency and damping signal
physics.atm-clusGérard Couturier, Rodolphe Boisgard, Laurent Nony, Jean-Pierre Aimé
The aim of this article is to provide a complete analysis of the behavior of a noncontact atomic force microscope (NC-AFM). We start with a review of the equations of motion of a tip interacting with a surface in which the stability conditions are first revisited for tapping mode. Adding the equations of automatic gain control (AGC), which insures constant a
A. Costa
The rheological properties of suspensions containing high solid fractions are investigated. Attention is focused on viscosity of silicate and magmatic melt systems. A general empirical equation which describes the relative viscosity of suspensions as a function of suspended solid fraction is proposed. In the limit of very dilute solid concentrations it reduc
Study Influence of Doping on Temperature Dependence of Diffusion Rate in Organic Molecular Crystals
physics.opticsM. A. Korshunov
It is experimentally shown, that doping an organic molecular crystal reduces diffusion rate of impurity. Also reduces its influence on a modification of temperature. Examinations are lead on a crystal paradibromobenzene doping by paradiclorobenzene. Diffusing impurity was parabromochlorobenzene.
T. Esirkepov, M. Yamagiwa, T. Tajima
The ion acceleration driven by a laser pulse at intensity $I = 10^{20} - 10^{22} $W/cm$^2\times(μ$m$/λ)^2$ from a double layer target is investigated with multi-parametric Particle-in-Cell (PIC) simulations. For targets with a wide range of thickness $l$ and density $n_e$, at given intensity the highest ion energy gain occurs at certain {\it critical depth}
Gary Oas
The concept of velocity dependent mass, relativistic mass, is examined and is found to be inconsistent with the geometrical formulation of special relativity. This is not a novel result; however, many continue to use this concept and some have even attempted to establish it as the basis for special relativity. It is argued that the oft-held view that formula
J. Meng, J. Peng, S. Q. Zhang, S. -G. Zhou
Adiabatic and configuration-fixed constraint triaxial relativistic mean field (RMF) approaches are developed for the first time and a new phenomenon, the existence of multi chiral-doublets (M$χ$D), i.e., more than one pairs of chiral doublets bands in one single nucleus, is suggested for nuclei in A~100 region, typically for $^{106}$Rh, based on the triaxial
David d'Enterria
I review the main experimental results on jet physics in high-energy nucleus-nucleus collisions as studied via inclusive leading hadron spectra and di-hadron correlations at high transverse momentum. In central Au+Au at RHIC (sqrt(s_NN) = 200 GeV), the observed large suppression of high-$p_T$ hadron spectra as well as the strongly modified azimuthal dijet co
P. Staszel
We present recent results obtained by the BRAHMS experiment at the Relativistic Heavy Ion Collider (RHIC) for the systems of Au + Au and Cu + Cu at \rootsnn{200} and at 62.4 GeV, and p + p at \rootsnn{200}. Nuclear modification factors for Au + Au and Cu + Cu collisions are presented. Analysis of anti-particle to particle ratios as a function of rapidity and
Gang Wang
We present STAR's measurements of directed flow (v_1) and elliptic flow (v_2) for charged hadrons in AuAu collisions at 62 and 200 GeV, as a function of pseudorapidity, p_t and centrality. v_2 results in CuCu collisions at 200 GeV are also presented.
Jeffery Praught, Roman G. Smirnov
The theory of bi-Hamiltonian systems has its roots in what is commonly referred to as the "Lenard recursion formula". The story about the discovery of the formula told by Andrew Lenard is the subject of this article.
A new model of turbulent relative dispersion: a self-similar telegraph equation based on persistently separating motions
nlin.CDTakeshi Ogasawara, Sadayoshi Toh
Turbulent relative dispersion is studied theoretically with a focus on the evolution of probability distribution of the relative separation of two passive particles. A finite separation speed and a finite correlation of relative velocity, which are crucial for real turbulence, are implemented to a master equation by multiple-scale consideration. A telegraph
Joerg Schumacher, Katepalli R. Sreenivasan
We present direct numerical simulations (DNS) of the mixing of the passive scalar at modest Reynolds numbers (10 =< R_λ=< 42) and Schmidt numbers larger than unity (2 =< Sc =< 32). The simulations resolve below the Batchelor scale up to a factor of four. The advecting turbulence is homogeneous and isotropic, and maintained stationary by stochastic forcing at
S. Berti, D. Vergni, F. Visconti, A. Vulpiani
We present a numerical study of mixing and reaction efficiency in closed domains. In particular we focus our attention on laminar flows. In the case of inert transport the mixing properties of the flows strongly depend on the details of the Lagrangian transport. We also study the reaction efficiency. Starting with a little spot of product we compute the time
L. I. Petrova
A role of skew-symmetric differential forms in mathematical physics relates to the fact that they reflect the properties of conservation laws. The closed exterior forms correspond to the conservation laws for physical fields, whereas the evolutionary forms correspond to the conservation laws for material media. Skew-symmetric differential forms can describe
Yoshiaki Maeda, Dominique Manchon, Sylvie Paycha
This paper has been withdrawn by the authors, as it contains some errors. The core of it has been entirely rewritten in math.FA/0510454.
Shamgar Gurevich, Ronny Hadani
The main goal of this paper is to construct the Hannay-Berry model of quantum mechanics, on a two dimensional symplectic torus. We construct a simultaneous quantization of the algebra of functions and the linear symplectic group $\G =$ SL$_2 (\Z)$. We obtain the quantization via an action of $\G$ on the set of equivalence classes of irreducible representatio
Jose Mijares
We give a parametrization with perfect sets of the abstract Ellentuck theorem. The main tool for achieving this goal is a sort of parametrization of an abstract version of the Nash-Williams theorem. As corollaries, we obtain some known classical results like the parametrized version of the Galvin-Prikry theorem due to Miller and Todorcevic, and the parametri
Gerard Iooss, Dmitry Pelinovsky
We study travelling kinks in the spatial discretizations of the nonlinear Klein--Gordon equation, which include the discrete $ϕ^4$ lattice and the discrete sine--Gordon lattice. The differential advance-delay equation for travelling kinks is reduced to the normal form, a scalar fourth-order differential equation, near the quadruple zero eigenvalue. We show n
Richard F. Bass, Krzysztof Burdzy
We give a simple proof that in a Lipschitz domain in two dimensions with Lipschitz constant one, there is pathwise uniqueness for the Skorokhod equation governing reflecting Brownian motion.
Antar Bandyopadhyay, David Gamarnik
We propose a new type of approximate counting algorithms for the problems of enumerating the number of independent sets and proper colorings in low degree graphs with large girth. Our algorithms are not based on a commonly used Markov chain technique, but rather are inspired by developments in statistical physics in connection with correlation decay properti
Diego Saa
Goedel's results have had a great impact in diverse fields such as philosophy, computer sciences and fundamentals of mathematics. The fact that the rule of mathematical induction is contradictory with the rest of clauses used by Goedel to prove his undecidability and incompleteness theorems is proved in this paper. This means that those theorems are inva
F. Pfender
The visibility graph Vis(X) of a discrete point set X in the plane has vertex set X and an edge xy for every two points x,y\in X whenever there is no other point in X on the line segment between x and y. We show that for every graph G, there is a point set X, such that the subgraph of Vis(X\cup Z^2) induced by X is isomorphic to G. As a consequence, we show
Real Separated Algebraic Curves, Quadrature Domains, Ahlfors Type Functions and Operator Theory
math.SPDmitry V. Yakubovich
The aim of this paper is to inter-relate several algebraic and analytic objects, such as real-type algebraic curves, quadrature domains, functions on them and rational matrix functions with special properties, and some objects from Operator Theory, such as vector Toeplitz operators and subnormal operators. Our tools come from operator theory, but some of our
On the residual solvability of generalized free products of finitely generated nilpotent groups
math.GRD. Kahrobaei
In this paper we study the residual solvability of the generalized free product of finitely generated nilpotent groups. We show that these kinds of structures are often residually solvable.
Sergey Belyi, Seppo Hassi, Henk de Snoo, Eduard Tsekanovskii
New special types of stationary conservative impedance and scattering systems, the so-called non-canonical systems, involving triplets of Hilbert spaces and projection operators, are considered. It is established that every matrix-valued Herglotz-Nevanlinna function of the form V(z)=Q+Lz+\int_{\dR}(\frac{1}{t-z}-\frac{t}{1+t^2})dΣ(t) can be realized as a tra
M. A. Babenko, A. V. Karzanov
A graph (digraph) $G=(V,E)$ with a set $T\subseteq V$ of terminals is called inner Eulerian if each nonterminal node $v$ has even degree (resp. the numbers of edges entering and leaving $v$ are equal). Cherkassky and Lovász showed that the maximum number of pairwise edge-disjoint $T$-paths in an inner Eulerian graph $G$ is equal to $\frac12\sum_{s\in T} λ(s)
Kazuo Habiro
We prove that if n\ge1, then an (n+1)-component Brunnian link L in a connected, oriented 3-manifold is C_n-equivalent to an unlink. We also prove that if n\ge2, then L can not be distinguished from an unlink by any Goussarov-Vassiliev finite type invariant of degree<2n.
Kazuo Habiro
We prove that two links related by a surgery along a connected, strict graph clasper of degree n are C_n-equivalent, i.e, related by a sequence of surgeries along strict tree claspers of degree n.
A. V. Lapteva, E. I. Yakovlev
Let P be a closed triangulated manifold, dim P=n. We consider the group of simplicial 1-chains C_1(P) and the homology group H_1(P). We also use some nonnegative weighting function L on C_1(P). For any homological class from H_1(P) method proposed in article builds a cycle z with minimal weight L(z). The main idea is in using a simplicial scheme of space of
Nobuharu Sawada
Let $S(Λ)$ be the cyclotomic q-Schur algebra associated to the Ariki-Koike algebra $H$. We construct a certain subalgebra $S^0(Λ)$ of $S(Λ)$, and show that it is a standardly based algebra in the sense of Du and Rui. $S^0(Λ)$ has a natural quotient $\bar{S^0}(Λ)$, which turns out to be a cellular algebra. In the case where the modified Ariki-Koike algebra $H
Jean B. Lasserre, Tim Netzer
We show that every real polynomial $f$ nonnegative on $[-1,1]^{n}$ can be approximated in the $l_{1}$-norm of coefficients, by a sequence of polynomials $\{f_{\ep r}\}$ that are sums of squares. This complements the existence of s.o.s. approximations in the denseness result of Berg, Christensen and Ressel, as we provide a very simple and \textit{explicit} ap
Individual-based probabilistic models of adaptive evolution and various scaling approximations
math.PRNicolas Champagnat, Régis Ferrière, Sylvie Méléard
We are interested in modelling Darwinian evolution, resulting from the interplay of phenotypic variation and natural selection through ecological interactions. Our models are rooted in the microscopic, stochastic description of a population of discrete individuals characterized by one or several adaptive traits. The population is modelled as a stochastic poi
Laurence R. Taylor
There are many theorems in the differential geometry literature of the following sort. Let M be a complete Riemannian manifold with some conditions on various curvatures, diameters, volumes, etc. Then M is homotopy equivalent to a finite CW complex, or M is the interior of a compact, topological manifold with boundary. At first glance it seems unlikely that
Wladyslaw A. Majewski, Marcin Marciniak
A map $ϕ:M_m(\bC)\to M_n(\bC)$ is decomposable if it is of the form $ϕ=ϕ_1+ϕ_2$ where $ϕ_1$ is a CP map while $ϕ_2$ is a co-CP map. It is known that if $m=n=2$ then every positive map is decomposable. Given an extremal unital positive map $ϕ:M_2(\bC)\to M_2(\bC)$ we construct concrete maps (not necessarily unital) $ϕ_1$ and $ϕ_2$ which give a decomposition o
Alessia Cattabriga
In this paper we investigate the Alexander polynomial of (1,1)-knots, which are knots lying in a 3-manifold with genus one at most, admitting a particular decomposition. More precisely, we study the connections between the Alexander polynomial and a polynomial associated to a cyclic presentation of the fundamental group of an n-fold strongly-cyclic covering
Piotr Sniady
The convolution of indicators of two conjugacy classes on the symmetric group S_q is usually a complicated linear combination of indicators of many conjugacy classes. Similarly, a product of the moments of the Jucys--Murphy element involves many conjugacy classes with complicated coefficients. In this article we consider a combinatorial setup which allows us
Calin Chindris
We give necessary and sufficient inequalities for the existence of long exact sequences of m finite abelian p-groups with fixed isomorphy types. This problem is related to some generalized Littlewood-Richardson coefficients that we define in this paper. We also show how this problem is related to eigenvalues of Hermitian matrices satisfying certain (in)equal
Klaus Altmann, Juergen Hausen
We provide a complete description of normal affine varieties with effective algebraic torus action in terms of what we call proper polyhedral divisors on semiprojective varieties. Our theory extends classical cone constructions of Dolgachev, Demazure and Pinkham to the multigraded case, and it comprises the theory of affine toric varieties.
Yuri G. Zarhin
In his previous papers (J. reine angew. Math. 544 (2002), 91--110; math.AG/0103203) the author introduced a certain explicit construction of superelliptic jacobians, whose endomorphism ring is the ring of integers in the $p$th cyclotomic field. (Here $p$ is an odd prime.) In the present paper we discuss when these jacobians are mutually non-isogenous. (The c
Frank Meyer
This is an introduction to an algebraic construction of a gravity theory on noncommutative spaces which is based on a deformed algebra of (infinitesimal) diffeomorphisms. We start with some fundamental ideas and concepts of noncommutative spaces. Then the $θ$-deformation of diffeomorphisms is studied and a tensor calculus is defined. A deformed Einstein-Hilb
S. T. Love
Simultaneous nonlinear realizations of spontaneously broken supersymmetry in conjunction with other spontaneous and/or explicitly broken symmetries including R symmetry, global chiral symmetry, dilatations and the superconformal symmetries is reviewed.
J. A. Nieto
We considered the possibility that the oriented matroid theory is connected with supersymmetry via the Grassmann-Plucker relations. The main reason for this, is that such relations arise in both in the chirotopes definition of an oriented matroid, and in maximally supersymmetric solutions of eleven- and ten-dimensional supergravity theories. Taking this obse
Minoru Omote, Susumu kamefuchi
In the state-vector space for relativistic quantum fields a new set of basis vectors are introduced, which are taken to be eigenstates of the field operators themselves. The corresponding eigenvalues are then interpreted as representing matter waves associated with the respective quantum fields. The representation, based on such basis vectors, or the wave-re
Christopher T. Hill
Murray Gell-Mann, after co-inventing QCD, recognized the interplay of the scale anomaly, the renormalization group, and the origin of the strong scale, Lambda_{QCD}. I tell a story, then elaborate this concept, and for the sake of discussion, propose a conjecture that the physical world is scale invariant in the classical, \hbar -> 0, limit. This principle h
Shyamoli Chaudhuri
We derive the free energies of both the closed heterotic, and the unoriented, open and closed, type I string ensembles, consistent with the thermal (Euclidean T-duality) transformations on the String/M Duality Web. A crucial role is played by a temperature dependent Wilson line wrapping Euclidean time, responsible for the spontaneous breaking of supersymmetr
Mu-Chun Chen, K. T. Mahanthappa
We have constructed a SUSY SO(10) x SU(2)_F model in which a set of symmetric mass matrices with five texture zeros (having 11 parameters) leads to 22 measurable fermion masses, mixing angles and CP phases, all in agreement with available experimental data within one sigma. The LMA solution for solar neutrinos is obtained as well as neutrino mixing angles an
D. Kotlorz, A. Kotlorz
We solve the LO DGLAP QCD evolution equation for truncated Mellin moments of the nucleon nonsinglet structure function. The results are compared with those, obtained in the Chebyshev-polynomial approach for $x$-space solutions. Computations are performed for a wide range of the truncation point $10^{-5}\leq x_0\leq 0.9$ and $1\leq Q^2\leq 100 {\rm GeV}^2$. T
A. W. Thomas, R. D. Young
We explore further the idea that the lattice QCD data for hadron properties in the region m_π^2 > 0.2 GeV^2 can be described by the constituent quark model. This leads to a natural explanation of the fact that nucleon excited states are generally stable for pion masses greater than their physical excitation energies. Finally we apply these same ideas to the
J. -M. Gerard, F. Goffinet, M. Herquet
New data from neutrino oscillation experiments motivate us to extend a successful mass relation for the charged leptons to the other fundamental fermions. This new universal relation requires a Dirac mass around 3 10^-2 eV for the lightest neutrino and rules out a maximal atmospheric mixing. It also suggests a specific decomposition of the CKM mixing matrix.
Radiative return via electron pair production: Monte Carlo simulation of the process e+ e- --> pi+ pi- e+ e-
hep-phHenryk Czyz, Elzbieta Nowak-Kubat
Contributions from the reaction e+e- --> pi+pi- e+e- to the pion form factor measurement via radiative return method are discussed basing on the results of a Monte Carlo generator (EKHARA). The generator contains contributions from the initial and final state emission of a e+e- pair from e+e- --> pi+pi- production diagrams and the pi+pi- pair production from
Fan Wang, Wei-Min Sun, Xiao-Fu Lü
The conflict between cononical commutation relation and gauge invariance, which both the momentum and angular momentum of quark and gluon should satisfy, is clarified. The quantum version of gauge invariance is studied. The gauge independence of the matrix elements of quark momentum and angular momentum operators between physical states are proved. We sugges
N. Armesto, M. Cacciari, A. Dainese, C. A. Salgado
The ratio of nuclear modification factors of high-$p_T$ heavy-flavored mesons tolight-flavored hadrons (heavy-to-light ratio) is shown to be a sensitive tool to test medium-induced energy loss at RHIC and LHC energies. Heavy-to-light ratios of $D$ mesons at RHIC in the region $7<p_T<12$ GeV, and of $D$ and $B$ mesons at the LHC in the region $10<p_T<20$ GeV,
J. Cleymans, H. Oeschler, K. Redlich, S. Wheaton
The present status of the thermal model is reviewed and the recently discovered sharp peak in the $K^+/π^+$ ratio is discussed in this framework. It is shown that the rapid change is related to a transition from a baryon dominated hadronic gas to a meson dominated one. Further experimental tests to clarify the nature of the transition are discussed. In the t
S. M. Troshin
We discuss the point that the processes with high transverse momenta could have a nonperturbative origin. This discussion is motivated by the fact that there are several experimental indications that such processes can originate from soft dynamics. The model combined with unitarity and impact parameter picture provides simple mechanism for the hadron product
Guido ALTARELLI
A concise introduction to the Standard Model of fundamental particle interactions is presented.
Gauge invariance of elementary particle processes taking place in presence of a background magnetic field
hep-phKaushik Bhattacharya
Elementary particle scatterings and decays in presence of a background magnetic field are very common in physics, specially after the observation that the core of the neutron stars can sustain a magnetic field of the order of $10^{13} {\rm G}$. The important point about these calculations is that they are done in a background of a gauge field and as a result
J. Bernabeu, J. Burguet-Castell, C. Espinoza, M. Lindroos
To complete the picture of neutrino oscillations two fundamental parameters need to be measured, theta13 and delta. The next generation of long baseline neutrino oscillation experiments -superbeams, betabeams and neutrino factories- indeed take aim at measuring them. Here we explore the physics reach of a new candidate: an electron-capture neutrino beam. Emp
O. Kaczmarek, F. Zantow
We present results on heavy quark free energies in 2-flavour QCD. The temperature dependence of the interaction between static quark anti-quark pairs will be analyzed in terms of temperature dependent screening radii, which give a first estimate on the medium modification of (heavy quark) bound states in the quark gluon plasma. Comparing those radii to the (
O. Kaczmarek, F. Zantow
We discuss the temperature dependence of the screening lengths in quenched and full QCD using the non-perturbative lattice approach. We analyze the temperature dependence of distances which are defined as moments of quark antiquark free energies. These distance scales are supposed to describe the geometric size of partonic clouds which screen static charges
Taegil Bae, Jongjeong Kim, Weonjong Lee
We investigate the effect of non-degenerate quarks on $B_K$. This effect is noticeably large for $B_K$ (significantly larger than statistical uncertainty). Hence, it is important to include this effect in order to determine $B_K$ with higher precision. We also observe that the quality of fitting for $B_K$ gets better when we include non-degenerate combinatio
Jongjeong Kim, Taegil Bae, Weonjong Lee
We present preliminary results of $B_K$ calculated using improved staggered fermions with the mixed action (valence quarks = HYP staggered fermions and sea quarks = AsqTad staggered fermions). We analyze the data based upon the prediction by Van de Water and Sharpe. A hint of consistency with the prediction is observed. We also present preliminary results of
S. A. Dazeley
The proposed Double Chooz theta 13 experiment is described. Double Chooz will be an optimized reactor disappearance experiment similar to the original CHOOZ. The optimization includes an increase in the signal to noise by increasing the target volume to twice the original CHOOZ, reducing singles background with a non-scintillating oil buffer region around th
Alexey Garmash
We report results on the Dalitz analysis of three-body charmless B+=>K+pi+pi-, B0=>K0pi+pi- and B+=>K+K+K- decays including searches for direct CP violation in the B+=>K+pi+pi- mode. Branching fractions for a number of quasi-two-body intermediate states are reported. We also observe evidence with 3.9 sigma significance for a large direct CP violation in B+-=
Lev M. Tomilchik, Vladimir V. Kudryashov
The maximal acceleration (MA) problem associated with the position-dependent rest mass concept is considered. New arguments in favor of the mass-dependent maximal acceleration (MDMA) are put forward. The hypothesis that there exists a maximal force with the numerical value equal to the inverse Einstein's gravitation constant is advanced. The Lagrangian a
Rosa M. V. Figueiredo, Valmir C. Barbosa, Nelson Maculan, Cid C. Souza
Many well-known combinatorial optimization problems can be stated over the set of acyclic orientations of an undirected graph. For example, acyclic orientations with certain diameter constraints are closely related to the optimal solutions of the vertex coloring and frequency assignment problems. In this paper we introduce a linear programming formulation of
Jamal Saboune, François Charpillet
The aim of our study is to detect balance disorders and a tendency towards the falls in the elderly, knowing gait parameters. In this paper we present a new tool for gait analysis based on markerless human motion capture, from camera feeds. The system introduced here, recovers the 3D positions of several key points of the human body while walking. Foreground
Jamal Saboune, François Charpillet
In this paper we present a new approach for marker less human motion capture from conventional camera feeds. The aim of our study is to recover 3D positions of key points of the body that can serve for gait analysis. Our approach is based on foreground segmentation, an articulated body model and particle filters. In order to be generic and simple no restrict
M. Czenko, H. Tran, J. Doumen, S. Etalle
Community decisions about access control in virtual communities are non-monotonic in nature. This means that they cannot be expressed in current, monotonic trust management languages such as the family of Role Based Trust Management languages (RT). To solve this problem we propose RT-, which adds a restricted form of negation to the standard RT language, thu
Leif W Hanlen, Alex J Grant
In this paper we consider the computation of channel capacity for ergodic multiple-input multiple-output channels with additive white Gaussian noise. Two scenarios are considered. Firstly, a time-varying channel is considered in which both the transmitter and the receiver have knowledge of the channel realization. The optimal transmission strategy is water-f
K. Lai, W. Pan, D. C. Tsui, S. Lyon
We report here a systematic study of the energy gaps at the odd-integer quantum Hall states $ν=3$ and 5 under tilted magnetic (B) fields in a high quality Si two-dimensional electron system. Out of the coincidence region, the valley splitting is independent of the in-plane B fields. However, the $ν=3$ valley gap differs by about a factor of 3 ($Δ_v\sim$ 0.4K
T. Jeong, A. Kyker, W. E. Pickett
We address the origin of the incipient magnetism in TiBe$_2$ through precise first principles calculations, which overestimate the ferromagnetic tendency and therefore require correction to account for spin fluctuations. TiBe$_2$ has sharp fine structure in its electronic density of states, with a van Hove singularity only 3 meV above the Fermi level. Simila
K. Yu. Guslienko, X. F. Han, D. J. Keavney, R. Divan
We report direct imaging by means of x-ray photoemission electron microscopy of the dynamics of magnetic vortices confined in micron-size circular Permalloy dots that are 30 nm thick. The vortex core positions oscillate on a 10-ns timescale in a self-induced magnetostatic potential well after the in-plane magnetic field is turned off. The measured oscillatio
W. Song, A. K. M. Newaz, J. K. Son, E. E. Mendez
We have found experimentally that the shot noise of the tunneling current $I$ through an undoped semiconductor superlattice is reduced with respect to the Poissonian noise value $2eI$, and that the noise approaches 1/3 of that value in superlattices whose quantum wells are strongly coupled. On the other hand, when the coupling is weak or when a strong electr
G. A. Levin, P. N. Barnes, Naoyuki Amemiya, Satoshi Kasai
We report the results of a magnetization losses study in experimental multifilament, multiply connected coated superconductors exposed to time-varying magnetic field. In these samples, the superconducting layer is divided into parallel stripes segregated by non-superconducting grooves. In order to facilitate the current sharing between the stripes and thus i
Chun-Gang Duan, Renat F. Sabirianov, Wai-Ning Mei, Sitaram S. Jaswal
Recent experimental results demonstrate that in thin films ferroelectricity persists down to film thickness of a few unit cells. This finding opens an avenue for novel electronic devices based on ultathin ferroelectrics, but also raises questions about factors controlling ferroelectricity and the nature of the ferroelectric state at the nanoscale. Here we re
J. F. Annett, M. Krawiec, B. L. Gyorffy
We have previously shown that a ferromagnet-superconductor heterostructure may possess a spontaneous current circulation parallel to the interface. This current is caused by Andreev bound states in the thin ferromagnetic layer, and can be fully spin-polarized. Here we investigate the total energy of the system in cases where the current either does or does n
Magnetic field effects and renormalization of the long-range Coulomb interaction in Carbon Nanotubes
cond-mat.str-elS. Bellucci, P. Onorato
We develop two theoretical approaches for dealing with the low-energy effects of the repulsive interaction in one-dimensional electron systems. Renormalization Group methods allow us to study the low-energy behavior of the unscreened interaction between currents of well-defined chirality in a strictly one-dimensional electron system. A dimensional regulariza