May 2005 arXiv papers — page 15

I. Devetak

Two quantum information processing protocols are said to be dual under resource reversal if the resources consumed (generated) in one protocol are generated (consumed) in the other. Previously known examples include the duality between entanglement concentration and dilution, and the duality between coherent versions of teleportation and super-dense coding.

Stephanie Wehner, Ronald de Wolf

We prove new lower bounds for locally decodable codes and private information retrieval. We show that a 2-query LDC encoding n-bit strings over an l-bit alphabet, where the decoder only uses b bits of each queried position of the codeword, needs code length m = exp(Omega(n/(2^b Sum_{i=0}^b {l choose i}))) Similarly, a 2-server PIR scheme with an n-bit databa

Michael Gudo

When echinoderms are conceptualized as hydraulic entities, the early evolution of this group can be presented in a scenario which describes how a bilateral ancestor (an enteropneust-like organism) gradually evolved into a pentaradial echinoderm. According to this scenario, the arms are outgrowths from the anterior/posterior body axis of the bilateral pterobr

Wenzhe Ma, Chao Tang, Luhua Lai

Trypsin and chymotrypsin are both serine proteases with high sequence and structural similarities, but with different substrate specificity. Previous experiments have demonstrated the critical role of the two loops outside the binding pocket in controlling the specificity of the two enzymes. To understand the mechanism of such a control of specificity by dis

Michael Gudo

The pentaradial organisation of echinoderms is postulated to have evolved as the result of the reorganisation of the internal U-shaped mesentery of the intestinal tract during inflation of the trunk of a pterobranch-like ancestor. Under this scenario, loops of the mesentery developed between five hydraulic bulges by three different mechanisms: (1) by the ear

Nils Blüthgen, Karsten Brand, Branka Čajavec, Maciej Swat

Increasingly used high throughput experimental techniques, like DNA or protein microarrays give as a result groups of interesting, e.g. differentially regulated genes which require further biological interpretation. With the systematic functional annotation provided by the Gene Ontology the information required to automate the interpretation task is now acce

Homer G. Ellis

A purely geometrical relativity theory results from a construction that produces from three-dimensional space a happy unification of Kaluza's five-dimensional theory and Weyl's conformal theory. The theory can provide geometrical explanations for the following observed phenomena, among others: (a) lifetimes of elementary particles of lengths inversel

Ernesto Estrada, Juan A. Rodriguez-Velazquez

The representation of complex systems as networks is inappropriate for the study of certain problems. We show several examples of social, biological, ecological and technological systems where the use of complex networks gives very limited information about the structure of the system. We propose to use hypergraphs to represent these systems by introducing t

Janusz Miskiewicz, Marcel Ausloos

Different distance matrices are defined and applied to look for correlations between the gross domestic product of G7 countries. Results are illustrated through displays obtained from various graph methods. Significant similarities between results are obtained. A procedure for choosing the best distance function is proposed taking into account the size of th

A. N. Gorban, G. S. Yablonsky

Everything that is not prohibited is permissible. So, what is prohibited in the course of chemical reactions, heat transfer and other dissipative processes? Is it possible to "overshoot" the equilibrium, and if yes, then how far? Thermodynamically allowed and prohibited trajectories of processes are discussed by the example of effects of equilibrium

Roberto B. Salgado

We present a new visualization of the proper-time elapsed along an observer's worldline. By supplementing worldlines with light clocks, the measurement of space-time intervals is reduced to the "counting of ticks." The resulting space-time diagrams are pedagogically attractive because they emphasize the relativistic view that "time is what is

Alessandro Dell'Aquila, Paolo M. Ruti, Alfonso Sutera

In this work, we study the mean tropopause structure from the NCEP-NCAR reanalysis in the framework of a theory of baroclinic adjustment, focusing on the impact of baroclinic eddies on the mean tropopause height. In order to measure the effects of such perturbations, we introduce an appropriate global index that selects events of high baroclinic activity and

Antonia Ruiz, Eric J. Heller

The concept of quasiresonance was introduced in connection with inelastic collisions between one atom and a vibro-rotationally excited diatomic molecule. In its original form, the collisions induce {\sl quasiresonant} transfer of energy between the internal degrees of freedom of the diatom: there is a surprisingly accurate low order rational value for the ra

Marko T. Cvitas, Pavel Soldan, Jeremy M. Hutson

The long-range forces that act between three atoms are analysed in both atom-diatom and atom-atom-atom representations. Expressions for atom-diatom dispersion coefficients are obtained in terms of 3-body nonadditive coefficients. The anisotropy of atom-diatom C_6 dispersion coefficients arises primarily from nonadditive triple-dipole and quadruple-dipole for

Bernhard Rothenstein, Aldo De Sabata

We show that invariance of the electric charge and relativistic kinematics lead to the transformation equations for electric field intensity and the magnetic induction.

Claude M. Dion, Arne Keller, Osman Atabek

Efficient and long-lived field-free molecular orientation is achieved using only two kicks appropriately delayed in time. The understanding of the mechanism rests upon a molecular target state providing the best efficiency versus persistence compromise. An optimal control scheme is referred to for fixing the free parameters (amplitudes and the time delay bet

Guanghua Xu, Ed V. Hungerford, Larry Pinsky

We study twist expansions for parton fragmentation functions based on the definition of the twist as an invariant matrix element of a light-cone, bilocal operator. The results are then applied to a method which might be used to extract higher twist effects in the fragmentation sector using both $e^+ e^-$, and $e^- p$ collisions. We discuss how to apply the l

Ralf Averbeck

Experimental results on heavy-quark production in proton-proton, deuteron-gold, and gold-gold collisions at sqrt(s_(NN)) = 200 GeV at the Relativistic Heavy Ion Collider (RHIC) are reviewed.

Mark W. Coffey

We substantially apply the Li criterion for the Riemann hypothesis to hold. Based upon a series representation for the sequence \{λ_k\}, which are certain logarithmic derivatives of the Riemann xi function evaluated at unity, we determine new bounds for relevant Riemann zeta function sums and the sequence itself. We find that the Riemann hypothesis holds if

Mark W. Coffey

We consider summations over digamma and polygamma functions, often with summands of the form (\pm 1)^nψ(n+p/q)/n^r and (\pm 1)^nψ^{(m)} (n+p/q)/n^r, where m, p, q, and r are positive integers. We develop novel general integral representations and present explicit examples. Special cases of the sums reduce to known linear Euler sums. The sums of interest find

Yuri G. Kondratiev, Tobias Kuna, Maria Joao Oliveira

Combinatorial harmonic analysis techniques are used to develop new functional analysis methods based on Bogoliubov functionals. Concrete applications of the methods are presented, namely, the study of a non-equilibrium stochastic dynamics of continuous systems.

L. Godinho, M. E. Sousa-Dias

We address the problem of computing the fundamental group of a symplectic $S^1$-manifold for non-Hamiltonian actions on compact manifolds, and for Hamiltonian actions on non-compact manifolds with a proper moment map. We generalize known results for compact manifolds equipped with a Hamiltonian $S^1$-action. Several examples are presented to illustrate our m

David R. Bickel, Rudolf Fruehwirth

Advances in computing power enable more widespread use of the mode, which is a natural measure of central tendency since, as the most probable value, it is not influenced by the tails in the distribution. The properties of the half-sample mode, which is a simple and fast estimator of the mode of a continuous distribution, are studied. The half-sample mode is

Prosenjit Bose, Vida Dujmovic, David R. Wood

We prove that for all $0\leq t\leq k$ and $d\geq 2k$, every graph $G$ with treewidth at most $k$ has a `large' induced subgraph $H$, where $H$ has treewidth at most $t$ and every vertex in $H$ has degree at most $d$ in $G$. The order of $H$ depends on $t$, $k$, $d$, and the order of $G$. With $t=k$, we obtain large sets of bounded degree vertices. With $

Hirokazu Nasu

Let $Hilb P^3$ denote the Hilbert scheme of smooth connected curves in $P^3$. We consider maximal irreducible closed subsets $W \subset Hilb P^3$ whose general member $C$ is contained in a smooth cubic surface and investigate the conditions for $W$ to be a component of $(Hilb P^3)_{red}$. We especially study the case where the dimension of the tangent space

Dmitry Rokhlin, Walter Schachermayer

For a given element $f\in L^1$ and a convex cone $C\subset L^\infty$, $C\cap L^\infty_+=\{0\}$ we give necessary and sufficient conditions for the existence of an element $g\ge f$ lying in the polar of $C$. This polar is taken in $(L^\infty)^*$ and in $L^1$. In the context of mathematical finance the main result concerns the existence of martingale measures,

Sascha Orlik

In this paper we consider period domains over local fields for quasi-split reductive groups. We compute the continuous l-adic cohomology with compact support of them in the case of a basic isocrystal. This paper is a continuation of [O2] where we considered the etale cohomology with torsion coefficients of these spaces.

Erwann Aubry

We show that a complete Riemannian manifold of dimension $n$ with $\Ric\geq n{-}1$ and its $n$-st eigenvalue close to $n$ is both Gromov-Hausdorff close and diffeomorphic to the standard sphere. This extends, in an optimal way, a result of P. Petersen. We also show that a manifold with $\Ric\geq n{-}1$ and volume close to $\frac{\Vol\sn}{#π_1(M)}$ is both Gr

Anton Deitmar

Lefschetz formulae for torus actions on p-adic groups are proven.

A. E. Rosaev

A system of N points, each having mass m, and a central mass M forming a planar central configuration, is considered. The equations of motion of a test particle are given and compared using different coordinates. For large values of N, even or odd, the equations are given too. The method used for the computation of some relevant sums can be important for pra

Terence Tao

In this expository article, we describe the recent approach, motivated by ergodic theory, towards detecting arithmetic patterns in the primes, and in particular establishing that the primes contain arbitrarily long arithmetic progressions. One of the driving philosophies is to identify precisely what the obstructions could be that prevent the primes (or any

Adela N. Comanici

We consider a small SO(2)-equivariant perturbation of a reaction-diffusion system on the sphere, which is equivariant with respect to the group SO(3) of all rigid rotations. We consider a normally hyperbolic SO(3)-group orbit of a rotating wave on the sphere that persists to a normally hyperbolic SO(2)-invariant manifold $M(ε)$. We investigate the effects of

Matti Jutila, Yoichi Motohashi

Our principal aim in the present article is to establish a uniform hybrid bound for individual values on the critical line of Hecke $L$-functions associated with cusp forms over the full modular group. This is rendered in the statement that for $t\ge0$ $$ \eqalignno{H_j(\txt{1\over2}+it)&\ll(κ_j+t)^{1/3+ε},& (1.1)\cr H_{j,k}(\txt{1\over2}+it)&\ll (k+t)^{1/3+

Andriy Panasyuk

We give a criterion of (micro-)kroneckerity of the linear Poisson pencil on $\frak{g}^*$ related to an algebraic Nijenhuis operator $N:\frak{g}\to \frak{g}$ on a finite-dimensional Lie algebra $\frak{g}$. As an application we get a series of examples of completely integrable systems on semisimple Lie algebras related to Borel subalgebras and a new proof of t

M. Fernandez-Lebron, L. Narvaez-Macarro

Let k be a perfect field of positive characteristic, k(t)_{per} the perfect closure of k(t) and A=k[[X_1,...,X_n]]. We show that for any maximal ideal N of A'=k(t)_{per}\otimes_k A, the elements in \hat{A'_N} which are annihilated by the "Taylor" Hasse-Schmidt derivations with respect to the X_i form a coefficient field of \hat{A'_N}.

Michael Entov, Leonid Polterovich

We establish a link between symplectic topology and a recently emerged branch of functional analysis called the theory of quasi-states and quasi-measures. In the symplectic context quasi-states can be viewed as an algebraic way of packaging certain information contained in Floer theory, and in particular in spectral invariants of Hamiltonian diffeomorphisms

A. Rod Gover, Lawrence J. Peterson

The (Fefferman-Graham) ambient obstruction tensor is a conformally invariant symmetric trace-free 2-tensor on even-dimensional Riemannian and pseudo-Riemannian manifolds. The conformal deformation complex is a differential complex related to infinitesimal deformations of conformal structure. We construct a conformally invariant differential operator on algeb

O. A. Gelfond, M. A. Vasiliev

We study various $Sp(2M)$ invariant field equations corresponding to rank $r$ tensor products of the Fock (singleton) representation of $Sp(2M)$. These equations are shown to describe localization on ``branes'' of different dimensions embedded into the generalized space-time $\M_M$ with matrix (i.e., ``central charge'') coordinates. The case

G. Couture, C. Hamzaoui, A. M. Lussier

We study the impact of the positivity of the measure of CP violation in neutrino oscillations on the values of |V_e3| and |V_mu1|. We use the available information on the solar and atmospheric mixing parameters |V_e2| and |V_mu3| provided by neutrino oscillation data. We conclude that large values of |V_e3| are preferred at 95% confidence level. This, in tur

Andrzej J. Buras

After listing basic properties of the Standard Model (SM) that play the crucial role in the field of flavour and CP violation, we discuss the following topics: 1) CKM matrix and the unitarity triangle. 2) Theoretical framework in a non-technical manner, classifying various extentions of the SM. 3) Particle-Antiparticle mixing and various types of CP violatio

Ambar Ghosal, Debasish Majumdar

We demonstrate that `Bimaximal + Democratic' type neutrino mass matrix can accommodate the deviation of $θ_\odot$ from its maximal value which referred in the literature as `quark-lepton complementarity' along with the other present day neutrino experimental results, namely, atmospheric, CHOOZ, neutrinoless double beta decay ($ββ_{0ν}$) and result ob

Matteo Beccaria, Edoardo Mirabella

Electroweak radiative corrections can be evaluated in the Sudakov approximation, a systematic high energy expansion known to be relevant for the analysis of future collider experiments in the TeV energy range. In the Minimal Supersymmetric Standard Model and at next-to-leading order, Sudakov electroweak corrections satisfy remarkable relations at the one loo

Douglas Bryman, Andrzej J. Buras, Gino Isidori, Laurence Littenberg

We summarize the theoretical virtues of the rare K -> pi nu nu-bar decays and emphasize the unique role of KL -> pi0 nu nu-bar in probing the nature of physics beyond the Standard Model, in particular concerning possible new sources of CP violation and flavor-symmetry breaking. A brief summary of the prospects for the measurement of the KL -> pi0 nu nu-bar r

R Baishya, R Rajkhowa, J K Sarma

In this paper the singlet and non-singlet hadron structure functions have been obtained by solving Dokshitzer-Gribov-Lipatov-Alterelli-Parisi (DGLAP) evolution equations in leading order (LO) at the small-x limit. Here we have used a Taylor Series expansion and then the method of characteristics to solve the evolution equation. We have also calculated t and

Paolo Ciafaloni

Energy-growing electroweak corrections in the Standard Model are potentially relevant for LHC physics, for Next generation of Linear Colliders (NLCs) and for ultrahigh energy cosmic rays. I present here the results of recent work in which electroweak evolution equations (the analogous of DGLAP equations in QCD) have been derived. The main features of these e

Yadong Yang, Hongjun Hao, Fang Su

We study the effects of a modest V+A admixture strength in $b\tou$ current in the decay $B \toρl ν$. We have shown that the decay rate, lepton forward-backward distribution asymmetry $A_{FB}$ and polarization ratio are sensitive to the admixture. Future experimental studies of the decay at BaBar and BELLE could clarify the chirality of $b\to u$ current and m

G. Rakness

Measurements are reported of the production of high energy pi-zero mesons from the STAR experiment in p+p and d+Au collisions at sqrt(s_NN)=200 GeV and <eta>=4.00 (d beam direction). The inclusive yield agrees with perturbative QCD calculations in p+p collisions, but is found to be reduced in d+Au collisions. The azimuthal correlations of the forward pi-zero

Tomasz Skwarnicki

Recent CLEO results on electromagnetic and hadronic transitions in charmonium and bottomonium systems are reviewed.

Duncan A Brown

The INSPIRAL program is the LIGO Scientific Collaboration&#39;s computational engine for the search for gravitational waves from binary neutron stars and sub-solar mass black holes. We describe how this program, which makes use of the FINDCHIRP algorithm (discussed in a companion paper), is integrated into a sophisticated data analysis pipeline that was used

John G. Baker, James R. van Meter

Full interpretation of data from gravitational wave observations will require accurate numerical simulations of source systems, particularly binary black hole mergers. A leading approach to improving accuracy in numerical relativity simulations of black hole systems is through fixed or adaptive mesh refinement techniques. We describe a manifestation of numer

Manuel Arturo Izquierdo

With the goal of bringing to reseachers of the ancient andean khipus with a tool to share and process electronically the current corpus of these ancient information devices, I present on this paper a proposal for a Quipu Description Format (QDF), a XML based file format designed to describe such documents in a systematic and computer standard way.

Evan P. Greenberg, David R. Cheriton

Spam costs US corporations upwards of $8.9 billion a year, and comprises as much as 40% of all email received. Solutions exist to reduce the amount of spam seen by end users, but cannot withstand sophisticated attacks. Worse yet, many will occasionally misclassify and silently drop legitimate email. Spammers take advantage of the near-zero cost of sending em

Allison Ferguson, Bulbul Chakraborty

We study the appearance of large-scale dynamical heterogeneities in a simplified model of a driven, dissipative granular system. Simulations of steady-state gravity-driven flows of inelastically colliding hard disks show the formation of large-scale linear structures of particles with a high collision frequency. These chains can be shown to carry much of the

P. Badica, V. Sandu, G. Aldica, A. Iyo

Addition of (LiF)$_{y<0.15}$, and of proper amount of (AgO)$_{z=0.45-0.8}$ as oxidizing agent, to (Cu,C)Ba$_{2}$Ca$_{3}$Cu$_{4}$O$_{10+d}$ superconductor is useful to control and shift the doping characteristics (hole density and distribution, and level of disorder) into the region where the irreversible properties, i.e. fish-tail effect (FTE) and irreversib

Serge M. Nakhmanson, K. M. Rabe, David Vanderbilt

Composition-dependent structural and polar properties of epitaxial short-period CaTiO_3/SrTiO_3/BaTiO_3 superlattices grown on a SrTiO_3 substrate are investigated with first-principles density-functional theory computational techniques. Polarization enhancement with respect to bulk tetragonal BaTiO_3 is found for two- and three-component superlattices with

R. Pietri, C. R. Rotundu, B. Andraka, B. C. Daniels

The specific heat of polycrystalline Ce0.6La0.4Pb3 has been measured in magnetic fields ranging from 0 to 14 T. After subtraction of a lattice contribution, the specific heat between 1 K and 10 K is well described by the S=1/2 single-impurity Kondo model with just one adjustable parameter: the zero-field Kondo temperature. In particular, the variation in the

L. H. Willems van Beveren, R. Hanson, I. T. Vink, F. H. L. Koppens

We study the spin filling of a semiconductor quantum dot using excited-state spectroscopy in a strong magnetic field. The field is oriented in the plane of the two-dimensional electron gas in which the dot is electrostatically defined. By combining the observation of Zeeman splitting with our knowledge of the absolute number of electrons, we are able to dete

M. K. Kneip, D. R. Yakovlev, M. Bayer, A. A. Maksimov

The dynamics of spin-lattice relaxation of the Mn-ions in (Zn,Mn)Se-based diluted-magnetic-semiconductor quantum wells is studied by time-resolved photoluminescence. The spin-lattice relaxation time varies by five orders of magnitude from 10-3 down to 10-8 s, when the Mn content increases from 0.4 up to 11%. Free carriers play an important role in this dynam

Vivien Lecomte, Cecile Appert-Rolland, Frederic van Wijland

We present a general approach for computing the dynamic partition function of a continuous-time Markov process. The Ruelle topological pressure is identified with the large deviation function of a physical observable. We construct for the first time a corresponding finite Kolmogorov-Sinai entropy for these processes. Then, as an example, the latter is comput

Florin Radu, Alexei Nefedov, Johannes Grabis, Gregor Nowak

We have used soft X-ray Resonant Magnetic Scattering (XRMS) to search for the presence of an effective ferromagnetic moment belonging to the antiferromagnetic (AF) layer which is in close contact with a ferromagnetic (F) layer. Taking advantage of the element specificity of the XRMS technique, we have measured hysteresis loops of both Fe and CoO layers of a

Björn Samuelsson, Carl Troein

Despite their apparent simplicity, random Boolean networks display a rich variety of dynamical behaviors. Much work has been focused on the properties and abundance of attractors. The topologies of random Boolean networks with one input per node can be seen as graphs of random maps. We introduce an approach to investigating random maps and finding analytical

Akira Endo, Yasuhiro Iye

Detailed analysis of the commensurability oscillation (CO) has been performed on unidirectional lateral superlattices with periods ranging from a=92 to 184 nm. Fourier analysis reveals the second (and the third) harmonics along with the fundamental oscillation for a>=138 nm (184 nm) at low-enough temperature, evincing the presence of corresponding harmonics

C. Pennetta, E. Alfinito, L. Reggiani, S. Ruffo

We study the distribution of the resistance fluctuations of biased resistor networks in nonequilibrium steady states. The stationary conditions arise from the competition between two stochastic and biased processes of breaking and recovery of the elementary resistors. The fluctuations of the network resistance are calculated by Monte Carlo simulations which

A. Taldenkov, N. Babushkina, A. Inyushkin, O. Nikolaeva

We have investigated the effect of oxygen isotope substitution on the metal-insulator transition temperature and the resistivity of the narrow band manganite (La0.25Pr0.75)0.7Ca0.3MnO3 in a constant magnetic field. A set of 16 samples having different mixtures of 16O, 17O and 18O isotopes with average mass varying from 16.0 to 17.8 a.m.u. was studied. We hav

N. E. Sluchanko, A. V. Bogach, V. V. Glushkov, S. V. Demishev

Precision measurements of charge transport parameters (resistivity, Hall and Seebeck coefficients) have been carried out on high-quality single-crystals of cerium hexaboride in a wide temperature range 1.8-300 K. It is shown that in the temperature interval of 5 K < T < T* = 80 K the magnetic contribution in resistivity obeys the power law rm = T -1/n, which

V. T. Renard, I. V. Gornyi, O. A. Tkachenko, V. A. Tkachenko

We report an experimental study of quantum conductivity corrections in a low mobility, high density two-dimensional electron gas in a AlGaAs/GaAs/AlGaAs quantum well in a wide temperature range (1.5K - 110K). This temperature range covers both the diffusive and the ballistic interaction regimes for our samples. It has been therefore possible to study the cro

Naoyuki Tateiwa, Yoshinori Haga, Tatsuma D. Matsuda, Shugo Ikeda

The pressure dependences of the antiferromagnetic and superconducting transition temperatures have been investigated by ac heat capacity measurement under high pressures for the heavy-fermion superconductor CePt$_3$Si without inversion symmetry in the tetragonal structure. The Néel temperature $T_{\rm N}$ = 2.2 K decreases with increasing pressure and become

K. Miyake, H. Kohno

It is shown that the quasi-universal ratio $q=\lim_{T\to0}eS/C\sim\pm1$ of the Seebeck coefficient to the specific heat in the limit of T=0 observed in a series of strongly correlated metals can be understood on the basis of the Fermi liquid theory description. In deriving this result, it is crucial that a relevant scattering arises from impurities, but not

Jai Singh, Anchal Srivastava, R. S. Tiwari, O. N. Srivastava

This paper deals with the investigations on the nucleation and growth of ZnO nanostructures in a catalyst free synthesis. The ZnO nanostructures have been formed by evaporation of Zn (99.99%) in O_2 and Ar atmosphere in single zone furnace under two temperature regions, region A (~1173-1073K) and region B (~873-773K). Through application of XRD and TEM techn

H. Bahlouli, A. D. Alhaidari, A. Al-Zahrani, E. N. Economou

We study the massless limit of the Klein-Gordon (K-G) equation in 1+1 dimensions with static complex potentials as an attempt to give an alternative, but equivalent, representation of plane electromagnetic (em) wave propagation in active medium. In the case of dispersionless em medium, the analogy dictates that the potential in the K-G equation is complex an

Kazumasa Hattori, Satoshi Yotsuhashi, Kazumasa Miyake

The aspect of the quasiparticle interaction of a local Fermi liquid, the impurity version of f$^2$-based heavy fermions, is studied by the Wilson numerical renormalization group method. In particular, the case of the f$^2$-singlet crystalline-electric-field ground state is investigated assuming the case of UPt$_3$ with the hexagonal symmetry. It is found tha

Shidong Wang, Milena Grifoni

We analytically demonstrate helicity determined selection rules for intershell tunneling in double-walled nanotubes with commensurate (c-DWNTs) and incommensurate (i-DWNTs) shells. For i-DWNTs the coupling is negligible between lowest energy subbands, but it becomes important as the higher subbands become populated. In turn the elastic mean free path of i-DW

P. Limelette, V. Hardy, P. Auban-Senzier, D. Jerome

We have performed both in-plane resistivity, Hall effect and specific heat measurements on the thermoelectric cobalt oxide Ca$_{3}$Co$_{4}$O$_{9}$. Four distinct transport regimes are found as a function of temperature, corresponding to a low temperature insulating one up to $T_{min}\approx $63 K, a strongly correlated Fermi liquid up to $T^*\approx $140 K,

Yogesh Singh, R. Nirmala, S. Ramakrishnan, S. K. Malik

We have performed bulk measurements such as dc magnetic susceptibility, electrical resistivity and heat capacity on the pseudo-ternary alloys Lu$_5$Ir$_4$(Si$_{1-x}$Ge$_x$)$_{10}$ to study the interplay and competition between superconductivity and the charge density wave (CDW) ordering transition. We track the evolution of the superconducting transition tem

A. B. Mutiara

Based on Sjögren und Sjolander&#39;s Mode-Coupling(MC)-Model, we have reformulated and calculated the memory kernel (MK) of the velocity autocorrelation function (VACF)on a Ni$_{0.2}$Zr$_{0.8}$-liquid. Reformulating means here that we have constructed the memory kernel of VACF for our binary system, instead of one for one atomic system of the Sjögren und Sjo

R. B. Saxena, Rajiv Giri, V. P. S. Awana, H. K. Singh

Samples of series Bi1.6Pb0.4Sr2Ca2Cu3-xZnxO10 with x = 0.0, 0.015, 0.03, 0.06, 0.09 and 0.12 are synthesized by solid-state reaction route. All the samples crystallize in tetragonal structure with majority (> 90%) of Bi-2223 (Bi2Sr2Ca2Cu3O10) phase (c-lattice parameter ~ 36 A0). The proportion of Bi-2223 phase decreases slightly with an increase in x. The la

Masanori Ichioka, Yasushi Matsunaga, Kazushige Machida

A simulation study for the magnetization process is performed for the multi-domain state in a chiral p-wave superconductor, using the time-dependent Ginzburg-Landau theory. The external field penetrates inside as core-less vortices through the domain wall, forming the vortex sheet structure. We find that, with increasing magnetic fields, the domain walls mov

A. G. Slivka, V. M. Kedyulich, R. R. Levitskii, A. P. Moina

The present work contains results of experimental investigation of external factors, such as dessicating/wetting, thermal annealing, uniaxial and hydrostatic pressures on dielectric permittivity of Rochelle salt crystals. The obtained results are compared with available literature data. A conslusion is made that the dispersion of experimental data can be att

David Aldous

In a network where the cost of flow across an edge is nonlinear in the volume of flow, and where sources and destinations are uniform, one can consider the relationship between total volume $v$ of flow through the network and the minimum cost $c = Psi(v)$ of any flow with volume $v$. Under a simple probability model (locally tree-like directed network, indep

S. M. A. Rombouts, L. Pollet, K. Van Houcke

The bosonic atoms used in present day experiments on Bose-Einstein condensation are made up of fermionic electrons and nucleons. In this Letter we demonstrate how the Pauli exclusion principle for these constituents puts an upper limit on the Bose-Einstein-condensed fraction. Detailed numerical results are presented for hydrogen atoms in a cubic volume and f

I. Vragović, E. Louis, C. D. E. Boschi, G. J. Ortega

The question of how network topology influences emergent synchronized oscillations in excitable media is addressed. Coupled van der Pol-FitzHugh-Nagumo elements arranged either on regular rings or on clusters of the square lattice are investigated. Clustered and declustered rings are constructed to have the same number of next-nearest-neighbors (four) and a

Natalya A. Zimbovskaya, Godfrey Gumbs, Joseph L. Birman

A quasiclassical theory for dc magnetotransport in a modulated quantum Hall system near filling factor $ν={1/2}$ is presented. A weak one-dimensional electrostatic potential acts on the two-dimensional electron gas. Closed form analytic expressions are obtained for the resistivity $ρ_\perp$ corresponding to a current at right angles to the direction of the m

J. C. Lattanzio, M. A. Lugaro

AGB stars are the source for the main component of the $s$-process. Here we discuss both the properties which are reasonably well known and those which still suffer from substantial uncertainties. In the former case, we are fairly sure that the $s$-process contribution from AGB stars comes from masses between about 1 and 3 $\msun$, and the dominant neutron s

A. Finoguenov, H. Boehringer, J. P. F. Osmond, T. J. Ponman

We put together the results of XMM-Newton observations of a number of representative group and cluster samples at low and high redshifts. These results confirm the entropy ramp as an explanation of the observed scaling relations. We observe a mild evolution in the entropy of clusters. The observed degree of evolution is consistent with expectations of the sh

A. M. Hopkins, S. M. Rao, D. A. Turnshek

The local power law relationship between the surface densities of neutral hydrogen gas and star formation rate (SFR) can be used to explore the SFR properties of damped Lyman alpha (DLA) systems at higher redshift. We find that while the SFR densities for DLA systems are consistent with luminous star forming galaxies at redshifts below z~0.6, at higher redsh

E. F. Brown, A. C. Calder, T. Plewa, P. M. Ricker

We present our first nucleosynthesis results from a numerical simulation of the thermonuclear disruption of a static cold Chandrasekhar-mass C/O white dwarf. The two-dimensional simulation was performed with an adaptive-mesh Eulerian hydrodynamics code, FLASH, that uses as a flame capturing scheme the evolution of a passive scaler. To compute the isotopic yi

Stefan I. B. Cartledge, Geoffrey C. Clayton, Karl D. Gordon, Brian L. Rachford

We present an extinction analysis of 9 paths through the LMC and SMC based on FUSE observations. To date, just two LMC sight lines have probed dust grain composition and size distributions in the Clouds using spectra including wavelengths as short as 950 A. We supplement these with results from 4 regions distinguished by their IR through UV extinction curves

David A. Buote, Philip J. Humphrey, John T. Stocke

We present an analysis of a Chandra ACIS-I observation of the massive galaxy cluster A644. This cluster was previously classified as a cooling flow, but no radio emission has been detected from its cD galaxy. Outside the core (R ~75 kpc ~0.03R_vir) the hot ICM has properties consistent with a (relaxed) cool-core cluster out to the largest radii investigated

Francesc Ferrer

Ground based Atmospheric Cerenkov Telescopes have recently unveiled a TeV gamma-ray signal from the direction of the Galactic Centre. We examine whether these gamma-rays, observed by the VERITAS, CANGAROO-II and HESS collaborations, may arise from annihilations of dark matter particles. Emission from nearby dwarf spheroidals, such as Sagittarius, could provi

KASCADE Collaboration, T. Antoni

A composition analysis of KASCADE air shower data is performed by means of unfolding the two-dimensional frequency spectrum of electron and muon numbers. Aim of the analysis is the determination of energy spectra for elemental groups representing the chemical composition of primary cosmic rays. Since such an analysis depends crucially on simulations of air s

E. V. Bugaev

A review of the recent achievements in high energy neutrino physics and, partly, neutrino astrophysics is presented. It is argued that experiments with high energy neutrinos of natural origin can be used for a search of new physics effects beyond the electroweak scale.

M. Fellhauer, P. Kroupa

After the stars of a new, embedded star cluster have formed they blow the remaining gas out of the cluster. Especially winds of massive stars and definitely the on-set of the first supernovae can remove the residual gas from a cluster. This leads to a very violent mass-loss and leaves the cluster out of dynamical equilibrium. Standard models predict that wit

A. Joinet, E. Jourdain, J. Malzac, J. P. Roques

IGR J17464-3213, already known as the HEAO-1 transient source H1743-322, has been detected during a state transition by the SPI/INTEGRAL telescope. We describe the spectral evolution and flaring activity of IGR J17464-3213/H1743-322 from 2003 March 21 to 2003 April 22. During the first part, the source followed a continuous spectral softening, with the peak

Anil Bhardwaj, Ronald F. Elsner, J. Hunter Waite,, G. Randall Gladstone

Using the Advanced CCD Imaging Spectrometer (ACIS), the Chandra X-ray Observatory (CXO) observed the Saturnian system for one rotation of the planet (~37 ks) on 20 January, 2004, and again on 26-27 January, 2004. In this letter we report the detection of X-ray emission from the rings of Saturn. The X-ray spectrum from the rings is dominated by emission in a

R. P. Kraft, L. A. Nolan, T. J. Ponman, C. Jones

We present results from a 34 ks Chandra/ACIS-S observation of the nearby (d=3.1 Mpc) lenticular galaxy NGC 5102, previously shown to have an unusually low X-ray luminosity. We detect eleven X-ray point sources within the the $D_{25}$ optical boundary of the galaxy (93% of the light), one third to one half of which are likely to be background AGN. One source

L. Coccato, E. M. Corsini, A. Pizzella, F. Bertola

We present the minor-axis kinematics of ionized gas and stars for a sample of 5 spiral galaxies, which are characterized by either a zero or a shallow gas velocity gradient along their major axis. The asymmetric velocity profiles observed along the minor axis of NGC 4064 and NGC 4189 can be explained as due to the presence of a bar. This is also the case of

E. J. Barlow, A. J. Bird, D. J. Clark, R. Cornelisse

We present the transient nature of INTEGRAL source IGR J17285-2922, identified from a single period of activity during an IBIS/ISGRI Galactic Centre Deep Exposure in September 2003. The source has a maximum detection significance of 14 sigma in the 20-100 keV energy range and exhibits a flux of 6.5 mCrab before it moves out of the ISGRI field of view. The so

C. W. Ormel, R. F. Shipman, V. Ossenkopf, F. P. Helmich

This paper presents results from modelling 450 micron and 850 micron continuum and HCO+ line observations of three distinct cores of an infrared dark cloud (IRDC) directed toward the W51 GMC. In the sub-mm continuum these cores appear as bright, isolated emission features. One of them coincides with the peak of 8.3 micron extinction as measured by the Midcou

Ioana Dutan, Peter L. Biermann

We present a theoretical model for driving jets by accretion onto Kerr black holes and try to give an answer to the following question: How much energy could be extracted from a rotating black hole and its accretion disk in order to power relativistic jets in Active Galactic Nuclei?

Didier Barret, Jean-Francois Olive, M. Coleman Miller

Using archival data from the Rossi X-ray Timing Explorer (RXTE), we study in a systematic way the variation of the quality factor and amplitude of the lower and upper kHz quasi-periodic oscillations (QPO) in the low-mass X-ray binary 4U1636-536, over a frequency range from ~550 Hz to ~1200 Hz. When represented in a quality factor versus frequency diagram, th