October 2008 arXiv papers — page 55
Showing 5,401–5,500 of 5,765 papers
Maminirina Joelson, Marie Christine Neel
We propose a new formulation of the probability distribution function of wind driven water surface slope with an $α$-stable distribution probability. The mathematical formulation of the probability distribution function is given under an integral formulation. Application to represent the probability of time slope data from laboratory experiments is carried o
Tunnelling through a semiconducting spacer: complex band predictions vs. thin film calculations
cond-mat.mes-hallJ. Peralta-Ramos, J. Milano, A. M. Llois
Using a simple tight-binding model, we compare the limitations of the tunnelling predictions coming out of the complex band structure of a semiconductor with the output of thin film calculations done for the same semiconducting spacer but considering it to be of finite width, and sandwiched by metallic electrodes. The comparison is made as a function of spac
Gelu Popescu
The theory of characteristic functions for row contractions is used to determine the group $Aut(B(H)^n_1)$ of all free holomorphic automorphisms of the unit ball of $B(H)^n$. We show that the noncommutative Poisson transform commutes with the action of the automorphism group $Aut(B(H)^n_1)$. This leads to a characterization of the unitarily implemented autom
Diego Guadagnoli
After a short overview of the hypothesis of Yukawa unification within SUSY GUTs, I detail on the general conditions for its phenomenological viability, emphasizing the decisive role played by observables in the flavor sector.
I. Panneer Muthuselvam, R. N. Bhowmik
We report a correlation between structural phase stability and magnetic properties of Co2FeO4 spinel oxide. We employed mechanical alloying and subsequent annealing to obtain the desired samples. The particle size of the samples changes from 25 nm to 45 nm. The structural phase separation of samples, except sample annealed at 9000C, into Co rich and Fe rich
Francesco Cianfrani, Giovanni Montani
We find out classical particles, starting from Dirac quantum fields on a curved space-time, by an eikonal approximation and a localization hypothesis for amplitudes. We recover the results by Mathisson-Papapetrou, hence establishing a fundamental correspondence between the coupling of classical and quantum spinning particles with the gravitational field.
A near-IR variability study of the Galactic black hole: a red noise source with no detected periodicity
astro-phTuan Do, Andrea M. Ghez, Mark R. Morris, Sylvana Yelda
We present the results of near-infrared (2 and 3 microns) monitoring of Sgr A*-IR with 1 min time sampling using the natural and laser guide star adaptive optics (LGS AO) system at the Keck II telescope. Sgr A*-IR was observed continuously for up to three hours on each of seven nights, between 2005 July and 2007 August. Sgr A*-IR is detected at all times and
The Status and future of ground-based TeV gamma-ray astronomy. A White Paper prepared for the Division of Astrophysics of the American Physical Society
astro-phJ. Buckley, K. Byrum, B. Dingus, A. Falcone
In recent years, ground-based TeV gamma-ray observatories have made spectacular discoveries including imaging spectroscopy observations of galactic sources of different classes, and the discovery of rapid gamma-ray flares from radio galaxies and active galactic nuclei containing supermassive black holes. These discoveries, and the fact that gamma-ray astrono
Polynomial maps over $p$-adics and residual properties of mapping tori of group endomorphisms
math.GRAlexander Borisov, Mark Sapir
We continue our study of residual properties of mapping tori of free group endomorphisms. In this paper, we prove that each of these groups are virtually residually (finite $p$)-groups for all but finitely many primes$p$. The method involves further studies of polynomial maps over finite fields and $p$-adic completions of number fields.
H. -R. Müller, P. C. Frisch, B. D. Fields, G. P. Zank
Because of the dynamic nature of the interstellar medium, the Sun should have encountered a variety of different interstellar environments in its lifetime. As the solar wind interacts with the surrounding interstellar medium to form a heliosphere, different heliosphere shapes, sizes, and particle contents result from the different environments. Some of the l
Pilar Benito, Alberto Elduque, Fabián Martín-Herce
Lie-Yamaguti algebras (or generalized Lie triple systems) are binary-ternary algebras intimately related to reductive homogeneous spaces. The Lie-Yamaguti algebras which are irreducible as modules over their Lie inner derivation algebra are the algebraic counterpart of the isotropy irreducible homogeneous spaces. These systems will be shown to split into thr
R. N. Bhowmik, Nrisimha Murty. M, Sekhar Srinadhu. E
We have synthesized Cr1.4Fe0.6O3 compound through mechanical alloying of Cr2O3 and Fe2O3 powders and subsequent thermal annealing. The XRD spectrum, SEM picture and microanalysis of EDAX spectrum have been used to understand the structural evolution in the alloyed compound. The alloyed samples are matching to rhombohedral structure with R3C space group. The
B. R. Conrad, W. G. Cullen, D. B. Dougherty, I. Lyubinetsky
Spatial step edge fluctuations on a multi-component surface of Al/Si(111)-(root3 x root3) were measured via scanning tunneling microscopy over a temperature range of 720K-1070K, for step lengths of L = 65-160 nm. Even though the time scale of fluctuations of steps on this surface varies by orders of magnitude over the indicated temperature ranges, measured f
Timothy H. Boyer
It is shown that a nonrelativistic mechanical system involving a general nonrelativistic potential V(|r1-r2|) between point particles at positions r1 and r2 can be extended to a Lagrangian system which is invariant under Lorentz transformation through order v^2/c^2. However, this invariance requires the introduction of velocity-dependent and acceleration-dep
Variations in the dip properties of the low-mass X-ray binary XB 1254-69 observed with XMM-Newton and INTEGRAL
astro-phM. Diaz Trigo, A. N. Parmar, L. Boirin, C. Motch
We have analysed data from five XMM-Newton observations of XB 1254-69, one of them simultaneous with INTEGRAL, to investigate the mechanism responsible for the highly variable dips durations and depths seen from this low-mass X-ray binary. Deep dips were present during two observations, shallow dips during one and no dips were detected during the remaining t
Michael G. Endres
We present results from a lattice study of SU(2) color, N=1 supersymmetric Yang-Mills theory using domain wall fermions. Supersymmetry in this particular lattice formulation is expected to emerge in the continuum and chiral limits without any fine-tuning of operators. Preliminary results for the static quark potential, residual mass, chiral condensate and sp
Mechanism and Kinetics of Na+ Ion Depletion under the Anode during Electro-thermal Poling of a Bioactive Glass
cond-mat.mtrl-sciC. R. Mariappan, B. Roling
Electro-thermal poling experiments were carried out on a bioactive glass, and the kinetics of the Na+ ion depletion layer formation under the anode was studied in-situ by means of ac impedance spectroscopy. One important finding is a linear relation between the depletion layer thickness and the applied voltage, which is in contrast to the predictions of stan
Elba Gomar-Nadal, Brad R. Conrad, William G. Cullen, Ellen D. Willams
Pentacenequinone (PnQ) impurities have been introduced into a pentacene source material at number densities from 0.001 to 0.474 to quantify the relative effects of impurity content and grain boundary structure on transport in pentacene thin-film transistors. Atomic force microscopy (AFM) and electrical measurements of top-contact pentacene thin-film transist
D. M. Fenech, T. W. B. Muxlow, R. J. Beswick, A. Pedlar
The results of an extremely deep, 8-day long observation of the central kpc of the nearby starburst galaxy M82 using MERLIN (Multi-Element Radio Linked Interferometer Network) at 5 GHz are presented. The 17E-06 Jy/beam, rms noise level in the naturally weighted image make it the most sensitive high resolution radio image of M82 made to date. Over 50 discrete
S. Roth, C. Ciemniak, C. Coppi, F. v. Feilitzsch
Weakly Interacting Massive Particles (WIMPs) are candidates for non-baryonic Dark Matter. WIMPs are supposed to interact with baryonic matter via scattering off nuclei producing a nuclear recoil with energies up to a few 10 keV with a very low interaction rate of ~10^(-6) events per kg of target material and day in the energy region of interest. The Dark Mat
Ihor Lubashevsky, Namik Guseyn-zade, Cyril Garnisov, Boris Livshits
The 3D fundamental diagrams and phase portraits for tunnel traffic is constructed based on the empirical data collected during the last years in the deep long branch of the Lefortovo tunnel located on the 3rd circular highway in Moscow. This tunnel of length 3 km is equipped with a dense system of stationary ra-diodetetors distributed uniformly along it cheq
M. Bonesini
The international Muon Ionization Cooling Experiment (MICE) will carry out a systematic investigation of ionization cooling of a muon beam. As the emittance measurement will be done on a particle-by-particle basis, sophisticated beam instrumentation is needed to measure particle coordinates and timing vs RF. A PID system based on three time-of-flight station
Bound states and magnetic field-induced valley splitting in gate-tunable graphene quantum dots
cond-mat.mes-hallPatrik Recher, Johan Nilsson, Guido Burkard, Bjoern Trauzettel
The magnetic field dependence of energy levels in gapped single- and bilayer graphene quantum dots (QDs) defined by electrostatic gates is studied analytically in terms of the Dirac equation. Due to the absence of sharp edges in these types of QDs, the valley degree of freedom is a good quantum number. We show that its degeneracy is efficiently and controlla
S. Novotny, H. Rubinstein, H. Buhr, O. Novotný
On a dense energy grid reaching up to 75 meV electron collision energy the fragmentation angle and the kinetic energy release of neutral dissociative recombination fragments have been studied in a twin merged beam experiment. The anisotropy described by Legendre polynomials and the extracted rotational state contributions were found to vary on a likewise nar
Andrea P. Buccino, Pablo J. D. Mauas
We study the Mount Wilson indices we obtained indirectly from IUE high and low resolution spectra of the RS CVn-type systems II Peg (K2IV), UX Ari (K0IV+G5V) and V711 Tau (K1IV+G5V), extensively observed by IUE from 1978 to 1996. We analyze the activity signatures, which correspond to the primary star, with the Lomb-Scargle periodogram. From the analysis of
Joanna I. Sułkowska, Piotr Sułkowski, P. Szymczak, Marek Cieplak
Molecular dynamics studies within a coarse-grained structure based model were used on two similar proteins belonging to the transcarbamylase family to probe the effects in the native structure of a knot. The first protein, N-acetylornithine transcarbamylase, contains no knot whereas human ormithine transcarbamylase contains a trefoil knot located deep within
M. Bonesini
This paper is about the available hadroproduction data to be used for the tuning of neutrino beamline simulations, going from conventional neutrino beams to superbeams and neutrino factories. Comparisons of data with existing Monte Carlo computations will be shown. Recent results from the HARP experiment at CERN PS will be summarized, including data useful f
F. Castellano, R. C. Iotti, F. Rossi
A semiconductor-based terahertz-detector strategy, exploiting a bound-to-bound-to-continuum architecture, is presented and investigated. In particular, a ladder of equidistant energy levels is employed, whose step is tuned to the desired detection frequency and allows for sequential multi-photon absorption. Our theoretical analysis demonstrates that the prop
Thorsten Holm, Peter Jorgensen
Let D be a triangulated category with a cluster tilting subcategory U. The quotient category D/U is abelian; suppose that it has finite global dimension. We show that projection from D to D/U sends cluster tilting subcategories of D to support tilting subcategories of D/U, and that, in turn, support tilting subcategories of D/U can be lifted uniquely to maxi
Jonathan M. Butterworth, Adam R. Davison, Mathieu Rubin, Gavin P. Salam
We show that W H and Z H production where the Higgs boson decays to bbbar can be recovered as good search channels for the Standard Model Higgs at the Large Hadron Collider. This is done by requiring the Higgs to have high transverse momentum, and employing state-of-the-art jet reconstruction and decomposition techniques.
Martin Huarte-Espinosa, Martin Krause, Paul Alexander, Christian R. Kaiser
We investigate the effects of intermittent strong jets from an Active Galactic Nuclei (AGN) of a massive galaxy in the core of a cool core galaxy cluster, on the dynamics and metal distribution of the intra-cluster medium (ICM). We use a simple model for the metal distribution within the host galaxy which includes metal injection via star formation. We carry
Christian Huck
We address the problem of uniquely reconstructing F-type icosahedral quasicrystals from few images produced by quantitative high resolution transmission electron microscopy and explain recent results in the discrete tomography of these sets.
B. Gendre, A. Klotz, G. Stratta, B. Preger
We present the multi-wavelength study of those gamma-ray bursts observed by TAROT. These events are characterized by the presence at early time of a rising in their optical light curves lasting a few hundred of seconds. In one case (GRB 060904B), a flare occurs at similar time in the X-ray band, while in the other cases the X-ray light curves appear smooth d
A. Petrignani, H. Kreckel, M. H. Berg, S. Altevogt
The dissociative recombination of the lowest rotational states of H3+ has been investigated at the storage ring TSR using a cryogenic 22-pole radiofrequency ion trap as injector. The H3+ was cooled with buffer gas at ~15 K to the lowest rotational levels, (J,G)=(1,0) and (1,1), which belong to the ortho and para proton-spin symmetry, respectively. The rate c
J. P. Clancy, J. P. C. Ruff, S. R. Dunsiger, Y. Zhao
Elastic and inelastic neutron scattering studies have been carried out on the pyrochlore magnet Ho2Ti2O7. Measurements in zero applied magnetic field show that the disordered spin ice ground state of Ho2Ti2O7 is characterized by a pattern of rectangular diffuse elastic scattering within the [HHL] plane of reciprocal space, which closely resembles the zone bo
R. Wesson, M. J. Barlow, R. L. M. Corradi, J. E. Drew
Nova V458 Vul erupted on 2007 August 8th and reached a visual magnitude of 8.1 a few days later. H$α$ images obtained six weeks before the outburst as part of the IPHAS galactic plane survey reveal an 18th magnitude progenitor surrounded by an extended nebula. Subsequent images and spectroscopy of the nebula reveal an inner nebular knot increasing rapidly in
Martin R. Bridson
We consider finitely presented,residually finite groups $G$ and finitely generated normal subgroups $A$ such that the inclusion $A\hookrightarrow G$ induces an isomorphism from the profinite completion of $A$ to a direct factor of the profinite completion of $G$. We explain why $A$ need not be a direct factor of a subgroup of finite index in $G$; indeed $G$
Piotr M. Soltan
Answering a question of Shuzhou Wang we give a description of quantum $\SO(3)$ groups of Podleś as universal objects. We use this result to give a complete classification of all continuous compact quantum group actions on $M_2$.
S. Ciuchi, S. Fratini
We derive an effective cluster model to address the transport properties of mutually interacting small polarons. We propose a decoupling scheme where the hopping dynamics of any given particle is determined by separating out explicitly the degrees of freedom of its environment, which are treated as a statistical bath. The general cavity method developed here
Olivier Mathieu
Quickly convergent series are given to compute polyzeta numbers. The formula involves an intricate combination of (generalized) polylogarithms at 1/2. However, the combinatorics has a very simple geometric interpretation: it corresponds with the square map on some symmetric space P.
Peter Fulop, Benedek Kovacs, Sandor Imre
This paper investigates mobility management strategies from the point of view of their need of signalling and processing resources on the backbone network and load on the air interface. A method is proposed to model the serving network and mobile node mobility in order to be able to compare the different types of mobility management algorithms. To obtain a g
Direct Simulation of Low-Pressure Supersonic Gas Expansions and its Experimental Verification
physics.atom-phAlexander Nass, Erhard Steffens
The use of gas expansions to generate atomic or molecular beams has become a standard technique in nuclear and hadron physics for the production of polarized ion beams and gas targets. A direct simulation Monte Carlo method was used to understand the processes occurring in an expansion of highly dissociated hydrogen or deuterium gas at low densities. The res
Thibaut Paumard
The supermassive black hole candidate at the Galactic Center is surrounded by a parsec-scale star cluster, which contains a number of early type stars. The presence of such stars has been called a "paradox of youth" as star formation in the immediate vicinity of a supermassive black hole seemed difficult, as well as the transport of stars from far ou
Martin R. Bridson
We consider pairs of finitely presented, residually finite groups $P\hookrightarrow\G$ for which the induced map of profinite completions $\hat P\to \hat\G$ is an isomorphism. We prove that there is no algorithm that, given an arbitrary such pair, can determine whether or not $P$ is isomorphic to $\G$. We construct pairs for which the conjugacy problem in $\
Voltage controlled inversion of magnetic anisotropy in a ferromagnetic thin film at room temperature
cond-mat.mtrl-sciM. Weiler, A. Brandlmaier, S. Gepraegs, M. Althammer
The control of magnetic properties by means of an electric field is an important aspect in magnetism and magnetoelectronics. We here utilize magnetoelastic coupling in ferromagnetic/piezoelectric hybrids to realize a voltage control of magnetization orientation at room temperature. The samples consist of polycrystalline nickel thin films evaporated onto piez
Jordi Marzo, Joaquim Ortega-Cerdá
We prove upper pointwise estimates for the Bergman kernel of the weighted Fock space of entire functions in $L^2(e^{-2ϕ})$ where $ϕ$ is a subharmonic function with $Δϕ$ a doubling measure. We derive estimates for the canonical solution operator to the inhomogeneous Cauchy-Riemann equation and we characterize the compactness of this operator in terms of $Δϕ$.
Radio Astronomy Data Model for Single-Dish Multiple-Feed Telescopes, and Robledo Archive Architecture
astro-phJ. D. Santander-Vela, E. Garcia, J. F. Gomez, L. Verdes-Montenegro
All the effort that the astrophysical community has put into the development of the Virtual Observatory (VO) has surpassed the non-return point: the VO is a reality today, and an initiative that will self-sustain, and to which all archival projects must adhere. We have started the design of the scientific archive for the DSS-63 70-m antenna at NASA's DSN
L. B. L. Santos, M. C. Costa, S. T. R. Pinho, R. F. S. Andrade
The transmission of vector infectious diseases, which produces complex spatiotemporal patterns, is analyzed by a periodically forced two-dimensional cellular automata model. The system, which comprises three population levels, is introduced to describe complex features of the dynamics of the vector transmitted dengue epidemics, known to be very sensitive to
Crystallization and gelation in colloidal systems with short-ranged attractive interactions
cond-mat.softAndrea Fortini, Eduardo Sanz, Marjolein Dijkstra
We systematically study the relationship between equilibrium and non-equilibrium phase diagrams of a system of short-ranged attractive colloids. Using Monte Carlo and Brownian dynamics simulations we find a window of enhanced crystallization that is limited at high interaction strength by a slowing down of the dynamics and at low interaction strength by the
Drastic changes in the molecular absorption at redshift z=0.89 toward the quasar PKS 1830-211
astro-phSebastien Muller, Michel Guelin
A 12 year-long monitoring of the absorption caused by a z=0.89 spiral galaxy on the line of sight to the radio-loud gravitationally lensed quasar PKS 1830-211 reveals spectacular changes in the HCO+ and HCN (2-1) line profiles. The depth of the absorption toward the quasar NE image increased by a factor of ~3 in 1998-1999 and subsequently decreased by a fact
The Delicate Electronic and Magnetic Structure of the LaOFePn System (Pn = pnictogen)
cond-mat.mtrl-sciS. Lebegue, Z. P. Yin, W. E. Pickett
The occurrence of high temperature superconductivity, and the competition with magnetism, in stoichiometric and doped LaOFeAs and isostructural iron-oxypnictides is raising many fundamental questions about the electronic structure and magnetic interactions in this class of materials. There are now sufficient experimental data that it may be possible to ident
Non-zero density QCD by the Taylor expansion method: The isentropic equation of state, hadronic fluctuations and more
hep-latChuan Miao, Christian Schmidt, for RBC-Bielefeld Collaboration
We discuss the Taylor expansion approach to non-zero baryon chemical potential ($\mu_B$) and present results on expanion coefficients of the pressure and energy density up to the 6-th order in $\mu_B$. Calculations have been performed with (2+1)-flavor of improved staggerd fermions (p4fat3) and almost physical masses on lattices with temporal extent of four
Christian Schmid, for RBC-Bielefeld, HotQCD Collaborations
We present results on the QCD equation of state, obtained with two different improved dynamical staggered fermion actions and almost physical quark masses. Lattice cut-off effect are discussed in detail as results for three different lattice spacings are available now, i.e. results have been obtained on lattices with temporal extent of $N_τ=4,6$ and 8. Furth
F. Mueller, S. Heugel, L. J. Wang
Linear mechanical oscillators have been applied to measure very small forces, mostly with the help of noise suppression. In contrast, adding noise to non-linear oscillators can improve the measurement conditions. Here, this effect of stochastic resonance is demonstrated in a macroscopic torsion oscillator, for an optomechanical non-linear potential. The sign
Optimizing Binary Code Produced by Valgrind (Project Report on Virtual Execution Environments Course - AVExe)
cs.PLFilipe Cabecinhas, Nuno Lopes, Renato Crisostomo, Luis Veiga
Valgrind is a widely used framework for dynamic binary instrumentation and its mostly known by its memcheck tool. Valgrind's code generation module is far from producing optimal code. In addition it has many backends for different CPU architectures, which difficults code optimization in an architecture independent way. Our work focused on identifying sub
B. Gendre, A. Galli, M. Boer
We investigate the clustering of afterglow light curves observed at X-ray and optical wavelengths. We have constructed a sample of 61 bursts with known distance and X-ray afterglow. GRB sources can be divided in three classes, namely optical and X-ray bright afterglows, optical and X-ray dim one s, and optically bright -X-ray dim ones. We argue that this clu
Sayantan Majumdar, A. K. Sood
We show that the shear rate at a fixed shear stress in a micellar gel in a jammed state exhibits large fluctuations, showing positive and negative values, with the mean shear rate being positive. The resulting probability distribution functions (PDF's) of the global power flux to the system vary from Gaussian to non-Gaussian, depending on the driving str
Michel Droz, Janusz Szwabiński, György Szabó
We study a spatial Prisoner's dilemma game with two types (A and B) of players located on a square lattice. Players following either cooperator or defector strategies play Prisoner's Dilemma games with their 24 nearest neighbors. The players are allowed to adopt one of their neighbor's strategy with a probability dependent on the payoff differenc
Elias Baro, Margarita Otero
We work over an o-minimal expansion of a real closed field. The o-minimal homotopy groups of a definable set are defined naturally using definable continuous maps. We prove that any two semialgebraic maps which are definably homotopic are also semialgebraically homotopic. This result together with the study of semialgebraic homotopy done by H. Delfs and M. K
L. Marconi, L. Praly, A. Isidori
In this paper we present a general tool to handle the presence of zero dynamics which are asymptotically but not locally exponentially stable in problems of robust nonlinear stabilization by output feedback. We show how it is possible to design locally Lipschitz stabilizers under conditions which only rely upon a partial detectability assumption on the contr
Renormalized theory of the ion cyclotron turbulence in magnetic field--aligned plasma shear flow
physics.plasm-phV. S. Mikhailenko, V. V. Mikhailenko, K. N. Stepanov, N. A. Azarenkov
The analytical treatment of nonlinear evolution of the shear-flow-modified current driven ion cyclotron instability and shear-flow-driven ion cyclotron kinetic instabilities of magnetic field--aligned plasma shear flow is presented. Analysis is performed on the base of the nonlinear dispersion equation, which accounts for a new combined effect of plasma turb
H. Dias Alves, A. S. Molinari, H. Xie, A. F. Morpurgo
The electronic properties of interfaces between two different solids can differ strikingly from those of the constituent materials. For instance, metallic conductivity, and even superconductivity, have been recently discovered at interfaces formed by insulating transition metal oxides. Here we investigate interfaces between crystals of conjugated organic mol
C. Adami, R. Gavazzi, J. C. Cuillandre, F. Durret
We have then searched for preferential orientations of faint galaxies in the Coma cluster (down I_Vega~-11.5). By applying a deconvolution method to deep u* and I band images of the Coma cluster, we were able to recover orientations down to faint magnitudes. No preferential orientations are found in more than 95% of the cluster, and the brighter the galaxies
Comparative study of the rovibrational properties of heteronuclear alkali dimers in electric fields
physics.atom-phR. Gonzalez-Ferez, M. Mayle, P. Sanchez-Moreno, P. Schmelcher
A comparative study of the effect of a static homogeneous electric field on the rovibrational spectra of several polar dimers in their $\textrm{X}^1Σ^+$ electronic ground state is performed. Focusing upon the rotational ground state within each vibrational band, results for energies and various expectation values are presented. For moderate field strengths t
Francisco J. Plaza Martin
The construction of families of Sato Grassmannians, their determinant line bundles and the extensions induced by them are given. The base scheme is an arbitrary scheme.
Solving the two-center nuclear shell-model problem with arbitrarily-orientated deformed potentials
nucl-thAlexis Diaz-Torres
A general new technique to solve the two-center problem with arbitrarily-orientated deformed realistic potentials is demonstrated, which is based on the powerful potential separable expansion method. As an example, molecular single-particle spectra for $^{12}$C + $^{12}$C $\to$ $^{24}$Mg are calculated using deformed Woods-Saxon potentials. These clearly sho
F. Cedo, E. Jespers, J. Okninksi
The class of finitely presented algebras over a field $K$ with a set of generators $a_{1},..., a_{n}$ and defined by homogeneous relations of the form $a_{1}a_{2}... a_{n} =a_{σ(a)} a_{σ(2)} ... a_{σ(n)}$, where $σ$ runs through a subset $H$ of the symmetric group $\Sym_{n}$ of degree $n$, is introduced. The emphasis is on the case of a cyclic subgroup $H$ o
SU(2) and SU(3) chiral perturbation theory analyses on meson and baryon masses in 2+1 flavor lattice QCD
hep-latCS Collaboration, D. Kadoh, S. Aoki, N. Ishii
We investigate the quark mass dependence of meson and baryon masses obtained from 2+1 flavor dynamical quark simulations performed by the PACS-CS Collaboration. With the use of SU(2) and SU(3) chiral perturbation theories up to NLO, we examine the chiral behavior of the pseudoscalar meson masses and the decay constants in terms of the degenerate up-down quar
Masatomo Uehara, Kenich Ashikawa, Yoshimasa Aka, Yoshihide Kimishima
Hole carrier doping has been tried to pseudo-low-dimensional material La2RuO5 by substituting La3+ with Cd2+. Single phased samples of La2-xCdxRuO5 with x up to 0.5 have been successfully obtained and also high pressure O2 annealing has been performed to the x=0.5 sample. Although the formal ionic state of Ru is expected to increase from 4+ (at x=0) to 4.5+
The R.I. Pimenov unified gravitation and electromagnetism field theory as semi-Riemannian geometry
gr-qcN. A. Gromov
More then forty years ago R.I. Pimenov introduced a new geometry -- semi-Riemannian one -- as a set of geometrical objects consistent with a fibering $ pr: M_n \to M_m.$ He suggested the heuristic principle according to which the physically different quantities (meter, second, coulomb etc.) are geometrically modelled as space coordinates that are not superpo
P. Guillard, F. Boulanger
Spitzer space telescope observations led to the surprising detection of a diverse set of extragalactic sources whose infrared spectra are dominated by line emission of molecular hydrogen (H2). The absence or relative weakness of typical signs of star formation (like dust features, lines of ionized gas) suggest the presence of large quantities of H2 gas with
Alireza Abdollahi, A. Mohammadi Hassanabadi
We associate a graph $\mathcal{C}_G$ to a non locally cyclic group $G$ (called the non-cyclic graph of $G$) as follows: take $G\backslash Cyc(G)$ as vertex set, where $Cyc(G)=\{x\in G | < x,y> \text{is cyclic for all} y\in G\}$ is called the cyclicizer of $G$, and join two vertices if they do not generate a cyclic subgroup. For a simple graph $Γ$, $w(Γ)$ den
Novel critical exponent of magnetization curves near the ferromagnetic quantum phase transitions of Sr1-xAxRuO3 (A = Ca, La0.5Na0.5, and La)
cond-mat.str-elY. Itoh, T. Mizoguchi, K. Yoshimura
We report a novel critical exponent delta=3/2 of magnetization curves M=H^{1/delta} near the ferromagnetic quantum phase transitions of Sr1-xAxRuO3 (A = Ca, La0.5Na0.5, and La), which the mean field theory of the Ginzburg-Landau-Wilson type fails to reproduce. The effect of dirty ferromagnetic spin fluctuations might be a key.
Siddhartha Gadgil, Tejas Kalelkar
We interpret a normal surface in a (singular) three-manifold in terms of the homology of a chain complex. This allows us to study the relation between normal surfaces and their quadrilateral co-ordinates. Specifically, we give a proof of an (unpublished) observation independently given by Casson and Rubinstein saying that quadrilaterals determine a normal su
Y. Momany, S. Ortolani, C. Bonatto, E. Bica
We employ the recently installed near infrared Multi-Conjugate Adaptive optics demonstrator (MAD) to determine basic properties of a newly identified, old and distant, Galactic open cluster (FSR1415). The MAD facility remarkably approaches the diffraction limit, reaching a resolution of 0.07 arcsec (in K), that is also uniform in a field of ~1.8 arcmin in di
Measurement of the Differential Branching Fraction and Forward-Backward Asymmetry for B->K(*)l+l-
hep-exThe Belle Collaboration, I. Adachi
We study B->K(*)l+l- decays based on a large data sample of 657 million BB pairs collected with the Belle detector at the KEKB e+e- collider. The differential branching fraction, the isospin asymmetry, the K* polarization, and the forward-backward asymmetry (A_FB) as functions of q^2 are reported. The fitted A_FB spectrum tends to be shifted toward the posit
Belle Collaboration, I. Adachi
The differential cross section for the process $γγ\to π^0 π^0$ has been measured in the kinematic range 0.6 GeV $< W < 4.1$ GeV, $|\cos θ^*|<0.8$ in energy and pion scattering angle, respectively, in the $γγ$ center-of-mass system. The results are based on a 223 fb$^{-1}$ data sample collected with the Belle detector at the KEKB $e^+ e^-$ collider. Using the
Effect of many-body quantum fluctuations on matrix Berry phases of a two-dimensional n-type semiconductor quantum dot
cond-mat.mes-hallS. C. Kim, Y. J. Kim, P. S. Park, N. Y. Hwang
In the presence of spin-orbit coupling and inversion symmetry of the lateral confinement potential a single electron does not exhibit matrix Berry phases in quasi-two-dimensional semiconductor quantum dots. In such a system we investigate whether many-body correlation effects can lead to finite matrix Berry phases. We find that the transformation properties
Wilson Wong, Wei Liu, Mohammed Bennamoun
An increasing number of approaches for ontology engineering from text are gearing towards the use of online sources such as company intranet and the World Wide Web. Despite such rise, not much work can be found in aspects of preprocessing and cleaning dirty texts from online sources. This paper presents an enhancement of an Integrated Scoring for Spelling er
Comment on "Electron screening and excitonic condensation in double-layer graphene systems"
cond-mat.mes-hallR. Bistritzer, H. Min, J. J. Su, A. H. MacDonald
The influence of screening on the condensed state of bilayer graphene is studied within the framework of the Thomas Fermi approximation. We find that screening has little effect on the Kosterlitz-Thouless temperature in the strongly interacting regime. Furthermore, we predict that the phase transition to the condensed state is first order.
Improved Seed Methods for Symmetric Positive Definite Linear Equations with Multiple Right-hand Sides
math-phAbdou M. Abdel-Rehim, Ronald B. Morgan, Walter Wilcox
We consider symmetric positive definite systems of linear equations with multiple right-hand sides. The seed conjugate gradient method solves one right-hand side with the conjugate gradient method and simultaneously projects over the Krylov subspace thus developed for the other right-hand sides. Then the next system is solved and used to seed the remaining o
Robert Lohmayer, Herbert Neuberger, Tilo Wettig
It is shown that the simplest multiplicative random complex matrix model generalizes the large-N phase structure found in the unitary case: A perturbative regime is joined to a nonperturbative regime at a point of nonanalyticity.
Han Chuen Lim, Akio Yoshizawa, Hidemi Tsuchida, Kazuro Kikuchi
We report the first experimental demonstration of wavelength-multiplexed entanglement distribution. 44 channels of highly-entangled photon-pairs from one single broadband source are distributed over 10 km of fiber.
George Androulakis, Nigel Kalton, Adi Tcaciuc
We use the Gowers block Ramsey theorem to characterize Banach spaces containing isomorphs of $\ell_p$ (for some $1 \leq p < \infty$) or $c_0$.
Patrick McDonald, Uros Seljak
We show how to use multiple tracers of large-scale density with different biases to measure the redshift-space distortion parameter beta=f/b=(dlnD/dlna)/b (where D is the growth rate and a the expansion factor), to a much better precision than one could achieve with a single tracer, to an arbitrary precision in the low noise limit. In combination with the po
A high resolution view of the jet termination shock in a hot spot of the nearby radio galaxy Pictor A: implications for X-ray models of radio galaxy hot spots
astro-phS. J. Tingay, E. Lenc, G. Brunetti, M. Bondi
Images made with the VLBA have resolved the region in a nearby radio galaxy, Pictor A, where the relativistic jet that originates at the nucleus terminates in an interaction with the intergalactic medium, a so-called radio galaxy hot spot. This image provides the highest spatial resolution view of such an object to date (16 pc), more than three times better
B. Abu-Ibrahim, S. Iwasaki, W. Horiuchi, A. Kohama
We systematically calculate the total reaction cross sections of oxygen isotopes, $^{15-24}$O, on a $^{12}$C target at high energies using the Glauber theory. The oxygen isotopes are described with Slater determinants generated from a phenomenological mean-field potential. The agreement between theory and experiment is generally good, but a sharp increase of
S. De Baerdemacker, K. Heyde, V. Hellemans
The spectral properties of a tractable collective model Hamiltonian are studied. The potential energy is truncated up to quartic terms in the quadrupole deformation variables, incorporating vibrational, $γ$-independent rotational and axially deformed rotational structures. These physically significant limits are analysed in detail and confronted with well-es
Shigeo Yamauchi, Ken Ebisawa, Yasuo Tanaka, Katsuji Koyama
In order to elucidate origin of the Galactic Ridge X-ray Emission, we analyzed Suzaku data taken at various regions along the Galactic plane and studied their Fe-K emission line features. Suzaku resolved the Fe line complex into three narrow lines at ~6.4 keV,~6.7 keV and ~6.97 keV, which are K-lines from neutral (or low-ionized), He-like, and H-like iron io
Yan-Yu Ren, Wei-Ning Zhang, Jian-Li Liu
We develop a method for detecting the inhomogeneity of the pion-emitting sources produced in ultra-relativistic heavy ion collisions, through event-by-event two-pion Bose-Einstein correlations. The root-mean-square of the error-inverse-weighted fluctuations between the two-pion correlation functions of single and mixed events are useful observables for the d
D. T. da Silva, M. L. L. da Silva, J. N. de Quadros, D. Hadjimichef
Extensively applied to both light and heavy meson decay and standing as one of the most successful strong decay models is the $3^P_0$ model, in which $q\bar{q}$ pair production is the dominant mechanism. The pair production can be obtained from the non-relativistic limit of a microscopic interaction Hamiltonian involving Dirac quark fields. The evaluation of
Images IV: Strong evolution of the oxygen abundance in gaseous phases of intermediate mass galaxies since z=0.8
astro-phM. Rodrigues, F. Hammer, H. Flores, M. Puech
Intermediate mass galaxies (logM(Msun)>10) at z~0.6 are the likeliest progenitors of the present-day numerous population of spirals. There is growing evidence that they have evolved rapidly since the last 6 to 8 Gyr ago, and likely have formed a significant fraction of their stellar mass, often showing perturbed morphologies and kinematics. We have gathered
Nimish P. Hathi
My dissertation presents results from three recent investigations in the Hubble Ultra Deep Field (HUDF) focusing on understanding structural and physical properties of high redshift galaxies. Here I summarize results from these studies. This thesis work was conducted at Arizona State University under the guidance of Prof. Rogier Windhorst and Prof. Sangeeta
Andrew M. Childs
Quantum walk is one of the main tools for quantum algorithms. Defined by analogy to classical random walk, a quantum walk is a time-homogeneous quantum process on a graph. Both random and quantum walks can be defined either in continuous or discrete time. But whereas a continuous-time random walk can be obtained as the limit of a sequence of discrete-time ra
Russ Woodroofe
Inspired by several recent papers on the edge ideal of a graph G, we study the equivalent notion of the independence complex of G. Using the tool of vertex decomposability from geometric combinatorics, we show that 5-chordal graphs with no chordless 4-cycles are shellable and sequentially Cohen-Macaulay. We use this result to characterize the obstructions to
P. -L. Giscard
We present a method for calculating the Aharonov-Anandan phase for time-independent Hamiltonians that avoids the calculation of evolution operators. We compare the generic method used to calculate the Aharonov-Anandan phase with the method proposed here through four examples; a spin-1/2 particle in a constant magnetic field, an arbitrary infinite-sized Hamil
Correlation between microstructure and magnetotransport in organic semiconductor spin valve structures
cond-mat.mtrl-sciYaohua Liu, Shannon M. Watson, Taegweon Lee, Justin M. Gorham
We have studied magnetotransport in organic-inorganic hybrid multilayer junctions. In these devices, the organic semiconductor (OSC) Alq$_3$ (tris(8-hydroxyquinoline) aluminum) formed a spacer layer between ferromagnetic (FM) Co and Fe layers. The thickness of the Alq$_3$ layer was in the range of 50-150 nm. Positive magnetoresistance (MR) was observed at 4.
Quantum switching at a mean-field instability of a Bose-Einstein condensate in an optical lattice
cond-mat.otherV. S. Shchesnovich, V. V. Konotop
It is shown that bifurcations of the mean-field dynamics of a Bose-Einstein condensate can be related with the quantum phase transitions of the original many-body system. As an example we explore the intra-band tunneling in the two-dimensional optical lattice. Such a system allows for easy control by the lattice depth as well as for macroscopic visualization
Rodolfo Casana, Manoel M. Ferreira, Josberg S. Rodrigues
We study the finite temperature properties of the Maxwell-Carroll-Field-Jackiw (MCFJ) electrodynamics for a purely spacelike background. Starting from the associated finite temperature partition function, a modified black body spectral distribution is obtained. We thus show that, if the CMB radiation is described by this model, the spectrum presents an aniso
Daniel Caro
Let $\V$ be a mixed characteristic complete discrete valuation ring with perfect residue field $k$. We solve Berthelot's conjectures on the stability of the holonomicity over smooth projective formal $\V$-schemes. Then we build a category of complexes of arithmetic $\D$-modules over quasi-projective $k$-varieties with bounded, $F$-holonomic cohomology. W