November 2008 arXiv papers — page 31
Showing 3,001–3,100 of 4,899 papers
Yuichi Hoshino
Minkowski structure of the Fermion propagator in QED$_{2+1}$ is evaluated using dispersion like method Including massive fermion loop to the photon spectral function there is no infrared divergences in the gauge d=-1.Screening effects suppress the chiral order parmeter for small numbers of fermion flavour N.We evaluate the order parameter as a function of co
Yoram Burak, Ila R. Fiete
Grid cells in the rodent entorhinal cortex display strikingly regular firing responses to the animal's position in 2-D space, and have been hypothesized to form the neural substrate for dead-reckoning. However, in previous models suggested for grid cell activity, errors accumulate rapidly in the integration of velocity inputs. To produce grid-cell like r
Nithin Nagaraj, Mahesh C. Shastry, Prabhakar G. Vaidya
Grebogi, Ott and Yorke (Phys. Rev. A 38(7), 1988) have investigated the effect of finite precision on average period length of chaotic maps. They showed that the average length of periodic orbits ($T$) of a dynamical system scales as a function of computer precision ($\epsilon$) and the correlation dimension ($d$) of the chaotic attractor: $T \sim \epsilon^{
Deyang Yu
Design details of a 127 degree electrostatic cylindrical spectrometer equipped with a position-sensitive micro-channel plate detector for measuring the sputtered ions in collisions of highly charged ions with solid surface is described. The nonlinear relationship between the point of fall versus the ionic energy, the blurring of the point of fall caused by t
Yong-Lu Liu, Ming-Qiu Huang
Based on QCD conformal partial wave expansion to leading order conformal spin accuracy, we present the light-cone distribution amplitudes (DAs) of $Σ$ and $Λ$ baryons up to twist 6. It is concluded that fourteen ndependent DAs are needed to describe the valence three-quark states of the baryons at small transverse separations. The nonperturbative parameters
Hiroki Sumi, Mariusz Urbanski
We consider the dynamics of semi-hyperbolic semigroups generated by finitely many rational maps on the Riemann sphere. Assuming that the nice open set condition holds it is proved that there exists a geometric measure on the Julia set with exponent $h$ equal to the Hausdorff dimension of the Julia set. Both $h$-dimensional Hausdorff and packing measures are
Nonlinear Stresses and Temperatures in Transient Adiabatic and Shear Flows via Nonequilibrium Molecular Dynamics -- Three Definitions of Temperature
nlin.CDWm. G. Hoover, C. G. Hoover
We compare nonlinear stresses and temperatures for adiabatic shear flows, using up to 262,144 particles, with those from corresponding homogeneous and inhomogeneous flows. Two varieties of kinetic temperature tensors are compared to the configurational temperatures. This comparison leads to an improved form for the local and instantaneous smooth-particle ave
Michael R. R. Good
A scalar field gravitational analog of the Reissner-Nordstrom solution is investigated. The nonlinear Newtonian model has an upper-limit of charge for a central mass which agrees with the general relativistic condition required for the existence of the black hole horizon. The maximum limit for accumulation by bombardment of charged particles is found. The ai
J. R. North, J. Davis, J. G. Robertson, T. R. Bedding
We have used the Sydney University Stellar Interferometer (SUSI) to measure the angular diameter of the F9 V star beta Virginis. After correcting for limb darkening and combining with the revised Hipparcos parallax, we derive a radius of 1.703 +/- 0.022 R_sun (1.3%). We have also calculated the bolometric flux from published measurements which, combined with
Comment on "Conjectures on exact solution of three-dimensional (3D) simple orthorhombic Ising lattices" [arXiv:0705.1045]
cond-mat.stat-mechJacques H. H. Perk
It is shown that a recent article by Z.-D. Zhang [arXiv:0705.1045] is in error and violates well-known theorems.
I. Y. Dodin, N. J. Fisch
For a nonrelativistic classical particle undergoing arbitrary oscillations, the generalized effective potential Y is derived from nonlinear eigenfrequencies of the particle-field system. Specifically, the ponderomotive potential is extended to a nonlinear oscillator, resulting in multiple branches near the primary resonance. For a pair of natural frequencies
T. D. Kinman, Heather L. Morrison, Warren R. Brown
We study the Milky Way region Z<3.0 kpc, where the thick disk and inner halo overlap, by using the kinematics of local blue horizontal branch (BHB) stars (within 1 kpc) and new samples of BHB stars and A-type stars from the Century Survey. We derive Galactic U,V,W velocities for these BHB and A-type star samples using proper motions from the NOMAD catalog. T
Gary J. Ferland
I review recent studies of the emission-line regions in Orion and M17. Both have similar geometries, a bubble of hot shocked gas surrounding the central star cluster, with H^+, H^0, and H_2 regions, often referred to as H II regions, PDRs, and molecular clouds, forming successive shells on the surface of a molecular cloud. The magnetic fields in the H^0 regi
Paul D. Lasky, Hajime Sotani, Dimitrios Giannios
Bekenstein's Tensor-Vector-Scalar (TeVeS) theory has had considerable success in explaining various phenomena without the need for dark matter. However, it is difficult to observationally discern the differences between TeVeS and predictions made within the Lambda-cold dark matter concordance model. This implies that alternative tests are required that i
J. Xavier Prochaska, Arthur M. Wolfe
We present new results on the frequency distribution of projected HI column densities f(N,X), total comoving covering fraction, and integrated mass densities rho_HI of high redshift, HI `disks' from a survey of damped Lya systems (DLAs) in the Sloan Digital Sky Survey, Data Release 5. For the full sample spanning z=2.2 to 5 [738 DLAs], f(N,X) is well fit
Matias F. Dahl
In this short note we prove that every contact form on a 3-manifold M induces a solution to Maxwell's equations on M.
Determining Quasar Black Hole Mass Functions from their Broad Emission Lines: Application to the Bright Quasar Survey
astro-phBrandon C. Kelly, Marianne Vestergaard, Xiaohui Fan
We describe a Bayesian approach to estimating quasar black hole mass functions (BHMF) when using the broad emission lines to estimate black hole mass. We show how using the broad line mass estimates in combination with statistical techniques developed for luminosity function estimation leads to statistically biased results. We derive the likelihood function
C. Ngeow, S. Kanbur, H. Neilson, A. Nanthakumar
In this Paper, we have derived Cepheid period-luminosity (P-L) relations for the Large Magellanic Cloud (LMC) fundamental mode Cepheids, based on the data released from OGLE-III. We have applied an extinction map to correct for the extinction of these Cepheids. In addition to the VIW band P-L relations, we also include JHK and four Spitzer IRAC band P-L rela
Empirical Constraints on Trojan Companions and Orbital Eccentricities in 25 Transiting Exoplanetary Systems
astro-phN. Madhusudhan, Joshua N. Winn
We present a search for Trojan companions to 25 transiting exoplanets. We use the technique of Ford & Gaudi, in which a difference is sought between the observed transit time and the transit time that is calculated by fitting a two-body Keplerian orbit to the radial-velocity data. This technique is sensitive to the imbalance of mass at the L4/L5 points of th
Rhiannon Gwyn, Stephon Alexander, Robert H. Brandenberger, Keshav Dasgupta
Large-scale magnetic fields are observed today to be coherent on galactic scales. While there exists an explanation for their amplification and their specific configuration in spiral galaxies -- the dynamo mechanism -- a satisfying explanation for the original seed fields required is still lacking. Cosmic strings are compelling candidates because of their sc
Clean Kinematic Samples in Dwarf Spheroidals: An Algorithm for Evaluating Membership and Estimating Distribution Parameters When Contamination is Present
astro-phMatthew G. Walker, Mario Mateo, Edward W. Olszewski, Bodhisattva Sen
(abridged) We develop an algorithm for estimating parameters of a distribution sampled with contamination, employing a statistical technique known as ``expectation maximization'' (EM). Given models for both member and contaminant populations, the EM algorithm iteratively evaluates the membership probability of each discrete data point, then uses thos
Sebastian Haan, Eva Schinnerer, Eric Emsellem, Santiago Garcia-Burillo
To examine the role of the host galaxy structure in fueling nuclear activity, we estimated gas flow rates from several kpc down to the inner few 10 pc for seven nearby spiral galaxies, selected from the NUGA sample (NUclei of GAlaxies). We calculated gravitational torques from near-IR images and determined gas in/out-flow rates as a function of radius and lo
Yingchuan Li, Stefano Profumo, Michael Ramsey-Musolf
It is conventional wisdom that successful electroweak baryogenesis in the Minimal Supersymmetric extension of the Standard Model (MSSM) is in tension with the non-observation of electric dipole moments (EDMs), since the level of CP-violation responsible for electroweak baryogenesis is believed to generate unavoidably large EDMs. We show that CP-violation in
Rudy C. Gilmore, Piero Madau, Joel R. Primack, Rachel S. Somerville
We present two models for the cosmological UV background light, and calculate the opacity of GeV gamma--rays out to redshift 9. The contributors to the background include 2 possible quasar emissivities, and output from star--forming galaxies as determined by recent a semi--analytic model (SAM) of structure formation. The SAM used in this work is based upon a
Alexander Miller, Victor Reiner
We conjecture a strong property for the up and down maps U and D in an r-differential poset: DU+tI and UD+tI have Smith normal forms over Z[t]. In particular, this would determine the integral structure of the maps U, D, UD, DU, including their ranks in any characteristic. As evidence, we prove the conjecture for the Young-Fibonacci lattice YF studied by Oka
I. Chaudhuri, F. Inam, D. A. Drabold
We present a microscopic picture of silver dynamics in GeSe$_{3}$:Ag glass obtained from {\it ab initio} simulation. The dynamics of Ag is explored at two temperatures, 300K and 700K. In the relaxed network, Ag occupies bond centers between suitably separated host sites. At 700K, Ag motion proceeds via a trapping-release dynamics, between "super traps
Samuel Peláez, Carlo Guerrero, Ricardo Paredes, Pedro A. Serena
We present and discuss an algorithm to identify and characterize the long icosahedral structures (staggered pentagonal nanowires with 1-5-1-5 atomic structure) that appear in Molecular Dynamics simulations of metallic nanowires of different species subjected to stretching. The use of the algorithm allows the identification of pentagonal rings forming the ico
Vakhid Masagutov
We prove that every homomorphism $\mathcal{O}^E_ζ\to\mathcal{O}^F_ζ$, with $E$ and $F$ Banach spaces and $ζ\in\mathbb{C}^m$, is induced by a $\mathop{\mathrm{Hom}}(E,F)$-valued holomorphic germ, provided that $1\leq m<\infty$. A similar structure theorem is obtained for the homomorphisms of type $\mathcal{O}^E_ζ\to\mathcal{S}_ζ$, where $\mathcal{S}_ζ$ is a s
Power Spectra in a Zero-Range Process on a Ring: Total Occupation Number in a Segment
cond-mat.stat-mechA. G. Angel, R. K. P. Zia
We study the dynamics of density fluctuations in the steady state of a non-equilibrium system, the Zero-Range Process on a ring lattice. Measuring the time series of the total number of particles in a \emph{segment} of the lattice, we find remarkable structures in the associated power spectra, namely, two distinct components of damped-oscillations. The essen
Elizabeth Groves, B. D. Clader, J. H. Eberly
The prospect of self-consistent propagation of more than two pulses contemporaneously through multi-resonant media raises open questions: whether soliton solutions exist, and whether a useful generalization of two-level pulse Area can be found. We answer these questions positively for the case of four pulses interacting in combined V and Lambda fashion with
Vladimir L. Averbukh
The work is devoted to a problem of search of metaphors for interactive systems and systems based on Virtual Reality (VR) environments. The analysis of magic fairy tales as a source of metaphors for interface and virtual reality is offered. Some results of design process based on magic metaphors are considered.
Fishing in Tidal Streams: New Radial Velocity and Proper Motion Constraints on the Orbit of the Anticenter Stream
astro-phCarl J. Grillmair, Jeffrey L. Carlin, Steven R. Majewski
We have obtained radial velocity measurements for stars in two, widely-separated fields in the Anticenter Stream. Combined with SDSS/USNO-B proper motions, the new measurements allow us to establish that the stream is on a nearly circular, somewhat inclined, prograde orbit around the Galaxy. While the orbital eccentricity is similar to that previously determ
Scott D. Hyman, Rudy Wijnands, T. Joseph W. Lazio, Sabyasachi Pal
We report the detection of a new transient radio source, GCRT J1742-3001, located ~1 degree from the Galactic center. The source was detected ten times from late 2006 to 2007 May in our 235 MHz transient monitoring program with the Giant Metrewave Radio Telescope (GMRT). The radio emission brightened in about one month, reaching a peak observed flux density
V. Casasola, S. Garcia-Burillo, F. Combes, L. K. Hunt
We present a review on bar pattern speeds from preliminary results in the context of the Nuclei of Galaxies (NUGA) project. The large variety of molecular circumnuclear morphologies found in NUGA is a challenging result that implies the refinement of current dynamical models of galaxies.
H. Casini, M. Huerta, L. Leitao
In three dimensions there is a logarithmically divergent contribution to the entanglement entropy which is due to the vertices located at the boundary of the region considered. In this work we find the corresponding universal coefficient for a free Dirac field, and extend a previous work in which the scalar case was treated. The problem is equivalent to find
Mikhail E. Shaposhnikov, Igor I. Tkachev
We propose a scheme leading to a non-perturbative definition of lattice field theories which are scale-invariant on the quantum level. A key idea of the construction is the replacement of the lattice spacing by a propagating dynamical field -- the dilaton. We describe how to select non-perturbatively the phenomenologically viable theories where the scale inv
Dikran Dikranjan, Gábor Lukács
In this paper, we present families of quasi-convex sequences converging to zero in the circle group T, and the group J_3 of 3-adic integers. These sequences are determined by an increasing sequences of integers. For an increasing sequence \underline{a}=\{a_n\} of integers, put g_n=a_{n+1}-a_n. We prove that: (a) the set \{0\}\cup\{\pm 3^{-(a_n+1)} : n\in N\}
Bojko Bakalov, Todor MIlanov
Using Picard--Lefschetz periods for the singularity of type $A_N$, we construct a projective representation of the Lie algebra of differential operators on the circle with central charge $h:=N+1$. We prove that the total descendant potential $\D_{A_N}$ of $A_N$-singularity is a highest weight vector. It is known that $\D_{A_N}$ can be interpreted as a genera
Timelike Geodesic Currents in the Stationary, Axisymmetric, Force-free Magnetosphere of a Kerr Black Hole
gr-qcGovind Menon, Charles Dermer
The structural properties of geodesic currents in an ambient Kerr background is studied from an analytical point of view. The geodesics in the congruence correspond to charged particles that carry energy and angular momentum from the black hole through the Blandford-Znajek mechanism. It is shown that the resulting magnetosphere naturally satisfies the Znajek
Enhancement of quasiparticle recombination in Ta and Al superconductors by implantation of magnetic and nonmagnetic atoms
cond-mat.supr-conR. Barends, S. van Vliet, J. J. A. Baselmans, S. J. C. Yates
The quasiparticle recombination time in superconducting films, consisting of the standard electron-phonon interaction and a yet to be identified low temperature process, is studied for different densities of magnetic and nonmagnetic atoms. For both Ta and Al, implanted with Mn, Ta and Al, we observe an increase of the recombination rate. We conclude that the
Thomas Heinzl, Anton Ilderton
We give a non-technical overview of QED effects arising in the presence of ultra-strong electromagnetic fields highlighting the new prospects provided by a realisation of the ELI laser facility.
Characterization and collection of information from heterogeneous multimedia sources with users' parameters for decision support
cs.MMCharles A. B. Robert
No single information source can be good enough to satisfy the divergent and dynamic needs of users all the time. Integrating information from divergent sources can be a solution to deficiencies in information content. We present how Information from multimedia document can be collected based on associating a generic database to a federated database. Informa
A. T. Okazaki, G. E. Romero, S. P. Owocki
LS 5039 is a TeV gamma-ray binary with extended radio emission. It consists of a compact object in the mildly eccentric (e=0.35), 3.9-day orbit around a massive O star. The nature of the compact object is not yet established. In this paper, assuming that the compact object is a black hole, we study the accretion of O-star wind by the black hole, by performin
Tomi S. Koivisto
A canonic scalar field minimally coupled to a disformal metric generated by the field itself is considered. Causality and stability conditions are derived for such a field. Cosmological effects are studied and it is shown that the disformal modification could viably trigger an acceleration after a scaling matter era, thus possibly alleviating the coincidence
Patrick Slane
The extended nebulae formed as pulsar winds expand into their surroundings provide information about the composition of the winds, the injection history from the host pulsar, and the material into which the nebulae are expanding. Observations from across the electromagnetic spectrum provide constraints on the evolution of the nebulae, the density and composi
Soumaya Elkadiri, Philippe Pernelle, Miguel Delattre, Abdelaziz Bouras
This paper aims at analyzing the problems related to collaborative work using a PLM system. This research is mainly focused on the organisational aspects of SMEs involved in networks composed of large companies, subcontractors and other industrial partners. From this analysis, we propose the deployment of an approach based on an observation process of tracks
Pilotage des processus collaboratifs dans les systèmes PLM. Quels indicateurs pour quelle évaluation des performances ?
cs.SESoumaya Elkadiri, Philippe Pernelle, Miguel Delattre, Abdelaziz Bouras
Les entreprises qui collaborent dans un processus de développement de produit ont besoin de mettre en oeuvre une gestion efficace des activités collaborative. Malgré la mise en place d'un PLM, les activités collaborative sont loin d'être aussi efficace que l'on pourrait s'y attendre. Cet article propose une analyse des problématiques de la co
François Boyer, Eric Falcon
We report the observation of wave turbulence on the surface of a ferrofluid mechanically forced and submitted to a static normal magnetic field. We show that magnetic surface waves arise only above a critical field. The power spectrum of their amplitudes displays a frequency-power law leading to the observation of a magnetic wave turbulence regime which is e
Matter-Wave Solitons in the Presence of Collisional Inhomogeneities: Perturbation theory and the impact of derivative terms
quant-phS. Middelkamp, P. G. Kevrekidis, D. J. Frantzeskakis, P. Schmelcher
We study the dynamics of bright and dark matter-wave solitons in the presence of a spatially varying nonlinearity. When the spatial variation does not involve zero crossings, a transformation is used to bring the problem to a standard nonlinear Schrodinger form, but with two additional terms: an effective potential one and a non-potential term. We illustrate
L. S. Geng, E. Oset, J. R. Pelaez, L. Roca
By describing within the chiral unitary approach the s-wave interaction of the vector meson nonet with the octet of pseudoscalar Goldstone Bosons, we find that the main component of the axial vector mesons b_1(1235), h_1(1170), h_1(1380), a_1(1260), f_1(1285) and the two states associated to the K_1(1270) does not follow the QCD dependence on the number of c
Gianluca Crippa, Chloé Jimenez, Aldo Pratelli
Consider a distribution of citizens in an urban area in which some services (supermarkets, post offices...) are present. Each citizen, in order to use a service, spends an amount of time which is due both to the travel time to the service and to the queue time waiting in the service. The choice of the service to be used is made by every citizen in order to b
I. Knezevic, E. B. Ramayya, D. Vasileska, S. M. Goodnick
Quantum-confined semiconductor structures are the cornerstone of modern-day electronics. Spatial confinement in these structures leads to formation of discrete low-dimensional subbands. At room temperature, carriers transfer among different states due to efficient scattering with phonons, charged impurities, surface roughness and other electrons, so transpor
Zhexian Wang, Eric J. Heller
In a quantum revival, a localized wavepacket re-forms or "revives" into a compact reincarnation of itself long after it has spread in an unruly fashion over a region restricted only by the potential energy. This is a purely quantum phenomenon, which has no classical analog. Quantum revival, and Anderson localization, are members of a small class of s
Thomas Duquesne
In 1981, J. Hawkes conjectured the exact form of the Hausdorff gauge function for the boundary of supercritical Galton-Watson trees under a certain assumption on the tail at the infinity of the total mass of the branching measure. Hawkes's conjecture has been proved by T. Watanabe in 2007 as well as other other precise results on fractal properties of th
Thierry Champion, Luigi De Pascale, Chloé Jimenez
The so-called eigenvalues and eigenfunctions of the infinite Laplacian $Δ_\infty$ are defined through an asymptotic study of that of the usual $p$-Laplacian $Δ_p$, this brings to a characterization via a non-linear eigenvalue problem for a PDE satisfied in the viscosity sense. In this paper, we obtain an other characterization of the first eigenvalue via a p
M. Fromm, Ph. de Forcrand
The strong coupling limit ($\beta_{gauge}=0$) of lattice QCD with staggered fermions enjoys the same non-perturbative properties as continuum QCD, namely confinement and chiral symmetry breaking. In contrast to the situation at weak coupling, the sign problem which appears at finite density can be brought under control for a determination of the full (mu,T)
Vladislav Popkov, Mario Salerno, Gunter M. Schutz
We consider the asymmetric simple exclusion process (ASEP) on a semi-infinite chain which is coupled at the end to a reservoir with a particle density that changes periodically in time. It is shown that the density profile assumes a time-periodic sawtooth-like shape. This shape does not depend on initial conditions and is found analytically in the hydrodynam
Niklas Eriksen, Ragnar Freij, Johan Wastlund
We enumerate derangements with descents in prescribed positions. A generating function was given by Guo-Niu Han and Guoce Xin in 2007. We give a combinatorial proof of this result, and derive several explicit formulas. To this end, we consider fixed point $λ$-coloured permutations, which are easily enumerated. Several formulae regarding these numbers are giv
Effect of doping-- and field--induced charge carrier density on the electron transport in nanocrystalline ZnO
cond-mat.mtrl-sciMaria S Hammer, Daniel Rauh, Carsten Deibel, Vladimir Dyakonov
Charge transport properties of thin films of sol--gel processed undoped and Al-doped zinc oxide nanoparticles with variable doping level between 0.8 at% and 10 at% were investigated. The X-ray diffraction studies revealed a decrease of the average crystallite sizes in highly doped samples. We provide estimates of the conductivity and the resulting charge car
Petia Vlahovska, Ruben Serral Gracia, Said Aranda, Rumiana Dimova
We develop an analytical theory to explain the experimentally-observed morphological transitions of giant vesicles induced by AC electric fields (1). The model treats the inner and suspending media as lossy dielectrics, while the membrane as an ion-impermeable flexible incompressible-fluid sheet. The vesicle shape is obtained by balancing electric, hydrodyna
Symmetry-Breaking and Symmetry-Restoring Dynamics of a Mixture of Bose-Einstein Condensates in a Double Well
quant-phIndubala I Satija, Philip Naudus, Radha Balakrishnan, Jeffrey Heward
We study the coherent nonlinear tunneling dynamics of a binary mixture of Bose-Einstein condensates in a double-well potential. We demonstrate the existence of a new type of mode associated with the "swapping" of the two species in the two wells of the potential. In contrast to the symmetry breaking macroscopic quantum self-trapping (MQST) solutions,
Identifying Decaying Supermassive Black Hole Binaries from their Variable Electromagnetic Emission
astro-phZoltán Haiman, Bence Kocsis, Kristen Menou, Zoltán Lippai
Supermassive black hole binaries (SMBHBs) with masses in the range 10^4-10^7 M_sun/(1+z), produced in galaxy mergers, are thought to complete their coalescence due to the emission of gravitational waves (GWs). The anticipated detection of the GWs by the LISA will constitute a milestone for fundamental physics and astrophysics. While the GW signatures themsel
Interplay of the emission from thermal and direct sources in relativistic heavy ion collisions
nucl-thPiotr Bozek
The separation of the source created in ultrarelativistic heavy-ion collisions into a thermalized dense core and an outer mantle consisting of independent nucleon-nucleon collisions is discussed. Evidence for such a two component picture is found in transverse mass spectra of kaon, protons and antiprotons produced in Au-Au collisions at 200GeV. Estimates of
Didier Dacunha-Castelle, Lisandro J. Fermín
We study the aggregation of AR processes and generalized Ornstein-Uhlenbeck (OU) processes. Mixture of spectral densities with random poles are the main tool. In this context, we apply our results for the aggregation of doubly stochastic interactives processes, see Dacunha-Castelle and Fermin (2006). Thus, we study the relationship between aggregation of aut
Thomas Fischbacher
A novel method is presented which employs advanced numerical techniques used in the engineering sciences to find and study the properties of nontrivial vacua of gauged extended supergravity models. While this method only produces approximate numerical data rather than analytic results, it overcomes the previous limitation of only being able to find vacua wit
Kaustuv C. Chaudhuri, Damien Doligez, Leslie Lamport, Stephan Merz
We describe an extension to the TLA+ specification language with constructs for writing proofs and a proof environment, called the Proof Manager (PM), to checks those proofs. The language and the PM support the incremental development and checking of hierarchically structured proofs. The PM translates a proof into a set of independent proof obligations and c
J. H. Cole, L. C. L. Hollenberg
The use of qubits as sensitive magnetometers has been studied theoretically and recent demonstrated experimentally. In this paper we propose a generalisation of this concept, where a scanning two-state quantum system is used to probe the subtle effects of decoherence (as well as its surrounding electromagnetic environment). Mapping both the Hamiltonian and d
J. M. A. Broomfield, P. D. Stevenson
The mass distributions for giant dipole resonances in 32S and 132Sn decaying through particle emission and for deep-inelastic collisions between 16O nuclei have been investigated by implementing the Balian-Veneroni variational technique based upon a three-dimensional time-dependent Hartree-Fock code with realistic Skyrme interactions. The mass distributions
Karel Kolar
The choice of a factorization scheme suitable for Monte Carlo simulations of NLO initial state parton showers is discussed in this contribution.
The genesis of morphologies in extended radio sources: X-shapes, off-axis distortions and giant radio sources
astro-phLakshmi Saripalli, Ravi Subrahmanyan
We examine relationships between the morphology in double radio sources and the radio-optical position angle offset--the relative orientation of the radio axis with respect to the major axis of the host galaxy. The study was done for a representative sample of radio sources: the nearby (redshift z < 0.5) 3CRR sources, and separately for samples of giant radi
M. Jardine, J. -F. Donati, S. G. Gregory
It has been known for some time now that rapidly-rotating solar-like stars possess the stellar equivalent of solar prominences. These may be three orders of magnitude more massive than their solar counterparts, and their ejection from the star may form a significant contribution to the loss of angular momentum and mass in the stellar wind. In addition, their
M. Jardine, J. -F. Donati
The coronal structure of main sequence stars continues to puzzle us. While the solar corona is relatively well understood, it has become clear that even stars of the same mass as the Sun can display very non-solar coronal behaviour, particularly if they are rapid rotators or in a binary system. At masses greater than and also less than that of the Sun, the n
Chenggang Tao, Qiang Liu, Blake C. Riddick, William G. Cullen
Low-dimensional boundaries between phases and domains in organic thin films are important in charge transport and recombination. Here, fluctuations of interfacial boundaries in an organic thin film, acridine-9-carboxylic acid (ACA) on Ag(111), have been visualized in real time, and measured quantitatively, using Scanning Tunneling Microscopy. The boundaries
Slow conductance relaxations; Distinguishing the Electron Glass from extrinsic mechanisms
cond-mat.dis-nnZ. Ovadyahu
Slow conductance relaxations are observable in a many condensed matter systems. These are sometimes described as manifestations of a glassy phase. The underlying mechanisms responsible for the slow dynamics are often due to structural changes which modify the potential landscape experienced by the charge-carriers and thus are reflected in the conductance. Sl
Fabien Chirot, Pierre Feiden, Sébastien Zamith, Pierre Labastie
A novel experimental scheme has been developed in order to measure the heat capacity of mass selected clusters. It is based on controlled sticking of atoms on clusters. This allows one to construct the caloric curve, thus determining the melting temperature and the latent heat of fusion in the case of first-order phase transitions. This method is model-free.
Yan Dolinsky, Yuri Kifer
We show that the shortfall risk of binomial approximations of game (Israeli) options converges to the shortfall risk in the corresponding Black--Scholes market considering Lipschitz continuous path-dependent payoffs for both discrete- and continuous-time cases. These results are new also for usual American style options. The paper continues and extends the s
Measurement of the magnetic field inside the holes of a drilled bulk high-Tc superconductor
cond-mat.supr-conGregory P Lousberg, Jean-Francois Fagnard, Jacques G Noudem, Marcel Ausloos
We use macroscopic holes drilled in a bulk YBCO superconductor to probe its magnetic properties in the volume of the sample. The sample is subjected to an AC magnetic flux with a density ranging from 30mT to 130mT and the flux in the superconductor is probed by miniature coils inserted in the holes. In a given hole, three different penetration regimes can be
Wave patterns generated by a supersonic moving body in a binary Bose-Einstein condensate
cond-mat.otherYu. G. Gladush, A. M. Kamchatnov, Z. Shi, P. G. Kevrekidis
Generation of wave structures by a two-dimensional object (laser beam) moving in a two-dimensional two-component Bose-Einstein condensate with a velocity greater than both sound velocities of the mixture is studied by means of analytical methods and systematic simulations of the coupled Gross-Pitaevskii equations. The wave pattern features three regions sepa
Bond analysis of cobalt and iron based skutterudites: elongated lanthanum bonds in LaFe4P12
cond-mat.mtrl-sciEspen Flage-Larsen, Ole Martin Loevvik, Oeystein Prytz, Johan Taftoe
Motivated by the possibility of further improving the thermoelectric properties of skutterudites we investigate charge transfer and bonding in this class of materials using density functional calculations. Results for the CoP3, CoSb3, LaFe4P12 and the hypothetical FeP3 compounds are presented using the procrystal as the non-binding reference. Spherical integ
Tobias Goecke, Christian S. Fischer, Richard Williams
We investigate the impact of finite volume effects on the critical number of flavours, N_f^c, for chiral symmetry restoration in QED3. To this end we solve a set of coupled Dyson-Schwinger equations on a torus. For order parameters such as the anomalous dimension of the fermion wave function or the chiral condensate we find substantial evidence for a large d
Stanislav Zivny, David A. Cohen, Peter G. Jeavons
It has previously been an open problem whether all Boolean submodular functions can be decomposed into a sum of binary submodular functions over a possibly larger set of variables. This problem has been considered within several different contexts in computer science, including computer vision, artificial intelligence, and pseudo-Boolean optimisation. Using
Semiclassical Theory for Decay and Fragmentation Processes in Chaotic Quantum Systems
cond-mat.mes-hallMartha Gutierrez, Daniel Waltner, Jack Kuipers, Klaus Richter
We consider quantum decay and photofragmentation processes in open chaotic systems in the semiclassical limit. We devise a semiclassical approach which allows us to consistently calculate quantum corrections to the classical decay to high order in an expansion in the inverse Heisenberg time. We present results for systems with and without time reversal symme
Soumyottam Chatterjee, Shamik Ghosh
This note explores the relation between the boxicity of undirected graphs and the Ferrers dimension of digraphs.
D. O. Krivenkov, D. A. Artemenkov, V. Bradnova, M. Haiduc
\indent First results of the exposure of nuclear track emulsions in a secondary beam enriched by $^9$C nuclei at energy of 1.2 A GeV are described. The presented statistics corresponds to the most peripheral $^9$C interactions. For the first time a dissociation $^9$C $\to3^3$He not accompanied by target fragments and mesons is identified.\par
Colin Wilmott, Peter Wild
We give a quantum gate construction - composed entirely from incidents of the CNOT gate - that generalises the qubit SWAP gate to higher dimensions. This new construction is more regular than and is an improvement on the WilNOT quantum gate construction.
Ivan Varzinczak
Like any other logical theory, domain descriptions in reasoning about actions may evolve, and thus need revision methods to adequately accommodate new information about the behavior of actions. The present work is about changing action domain descriptions in propositional dynamic logic. Its contribution is threefold: first we revisit the semantics of action
High-pressure growth of fluorine-free SmFeAsO$_{1-x}$ superconducting single crystals
cond-mat.supr-conHyun-Sook Lee, Jae-Hyun Park, Jae-Yeap Lee, Nak-Heon Sung
Superconducting single crystals of SmFeAsO$_{1-x}$ without fluorine doping were grown at a pressure of 3.3 GPa and a temperature of 1350-1450 $^\circ$C by using the self-flux method. Plate-like single crystals of a few-150 $μ$m in their lateral size were obtained. Single crystals showed the superconducting transition at about 53.5 K with a narrow transition
Angelo Bassi, Detlef Duerr
Stochastic differential equations in Hilbert space as random nonlinear modified Schroedinger equations have achieved great attention in recent years; of particular interest is the long time behavior of their solutions. In this note we discuss the long time behavior of the solutions of the stochastic differential equation describing the time evolution of a fr
Dmitriy Bilyk
In [13], K. Roth showed that the expected value of the $L^2$ discrepancy of the cyclic shifts of the $N$ point van der Corput set is bounded by a constant multiple of $\sqrt{\log N}$, thus guaranteeing the existence of a shift with asymptotically minimal $L^2$ discrepancy, [11]. In the present paper, we construct a specific example of such a shift.
Valerio Faraoni
By using the equivalence between metric and Palatini f(R) (or "modified") gravities with omega=0, -3/2 Brans-Dicke theories, it is shown that the Ehlers-Geren-Sachs theorem of general relativity is extended to modified gravity. In the case of metric f(R) gravity previously studied, this agrees with previous literature.
S. L. Liang, Aigen Li
We explore the extinction properties of the dust in the distant universe through the afterglows of high-redshifted GRBs based on the "Drude" model which, unlike previous studies, does not require a prior assumption of template extinction laws. We select GRB070802 at z~2.45 (which shows clear evidence for the 2175Åextinction bump) and GRB050904 at z~6
Oscar Fernandez-Ramos, Philippe Gimenez
Consider an ideal $I\subset K[x_1,..., x_n]$, with $K$ an arbitrary field, generated by monomials of degree two. Assuming that $I$ does not have a linear resolution, we determine the step $s$ of the minimal graded free resolution of $I$ where nonlinear syzygies first appear, we show that at this step of the resolution nonlinear syzygies are concentrated in d
On optimality of the barrier strategy in de Finetti's dividend problem for spectrally negative Lévy processes
math.PRR. L. Loeffen
We consider the classical optimal dividend control problem which was proposed by de Finetti [Trans. XVth Internat. Congress Actuaries 2 (1957) 433--443]. Recently Avram, Palmowski and Pistorius [Ann. Appl. Probab. 17 (2007) 156--180] studied the case when the risk process is modeled by a general spectrally negative Lévy process. We draw upon their results an
L. Pentericci, A. Grazian, A. Fontana, M. Castellano
We have analyzed a sample of LBGs from z =3.5 to z=6 selected from the GOODS-S field as B,V and i-dropouts, and with spectroscopic observations showing that they have the Lyalpha line in emission. Our main aim is to investigate their physical properties and their dependence on the emission line characteristics, to shed light on the relation between galaxies
Paolo Oresta, Roberto Verzicco, Detlef Lohse, Andrea Prosperetti
The heat transfer mechanism in Rayleigh-Benard convection in a liquid with a mean temperature close to its boiling point is studied through numerical simulations with point-like vapor bubbles, which are allowed to grow or shrink through evaporation and condensation and which act back on the flow both thermally and mechanically. It is shown that the effect of
David Arroyo, Gonzalo Alvarez, Veronica Fernandez
Chaotic cryptography is based on the properties of chaos as source of entropy. Many different schemes have been proposed to take advantage of those properties and to design new strategies to encrypt information. However, the right and efficient use of chaos in the context of cryptography requires a thorough knowledge about the dynamics of the selected chaoti
D. Kaneko, K. Yamagishi, A. Tsukada, T. Manabe
We report the synthesis of infinite-layer LaNiO2 thin films by metal organic decomposition. Our work is aimed to synthesize perovskite-like oxides with 3d9 electronic configuration, which is common to high-Tc copper oxides. The 3d9 configuration is very rare in oxides other than cuprates. Ni1+ oxides, even though Ni1+ is an unusual oxidation state, may be on
Osamu Matsumoto, Aya Utsuki, Akio Tsukada, Hideki Yamamoto
We investigated the generic phase diagram of the electron doped superconductor, Nd2-xCexCuO4, using films prepared by metal organic decomposition. After careful oxygen reduction treatment to remove interstitial Oap atoms, we found that the Tc increases monotonically from 24 K to 29 K with decreasing x from 0.15 to 0.00, demonstrating a quite different phase
P. Benndorf, M. T. Gamer, P. W. Roesky, G. Eickerling
The amido rhenium trioxides of composition (iPr2N)ReO3, (iPrCyN)ReO3 and (Cy2N)ReO3 (Cy = cyclohexyl) were synthesized in a one pot reaction starting from Re2O7, Me3SiCl and the corresponding amines (iPr)2NH, (iPr)(Cy)NH, and (Cy)2NH, respectively. In the solid state the amido ligands of all three complexes are asymmetrically coordinated to the ReO3 core all
A. M. Selvam
The frequency of occurrence of prime numbers at unit number spacing intervals exhibits selfsimilar fractal fluctuations concomitant with inverse power law form for power spectrum generic to dynamical systems in nature such as fluid flows, stock market fluctuations, population dynamics, etc. The physics of long-range correlations exhibited by fractals is not