June 2009 arXiv papers — page 7
Showing 601–700 of 5,471 papers
Accretion flow behaviour during the evolution of the Quasi Periodic Oscillation Frequency of XTE J1550-564 in 1998 outburst
astro-ph.HESandip K. Chakrabarti, Broja G. Dutta, P. S. Pal
Low and intermediate frequency quasi-periodic oscillations (QPOs) are thought to be due to oscillations of Comptonizing regions or hot regions embedded in Keplerian discs. Observational evidence of evolutions of QPOs would therefore be very important as they throw lights on the dynamics of the hotter region. Our aim is to find systems in which there is a wel
A. I. Mamadjanov, A. A. Hakimov, S. R. Tojiev
The phase shift a neutron interferometer caused by the gravitational field and the rotation of the earth is derived in a unified way from the standpoint of general relativity. General relativistic quantum interference effects in the slowly rotating braneworld as the Sagnac effect and phase shift effect of interfering particle in neutron interferometer are co
D. A. Kulikov, R. S. Tutik
The new potential model for pionic hydrogen, constructed with the employment of the two-body relativistic equation, is offered. The relativistic equation, based on the extension of the $SL(2,C)$ group to the $Sp(4,C)$ one, describes the effect of the proton spin and anomalous magnetic moment in accordance with the results of the quantum electrodynamics. With
Mauro Costantini
Let G be a simple algebraic group over an algebraically closed field k of bad characteristic. We classify the spherical unipotent conjugacy classes of G. We also show that if the characteristic of k is 2, then the fixed point subgroup of every involutorial automorphism (involution) of G is a spherical subgroup of G.
Prof. Dhananjay R. Kalbande, Dr. G. T. Thampi, Mr. Manish Singh
A computer network can be attacked in a number of ways. The security-related threats have become not only numerous but also diverse and they may also come in the form of blended attacks. It becomes difficult for any security system to block all types of attacks. This gives rise to the need of an incidence handling capability which is necessary for rapidly de
Vadim Kuzmin
This is a kind of essay dedicated to Lev Borisovich Okun. I would like to ask some questions which I can not answer. However I suspect I know how to answer them. Questions are as follows: 1. Particle identity. 2. Information storage. 3. Information read-out at the speed higher than that of light.
Debabrata Pal, Amitava Choudhuri, B Talukdar
We show that the complex modified KdV (cmKdV) equation and generalized nonlinear Schrödinger (GNLS) equation belong to the Ablowitz, Kaup, Newell and Segur or so-called AKNS hierarchy. Both equations do not follow from the action principle and are nonintegrable. By introducing some auxiliary fields we obtain the variational principle for them and study their
M. Zh. Nikoghosyan, Zh. G. Nikoghosyan
Every 4-connected graph $G$ with minimum degree $δ$ and connectivity $κ$ either contains a cycle of length at least $4δ-κ-4$ or every longest cycle in $G$ is a dominating cycle.
Mancho Manev
Almost hypercomplex manifolds with Hermitian and Norden metrics and more specially the corresponding quaternionic Kaehler manifolds are considered. Some necessary and sufficient conditions the investigated manifolds be isotropic hyper-Kaehlerian and flat are found. It is proved that the quaternionic Kaehler manifolds with the considered metric structure are
Leah Epstein, Asaf Levin
Following the work of Anily et al., we consider a variant of bin packing, called "bin packing with general cost structures" (GCBP) and design an asymptotic fully polynomial time approximation scheme (AFPTAS) for this problem. In the classic bin packing problem, a set of one-dimensional items is to be assigned to subsets of total size at most 1, that
Leah Epstein, Asaf Levin
We consider two well-known natural variants of bin packing, and show that these packing problems admit asymptotic fully polynomial time approximation schemes (AFPTAS). In bin packing problems, a set of one-dimensional items of size at most 1 is to be assigned (packed) to subsets of sum at most 1 (bins). It has been known for a while that the most basic probl
G. Belanger, F. Boudjema, A. Pukhov, R. K. Singh
Using a Markov chain Monte Carlo approach, we find the allowed parameter space of a MSSM model with seven free parameters. In this model universality conditions at the GUT scale are imposed on the gaugino sector. We require in particular that the relic density of dark matter saturates the value extracted from cosmological measurements assuming a standard cos
Long-Fei Gan, Ming-Qiu Huang
We study the heavy quark effective theory prediction for semileptonic $B$ decays into an orbital excited $F$-wave charmed doublet, the ($2^{+}$, $3^{+}$) states ($D^{*'}_{2}$, $D_{3}$), at the leading order of heavy quark expansion. The corresponding universal form factor is estimated by using the QCD sum rule method. The decay rates we predict are $Γ_{B
Chendong Li
The hardness of finite domain Constraint Satisfaction Problems (CSPs) is a very important research area in Constraint Programming (CP) community. However, this problem has not yet attracted much attention from the researchers in the association rule mining community. As a popular data mining technique, association rule mining has an extremely wide applicatio
Ahmed Ben Jmaa, Walid Mahdi, Yousra Ben Jemaa, Abdelmajid Ben Hamadou
We present in this paper a new approach for hand gesture analysis that allows digit recognition. The analysis is based on extracting a set of features from a hand image and then combining them by using an induction graph. The most important features we extract from each image are the fingers locations, their heights and the distance between each pair of fing
A Novel Two-Stage Dynamic Decision Support based Optimal Threat Evaluation and Defensive Resource Scheduling Algorithm for Multi Air-borne threats
cs.AIHuma Naeem, Asif Masood, Mukhtar Hussain, Shoab A. Khan
This paper presents a novel two-stage flexible dynamic decision support based optimal threat evaluation and defensive resource scheduling algorithm for multi-target air-borne threats. The algorithm provides flexibility and optimality by swapping between two objective functions, i.e. the preferential and subtractive defense strategies as and when required. To
Lucian A. Constantin
Commonly used semilocal density functional approximations for the exchange-correlation energy fail badly when the true two dimensional limit is approached. We show, using a quasi-two-dimensional uniform electron gas in the infinite barrier model, that the semilocal level can correctly recover the exchange-correlation energy of the two-dimensional uniform ele
Matthias Bartelmann
For a few years now, cosmology has a standard model. By this term, we mean a consistent theoretical background which is at the same time simple and broad enough to offer coherent explanations for the vast majority of cosmological phenomena. This review will briefly summarise the cosmological model, then proceed to discuss what we know from observations about
Kinetic energy density functionals from the Airy gas, with an application to the atomization kinetic energies of molecules
cond-mat.mtrl-sciLucian A. Constantin, Adrienn Ruzsinszky
We construct and study several semilocal density functional approximations for the positive Kohn-Sham kinetic energy density. These functionals fit the kinetic energy density of the Airy gas and they can be accurate for integrated kinetic energies of atoms, molecules, jellium clusters and jellium surfaces. We find that these functionals are the most accurate
Anshika Pal, Deepak Singh Tomar, S. C. Shrivastava
A focused crawler traverses the web selecting out relevant pages to a predefined topic and neglecting those out of concern. While surfing the internet it is difficult to deal with irrelevant pages and to predict which links lead to quality pages. In this paper a technique of effective focused crawling is implemented to improve the quality of web navigation.
Lucian A. Constantin, Adrienn Ruzsinszky, John P. Perdew
In recent work, generalized gradient approximations (GGA's) have been constructed from the energy density of the Airy gas for exchange but not for correlation. We report the random phase approximation (RPA) conventional correlation energy density of the Airy gas, the simplest edge electron gas, in which the auxiliary noninteracting electrons experience a
Ram Kumar Singh, Prof. T. Ramajujam
The exponential growth of Internet traffic has made public servers increasingly vulnerable to unauthorized accesses and intrusions. In addition to maintaining low latency for the client, filtering unauthorized accesses has become one of the major concerns of a server maintainer. This implementation of an Intrusion Detection System distinguishes between the t
O. Vaduvescu, L. Curelaru, M. Birlan, G. Bocsa
Besides new observations, mining old photographic plates and CCD image archives represents an opportunity to recover and secure newly discovered asteroids, also to improve the orbits of Near Earth Asteroids (NEAs), Potentially Hazardous Asteroids (PHAs) and Virtual Impactors (VIs). These are the main research aims of the EURONEAR network. As stated by the IA
Workhorse Semilocal Density Functional for Condensed Matter Physics and Quantum Chemistry
cond-mat.mtrl-sciJohn P. Perdew, Adrienn Ruzsinszky, Gabor I. Csonka, Lucian A. Constantin
Semilocal density functionals for the exchange-correlation energy are needed for large electronic systems. The Tao-Perdew-Staroverov-Scuseria (TPSS) meta-generalized gradient approximation (meta-GGA) is semilocal and usefully accurate, but predicts too-long lattice constants. Recent "GGA's for solids" yield good lattice constants but poor atomiza
Isoprenaline increases Excursive Restitution Slope in the Conscious Rabbit with Ischaemic Heart Failure
q-bio.TOTomofumi Kimotsuki, Noriko Niwa, Martin N. Hicks, Michael Dunne
Background: An increased QT/RR slope is hypothesized to be predictive of sudden cardiac death after myocardial infarction. Previous studies have shown that beta-adrenergic stimulation increases QT/RR slope, but the effects of beta-adrenergic stimulation on QT/RR slope in heart failure are unknown. Methods: New Zealand White rabbits underwent coronary ligatio
N. Flagey, A. Noriega-Crespo, F. Boulanger, S. J. Carey
We present Spitzer images of the Taurus Complex (TC) and take advantage of the sensitivity and spatial resolution of the observations to characterize the diffuse IR emission across the cloud. This work highlights evidence of dust evolution within the translucent sections of the archetype reference for studies of quiescent molecular clouds. We combine Spitzer
R. C. Pooser, A. M. Marino, V. Boyer, K. M. Jones
We present an experimental realization of a low-noise, phase-insensitive optical amplifier using a four-wave mixing interaction in hot Rb vapor. Performance near the quantum limit for a range of amplifier gains, including near unity, can be achieved. Such low-noise amplifiers are essential for so-called quantum cloning machines and are useful in quantum info
Chia-Min Lin
In this paper, we show that in the framework of chaotic braneworld inflation, after preheating, the remaining oscillating inflaton field can play the role of dark matter with the observed level. Augmented by a non-zero effective cosmological constant $Λ_4$ on the brane, triple unification of inflation, dark matter and dark energy by a single field is realize
K. -I. Nishikawa, J. Niemiec, M. Medvedev, B. Zhang
Using our new 3-D relativistic electromagnetic particle (REMP) code parallelized with MPI, we investigated long-term particle acceleration associated with a relativistic electron-positron jet propagating in an unmagnetized ambient electron-positron plasma. The simulations were performed using a much longer simulation system than our previous simulations in o
Ming-Sheng Shang, Zi-Ke Zhang, Tao Zhou, Yi-Cheng Zhang
Collaborative tags are playing more and more important role for the organization of information systems. In this paper, we study a personalized recommendation model making use of the ternary relations among users, objects and tags. We propose a measure of user similarity based on his preference and tagging information. Two kinds of similarities between users
Victor Pavlunin
I discuss a method to model the instrumental response of the CMS and ATLAS detectors at high transverse missing energies to dominant standard model V+jets backgrounds, where V is a Z, gamma or W, using multi-jet QCD events. The method is developed for new physics searches in early data at the Large Hadron Collider (LHC) with minimal recourse to simulation.
Linda M. Carpenter, Michael Dine, Guido Festuccia, Lorenzo Ubaldi
In supersymmetric theories, the presence of axions usually implies the existence of a non-compact, (pseudo)moduli space. In gauge mediated models, the axion would seem a particularly promising dark matter candidate. The cosmology of the moduli then constrains the gravitino mass and the axion decay constant; the former can't be much below 10 MeV; the latt
Aaron W. Brown
We establish two results under which the topology of a hyperbolic set constrains ambient dynamics. First if a set is a compact, transitive, expanding hyperbolic attractor of codimension 1 for some diffeomorphism, then it is a union of transitive, expanding attractors (or contracting repellers) of codimension 1 for any diffeomorphism such that it is hyperboli
M. L. Trouwborst, E. H. Huisman, S. J. van der Molen, B. J. van Wees
Current-voltage characteristics of H2-Au molecular junctions exhibit intriguing steps around a characteristic voltage of 40 mV. Surprisingly, we find that a hysteresis is connected to these steps with a typical time scale > 10 ms. This time constant scales linearly with the power dissipated in the junction beyond an ofset power P_s = IV_s. We propose that th
Christopher Eling, Yaron Oz
We use the membrane paradigm to analyze the horizon dynamics of a uniformly boosted black brane in a (d+2)-dimensional asymptotically Anti-de-Sitter space-time and a Rindler acceleration horizon in (d+2)-dimensional Minkowski space-time. We show that in these cases the horizon dynamics is governed by the relativistic CFT hydrodynamics equations. The fluid ve
Exchange coupling in silicon quantum dots: Theoretical considerations for quantum computation
cond-mat.mes-hallQiuzi Li, Lukasz Cywinski, Dimitrie Culcer, Xuedong Hu
We study exchange coupling in Si double quantum dots, which have been proposed as suitable candidates for spin qubits due to their long spin coherence times. We discuss in detail two alternative schemes which have been proposed for implementing spin qubits in quantum dots. One scheme uses spin states in a single dot and the interdot exchange coupling control
Adam Clay
We show that the restriction of the Dehornoy ordering to an appropriate free subgroup of the three-strand braid group defines a left ordering of the free group on k generators, k>1, that has no convex subgroups.
Kai Yi
We report the recent evidence for a new narrow structure, Y(4140), decaying to the $J/\psi \phi$ final state, in exclusive $B^+\to J/\psi\phi K^+$ decays in a data sample corresponding to an integrated luminosity of 2.7 \ifb collected at the CDF II detector. This narrow structure with its mass well above open charm pairs is unlikely to be a candidate for a c
K. V. Rashmi, Nihar B. Shah, P. Vijay Kumar, Kannan Ramchandran
Erasure coding techniques are used to increase the reliability of distributed storage systems while minimizing storage overhead. Also of interest is minimization of the bandwidth required to repair the system following a node failure. In a recent paper, Wu et al. characterize the tradeoff between the repair bandwidth and the amount of data stored per node. T
Transient effects and reconstruction of the energy spectra in the time evolution of transmitted Gaussian wave packets
quant-phSergio Cordero, Gaston Garcia-Calderon
We derive an exact analytical solution to the time-dependent Schrödinger equation for transmission of a Gaussian wave packet through an arbitrary potential of finite range. We consider the situation where the initial Gaussian wave packet is sufficiently broad in momentum space to guarantee that the resonance structure of the system is included in the dynamic
Bin Cheng, Chunjing Xie
We prove global existence and asymptotic behavior of classical solutions for two dimensional inviscid Rotating Shallow Water system with small initial data subject to the zero-relative-vorticity constraint. One of the key steps is a reformulation of the problem into a symmetric quasilinear Klein-Gordon system, for which the global existence of classical solu
J. Alexandre, N. E. Mavromatos
We consider a time-dependent bosonic string in graviton, dilaton and tachyon backgrounds, for which it was already shown that conformal invariance is respected to all orders in alpha' and in any space-time dimension. Assuming that the tachyon is off-shell, we show in this note that the specific time-homogeneity of the corresponding space time effective actio
L. Isaev, G. Ortiz, J. Dukelsky
We address the physical mechanism responsible for the emergence of magnetization plateaux in the Shastry-Sutherland model. By using a hierarchical mean-field approach we demonstrate that a plateau is stabilized in a certain {\it spin pattern}, satisfying {\it local} commensurability conditions derived from our formalism. Our results provide evidence in favor
A. Y. Shiekh
It may be possible to extend the Grover search algorithm by taking a divide and conquer approach using auxiliary solutions to achieve an exponential speed-up.
Paul Romatschke
Fluid dynamics corresponds to the dynamics of a substance in the long wavelength limit. Writing down all terms in a gradient (long wavelength) expansion up to second order for a relativistic system at vanishing charge density, one obtains the most general (causal) equations of motion for a fluid in the presence of shear and bulk viscosity, as well as the str
Georgy P Karev, Artem S Novozhilov, Faina S Berezovskaya
Selection systems and the corresponding replicator equations model the evolution of replicators with a high level of abstraction. In this paper we apply novel methods of analysis of selection systems to the replicator equations. To be suitable for the suggested algorithm the interaction matrix of the replicator equation should be transformed; in particular t
Lingzhen Guo, Zhigang Zheng, Xin-Qi Li
We investigate the nonlinear dynamics of a mesoscopic driven Duffing oscillator in a quantum regime. In terms of Wigner function, we identify the nature of state near the bifurcation point, and analyze the transient process which reveals two distinct stages of quenching and escape. The rate process in the escape stage allows us to extract the transition rate
Seeking the Loop Quantum Gravity Barbero-Immirzi Parameter and Field in 4D, $\cal N$ = 1 Supergravity
hep-thS. James Gates, Sergei V. Ketov, Nicolas Yunes
We embed the Loop Quantum Gravity Barbero-Immirzi parameter and field within an action describing 4D, $\cal N$ = 1 supergravity and thus within a Low Energy Effective Action of Superstring/M-Theory. We use the fully gauge-covariant description of supergravity in (curved) superspace. The gravitational constant is replaced with the vacuum expectation value of
Kinematic deprojection and mass inversion of spherical systems of known velocity anisotropy
astro-ph.COGary A. Mamon, Gwenael Boué
Traditionally, the mass / velocity anisotropy degeneracy (MAD) inherent in the spherical, stationary, non-streaming Jeans equation has been handled by assuming a mass profile and fitting models to the observed kinematical data. Here, the opposite approach is considered: the equation of anisotropic kinematic projection is inverted for known arbitrary anisotro
Graphene Dirac fermions in one-dimensional inhomogeneous field profiles: Transforming magnetic to electric field
cond-mat.mes-hallLiang Zheng Tan, Cheol-Hwan Park, Steven G. Louie
We show that the low-energy electronic structure of graphene under a one-dimensional inhomogeneous magnetic field can be mapped into that of graphene under an electric field or vice versa. As a direct application of this transformation, we find that the carrier velocity in graphene is isotropically reduced under magnetic fields periodic along one direction w
Philipp Hieronymi
Let D\subseteq \mathbb{R} be closed and discrete and f:D^n \to \mathbb{R} be such that f(D^n) is somewhere dense. We show that (\mathbb{R},+,\cdot,f) defines the set of integers. As an application, we get that for every a,b \in \mathbb{R} with \log_{a}(b)\notin \mathbb{Q}, the real field expanded by the two cyclic multiplicative subgroups generated by a and
T. Huege
In small-scale experiments such as CODALEMA and LOPES, radio detection of cosmic rays has demonstrated its potential as a technique for cosmic ray measurements up to the highest energies. Radio detection promises measurements with high duty-cycle, allows a direction reconstruction with very good angular resolution, and provides complementary information on e
Suvrit Sra
We make a trivial modification to the elegant analysis of Garg and Khandekar (\emph{Gradient Descent with Sparsification} ICML 2009) that replaces the standard Restricted Isometry Property (RIP), with another RIP-type property (which could be simpler than the RIP, but we are not sure; it could be as hard as the RIP to check, thereby rendering this little wri
The evolving relations between size, mass, surface density, and star formation in 3x10^4 galaxies since z=2
astro-ph.CORik J. Williams, Ryan F. Quadri, Marijn Franx, Pieter van Dokkum
The presence of massive, compact, quiescent galaxies at z>2 presents a major challenge for theoretical models of galaxy formation and evolution. Using one of the deepest large public near-IR surveys to date, we investigate in detail the correlations between star formation and galaxy structural parameters (size, stellar mass, and surface density) from z=2 to
Chandrasekhar Chatterjee, Amitabha Lahiri
We construct, in an SU(2) gauge theory with two adjoint scalars, flux strings with monopoles attached at the ends. One scalar breaks SU(2) to U(1) and produces monopoles, the other then breaks the U(1) and produces strings. Dualizing, we write the theory in terms of effective string variables and show that the flux in the string is exactly saturated by the m
Christoph Hummel
We introduce a family of copulas which are locally piecewise uniform in the interior of the unit cube of any given dimension. Within that family, the simultaneous control of tail dependencies of all projections to faces of the cube is possible and we give an efficient sampling algorithm. The combination of these two properties may be appealing to risk modell
Andreas Karch, Andy O'Bannon, Laurence G. Yaffe
We use the AdS/CFT correspondence to study the thermodynamics of massive N=2 supersymmetric hypermultiplet flavor fields coupled to N=4 supersymmetric SU(Nc) Yang-Mills theory, formulated on curved four-manifolds, in the limits of large Nc and large 't Hooft coupling. The gravitational duals are probe D-branes in global thermal AdS. These D-branes may un
Vitaly Vanchurin
We analyze statistical properties of the separate multipole moments of the CMB temperature maps and find that the distribution tails are slightly non-Gaussian. Moreover, the deviation from Gaussianity peaks sharply at around $l\sim45\pm10$. If the detected non-Gaussianities should be attributed to the remaining foreground contamination from the galactic plan
C. Bogdanos, C. Charmousis, B. Gouteraux, R. Zegers
We find the general solution of the 6-dimensional Einstein-Gauss-Bonnet equations in a large class of space and time-dependent warped geometries. Several distinct families of solutions are found, some of which include black string metrics, space and time-dependent solutions and black holes with exotic horizons. Among these, some are shown to verify a Birkhof
R. V. Mishmash, I. Danshita, Charles W. Clark, L. D. Carr
We present a fully quantum many-body treatment of dark solitons formed by ultracold bosonic atoms in one-dimensional optical lattices. Using time-evolving block decimation to simulate the single-band Bose-Hubbard Hamiltonian, we consider the quantum dynamics of density and phase engineered dark solitons as well as the quantum evolution of mean-field dark sol
R. C. Helling, H. Leschke, W. L. Spitzer
We prove a special case of a conjecture in asymptotic analysis by Harold Widom. More precisely, we establish the leading and next-to-leading term of a semi-classical expansion of the trace of the square of certain integral operators on the Hilbert space $L^2(\R^d)$. As already observed by Gioev and Klich, this implies that the bi-partite entanglement entropy
Extraction of the Pomeron Trajectory from a Global Fit to Exclusive $\rho^0$ Meson Photoproduction Data
hep-exBenno List
Based on data on elastic $\rho^0$ photoproduction from the H1, Omega and ZEUS collaborations, a fit has been performed to extract the value $\alpha_P (t)$ of the pomeron trajectory at fixed values of t from the W dependence of the differential $\gamma p$ cross section $d \sigma_{\gamma p} (W) / d t$. The data used in the fit cover the range of $8.3 \le W \le
Anisotropic bispectrum of curvature perturbations from primordial non-Abelian vector fields
astro-ph.CONicola Bartolo, Emanuela Dimastrogiovanni, Sabino Matarrese, Antonio Riotto
We consider a primordial SU(2) vector multiplet during inflation in models where quantum fluctuations of vector fields are involved in producing the curvature perturbation. Recently, a lot of attention has been paid to models populated by vector fields, given the interesting possibility of generating some level of statistical anisotropy in the cosmological p
W. -R. Hannes, M. Titov
A transfer matrix approach to study ballistic charge transport in few-layer graphene with chiral-symmetric stacking configurations is developed. We demonstrate that the chiral symmetry justifies a non-Abelian gauge transformation at the spectral degeneracy point (zero energy). This transformation proves the equivalence of zero-energy transport properties of
Frank Duzaar, Giuseppe Mingione
We present pointwise gradient bounds for solutions to $p$-Laplacean type non-homogeneous equations employing non-linear Wolff type potentials, and then prove similar bounds, via suitable caloric potentials, for solutions to parabolic equations.
Nicola Gambino, Joachim Kock
We study polynomial functors over locally cartesian closed categories. After setting up the basic theory, we show how polynomial functors assemble into a double category, in fact a framed bicategory. We show that the free monad on a polynomial endofunctor is polynomial. The relationship with operads and other related notions is explored.
Thomas Kahle
We present Binomials, a package for the computer algebra system Macaulay2, which specializes well known algorithms to binomial ideals. These come up frequently in algebraic statistics and commutative algebra, and it is shown that significant speedup of computations like primary decomposition is possible. While central parts of the implemented algorithms go b
Kostas Skenderis, Marika Taylor, Balt C. van Rees
We set up the AdS/CFT correspondence for topologically massive gravity (TMG) in three dimensions. The first step in this procedure is to determine the appropriate fall off conditions at infinity. These cannot be fixed a priori as they depend on the bulk theory under consideration and are derived by solving asymptotically the non-linear field equations. We di
Reanalysis of Data Taken by the CANGAROO 3.8 Meter Imaging Atmospheric Cherenkov Telescope: PSR B1706-44, SN 1006, and Vela
astro-ph.HET. Yoshikoshi, M. Mori, P. G. Edwards, S. Gunji
We have reanalyzed data from observations of PSR B1706-44, SN 1006, and the Vela pulsar region made with the CANGAROO 3.8 m imaging atmospheric Cherenkov telescope between 1993 and 1998 in response to the results reported for these sources by the H.E.S.S. collaboration. In our reanalysis, in which gamma-ray selection criteria have been determined exclusively
C. Wetterich
Quantum mechanics can emerge from classical statistics. A typical quantum system describes an isolated subsystem of a classical statistical ensemble with infinitely many classical states. The state of this subsystem can be characterized by only a few probabilistic observables. Their expectation values define a density matrix if they obey a "purity constr
Erik Bedos, Tron Omland
We show that the full group C$^*$-algebra of $PSL(n, \Z)$ is primitive when $n=2$, and not primitive when $n\geq 3$. Moreover, we show that there exists an uncountable family of pairwise inequivalent, faithful irreducible representations of $C^*(PSL(2,\Z))$.
Luiz F. C. Pereira, C. G. Rocha, A. Latgé, J. N. Coleman
Films composed of nanotube networks have their conductivities regulated by the junction resistances formed between tubes. Conductivity values are enhanced by lower junction resistances but should reach a maximum that is limited by the network morphology. By considering ideal ballistic-like contacts between nanotubes we use the Kubo formalism to calculate the
Strong valence fluctuation in the quantum critical heavy fermion superconductor beta-YbAlB4: A hard x-ray photoemission study
cond-mat.str-elM. Okawa, M. Matsunami, K. Ishizaka, R. Eguchi
Electronic structures of the quantum critical superconductor beta-YbAlB4 and its polymorph alpha-YbAlB4 are investigated by using bulk-sensitive hard x-ray photoemission spectroscopy. From the Yb 3d core level spectra, the values of the Yb valence are estimated to be ~2.73 and ~2.75 for alpha- and beta-YbAlB4, respectively, thus providing clear evidence for
Michael Entov, Leonid Polterovich
Lie quasi-states on a real Lie algebra are functionals which are linear on any abelian subalgebra. We show that on the symplectic Lie algebra of rank at least 3 there is only one continuous non-linear Lie quasi-state (up to a scalar factor, modulo linear functionals). It is related to the asymptotic Maslov index of paths of symplectic matrices.
Steffen Löck, Arnd Bäcker, Roland Ketzmerick, Peter Schlagheck
We derive a prediction of dynamical tunneling rates from regular to chaotic phase-space regions combining the direct regular-to-chaotic tunneling mechanism in the quantum regime with an improved resonance-assisted tunneling theory in the semiclassical regime. We give a qualitative recipe for identifying the relevance of nonlinear resonances in a given $\hbar
Maciej J. Capinski, Piotr Zgliczynski
We consider the elliptic three body problem as a perturbation of the circular problem. We show that for sufficiently small eccentricities of the elliptic problem, and for energies sufficiently close to the energy of the libration point L2, a Cantor set of Lyapounov orbits survives the perturbation. The orbits are perturbed to quasi-periodic invariant tori. W
J. Bouttier, E. Guitter
We consider quadrangulations with a boundary and derive explicit expressions for the generating functions of these maps with either a marked vertex at a prescribed distance from the boundary, or two boundary vertices at a prescribed mutual distance in the map. For large maps, this yields explicit formulas for the bulk-boundary and boundary-boundary correlato
The 3-5 micron Spectrum of NGC 1068 at High Angular Resolution: Distribution of Emission and Absorption Features across the Nuclear Continuum Source
astro-ph.COT. R. Geballe, R. E. Mason, A. Rodríguez-Ardila, D. J. Axon
We report moderate resolution 3-5 micron spectroscopy of the nucleus of NGC 1068 obtained at 0.3 arcsec (20 pc) resolution with the spectrograph slit aligned approximately along the ionization cones of the AGN. The deconvolved FWHM of the nuclear continuum source in this direction is 0.3 arcsec. Four coronal lines of widely different excitations were detecte
Harald Hanche-Olsen, Helge Holden
We show that the Arzela-Ascoli theorem and Kolmogorov compactness theorem both are consequences of a simple lemma on compactness in metric spaces. Their relation to Helly's theorem is discussed. The paper contains a detailed discussion on the historical background of the Kolmogorov compactness theorem.
Discrimination with error margin between two states - Case of general occurrence probabilities -
quant-phH. Sugimoto, T. Hashimoto, M. Horibe, A. Hayashi
We investigate a state discrimination problem which interpolates minimum-error and unambiguous discrimination by introducing a margin for the probability of error. We closely analyze discrimination of two pure states with general occurrence probabilities. The optimal measurements are classified into three types. One of the three types of measurement is optim
Analytical Estimate of Atmospheric Newtonian Noise Generated by Acoustic and Turbulent Phenomena in Laser-Interferometric Gravitational Waves Detectors
gr-qcCarlo Cafaro, S. A. Ali
We present a theoretical estimate of the atmospheric Newtonian noise due to fluctuations of atmospheric mass densities generated by acoustic and turbulent phenomena and we determine the relevance of such noise in the laser-interferometric detection of gravitational waves. First, we consider the gravitational coupling of interferometer test-masses to fluctuat
Ziqing Wang, Ming Li
A transition rate model of cargo transport by $N$ molecular motors is proposed. Under the assumption of steady state, the force-velocity curve of multi-motor system can be derived from the force-velocity curve of single motor. Our work shows, in the case of low load, the velocity of multi-motor system can decrease or increase with increasing motor number, wh
Theory of activated-rate processes under shear with application to shear-induced aggregation of colloids
cond-mat.softAlessio Zaccone, Daniele Gentili, Hua Wu, Massimo Morbidelli
Using a novel approximation scheme within the convective diffusion (two body Smoluchowski) equation framework, we unveil the shear-driven aggregation mechanism at the origin of structure-formation in sheared colloidal systems. The theory, verified against numerics and experiments, explains the induction time followed by explosive (irreversible) rise of visco
G. Bison, N. Castagna, A. Hofer, P. Knowles
We present a multichannel cardiac magnetic field imaging system built in Fribourg from optical double-resonance Cs vapor magnetometers. It consists of 25 individual sensors designed to record magnetic field maps of the beating human heart by simultaneous measurements on a grid of 19 points over the chest. The system is operated as an array of second order gr
Anisur Rahaman, Safia Yasmin, Sahazada Aziz
Chiral Schwinger model with the Faddeevian anomaly is considered. It is found that imposing a chiral constraint this model can be expressed in terms of chiral boson. The model when expressed in terms of chiral boson remains anomalous and the Gauss law of which gives anomalous Poisson brackets between itself. In spite of that a systematic BRST quantization is
Maria Elisabetta Pezzoli, Federico Becca
We study the interplay between electron correlation and disorder in the two-dimensional Hubbard model at half-filling by means of a variational wave function that can interpolate between Anderson and Mott insulators. We give a detailed description of our improved variational state and explain how the physics of the Anderson-Mott transition can be inferred fr
N. M. R. Peres, Ling Yang, Shan-Wen Tsai
We present exact analytical calculations of scanning tunneling currents in locally disordered graphene using a multimode description of the microscope tip. Analytical expressions for the local density of states (LDOS) are given for energies beyond the Dirac cone approximation. We show that the LDOS at the $A$ and $B$ sublattices of graphene are out of phase
Massimiliano Mella, Elena Polastri
Two divisors in $¶^n$ are said to be Cremona equivalent if there is a Cremona modification sending one to the other. We produce infinitely many non equivalent divisorial embeddings of any variety of dimension at most 14. Then we study the special case of plane curves and rational hypersurfaces. For the latter we characterise surfaces Cremona equivalent to a
Sinya Aoki, Hidenori Fukaya
We consider chiral perturbation theory (ChPT) with a non-zero theta term. Due to the CP violating term, the vacuum of chiral fields is shifted to a non-trivial element on the SU(N_f) group manifold. The CP violation also provides mixing of different CP eigenstates, between scalar and pseudoscalar, or vector and axialvector operators. We investigate upto O(th
S. L. W. Midgley, A. J. Ferris, M. K. Olsen
Asymmetric steering is an effect whereby an inseparable bipartite system can be found to be described by either quantum mechanics or local hidden variable theories depending on which one of Alice or Bob makes the required measurements. We show that, even with an inseparable bipartite system, situations can arise where Gaussian measurements on one half are no
Philippe Marie, Jerome Rousseau
This paper is a first step in the study of the recurrence behavior in random dynamical systems and randomly perturbed dynamical systems. In particular we define a concept of quenched and annealed return times for systems generated by the composition of random maps. We moreover prove that for super-polynomially mixing systems, the random recurrence rate is eq
Michel De Lara, Pedro Gajardo, Hector Ramirez Cabrera
Some monospecies age class models, as well as specific multi-species models (with so-called technical interactions), exhibit useful monotonicity properties. This paper deals with discrete time monotone bioeconomics dynamics in the presence of state and control constraints. In practice, these latter "acceptable configurations" represent production and preserv
Yongbeom Kang, Luciana Bianchi, Soo-Chang Rey
We present a comprehensive study of star-forming (SF) regions in the nearest large spiral galaxy M31. We use GALEX far-UV (1344-1786 Å, FUV) and near-UV (1771-2831 Å, NUV) imaging to detect young massive stars and trace the recent star formation across the galaxy. The FUV and NUV flux measurements of the SF regions, combined with ground-based data for estima
SCTE: An open-source Perl framework for testing equipment control and data acquisition
physics.ins-detLuiz C. B. Mostaço-Guidolin, Rafael B. Frigori, Leonid Ruchko, Ricardo M. O. Galvao
SCTE intends to provide a simple, yet powerful, framework for building data acquisition and equipment control systems for experimental Physics, and correlated areas. Via its SCTE::Instrument module, RS-232, USB, and LAN buses are supported, and the intricacies of hardware communication are encapsulated underneath an object oriented abstraction layer. Written
Toke Meier Carlsen, Nadia S. Larsen, Aidan Sims, Sean Vittadello
Let X be a product system over a quasi-lattice ordered group. Under mild hypotheses, we associate to X a C*-algebra which is co-universal for injective Nica covariant Toeplitz representations of X which preserve the gauge coaction. Under appropriate amenability criteria, this co-universal C*-algebra coincides with the Cuntz-Nica-Pimsner algebra introduced by
DeTao Mao, Wenyuan Li
For the basic maximum likelihood estimating function of the two parameters Weibull distribution, a simple proof on its global monotonicity is given to ensure the existence and uniqueness of its solution. The boundary of the function's first-order derivative is defined based on its scale-free property. With a bounded derivative, the possible range of the
Melanie Becker, Paul Bruillard, Sean Downes
We study the linearized approximation of N=1 topologically massive supergravity around AdS3. Linearized gravitino fields are explicitly constructed. For appropriate boundary conditions, the conserved charges demonstrate chiral behavior, so that chiral gravity can be consistently extended to chiral supergravity.
Masaaki Harada, Tsuyoshi Miezaki
In this paper, we give a new upper bound on the minimum Euclidean weight of Type II $\ZZ_{2k}$-codes and the concept of extremality for the Euclidean weights when $k=3,4,5,6$. Together with the known result, we demonstrate that there is an extremal Type II $\ZZ_{2k}$-code of length $8m$ $(m \le 8)$ when $k=3,4,5,6$.
Tad Hogg, Robert A. Freitas
The power available to microscopic robots (nanorobots) that oxidize bloodstream glucose while aggregated in circumferential rings on capillary walls is evaluated with a numerical model using axial symmetry and time-averaged release of oxygen from passing red blood cells. Robots about one micron in size can produce up to several tens of picowatts, in steady-s
Jared A. Rinehimer, Gerald A. Miller
The physical nucleon is modeled as a bare nucleon surrounded by a pion cloud using a psuedoscalar pion-nucleon coupling to examine its implications for the neutron form factor, F_1, and the corresponding transverse charge density in the infinite momentum frame. Two versions, one with a tunable Pauli-Villars parameter, and one with light-front cloudy-bag pion