September 2009 arXiv papers — page 42
Showing 4,101–4,200 of 5,691 papers
Allan J. MacLeod
We discuss the problem of finding distinct integer sets $\{x_1,x_2,...,x_n\}$ where each sum $x_i+x_j, i \ne j$ is a square, and $n \le 7$. We confirm minimal results of Lagrange and Nicolas for $n=5$ and for the related problem with triples. We provide new solution sets for $n=6$ to add to the single known set. This provides new information for problem D15
Influence of the topology on the power flux of the Italian high-voltage electrical network
physics.soc-phV. Rosato, L. Issacharoff, G. Gianese, S. Bologna
A model of the Italian 380 kV electrical transmission network has been analyzed under the topological and the functional viewpoints. The DC power flow model used to evaluate the power flux has been solved on the basis of input conditions (injected power - extracted power, line's reactances and the maximum flux capacity of each line) taken from real data.
Giulio Ciraolo
We study the 2-D Helmholtz equation in perturbed stratified media, allowing the existence of guided waves. Our assumptions on the perturbing and source terms are not too restrictive. We prove two results. Firstly, we introduce a Sommerfeld-Rellich radiation condition and prove the uniqueness of the solution for the studied equation. Then, by careful asymptot
Mike Hapgood
Radar is a critical tool for maintaining knowledge of the many ob-jects in low Earth orbit and thus for maintaining confidence that societies around the world are secure against a variety of space-based threats. It is therefore important to raise awareness that LEO objects are embedded in the envelope of relatively dense plasma that co-rotates with the Earth
Globular clusters in modified Newtonian dynamics: velocity-dispersion profiles from self-consistent models
astro-ph.GAA. Sollima, C. Nipoti
We test the modified Newtonian dynamics (MOND) theory with the velocity-dispersion profiles of Galactic globular clusters populating the outermost region of the Milky Way halo, where the Galactic acceleration is lower than the characteristic MOND acceleration a_0. For this purpose, we constructed self-consistent, spherical models of stellar systems in MOND,
Ali Mostafazadeh
We present an evaluation of some recent attempts at understanding the role of pseudo-Hermitian and PT-symmetric Hamiltonians in modeling unitary quantum systems and elaborate on a particular physical phenomenon whose discovery originated in the study of complex scattering potentials.
Spin order and lattice frustration in optimally doped manganites. A high temperature NMR study.
cond-mat.str-elN. Panopoulos, D. Koumoulis, G. Diamantopoulos, M. Belesi
The physics underlying the complex glassy phenomena, which accompany the formation of polarons in optimally doped manganites (ODM) is a cumbersome issue with many unexplained aspects. In this article we present $^{139}$La and $^{55}$Mn NMR in the temperature range 80K - 900K of ODM La$_{0.67}$Ca$_{0.33}$MnO$_3$. We show that local lattice distortions, establ
C. J. Evans, N. Bastian, Y. Beletsky, I. Brott
The Tarantula Survey is an ambitious ESO Large Programme that has obtained multi-epoch spectroscopy of over 1,000 massive stars in the 30 Doradus region of the Large Magellanic Cloud. Here we introduce the scientific motivations of the survey and give an overview of the observational sample. Ultimately, quantitative analysis of every star, paying particular
Uncertainty Factors for Stage-Specific and Cumulative Results of Indirect Measurements
physics.data-anB. P. Datta
Evaluation of a variable Yd from certain measured variable(s) Xi(s), by making use of their system-specific-relationship (SSR), is generally referred as the indirect measurement. Naturally the SSR may stand for a simple data-translation process in a given case, but a set of equations, or even a cascade of different such processes, in some other case. Further
Louis Dupaigne, Yannick Sire
We prove a Liouville-type theorem for bounded stable solutions $v \in C^2(\R^n)$ of elliptic equations of the type (-Δ)^s v= f(v)\qquad {in $\R^n$,} where $s \in (0,1)$ {and $f$ is any nonnegative function}. The operator $(-Δ)^s$ stands for the fractional Laplacian, a pseudo-differential operator of symbol $|ξ|^{2s}$.
Yashwant Singh
We calculate the entropic part of partition function of a bubble embedded in a double stranded DNA (dsDNA) by considering the total weights of possible configurations of a system of two single stranded DNA (ssDNA) of given length which start from a point along the contour of dsDNA and reunite at a position vector {\bf r} measured from the first point and the
Hybrid-functional calculations with plane-wave basis sets: The effect of the singularity correction on total energies, energy eigenvalues, and defect energy levels
cond-mat.mtrl-sciPeter Broqvist, Audrius Alkauskas, Alfredo Pasquarello
When described through a plane-wave basis set, the inclusion of exact nonlocal exchange in hybrid functionals gives rise to a singularity, which slows down the convergence with the density of sampled $k$ points in reciprocal space. In this work, we investigate to what extent the treatment of the singularity through the use of an auxiliary function is effecti
Krishnendu Chatterjee, Laurent Doyen, Thomas A. Henzinger
Nondeterministic weighted automata are finite automata with numerical weights on transitions. They define quantitative languages L that assign to each word w a real number L(w). The value of an infinite word w is computed as the maximal value of all runs over w, and the value of a run as the maximum, limsup, liminf, limit average, or discounted sum of the tr
Jacques Blum, Cédric Boulbe, Blaise Faugeras
The problem of equilibrium of a plasma in a Tokamak is a free boundary problemdescribed by the Grad-Shafranov equation in axisymmetric configurations. The right hand side of this equation is a non linear source, which represents the toroidal component of the plasma current density. This paper deals with the real time identification of this non linear source
Xavier Xarles
We show that there exists an upper bound for the number of squares in arithmetic progression over a number field that depends only on the degree of the field. We show that this bound is 5 for quadratic fields, and also that the result generalizes to $k$-powers for $k>1$.
G. S. Asanov
We show that the metrical connection can be introduced in the two-dimensional Finsler space such that entailed parallel transports along curves joining points of the underlying manifold keep the two-vector angle as well as the length of the tangent vector, thereby realizing isometries of tangent spaces under the parallel transports. The curvature tensor is f
Magyari Attila, Genge Bela, Haller Piroska
We propose a certificate-based single sign-on mechanism in distributed systems. The proposed security protocols and authentication mechanisms are integrated in a middleware. The novelty of our middleware lies on the use of XPCOM components, this way we provide a different services that can be used on every platform where Mozilla is available. The componen ba
Genge Bela, Haller Piroska
Web services use tokens provided by the WS-Security standard to implement security protocols. We propose several extensions to the WS-Security standard, including name types, key and random number extensions. The extensions are used to implement existing protocols such as ISO9798, Kerberos or BAN-Lowe. The advantages of using these implementations rather tha
K. Prasad, B. Sundar Rajan
A single-source network is said to be \textit{memory-free} if all of the internal nodes (those except the source and the sinks) do not employ memory but merely send linear combinations of the incoming symbols (received at their incoming edges) on their outgoing edges. Memory-free networks with delay using network coding are forced to do inter-generation netw
Influence of substrate bias on the structural and dielectrical properties of magnetron-sputtered BaxSr1-xTiO3 thin films
cond-mat.mtrl-sciTommi Riekkinen, Jan Saijets, Pasi Kostamo, Timo Sajavaara
The application of a substrate bias during rf magnetron sputtering alters the crystalline structure, grain morphology, lattice strain and composition of BaxSr1-xTiO3 thin films. As a result, the dielectric properties of Pt/BaxSr1-xTiO3/Pt parallel-plate capacitors change significantly. With increasing substrate bias we observe a clear shift of the ferroelect
Sayuri L Prior, G S Da Costa, Stefan C Keller
A sample of RR Lyrae (RRL) variables from the Southern Edgeworth-Kuiper Belt Object survey in regions overlapping the expected position of debris from the interaction of the Sagittarius (Sgr) dwarf galaxy with the Milky Way (RA ~ 20 and 21.5 h; distance 16-21 kpc) has been followed up spectroscopically and photometrically. The 21 photometrically confirmed ty
Laurent Demonet
We propose a new framework for categorifying skew-symmetrizable cluster algebras. Starting from an exact stably 2-Calabi-Yau category C endowed with the action of a finite group G, we construct a G-equivariant mutation on the set of maximal rigid G-invariant objects of C. Using an appropriate cluster character, we can then attach to these data an explicit sk
Simone Daflon, Katia Cunha, Ramiro de la Reza, Jon Holtzman
Sulfur abundances are derived for a sample of ten B main-sequence star members of the Orion association. The analysis is based on LTE plane-parallel model atmospheres and non-LTE line formation theory by means of a self-consistent spectrum synthesis analysis of lines from two ionization states of sulfur, SII and SIII. The observations are high-resolution spe
V. I. Gerasimenko, V. O. Shtyk, A. G. Zagorodny
The evolution equations for the generalized microscopic phase densities are introduced. The evolution equations of average values of microscopic phase densities are derived and a solution of the initial-value problem of the obtained hydrodynamic type hierarchy is constructed.
Investigation of cluster structure of light nuclei H, He and Li isotopes, in three-body final states photodisintegration processes in the energy range 50-250 MeV using photon beams of Yerevan Synchrotron
nucl-exN. Demekhina, H. Hakobyan, A. Sirunyan, H. Vartapetian
In this work we propose to investigate the cluster structure of the excited states of nuclei produced in the photodisintegration reactions on 6 Li and 7Li targets, with three bodies (clusters and nucleons) in final state using bremsstrahlung and linear polarized beams. The analysis of the experimental data with the use of Dalitz diagrams allows to investigat
M. Ghojavand, M. A. Jafarizadeh, S. Rouhani
We investigate creation of optimal entanglement in symmetric networks. The proposed network is one in which the connections are organized by a group table in other words a group association scheme. We show that optimal entanglement can be provided over such networks by adjusting couplings and initial state. We find that the optimal initial state is a simple
Eleonora Guerrini, Emmanuela Orsini, Massimiliano Sala
The most important families of non-linear codes are systematic. A brute-force check is the only known method to compute their weight distribution and distance distribution. On the other hand, it outputs also all closest word pairs in the code. In the black-box complexity model, the check is optimal among closest-pair algorithms. In this paper we provide a Gr
Optical conductivity in cluster dynamical mean field theory: formalism and application to high temperature superconductors
cond-mat.str-elNan Lin, Emanuel Gull, A. J. Millis
The optical conductivity of the one-band Hubbard model is calculated using the 'Dynamical Cluster Approximation' implementation of dynamical mean field theory for parameters appropriate to high temperature copper-oxide superconductors. The calculation includes vertex corrections and the result demonstrates their importance. At densities of one electr
Sudarshan Shinde
In this paper a two channel paraunitary filter bank is proposed, which is based on linear canonical transform, instead of discrete Fourier transform. Input-output relation for such a filter bank are derived in terms of polyphase matrices and modulation matrices. It is shown that like conventional filter banks, the LCT based paraunitary filter banks need only
Yi-Fei Wang, Chang-De Gong
A manifestation of the many-body Aharonov-Bohm effect in the magnetic-flux-tuned Mott insulators with three-spin and four-spin ring exchanges, presents as an effective tool to manipulate the ground-state spin chirality, such as, tune the magnitude continuously, switch an abrupt jump, or even reverse its sign. Such a mechanism is demonstrated explicitly in bo
E. K. Narayanan, P. K. Ratnakumar
If $f$ is a compactly supported function on the Heisenberg group and the group Fourier transform $\hat{f}(λ)$ is a finite rank operator for all $λ$ then $f$ is the zero function.
Santanu K. Maiti
A novel feature of electron transport is explored through a thin film of varying impurity density with the distance from its surface. The film, attached to two metallic electrodes, is described by simple tight-binding model and its coupling to the electrodes is treated through Newns-Anderson chemisorption theory. Quite interestingly it is observed that, in t
Difference between thermo- and pyroelectric Co- based RE-(= Nd, Y, Gd, Ce)-oxide composites measured by high-temperature gradient
cond-mat.mtrl-sciWilfried Wunderlich, Hiroyuki Fujiwara
Seebeck-Voltage measurements of Cobalt-based oxide-composites containing rare-earth elements (RE= Nd, Y, Gd, Ce) were performed under high temperature gradients up to 700 K. Several dependences were measured, Seebeeck voltage as a function of time U_S(t)or temperature difference U_S(Delta_T), closed circuited electric current as a function of Seebeck voltage
Jeffrey Hatley
An elliptic curve E defined over \Q is an algebraic variety which forms a finitely generated abelian group, and the structure theorem then implies that E = \Z^r + \Z_{tors} for some r \geq 0; this value r is called the rank of E. It is a classical problem in the study of elliptic curves to classify curves by their rank. In this paper, the author uses the met
H. X. Yang, H. F. Tian, Y. Zhang, Y. B. Qin
The transmission electron microscopy observations of the charge ordering (CO) which governs the electronic polarization in LuFe2O4-x clearly show the presence of a remarkable phase separation at low temperatures. Two CO ground states are found to adopt the charge modulations of Q1 = (1/3, 1/3, 0) and Q2 = (1/3 + y, 1/3 + y, 3/2), respectively. Our structural
Anomalous Corrections to Hall Resistivity of Spin-Polarized Two-Dimensional Holes in a GaAs/AlGaAs Heterostructure
cond-mat.mes-hallHwayong Noh, S. Lee, S. H. Chun, H. C. Kim
Hall effect of two-dimensional holes that are spin-polarized by a strong parallel magnetic field was explored with a small tilt angle. The Hall resistivity increases nonlinearly with the magnetic field and exhibits negative corrections. The anomalous negative corrections increase with the perpendicular magnetization of the two-dimensional hole system. We att
Kinetic Monte Carlo simulation of faceted islands in heteroepitaxy using multi-state lattice model
cond-mat.mes-hallChi-Hang Lam
A solid-on-solid model is generalized to study the formation of Ge pyramid islands bounded by (105) facets on Si(100) substrates in two dimensions. Each atomic column is not only characterized by the local surface height but also by two deformation state variables dictating the local surface tilt and vertical extension. These deformations phenomenologically
C. Greub, M. Neubert, B. D. Pecjak
We study the impact of next-to-next-to-leading order (NNLO) QCD corrections on partial decay rates in B --> X_u l nu decays, at leading-order in the 1/m_b expansion for shape-function kinematics. These corrections are implemented within a modified form of the BLNP framework, which allows for arbitrary variations of the jet scale mu_i \sim 1.5 GeV. Our analys
G. Chen, G. Lerman
We apply the Spectral Curvature Clustering (SCC) algorithm to a benchmark database of 155 motion sequences, and show that it outperforms all other state-of-the-art methods. The average misclassification rate by SCC is 1.41% for sequences having two motions and 4.85% for three motions.
An Fe XXVI Absorption Line in the Persistent Spectrum of the Dipping Low Mass X-ray Binary 1A 1744-361
astro-ph.HEFotis P. Gavriil, Tod E. Strohmayer, Sudip Bhattacharyya
We report on Chandra X-ray Observatory (CXO) High-Energy Transmission Grating (HETG) spectra of the dipping Low Mass X-ray Binary (LMXB) 1A 1744-361 during its July 2008 outburst. We find that its persistent emission is well modeled by a blackbody (kT ~ 1.0 keV) plus power-law ($Γ$ ~ 1.7) with an absorption edge at 7.6 keV. In the residuals of the combined s
G. Chen, S. Atev, G. Lerman
Multi-manifold modeling is increasingly used in segmentation and data representation tasks in computer vision and related fields. While the general problem, modeling data by mixtures of manifolds, is very challenging, several approaches exist for modeling data by mixtures of affine subspaces (which is often referred to as hybrid linear modeling). We translat
Li-Chin Yeh, Yen-Chang Chang, Wen-Liang Hung, Ing-Guey Jiang
Using the period and mass data of two hundred and seventy-nine extrasolar planets, we have constructed a coupled period-mass function through the non-parametric approach. This analytic expression of the coupled period-mass function has been obtained for the first time in this field. Moreover, due to a moderate period-mass correlation, the shapes of mass/peri
Lu-Lu Li, Shan-Gui Zhou, En-Guang Zhao, Werner Scheid
Starting from the WKB approximation, a new barrier penetration formula is proposed for potential barriers containing a long-range Coulomb interaction. This formula is especially proper for the barrier penetration with penetration energy much lower than the Coulomb barrier. The penetrabilities calculated from the new formula agree well with the results from t
Huaxin Lin
Let $X$ be a compact metric space which is locally absolutely retract and let $ϕ: C(X)\to C(Y, M_n)$ be a unital homomorphism, where $Y$ is a compact metric space with ${\rm dim}Y\le 2.$ It is proved that there exists a sequence of $n$ continuous maps $\alfa_{i,m}: Y\to X$ ($i=1,2,...,n$) and a sequence of sets of mutually orthogonal rank one projections $\{
Andrew Bunker, Elizabeth Stanway, Richard Ellis, Mark Lacy
The quest to discover the most distant galaxies has developed rapidly in the last decade. We are now exploring redshifts of 6 and beyond, when the Universe was less than a billion years old, an epoch when the previously-neutral intergalactic medium was reionized. The continuing discovery of galaxies at progressively higher and higher redshifts has been drive
Matthias C Wapler
Using the AdS/CFT correspondence, we study the anisotropic charge transport properties of both supersymmetric and non-supersymmetric matter fields on (2+1)-dimensional defects coupled to a (3+1)-dimensional N=4 SYM "heat bath". We focus on the cases of a finite external background magnetic field, finite net charge density and finite mass and their co
X. Hong, K. Zou, J. Zhu
We determine the quantum scattering time tau_q in six graphene samples with mobility of 4,400 < mu < 17,000 cm^2/Vs over a wide range of carrier density (1.2 < n < 6x10^{12}/cm^2). tau_q derived from Shubnikov-de Haas oscillations ranges ~25-74 fs, corresponding to a single-particle level broadening of 4.5-13 meV. The ratio of the transport to quantum scatte
David Kubiznak
We present a brief overview of black hole spacetimes admitting Killing-Yano tensors. In vacuum these include Kerr-NUT-(A)dS metrics and certain black brane solutions. In the presence of matter fields, (conformal) Killing-Yano symmetries are known to exist for the Plebanski-Demianski solution and (trivially) for any spacetime with spherical symmetry. Special
Evolving Starburst Modeling of FIR/sub-mm/mm Line Emission. III. Application to Nearby Luminous Infrared Galaxies
astro-ph.COLihong Yao
In a previous work, we showed that the observed FIR/sub-mm/mm line spectra of a starburst galaxy (M 82) can be successfully modeled in terms of the evolutionary scheme of an ensemble of giant molecular clouds (GMCs) and shells, and such studies can usefully constrain the age(s) or star formation history of a starburst galaxy. In this paper we present a preli
On the Cauchy Problem for the Korteweg-de Vries Equation with Steplike Finite-Gap Initial Data II. Perturbations with Finite Moments
nlin.SIIryna Egorova, Gerald Teschl
We solve the Cauchy problem for the Korteweg-de Vries equation with steplike quasi-periodic, finite-gap initial conditions under the assumption that the perturbations have a given number of derivatives with finite moments.
M. Chertkov, I. Kolokolov, V. Lebedev
Two-dimensional turbulence generated in a finite box produces large-scale coherent vortices coexisting with small-scale fluctuations. We present a rigorous theory explaining the $η=1/4$ scaling in the $V\propto r^{-η}$ law of the velocity spatial profile within a vortex, where $r$ is the distance from the vortex center. This scaling, consistent with earlier
Götz S. Uhrig
It is shown that the jump in the momentum distribution of Fermi gases evolves smoothly for small and intermediate times once an interaction between the fermions is suddenly switched on. The jump does not vanish abruptly. The loci in momentum space where the jumps occur are those of the noninteracting Fermi sea. No relaxation of the Fermi surface geometry tak
H. -Y. Yang, P. M. Ricker, P. M. Sutter
Galaxy clusters are valuable cosmological probes. However, cluster mass estimates rely on observable quantities that are affected by complicated baryonic physics in the intracluster medium (ICM), including feedback from active galactic nuclei (AGN). Cosmological simulations have started to include AGN feedback using subgrid models. In order to make robust pr
B. L. Higgins, B. M. Booth, A. C. Doherty, S. D. Bartlett
We present theory and experiment for the task of discriminating two nonorthogonal states, given multiple copies. We implement several local measurement schemes, on both pure states and states mixed by depolarizing noise. We find that schemes which are optimal (or have optimal scaling) without noise perform worse with noise than simply repeating the optimal s
Antoine Chambert-Loir, Yuri Tschinkel
We establish asymptotic formulae for volumes of height balls in analytic varieties over local fields and in adelic points of algebraic varieties over number fields, relating the Mellin transforms of height functions to Igusa integrals and to global geometric invariants of the underlying variety. In the adelic setting, this involves the construction of genera
C. G. Lacey, C. M. Baugh, C. S. Frenk, A. J. Benson
We use a model for the evolution of galaxies in the far-IR based on the LambdaCDM cosmology to make detailed predictions for upcoming cosmological surveys with the Herschel Space Observatory. We use the combined GALFORM semi-analytical galaxy formation model and GRASIL spectrophotometric code to compute galaxy SEDs including the reprocessing of radiation by
Aram W. Harrow
This article will examine states that superpose different amounts of entanglement and protocols that run in superposition but generate or consume different amounts of entanglement. In both cases we find a uniquely quantum difficulty: entanglement cannot be conditionally discarded without either using communication or causing decoherence. I will first describ
M. Rabus, H. J. Deeg, R. Alonso, J. A. Belmonte
The aim of this work is a detailed analysis of transit light curves from TrES-1 and TrES-2, obtained over a period of three to four years, in order to search for variabilities in observed mid-transit times and to set limits for the presence of additional third bodies. Using the IAC 80cm telescope, we observed transits of TrES-1 and TrES-2 over several years.
Bulent Kiziltan, Stephen E. Thorsett
In the absence of constraints from the binary companion or supernova remnant, the standard method for estimating pulsar ages is to infer an age from the rate of spin-down. While the generic spin-down age may give realistic estimates for normal pulsars, it can fail for pulsars with very short periods. Details of the spin-up process during the low mass X-ray b
Michael McDonald, Sylvain Veilleux
We have obtained deep, high spatial resolution images of the central region of Abell 1795 at Halpha and [NII] (6583A) with the Maryland Magellan Tunable Filter (MMTF), and in the far-ultraviolet (FUV) with the Advanced Camera for Surveys Solar Blind Channel on the Hubble Space Telescope (HST). The superb image quality of the MMTF data has made it possible to
G. Passante, O. Moussa, C. A. Ryan, R. Laflamme
We present experimental results approximating the Jones polynomial using 4 qubits in a liquid state nuclear magnetic resonance quantum information processor. This is the first experimental implementation of a complete problem for the deterministic quantum computation with one quantum bit model of quantum computation, which uses a single qubit accompanied by
The Adventures of the Rocketeer: Accelerated Motion Under the Influence of Expanding Space
astro-ph.COJuliana Kwan, Geraint F. Lewis, J. Berian James
It is well known that interstellar travel is bounded by the finite speed of light, but on very large scales any rocketeer would also need to consider the influence of cosmological expansion on their journey. This paper examines accelerated journeys within the framework of Friedmann- Lemaitre-Robertson-Walker universes, illustrating how the duration of a fixe
D. E. Chang, C. A. Regal, S. B. Papp, D. J. Wilson
Recently, remarkable advances have been made in coupling a number of high-Q modes of nano-mechanical systems to high-finesse optical cavities, with the goal of reaching regimes where quantum behavior can be observed and leveraged toward new applications. To reach this regime, the coupling between these systems and their thermal environments must be minimized
Tasho Kaletha
We prove the conjectural endoscopic transfer of L-packets for the local Langlands correspondence for pure inner forms of unramified p-adic groups and depth-zero parameters established by DeBacker and Reeder. More precisely, we show that under mild conditions on the residual characteristic, endoscopic induction identifies an unstable character of such an L-pa
M. Stobińska, P. Horodecki, A. Buraczewski, R. W. Chhajlany
The question whether Quantum Mechanics describes all aspects of both the micro-world of elementary particles and living organisms adequately is still open. A Bell inequality test without locality and detection loopholes will deliver the answer when applied to macroscopic systems. Here we show that an experimentally feasible loophole-free Bell test is possibl
P. J. Käpylä, M. J. Korpi, A. Brandenburg, D. Mitra
Self-consistent convective dynamo simulations in wedge-shaped spherical shells are presented. Differential rotation is generated by the interaction of convection with rotation. Equatorward acceleration and dynamo action are obtained only for sufficiently rapid rotation. The angular velocity tends to be constant along cylinders. Oscillatory large-scale fields
Does Galactic Magnetic Field Disturb the Correlation of the Highest Energy Cosmic Rays with their Sources?
astro-ph.HEHajime Takami, Katsuhiko Sato
The propagation trajectories of the highest energy cosmic rays (HECRs) are deflected by not only intergalactic magnetic field but also Galactic magnetic field (GMF). These magnetic fields can weaken the positive correlation between the arrival directions of HECRs and the positions of their sources. In order to explore the effect of GMF on the expected correl
Wan Keng Cheong, Amin Gholampour
We explore the theory of connected Gromov-Witten invariants of the symmetric product stack [Sym^n(A_r)]. We derive closed-form expressions for all equivariant invariants with two insertions and reveal a natural correspondence between the theory and the relative Gromov-Witten theory of the threefold A_r x P^1. When n is less than or equal to 3, we determine 3
Dust driven mass loss from carbon stars as a function of stellar parameters - I. A grid of Solar-metallicity wind models
astro-ph.SRLars Mattsson, Rurik Wahlin, Susanne Hoefner
[Abridged] We have computed a grid of 900 numeric dynamic model atmospheres (DMAs) using a well-tested computer code. This grid of models covers most of the expected combinations of stellar parameters, which are made up of the stellar temperature, the stellar luminosity, the stellar mass, the abundance of condensible carbon, and the velocity amplitude of the
Alex E. Bernardini, O. Bertolami
The theoretical description of compact structures that share some key features with mass varying particles allows for a simple analysis of equilibrium and stability for massive stellar bodies. We investigate static, spherically symmetric solutions of Einstein equations for a system composed by nonbaryonic matter (neutrinos or dark matter) which forms stable
Funding for Adaptive Optics in the United States by the National Science Foundation 2006-2009: An Update
astro-ph.IMJay A. Frogel
In 2006 I published an article in GeminiFocus that examined funding for astronomical adaptive optics related technology and instrumentation in the United States from 1995 through mid-2006. That article concluded that based on projections then current, AO implementation on public and private telescopes in the U.S. will soon seriously lag that on the ESO VLT a
Relationship Between the Azimuthal Dependencies of Nuclear Modification Factor and Ridge Yield
nucl-thRudolph C. Hwa, Lilin Zhu
The azimuthal angular dependence of the nuclear modification factor R_{AA}(p_T, phi,N_{part}) recently obtained by PHENIX is related at low p_T to the trigger phi dependence of the ridge yield as measured by STAR in a framework in which the azimuthal anisotropy is driven by semihard scattering near the surface. Careful consideration of the initial geometry l
N. Achilleos, P. Guio, C. S. Arridge
We present calculations of magnetic potential associated with the perturbation of Saturn's magnetic field by a rotating, equatorially-situated disc of plasma. Such structures are central to the dynamics of the rapidly rotating magnetospheres of Saturn and Jupiter. They are `fed' internally by sources of plasma from moons such as Enceladus (Saturn) an
A. Palazzo, J. W. F. Valle
Solar and KamLAND data are in slight tension when interpreted in the standard two-flavor oscillations framework and this may be alleviated allowing for a non-zero value of the mixing angle theta_13. Here we show that, likewise, non-standard flavor-changing interactions (FCI), possibly intervening in the propagation of solar neutrinos, are equally able to all
Holographic Approach to Finite Temperature QCD: The Case of Scalar Glueballs and Scalar Mesons
hep-phP. Colangelo, F. Giannuzzi, S. Nicotri
We study scalar glueballs and scalar mesons at $T \neq 0$ in the soft wall holographic QCD model. We find that, using the Anti-de Sitter-Black Hole metric for all values of the temperature, the masses of the hadronic states decrease and the widths become broader when T increases, and there are temperatures for which the states disappear from the scalar glueb
H. -C. Wu, T. Tajima, D. Habs, A. W. Chao
With the increasing development of laser accelerators, the electron energy is already beyond GeV and even higher in near future. Conventional beam dump based on ionization or radiation loss mechanism is cumbersome and costly, also has radiological hazards. We revisit the stopping power of high-energy charged particles in matter and discuss the associated pro
J. Harshan, B. Sundar Rajan, Are Hjørungnes
Recently, a special class of complex designs called Training-Embedded Complex Orthogonal Designs (TE-CODs) has been introduced to construct single-symbol Maximum Likelihood (ML) decodable (SSD) distributed space-time block codes (DSTBCs) for two-hop wireless relay networks using the amplify and forward protocol. However, to implement DSTBCs from square TE-CO
Francesco Benini, Yuji Tachikawa, Brian Wecht
In theories without known Lagrangian descriptions, knowledge of the global symmetries is often one of the few pieces of information we have at our disposal. Gauging (part of) such global symmetries can then lead to interesting new theories, which are usually still quite mysterious. In this work, we describe a set of tools that can be used to explore the supe
S. R. Power, V. M. de Menezes, S. B. Fagan, M. S. Ferreira
The electronic properties of low-dimensional materials can be engineered by doping, but in the case of graphene nanoribbons (GNR) the proximity of two symmetry-breaking edges introduces an additional dependence on the location of an impurity across the width of the ribbon. This introduces energetically favorable locations for impurities, leading to a degree
Chris Ford
The possibility that QED and recently developed non-Hermitian, or magnetic, versions of QED are equivalent is considered. Under this duality the Hamiltonians and anomalous axial currents of the two theories are identified. A consequence of such a duality is that particles described by QED carry magnetic as well as electric charges. The proposal requires a va
S. Belliard, N. Crampe, E. Ragoucy
We study the general L_0-regular gl(2) spin chain, i.e. a chain where the sites {i,i+L_0,i+2L_0,...} carry the same arbitrary representation (spin) of gl(2). The basic example of such chain is obtained for L_0=2, where we recover the alternating spin chain. Firstly, we review different known results about their integrability and their spectrum. Secondly, we
Palle E. T. Jorgensen, Erin P. J. Pearse
A resistance network is a connected graph $(G,c)$. The conductance function $c_{xy}$ weights the edges, which are then interpreted as conductors of possibly varying strengths. The Dirichlet energy form $\mathcal E$ produces a Hilbert space structure ${\mathcal H}_{\mathcal E}$ on the space of functions of finite energy. The relationship between the natural D
Pedro D. Alvarez
In this thesis some systems with exotic symmetries, which are a peculiarity in 2+1 space-time dimensions, are studied. Coded in the exotic structure, there appear noncommutative coordinates and a phases structure. This kind of systems has attracted attention from different areas of physics independently. Among them, we can mention: theory of ray representati
B. A. Kniehl, A. V. Kotikov, O. L. Veretin
Recently, the O(alpha) and O(alpha^3 ln(alpha)) radiative corrections to the orthopositronium lifetime have been presented in closed analytical form, in terms of basic irrational numbers that can be evaluated numerically to arbitrary precision [Phys. Rev. Lett. 101, 193401 (2008)]. Here, we present the details of this calculation and reveal the nature of the
Yang Bai, Marcela Carena, Joseph Lykken
A dilaton could be the dominant messenger between Standard Model fields and dark matter. The measured dark matter relic abundance relates the dark matter mass and spin to the conformal breaking scale. The dark matter-nucleon spin-independent cross section is predicted in terms of the dilaton mass. We compute the current constraints on the dilaton from LEP an
Keisuke Hatada, Kuniko Hayakawa, Fabrizio Palumbo
We recently suggested that the Scissors Mode (a collective excitation in which one system rotates with respect another one conserving its shape) can occur in crystals with axially symmetric atoms as a precession of these atoms around the anisotropy axis of their cells, giving rise to a form of dichroism. In the present paper we investigate how the Scissors M
Xabier Domínguez Vaja Tarieladze
In a recent paper by D. Shakhmatov and J. Spěvák [Group-valued continuous functions with the topology of pointwise convergence, Topology and its Applications (2009), doi:10.1016/j.topol.2009.06.022] the concept of a ${\rm TAP}$ group is introduced and it is shown in particular that ${\rm NSS}$ groups are ${\rm TAP}$. We prove that conversely, Weil complete m
First Measurement of the b-jet Cross Section in Events with a W Boson in p-pbar Collisions at sqrt{s} = 1.96 TeV
hep-exThe CDF Collaboration, T. Aaltonen
The cross section for jets from b quarks produced with a W boson has been measured in ppbar collision data from 1.9/fb of integrated luminosity recorded by the CDF II detector at the Tevatron. The W+b-jets process poses a significant background in measurements of top quark production and prominent searches for the Higgs boson. We measure a b-jet cross sectio
Marc Barthelemy, Jean-Pierre Nadal, Henri Berestycki
A single social phenomenon (such as crime, unemployment or birth rate) can be observed through temporal series corresponding to units at different levels (cities, regions, countries...). Units at a given local level may follow a collective trend imposed by external conditions, but also may display fluctuations of purely local origin. The local behavior is us
Ivailo I. Dimov, Petter N. Kolm, Lee Maclin, Dan Y. C. Shiber
We find a novel correlation structure in the residual noise of stock market returns that is remarkably linked to the composition and stability of the top few significant factors driving the returns, and moreover indicates that the noise band is composed of multiple subbands that do not fully mix. Our findings allow us to construct effective generalized rando
Ragab M. Gad
In this paper, we obtained a new class of axially symmetric cosmological mesonic stiff fluid models in the context of Lyra's geometry. Expressions for the energy, pressure and the massless scalar field are derived by considering the time dependent displacement field. We found that the mesonic scalar field depends on only $t$ coordinate. Some physical pro
Tao Hong, A. Zheludev, H. Manaka, L. -P. Regnault
We report the single crystal study of the bulk magnetization and neutron scattering measurements on a quantum S=1/2 spin ladders system IPA-Cu(Cl0.95Br0.05)3with quenched disorder. In zero field, the disordered spin liquid phase is preserved as in pure IPA-CuCl3. Due to the bond randomness, a different Bose glass phase was directly observed in Hc<H<H', which
Tim Gershon, Mike Williams
The potential for a precise measurement of the Unitarity Triangle angle $γ$ in future experiments from the decay $B^0 \to DK^{*0}$ is well-known. It has recently been suggested that the sensitivity can be significantly enhanced by analysing the $B^0 \to DK^+π^-$ Dalitz plot to extract amplitudes relative to those of the flavour-specific decay $B^0 \to D_2^{*
David Merritt
Motivated by recent observations that suggest a low density of old stars around the Milky Way supermassive black hole, models for the nuclear star cluster are considered that have not yet reached a steady state under the influence of gravitational encounters. A core of initial radius 1-1.5 pc evolves to a size of approximately 0.5 pc after 10 Gyr, roughly th
M. E. Povarnitsyn, T. E. Itina, K. V. Khishchenko, P. R. Levashov
We report the physical reasons of a curious decrease in the crater depth observed for long delays in experiments with femtosecond double pulses. Detailed hydrodynamic modeling demonstrates that the ablation mechanism is dumped when the delay between the pulses exceeds the electron-ion relaxation time. In this case, the interaction of the second laser pulse w
Christoph Lehner, Tilo Wettig
We calculate the partition function of partially quenched chiral perturbation theory in the epsilon regime at next-to-leading order using the supersymmetry method in the formulation without a singlet particle. We include a nonzero imaginary chemical potential and show that the finite-volume corrections to the low-energy constants $\Sigma$ and $F$ for the par
K. Belkacem, S. Mathis, M. J. Goupil, R. Samadi
We focus on the influence of the Coriolis acceleration on the stochastic excitation of oscillation modes in convective regions of rotating stars. Our aim is to estimate the asymmetry between excitation rates of prograde and retrograde modes. We extend the formalism derived for obtaining stellar $p$- and $g$-mode amplitudes (Samadi & Goupil 2001, Belkacem et
Sean February, Julien Larena, Mathew Smith, Chris Clarkson
Dark energy observations may be explained within general relativity using an inhomogeneous Hubble-scale depression in the matter density and accompanying curvature, which evolves naturally out of an Einstein-de Sitter (EdS) model. We present a simple parameterization of a void which can reproduce concordance model distances to arbitrary accuracy, but can par
U. Kiziloglu, S. Ozbilgen, N. Kiziloglu, A. Baykal
We present the relations between Halpha equivalent width, optical brightness and X-ray flux of Be/X-ray binary system SAX J2103.5+4545, by analyzing the optical photometric and spectroscopic observations together with the X-ray observations. In the photometric observations PSF photometry were applied using MIDAS and its DAOPHOT package. The reduction and ana
Monte Carlo simulation of charge transport in disordered organic systems using buffer lattice at boundary
cond-mat.dis-nnS. Raj Mohan, Manoranjan P. Singh, M. P. Joshi
In this article, we present an alternative method for simulating charge transport in disordered organic materials by using a buffer lattice at the boundary. This method does not require careful tracking of carrier's hopping pattern across boundaries. Suitability of this method is established by reproducing the field dependence of mobility, carrier relaxa