January 2011 arXiv papers — page 23
Showing 2,201–2,300 of 5,800 papers
J. M. Lawrence, C. H. Wang, A. D. Christianson, E. D. Bauer
In an effort to explore the differences between rare-earth-based and uranium-based heavy Fermion (HF) compounds that reflect the underlying difference between local 4$f$ moments and itinerant 5$f$ moments we analyze scaling laws that relate the low temperature neutron spectra of the primary ("Kondo-esque") spin fluctuation to the specific heat and su
Agnes Bischoff-Kim, Travis S. Metcalfe
The asteroseismic analysis of white dwarfs allows us to peer below their photospheres and determine their internal structure. At ~ 28,000 K EC20058-5234 is the hottest known pulsating helium atmosphere white dwarf. As such, it constitutes an important link in the evolution of white dwarfs down the cooling track. It is also astrophysically interesting because
Massimo Tinto
We estimate the sensitivity to nano-Hertz gravitational waves of pulsar timing experiments in which two highly-stable millisecond pulsars are tracked simultaneously with two neighboring radio telescopes that are referenced to the same time-keeping subsystem (i.e. "the clock"). By taking the difference of the two time-of-arrival residual data streams
Felix Schlenk, Pieralberto Sicbaldi
We prove the existence of a smooth family of non-compact domains $Omega_s \subset R^{n+1}$ bifurcating from the straight cylinder $B^n \times R$ for which the first eigenfunction of the Laplacian with 0 Dirichlet boundary condition also has constant Neumann data at the boundary. The domains $Omega_s$ are rotationally symmetric and periodic with respect to th
Chris J. Pickard, R. J. Needs
It is essential to know the arrangement of the atoms in a material in order to compute and understand its properties. Searching for stable structures of materials using first-principles electronic structure methods, such as density functional theory (DFT), is a rapidly growing field. Here we describe our simple, elegant and powerful approach to searching for
M. Ramzan, M. K. Khan
We study the effect of decoherence on a qubit-qutrit system under the influence of global, local and multilocal decoherence in non-inertial frames. We show that the entanglement sudden death can be avoided in non-inertial frames in the presence of amplitude damping, depolarizing and phase damping channels. However, degradation of entanglement is seen due to
Realization of an isolated Dirac node and strongly modulated Spin Texture in the topological insulator Bi2Te3
cond-mat.mes-hallSu-Yang Xu, L. A. Wray, Y. Xia, F. von Rohr
The development of spin-based applications of topological insulators requires the knowledge and understanding of spin texture configuration maps as they change via gating in the vicinity of an isolated Dirac node. An isolated (graphene-like) Dirac node, however, does not exist in Bi2Te3. While the isolation of surface states via transport channels has been p
Destruction of massive fragments in protostellar disks and crystalline silicate production
astro-ph.SREduard I. Vorobyov
We present a mechanism for the crystalline silicate production associated with the formation and subsequent destruction of massive fragments in young protostellar disks. The fragments form in the embedded phase of star formation via disk fragmentation at radial distances \ga 50-100 AU and anneal small amorphous grains in their interior when the gas temperatu
Comment on "Families of Particles with Different Masses in PT-Symmetric Quantum Field Theory" [arXiv:1002.3253]
hep-thAbouzeid. M. Shalaby
In a recent letter by Carl M. Bender and S. P. Klevansky [arXiv:1002.3253] an elementary field theory is proposed where the authors claimed that it can account for the existence of family of particles without any employment of group structures. In this work, we relied on the fact that the Dyson-Schwinger equations used by the authors stem from a variational
Nicolae Cleju, Nikolaos Thomos, Pascal Frossard
Network coding permits to deploy distributed packet delivery algorithms that locally adapt to the network availability in media streaming applications. However, it may also increase delay and computational complexity if it is not implemented efficiently. We address here the effective placement of nodes that implement randomized network coding in overlay netw
Giorgio Metafune, Chiara Spina
We prove heat kernel bounds for the operator (1 + |x|^α)Δin R^N, through Nash inequalities and weighted Hardy inequalities.
Ornella Greco
In this work, we try to draw a comparison among the three different concepts of irreducibility, given by Fletcher, Galovich, Bouvier; these three concepts are equivalent in a particular class of rings, called 'rings with only harmless zero divisors'.
Oliver Gressel, Detlef Elstner, Günther Rüdiger
The fractal shape and multi-component nature of the interstellar medium together with its vast range of dynamical scales provides one of the great challenges in theoretical and numerical astrophysics. Here we will review recent progress in the direct modelling of interstellar hydromagnetic turbulence, focusing on the role of energy injection by supernova exp
Guanghui Huang, Jianping Wan, Cheng Chen
In order to protect brokers from customer defaults in a volatile market, an active margin system is proposed for the transactions of margin lending in China. The probability of negative return under the condition that collaterals are liquidated in a falling market is used to measure the risk associated with margin loans, and a recursive algorithm is proposed
Localization of collisionally inhomogeneous condensates in a bichromatic optical lattice
cond-mat.quant-gasYongshan Cheng, S. K. Adhikari
By direct numerical simulation and variational solution of the Gross-Pitaevskii equation, we studied the stationary and dynamic characteristics of a cigar-shaped, localized, collisionally inhomogeneous Bose-Einstein condensate trapped in a one-dimensional bichromatic quasi-periodic optical-lattice potential, as used in a recent experiment on the localization
Deepak Gumber, Hemant Kalra
We study class preserving automorphisms of groups of order thirty two and prove that only two groups have non-inner class preserving automorphisms.
Study of a self-adjoint operator indicating the direction of time within standard quantum mechanics
quant-phY. Strauss, J. Silman, S. Machnes, L. P. Horwitz
In [J. Math. Phys. 51 (2010) 022104] a self-adjoint operator was introduced that has the property that it indicates the direction of time within the framework of standard quantum mechanics, in the sense that as a function of time its expectation value decreases monotonically for any initial state. In this paper we study some of this operator's properties
A. Ramos, S. Durr, Z. Fodor, C. Hoelbling
Based on a series of lattice calculations we determine the ratio FK/Fpi in QCD. With experimental data from kaon decay and nuclear double beta decay, we obtain a precise determination of |Vus|. Our simulation includes 2+1 flavours of sea quarks, with three lattice spacings, large volumes and a simulated pion mass reaching down to about 190 MeV for a full con
Pascal Auscher
We prove sharp bounds for the equivalence of norms in tent spaces with respect to changes of angles. Some applications are given.
Jean Bertoin
We consider the area $A=\int_0^{\infty}\left(\sum_{i=1}^{\infty} X_i(t)\right) \d t$ of a self-similar fragmentation process $\X=(\X(t), t\geq 0)$ with negative index. We characterize the law of $A$ by an integro-differential equation. The latter may be viewed as the infinitesimal version of a recursive distribution equation that arises naturally in this set
Existence and stability of weak solutions for a degenerate parabolic system modelling two-phase flows in porous media
math.APJoachim Escher, Philippe Laurencot, Bogdan-Vasile Matioc
We prove global existence of nonnegative weak solutions to a degenerate parabolic system which models the interaction of two thin fluid films in a porous medium. Furthermore, we show that these weak solutions converge at an exponential rate towards flat equilibria.
Contruction of holomorphic parameters invariant by change of variable in the Gauss-Manin connection of an holomorphic map to a disc
math.AGDaniel Barlet
When we consider a proper holomorphic map \ $\tilde{f}: X \to C$ \ of a complex manifold \ $X$ \ on a smooth complex curve \ $C$ \ with a critical value at a point \ $0$ \ in \ $C$, the choice of a local coordinate near this point allows to dispose of an holomorphic function \ $f$. Then we may construct, using this function, an (a,b)-modules structure on the
Yalçın Kumbasar, Ayşe Hümeyra Bilge
It is well known that a commuting family of diagonalizable linear operators on a finite dimensional vector space is simultaneously diagonalizable. In this paper, we consider a family A of anti-commuting (complex) linear operators on a finite dimensional vector space V. We prove that if the family is diagonalizable over the complex numbers, then V has an A-in
Greg N. Frederickson, Barry Wittman
A bicriteria approximation algorithm is presented for the unrooted traveling repairman problem, realizing increased profit in return for increased speedup of repairman motion. The algorithm generalizes previous results from the case in which all time windows are the same length to the case in which their lengths can range between l and 2. This analysis can e
Daniel Barlet
In this paper we introduce the word "fresco" to denote a $[λ]-$primitive monogenic geometric (a,b)-module. The study of this "basic object" (generalized Brieskorn module with one generator) which corresponds to the minimal filtered (regular) differential equation satisfied by a relative de Rham cohomology class, began in [B.09] where the firs
Band structure calculations of CuAlO2, CuGaO2, CuInO2 and CuCrO2 by screened exchange
cond-mat.str-elRoland Gillen, John Robertson
We report density functional theory (DFT) band structure calculations on the transparent conducting oxides CuAlO2, CuGaO2, CuInO2 and CuCrO2. The use of the hybrid functional sX-LDA leads to considerably improved electronic properties compared to standard local density approximation (LDA) and generalized gradient approximation (GGA) approaches. We show that
A. Englert, S. Heiligenthal, W. Kinzel, I. Kanter
Networks of nonlinear units with time-delayed couplings can synchronize to a common chaotic trajectory. Although the delay time may be very large, the units can synchronize completely without time shift. For networks of coupled Bernoulli maps, analytic results are derived for the stability of the chaotic synchronization manifold. For a single delay time, cha
Neural network interpolation of the magnetic field for the LISA Pathfinder Diagnostics Subsystem
gr-qcMarc Diaz-Aguilo, Alberto Lobo, Enrique García-Berro
LISA Pathfinder is a science and technology demonstrator of the European Space Agency within the framework of its LISA mission, which aims to be the first space-borne gravitational wave observatory. The payload of LISA Pathfinder is the so-called LISA Technology Package, which is designed to measure relative accelerations between two test masses in nominal f
Masahiro Hotta
The development of techniques for manipulation of quantum information has opened the door to a variety of protocols for accomplishing unprecedented tasks. In particular, a new protocol of quantum teleportation was proposed in 2008 to achieve effective energy transportation simply via local operations and classical communication without breaking any known phy
Greg N. Frederickson, Barry Wittman
Two multivehicle routing problems are considered in the framework that a visit to a location must take place during a specific time window in order to be counted and all time windows are the same length. In the first problem, the goal is to visit as many locations as possible using a fixed number of vehicles. In the second, the goal is to visit all locations
R. Hascoët, F. Daigne, R. Mochkovitch
The huge optical brightness of GRB 080319B (the "Naked Eye Burst) makes this event really challenging for models of the prompt GRB emission. In the framework of the internal shock model, we investigate a scenario where the dominant radiative process is synchrotron emission and the high optical flux is due to the dynamical properties of the relativistic o
M. D. Maia, A. J. S. Capistrano, J. S. Alcaniz, Edmundo M. Monte
The concept of smooth deformations of a Riemannian manifolds, recently evidenced by the solution of the Poincaré conjecture, is applied to Einstein's gravitational theory and in particular to the standard FLRW cosmology. We present a brief review of the deformation of Riemannian geometry, showing how such deformations can be derived from the Einstein-Hil
Stability of boron nitride bilayers: Ground state energies, interlayer distances, and tight-binding description
cond-mat.mes-hallR. M. Ribeiro, N. M. R. Peres
We have studied boron nitride monolayer and bilayer band structures. For bilayers, the ground state energies of the different five stackings are computed using DFT in order to determine the most stable configuration. Also, the interlayer distance for the five different types of stacking in which boron-nitride bilayers can be found is determined. Using a mini
Andrew Baxter, Brian Nakamura, Doron Zeilberger
This article, dedicated to Herbert Saul Wilf on the occaison of his forthcoming 80-th birthday, describes two complementary approaches to enumeration, the "positive" and the "negative", each with its advantages and disadvantages. Both approaches are amenable to automation, and when applied to the currently active subarea, initiated in 2003 by
Oleg D. Lavrentovich, Israel Lazo, Oleg P. Pishnyak
Electrophoresis is a motion of charged dispersed particles relative to a fluid in a uniform electric field. The effect is widely used to separate macromolecules, to assemble colloidal structures, to transport particles in nano- and micro-fluidic devices and displays. Typically, the fluid is isotropic (for example, water) and the electrophoretic velocity is l
Elon Lindenstrauss, Uri Shapira
We give new classes of examples of orbits of the diagonal group in the space of unit volume lattices in R^d for d > 2 with nice (homogeneous) orbit closures, as well as examples of orbits with explicitly computable but irregular orbit closures. We give Diophantine applications to the former, for instance we show that if x is the cubic root of 2 then for any
B. Guillot, N. Sator
The distribution, recycling and storage of carbon in the Earth are of fundamental importance to understand the global carbon cycle between the deep Earth and near surface reservoirs. Degassing of CO2 at mid-ocean ridges may give information on the source region but the very low solubility of CO2 in tholeitic basalts has for consequence that near all Mid-Ocea
IceCube Collaboration, R. Abbasi, Y. Abdou, T. Abu-Zayyad
SN 2008D, a core collapse supernova at a distance of 27 Mpc, was serendipitously discovered by the Swift satellite through an associated X-ray flash. Core collapse supernovae have been observed in association with long gamma-ray bursts and X-ray flashes and a physical connection is widely assumed. This connection could imply that some core collapse supernova
Uri Shapira
Given a continuous function from Euclidean space to the real line, we analyze (under some natural assumption on the function), the set of values it takes on translates of lattices. Our results are of the flavor: For almost any translate, the set of values is dense in the set of possible values. The results are then applied to a variety of concrete examples,
Manohar Kumar, Oren Tal, Roel H. M. Smit, Jan M. van Ruitenbeek
Pt is known to show spontaneous formation of chains of metal atoms upon breaking a metallic contact. From model calculations these have been predicted to be spin polarized, which is reasonable in view of the Stoner enhanced susceptibility of bulk Pt and the increased density of states due to the reduced dimensionality. Here, we demonstrate that shot noise re
Helmut Satz
A Short Introduction
V. Kobelev
The Article demonstrates the spontaneous symmetry breaking of isotropic homogeneous elastic medium in form of transition from Euclidean to Riemann-Cartan internal geometry of medium. The deformation of elastic medium without defects is based on Euclidean geometry in three dimensional space. The deformation of elastic medium with defects is based on Riemann-C
Effects of Explosion Asymmetry and Viewing Angle on the Type Ia Supernova Color and Luminosity Calibration
astro-ph.COK. Maeda, G. Leloudas, S. Taubenberger, M. Stritzinger
Phenomenological relations exist between the peak luminosity and other observables of type Ia supernovae (SNe~Ia), that allow one to standardize their peak luminosities. However, several issues are yet to be clarified: SNe~Ia show color variations after the standardization. Also, individual SNe~Ia can show residuals in their standardized peak absolute magnit
Jochen Heitger
I convey an idea of the significant recent progress, which opens up good perspectives for high-precision ab-initio computations in heavy flavour physics based on lattice QCD. This report focuses on the strategy and the challenges of fully non-perturbative investigations in the B-meson sector, where the b-quark is treated within an effective theory, as follow
V. Kobelev
In this article we investigate mathematically the variant of post-Newtonian mechanics using generalized fractional derivatives. The relativistic-covariant generalization of the classical equations for gravitational field is studied. The equations match to (i) the weak Newtonian limit on the moderate scales, (ii) deliver a potential higher, that Newtonian, on
Dan Hefetz, Mirjana Rakić, Miloš Stojaković
In this paper we study the (a : b) Maker-Breaker Connectivity game, played on the edge-set of the complete graph on n vertices. We determine the winner for almost all values of a and b.
Steven R. Finch
Among several things, we find the side density for random triangles circumscribing the unit circle and calculate that its median is 5.5482.... An analogous exact computation for perimeter density remains open.
Bilayer graphene with single and multiple electrostatic barriers: band structure and transmission
cond-mat.mes-hallM. Barbier, P. Vasilopoulos, F. M. Peeters, J. Milton Pereira
We evaluate the electronic transmission and conductance in bilayer graphene through a finite number of potential barriers. Further, we evaluate the dispersion relation in a bilayer graphene superlattice with a periodic potential applied to both layers. As a model we use the tight-binding Hamiltonian in the continuum approxi- mation. For zero bias the dispers
Heide Gluesing-Luerssen, Elizabeth A. Weaver
This paper focuses on dualizing tail-biting trellises, particularly KV-trellises. These trellises are based on characteristic generators, as introduced by Koetter/Vardy (2003), and may be regarded as a natural generalization of minimal conventional trellises, even though they are not necessarily minimal. Two dualization techniques will be investigated: the l
Collateral Margining in Arbitrage-Free Counterparty Valuation Adjustment including Re-Hypotecation and Netting
q-fin.RMDamiano Brigo, Agostino Capponi, Andrea Pallavicini, Vasileios Papatheodorou
This paper generalizes the framework for arbitrage-free valuation of bilateral counterparty risk to the case where collateral is included, with possible re-hypotecation. We analyze how the payout of claims is modified when collateral margining is included in agreement with current ISDA documentation. We then specialize our analysis to interest-rate swaps as
Pratika Dayal
We are in the golden age for the search for high-redshift galaxies, made possible by a combination of new instruments and innovative search techniques. One of the major aims of such searches is to constrain the epoch of reionization (EoR), which marks the second major change in the ionization state of the Universe. Understanding the EoR is difficult since wh
T. J. Hobbs, J. T. Londergan, D. P. Murdock, A. W. Thomas
We examine the possibility that one could measure partonic charge symmetry violation (CSV) by comparing neutrino or antineutrino production through charged-current reactions induced by electrons or positrons at a possible electron collider at the LHC. We calculate the magnitude of CSV that might be expected at such a facility. We show that this is likely to
F. Pinski, A. M. Stuart, F. Theil
Chemical reactions can be modelled via diffusion processes conditioned to make a transition between specified molecular configurations representing the state of the system before and after the chemical reaction. In particular the model of Brownian dynamics - gradient flow subject to additive noise - is frequently used. If the chemical reaction is specified t
Chang-Woo Lee, Mauro Paternostro, Hyunseok Jeong
We investigate the violation of Leggett's inequality for non-local realism using entangled coherent states and various types of local measurements. We prove mathematically the relation between the violation of the Clauser-Horne-Shimony-Holt form of Bell's inequality and Leggett's one when tested by the same resources. For Leggett inequalities, we
A Lower Bound for the First Passage Time Density of the Suprathreshold Ornstein-Uhlenbeck Process
math.PRPeter J. Thomas
We prove that the first passage time density $ρ(t)$ for an Ornstein-Uhlenbeck process $X(t)$ obeying $dX=-βX dt + σdW$ to reach a fixed threshold $θ$ from a suprathreshold initial condition $x_0>θ>0$ has a lower bound of the form $ρ(t)>k \exp\left[-p e^{6βt}\right]$ for positive constants $k$ and $p$ for times $t$ exceeding some positive value $u$. We obtain
T. V. Zaqarashvili, M. K. Khodachenko, H. O. Rucker
We derive the dynamics of magnetohydrodynamic waves in two-fluid partially ionized plasmas and to compare the results with those obtained under single-fluid description. Two-fluid magnetohydrodynamic equations are used, where ion-electron plasma and neutral particles are considered as separate fluids. Dispersion relations of linear magnetohydrodynamic waves
T. V. Zaqarashvili, K. Murawski, M. K. Khodachenko, D. Lee
We aim to study excitation of the observed 5-min oscillations in the solar corona by localized pulses that are launched in the photosphere. We solve the full set of nonlinear one-dimensional Euler equations numerically for the velocity pulse propagating in the solar atmosphere that is determined by the realistic temperature profile. Numerical simulations sho
R. Rossignoli, N. Canosa, J. M. Matera
We examine the entanglement of cyclic spin 1/2 chains with anisotropic XY Z Heisenberg couplings of arbitrary range at transverse factorizing magnetic fields. At these fields the system exhibits a degenerate symmetry-breaking separable ground state (GS). It is shown, however, that the side limits of the GS pairwise entanglement at these fields are actually n
T. Eronen, D. Gorelov, J. Hakala, J. C. Hardy
The Q_EC values of the superallowed beta+ emitters 10-C, 34-Ar, 38-Ca and 46-V have been measured with a Penning-trap mass spectrometer to be 3648.12(8), 6061.83(8), 6612.12(7) and 7052.44(10) keV, respectively. All four values are substantially improved in precision over previous results.
Baishun Lai
We study the following semilinear biharmonic equation $$ \left\{\begin{array}{lllllll} Δ^{2}u=\fracλ{1-u}, &\quad \mbox{in}\quad \B, u=\frac{\partial u}{\partial n}=0, &\quad \mbox{on}\quad \partial\B, \end{array} \right. %\eqno(M_λ) $$ where $\B$ is the unit ball in $\R^{n}$ and $n$ is the exterior unit normal vector. We prove the existence of $λ^{*}>0$ suc
F. J. Bertoloto, G. Botelho, V. V. Fávaro, A. M. Jatobá
In this paper we use Nachbin's holomorphy types to generalize some recent results concerning hypercyclic convolution operators on Fréchet spaces of entire functions of bounded type of infinitely many complex variables.
M. Barbier, F. M. Peeters, P. Vasilopoulos, J. Milton Pereira
We evaluate the dispersion relation for massless fermions, described by the Dirac equation, and for zero-spin bosons, described by the Klein-Gordon equation, moving in two dimensions and in the presence of a one-dimensional periodic potential. For massless fermions the dispersion relation shows a zero gap for carriers with zero momentum in the direction para
Jagjit Singh Matharu, Mohammad Sal Moslehian, Jaspal Singh Aujla
We present a weak majorization inequality and apply it to prove eigenvalue and unitarily invariant norm extensions of a version of the Bohr's inequality due to Vasić and Kečkić.
Integrated monitoring of multi-domain backbone connections -- Operational experience in the LHC optical private network
cs.NIPatricia Marcu, David Schmitz, Wolfgang Fritz, Mark Yampolskiy
Novel large scale research projects often require cooperation between various different project partners that are spread among the entire world. They do not only need huge computing resources, but also a reliable network to operate on. The Large Hadron Collider (LHC) at CERN is a representative example for such a project. Its experiments result in a vast amo
M. Erfanian Omidvar, M. S. Moslehian, A. Niknam
We present several operator and norm inequalities for Hilbert space operators. In particular, we prove that if $A_{1},A_{2},...,A_{n}\in {\mathbb B}({\mathscr H})$, then \[|||A_{1}A_{2}^{*}+A_{2}A_{3}^{*}+...+A_{n}A_{1}^{*}|||\leq|||\sum_{i=1}^{n}A_{i}A_{i}^{*}|||,\] for all unitarily invariant norms. We also show that if $A_{1},A_{2},A_{3},A_{4}$ are projec
Inter-organizational fault management: Functional and organizational core aspects of management architectures
cs.NIPatricia Marcu, Wolfgang Hommel
Outsourcing -- successful, and sometimes painful -- has become one of the hottest topics in IT service management discussions over the past decade. IT services are outsourced to external service provider in order to reduce the effort required for and overhead of delivering these services within the own organization. More recently also IT services providers t
Pavel G. Kovadlo, Olga S. Kochetkova
Meteorological data have been used to calculate refractive index fluctuations - the indicator of optical instability of the Earth's atmosphere. The calculations were made for standard pressure levels of the atmosphere in winter and summer. They are presented as distributions over the Earth's surface. The findings enabled us to determine preferred are
Wang Yao
We show that dynamic spin polarization by collective raising and lowering operators can drive a spin ensemble from arbitrary initial state to many-body singlets, the zero-collective-spin states with large scale entanglement. For an ensemble of $N$ arbitrary spins, both the variance of the collective spin and the number of unentangled spins can be reduced to
Mutation-selection dynamics and error threshold in an evolutionary model for Turing Machines
q-bio.PEFabio Musso, Giovanni Feverati
We investigate the mutation-selection dynamics for an evolutionary computation model based on Turing Machines that we introduced in a previous article. The use of Turing Machines allows for very simple mechanisms of code growth and code activation/inactivation through point mutations. To any value of the point mutation probability corresponds a maximum amoun
Edson Agustini, Sueli I. R. Costa
We introduce and discuss the concept of Gaussian probability density function (pdf) for the n-dimensional hyperbolic space which has been proposed as an environment for coding and decoding signals. An upper bound for the error probability of signal transmission associated with the hyperbolic distance is established. The pdf and the upper bound were developed
Sevag Gharibian, Julia Kempe
Approximation algorithms for classical constraint satisfaction problems are one of the main research areas in theoretical computer science. Here we define a natural approximation version of the QMA-complete local Hamiltonian problem and initiate its study. We present two main results. The first shows that a non-trivial approximation ratio can be obtained in
Habib G. Khosroshahi
We report on the Iranian National Observatory (INO) ongoing site characterization studies for INO 3.4m optical telescope under development. Iran benefits from high altitude mountains and a relatively dry climate, thus offer many suitable sites for optical observations. The site selection (2001-2007) studies resulted in two promising sites in central Iran, on
Estimation of the dome seeing from results of the optics quality tests with Shack-Hartman wavefront sensor
astro-ph.IMS. A. Potanin
The Shack-Hartman wavefront sensor designed for final acceptance of 2.5m SAI telescope allows to measure the shape of the wavefront on exit pupil of the telescope using a bright star. The reference laser source on wavelength 532 nm is used for measurements. During testing the device at different telescopes it was found out what it's probable to estimate
K. Karafasoulis, K. Zachariadou, S. Seferlis, I. Kaissas
Extensive simulations of a portable radiation detecting system have been performed in order to explore important performance parameters. The instrument consists of a stack of ten detecting layers made of pixelated Cadmium Telluride (CdTe) crystals. Its aim is to localize and identify radiation sources, by exploiting the Compton imaging technique. In this pap
F. -C. Liu, B. Parise, L. Kristensen, R. Visser
Although deuterium enrichment of water may provide an essential piece of information in the understanding of the formation of comets and protoplanetary systems, only a few studies up to now have aimed at deriving the HDO/H2O ratio in low-mass star forming regions. Previous studies of the molecular deuteration toward the solar-type class 0 protostar, IRAS 162
Christoph Walker
We give an application of the Crandall-Rabinowitz theorem on local bifurcation to a system of nonlinear parabolic equations with nonlocal reaction and cross-diffusion terms as well as nonlocal initial conditions. The system arises as steady-state equations of two interacting age-structured populations.
Flavio Romano, Francesco Sciortino
Recent experimental work on spherical colloidal particles decorated with two hydrophobic poles separated by an electrically-charged middle band (triblock Janus particles) has documented self-assembly into a Kagome two-dimensional lattice, when particles are confined by gravity at the bottom of the sample holder [Q. Chen {\em et. al.}, Nature, in press]. Here
Lusine Sargsyan, Daniel Weedman, Vianney Lebouteiller, James Houck
We present spectroscopic results for all galaxies observed with the Spitzer Infrared Spectrograph (IRS) which also have total infrared fluxes f(ir) measured with the Infrared Astronomical Satellite (IRAS), also using AKARI photometry when available. Infrared luminosities and spectral energy distributions (SEDs) from 8 um to 160 um are compared to polycyclic
Temperature independent diffuse scattering and elastic lattice deformations in relaxor PbMg1/3Nb2/3O3
cond-mat.mtrl-sciR. G. Burkovsky, S. B. Vakhrushev, K. Hirota, M. Matsuura
The results of diffuse neutron scattering experiment on PbMg1/3Nb2/3O3 single crystal above the Burns temperature are reported. It is shown that the high temperature elastic diffuse component is highly anisotropic in low-symmetry Brillouin zones and this anisotropy can be described using Huang scattering formalism assuming that the scattering originates from
Pu Zhang
The monomorphism category $\mathcal S_n(\mathcal X)$ is introduced, where $\mathcal X$ is a full subcategory of the module category $A$-mod of Artin algebra $A$. The key result is a reciprocity of the monomorphism operator $\mathcal S_n$ and the left perpendicular operator $^\perp$: for a cotilting $A$-module $T$, there is a canonical construction of a cotil
Pu Zhang
nspired by the work of J$ø$rgensen [J], we define a (upper-, lower-) symmetric recollements; and give a one-one correspondence between the equivalent classes of the upper-symmetric recollements and one of the lower-symmetric recollements, of a triangulated category. Let $\m = \left(\begin{smallmatrix} A&M 0&B \end{smallmatrix}\right)$ with bimodule $_AM_B$.
Effect of running coupling on photons from jet - plasma interaction in relativistic heavy ion collisions
hep-phLusaka Bhattacharya, Pradip Roy
We discuss the role of collisional energy loss on high $p_T$ photon data measured by PHENIX collaboration by calculating photon yield in jet-plasma interaction. The phase space distribution of the participating jet is dynamically evolved by solving Fokker-Planck equation. We treat the strong coupling constant ($α_s$) as function of momentum and temperature w
Gavin Leithall, Matthias Schmidt
We represent the free energy functional by a diagrammatic series with tensorial coefficients indexed by powers of length scale. For hard cores, we obtain Percus' exact functional in one dimension and the Kierlik-Rosinberg form of fundamental measures theory in three dimensions. In five dimensions, the functional describes bulk fluids better than Percus-Y
Luca Merlo
In view of the fact that the data on neutrino mixing are still compatible with a situation where Bimaximal mixing is valid in first approximation and it is then corrected by terms of order of the Cabibbo angle, we present examples where these properties are naturally realized. The models are supersymmetric in 4-dimensions and based on the discrete non-Abelia
R. J. van Weeren, H. J. A. Rottgering, M. Bruggen
Galaxy clusters grow by a sequence of mergers with other clusters and galaxy groups. During these mergers, shocks and/or turbulence are created within the intracluster medium (ICM). In this process, particles could be accelerated to highly relativistic energies. The synchrotron radiation from these particles is observed in the form of radio relics and halos
Gonzalo J. Olmo
We review the recent literature on modified theories of gravity in the Palatini approach. After discussing the motivations that lead to consider alternatives to Einstein's theory and to treat the metric and the connection as independent objects, we review several topics that have been recently studied within this framework. In particular, we provide an i
A. Bernal, A. Perez
We revisit the analytical properties of the static quasi-photon polarizability function for an electron gas at finite temperature, in connection with the existence of Friedel oscillations in the potential created by an impurity. In contrast with the zero temperature case, where the polarizability is an analytical function, except for the two branch cuts whic
Development of Richtmyer-Meshkov and Rayleigh-Taylor Instability in presence of magnetic field
physics.plasm-phManoranjan Khan, Labakanta Mandal, Rahul Banerjee, Sourav Roy
Fluid instabilities like Rayleigh-Taylor,Richtmyer-Meshkov and Kelvin-Helmholtz instability can occur in a wide range of physical phenomenon from astrophysical context to Inertial Confinement Fusion(ICF).Using Layzer's potential flow model, we derive the analytical expressions of growth rate of bubble and spike for ideal magnetized fluid in R-T and R-M c
Mohammed H. Sqalli, Sadiq M. Sait, Syed Asadullah
In operational networks, nodes are connected via multiple links for load sharing and redundancy. This is done to make sure that a failure of a link does not disconnect or isolate some parts of the network. However, link failures have an effect on routing, as the routers find alternate paths for the traffic originally flowing through the link which has failed
Michal Kupsa
The local return rates have been introduced by Hirata, Saussol and Vaienti \cite{HSV99} as a tool for the study of the asymptotic distribution of the return times to cylinders. We give formulas for these rates in Sturmian subshifts.
S. Sivakumar
Photon-added coherent states have been realized in optical parametric down-conversion by Zavatta {\em et al} [Science 306 (2004) 660-662]. In this report, it is established that the states generated in the process are {\em ideal} photon-added coherent states. It is shown that the scheme can generate higher order photon-added coherent states. A comparative st
Combined effect of viscosity and vorticity on single mode Rayleigh -Taylor instability bubble growth
physics.plasm-phRahul Banerjee, Labakanta Mandal, S. Roy, M. Khan
The combined effect of viscosity and vorticity on the growth rate of the bubble associated with single mode Rayleigh -Taylor instability is investigated. It is shown that the effect of viscosity on the motion of the lighter fluid associated with vorticity accumulated inside the bubble due to mass ablation may be such as to reduce the net viscous drag on the
Lung-Hui Chen
We examine an inverse backscattering property of wave motion imposed by an obstacle. We show that if the wave propagator decays super-exponentially along the back-scattered geodesics, then the involved scatterer must be trivial. In particular, if the fundamental solution decays super-exponentially some time after t=0, it vanishes for all time. We use finite
Guillaume Deltour
This thesis studies the symplectic structure of holomorphic coadjoint orbits, and their projections. A holomorphic coadjoint orbit O is an elliptic coadjoint orbit which is endowed with a natural invariant Kählerian structure. These coadjoint orbits are defined for a real semi-simple connected non-compact Lie group G with finite center, such that G/K is a He
MHD simulations reveal crucial differences between solar and very-cool star magnetic structures
astro-ph.SRBenjamin Beeck, Manfred Schüssler, Ansgar Reiners
We carried out 3D radiative magnetohydrodynamic simulations of the convective and magnetic structure in the surface layers (uppermost part of the convection zone and photosphere) of main-sequence stars of spectral types F3 to M2. The simulation results were analyzed in terms of sizes and properties of the convection cells (granules) and magnetic flux concent
Heling Yan, Zuhui Fan
We study large-scale structures from numerical simulations, paying particular attention to supercluster-like structures. A grid-density-contour based algorithm is adopted to locate connected groups. With the increase of the linking density threshold, the foam- like cosmic web is subsequently broken into individual supercluster-like groups and further halos w
Javier E. Villegas, Ivan K. Schuller
The magneto-transport of a superconducting/ferromagnetic hybrid structure consisting of a superconducting thin film in contact with an array of magnetic nanodots in the so-called "magnetic vortex-state" exhibits interesting properties. For certain magnetic states, the stray magnetic field from the vortex array is intense enough to drive the supercond
N. Matagne, Fl. Stancu
We propose a new method to study mixed symmetric multiplets of baryons in the context of the $1/N_c$ expansion approach. The simplicity of the method allows to better understand the role of various operators acting on spin and flavour degrees of freedom. The method is tested on two and three flavours. It is shown that the spin and flavour operators proportio
Baris Coskunuzer
In this paper, we show that there are non-properly embedded minimal surfaces with finite topology in a simply connected Riemannian 3-manifold with nonpositive curvature. We show this result by constructing a non-properly embedded minimal plane in hyperbolic 3-space. Hence, this gives a counterexample to Calabi-Yau conjecture for embedded minimal surfaces in
L. Lamy, P. Schippers, P. Zarka, B. Cecconi
On 17 October 2008, the Cassini spacecraft crossed the southern sources of Saturn kilometric radiation (SKR), while flying along high-latitude nightside magnetic field lines. In situ measurements allowed us to characterize for the first time the source region of an extra-terrestrial auroral radio emission. Using radio, magnetic field and particle observation