February 2009 arXiv papers — page 10
Showing 901–1,000 of 4,929 papers
R. Oliver
Quiescent prominences are thin slabs of cold, dense plasma embedded in the much hotter and rarer solar corona. Although their global shape is rather irregular, they are often characterised by an internal structure consisting of a large number of thin, parallel threads piled together. Prominences often display periodic disturbances mostly observed in the Dopp
Lower Higgs boson mass bounds from a chirally invariant lattice Higgs-Yukawa model with overlap fermions
hep-latP. Gerhold, K. Jansen
We study the coupling parameter dependence of the Higgs boson mass in a chirally invariant lattice Higgs-Yukawa model emulating the same Yukawa coupling structure as in the Higgs-fermion sector of the Standard Model. Eventually, the aim is to establish non-perturbative upper and lower Higgs boson mass bounds derived from first principles, in particular not r
V. A. Golovko
This paper represents the full version of a paper published earlier in Physica A [246 (1997), 275]. The present paper includes argumentation, proofs and details omitted in the shortened version. The papers are a further development of the approach in quantum statistical mechanics proposed by the author. The hierarchy of equations for reduced density matrices
Stanislav Babak, Jonathan R. Gair, Edward K. Porter
The gravitational wave signal from a compact object spiralling toward a massive black hole (MBH) is thought to be one of the most difficult sources to detect in the LISA data stream. Due to the large parameter space of possible signals and many orbital cycles spent in the sensitivity band of LISA, it has been estimated previously that of the order of 10^{35}
V. S. Kulikov, Vik. S. Kulikov
We investigate the problem of existence of degenerations of surfaces in $\mathbb P^3$ with ordinary singularities into plane arrangements in general position.
Mehmet Tekkoyun, Erdal Ozusaglam, Ali Gorgulu
In this paper, Lagrangian formalisms of Classical Mechanics was deduced on Kaehlerian manifold being geometric model of a generalized Lagrange space.Then, it was given two applications of complex Euler-Lagrange equations on mechanics system.
Mehmet Tekkoyun, Ali Gorgulu
The goal of this paper is to introduce the lifting theory that has an important role in geometry. Therefore, using the lifts of differential geometric structures we show that tangent bundle TM of paracomplex manifold M admits para-complex torsion-free affine connection.
Michal Godlinski, Pawel Nurowski
We address the problem of local geometry of third order ODEs modulo contact, point and fibre-preserving transformations of variables. Several new and already known geometries are described in a uniform manner by the Cartan method of equivalence. This includes conformal, Weyl and metric geometries in three and six dimensions and contact projective geometry in
Mehmet Tekkoyun, Ali Gorgulu
In this study, it is generalized the concept of Lagrangian mechanics with constraints to complex case. To be beginning, it is considered a Kaehlerian manifold as a velocity-phase space. Then a non-holonomic constraint is given by 1-form on it. If the form is closed, it is found that the constraint is (locally) holonomic. In the result, complex analogous of s
On a triangulated category which behaves like a cluster category of infinite Dynkin type, and the relation to triangulations of the infinity-gon
math.RTThorsten Holm, Peter Jorgensen
This paper investigates a certain 2-Calabi-Yau triangulated category D whose Auslander-Reiten quiver is ZA_{\infty}. We show that the cluster tilting subcategories of D form a so-called cluster structure, and we classify these subcategories in terms of what one may call `triangulations of the infinity-gon'. This is reminiscent of the cluster category C o
Mehmet Tekkoyun
In this study, taking into considering lifting theory, we shall obtain both almost complex and paracomplex structures on the tangent bun- dle, based on almost Lorentzian r-contact and r-paracontact manifold.
Piotr Bozek, Iwona Wyskiel
Hydrodynamic expansion of the hot fireball created in relativistic Au-Au collisions at 200GeV in 3+1-dimensions is studied. We obtain a simultaneous, satisfactory description of the transverse momentum spectra, elliptic flow and pion correlation radii for different collision centralities and different rapidities. Early initial time of the evolution is requir
Mehmet Tekkoyun, Murat Sari
In this study, it is introduced paracomplex analogue of Lagrangians and Hamiltonians with constraints in the framework of para-Kaehlerian manifolds. The geometrical and mechanical results on the constrained mechanical system have also been discussed.
Alessandro Patruno, Rudy Wijnands, Michiel van der Klis
The measurement of the spin frequency in accreting millisecond X-ray pulsars (AMXPs) is strongly affected by the presence of an unmodeled component in the pulse arrival times called 'timing noise'. We show that it is possible to attribute much of this timing noise to a pulse phase offset that varies in correlation with X-ray flux, such that noise in
Stephen G. Walker
This note presents a simple and elegant sampler which could be used as an alternative to the reversible jump MCMC methodology.
Khalid Kamhawi, Lennon Ó Náraigh
We study the dynamics of simple reactions where the chemical species are confined on a general, time-modulated surface, and subjected to externally-imposed stirring. The study of these inhomogeneous effects requires a model based on a reaction-advection-diffusion equation, which we derive. We use homogenization methods to show that up to second order in a sm
Frontiers of the physics of dense plasmas and planetary interiors: experiments, theory, applications
astro-ph.EPJ. J. Fortney, S. H. Glenzer, M. Koenig, B. Militzer
Recent developments of dynamic x-ray characterization experiments of dense matter are reviewed, with particular emphasis on conditions relevant to interiors of terrestrial and gas giant planets. These studies include characterization of compressed states of matter in light elements by x-ray scattering and imaging of shocked iron by radiography. Several appli
Volodymyr P. Kravchuk, Yuri Gaididei, Denis D. Sheka
It is shown that under the action of rotating magnetic field an immobile vortex, contrary to a general belief, can nucleate a vortex-antivortex pair and switch its polarity. Two different kinds of OOMMF micromagnetic modeling are used: (i) the original vortex is pinned by the highly--anisotropic easy-axes impurity at the disk center, (ii) the vortex is pinne
J. T. Padding
An efficient simulation method is presented for Brownian fiber suspensions, which includes both uncrossability of the fibers and hydrodynamic interactions between the fibers mediated by a mesoscopic solvent. To conserve hydrodynamics, collisions between the fibers are treated such that momentum and energy are conserved locally. The choice of simulation param
Alexander Bihlo
Selected applications of symmetry methods in the atmospheric sciences are reviewed briefly. In particular, focus is put on the utilisation of the classical Lie symmetry approach to derive classes of exact solutions from atmospheric models. This is illustrated with the barotropic vorticity equation. Moreover, the possibility for construction of partially-inva
The isolated neutron star RBS1774 revisited. Revised XMM-Newton X-ray parameters and an optical counterpart from deep LBT-observations
astro-ph.GAA. Schwope, T. Erben, J. Kohnert, G. Lamer
We report optical B-band observations with the Large Binocular Telescope LBT of the isolated neutron star RBS1774. The stacked image with total exposure 2.5h reveals a candidate optical counterpart at mB = 26.96 +- 0.20 at position RA(2000) = 21:43:03.4, DEC(2000)} = +06:54:17:5, within the joint Chandra and XMM-Newton error circles. We analyse archival XMM-
Shih-Chun Lin, Pin-Hsun Lin, Chung-Pi Lee, Hsuan-Jung Su
Linear-assignment Gel'fand-Pinsker coding (LA-GPC) is a coding technique for channels with interference known only at the transmitter, where the known interference is treated as side-information (SI). As a special case of LA-GPC, dirty paper coding has been shown to be able to achieve the optimal interference-free rate for interference channels with perf
P. M. Williams, G. Rauw, K. A. van der Hucht
We present infrared photometry of the episodic dust-making Wolf-Rayet system WR19 (LS3), tracking its fading from a third observed dust-formation episode in 2007 and strengthening the view that these episodes are periodic (P = 10.1+/-0.1 y). Radial velocities of the O9 component observed between 2001 and 2008 show RV variations consistent with WC19 being a s
Sol-gel obtained YSZ nanocrystals on a substrate: a Monte Carlo approach of the crystallographic orientation
cond-mat.mtrl-sciF. Lallet, N. Olivi-Tran
Sol gel obtained YZS (Yttria Stabilized Zirconia) nanocrystals have different morphologies when they grow on an $α$-alumina substrate after thermal treatment. When the substrate has planar defects, the nanocrystals grow in height and are narrow with a crystallographic orientation [111] in the vertical direction, while when the substrate is a perfect plane at
Anne Bauer, Charles Baltay, Paolo Coppi, Nancy Ellman
The ensemble variability properties of nearly 23,000 quasars are studied using the Palomar-QUEST Survey. The survey has covered 15,000 square degrees multiple times over 3.5 years using 7 optical filters, and has been calibrated specifically for variability work. Palomar-QUEST allows for the study of rare objects using multiple epochs of consistently calibra
Pavel Chebotarev, Rafig Agaev
Constructing and studying distributed control systems requires the analysis of the Laplacian spectra and the forest structure of directed graphs. In this paper, we present some basic results of this analysis partially obtained by the present authors. We also discuss the application of these results to decentralized control and touch upon some problems of spe
The asymptotic behaviour in Schwarzschild time of Vlasov matter in spherically symmetric gravitational collapse
gr-qcHakan Andreasson, Gerhard Rein
Given a static Schwarzschild spacetime of ADM mass M, it is well-known that no ingoing causal geodesic starting in the outer domain r>2M will cross the event horizon r=2M in finite Schwarzschild time. In the present paper we show that in gravitational collapse of Vlasov matter this behaviour can be very different. We construct initial data for which a black
T. Lebzelter, M. Obbrugger
We investigate the question whether there is a real difference in the light change between stars classified as semiregular (SRV) or irregular (Lb) variables by analysing photometric light curves of 12 representatives of each class. Using Fourier analysis we try to find a periodic signal in each light curve and determine the S/N of this signal. For all stars,
J. Blümlein, M. Kauers, S. Klein, C. Schneider
Single-scale quantities, like the QCD anomalous dimensions and Wilson coefficients, obey difference equations. Therefore their analytic form can be determined from a finite number of moments. We demonstrate this in an explicit calculation by establishing and solving large scale recursions by means of computer algebra for the anomalous dimensions and Wilson c
Paramita Barai, Ipsita Chakraborty, Tapas K Das, Paul J Wiita
This work introduces a novel formalism to investigate the role of the spin of astrophysical black holes in determining the behaviour of matter falling onto such accretors. Equations describing the general relativistic hydrodynamic accretion flow in the Kerr metric are formulated, and stationary solutions for such flow equations are provided. The accreting ma
Determining the closed forms of the $O(a_s^3)$ anomalous dimensions and Wilson coefficients from Mellin moments by means of computer algebra
hep-phJ. Blümlein, M. Kauers, S. Klein, C. Schneider
Single scale quantities, as anomalous dimensions and hard scattering cross sections, in renormalizable Quantum Field Theories are found to obey difference equations of finite order in Mellin space. It is often easier to calculate fixed moments for these quantities compared to a direct attempt to derive them in terms of harmonic sums and their generalizations
Superconducting density of states at the border of an amorphous thin film grown by focused-ion-beam
cond-mat.supr-conI. Guillamon, H. Suderow, S. Vieira, A. Fernandez-Pacheco
We present very low temperature Scanning Tunneling Microscopy and Spectroscopy (STM/S) measurements of a W based amorphous thin film grown with focused-ion-beam. In particular, we address the superconducting properties close to the border, where the thickness of the superconducting film decreases, and the Au substrate emerges. When approaching the Au substra
Zoran Sunic
Baer characterized capable finite abelian groups (a group is capable if it is isomorphic to the quotient of some group by its center) by a condition on the size of the factors in the invariant factor decomposition (the group must be noncyclic and the top two invariant factors must be equal). We provide a different characterization, given in terms of a condit
M R Setare
In the present paper, we provide a thermodynamical interpretation for the holographic dark energy model in a non-flat universe. For this case, the characteristic length is no more the radius of the event horizon ($R_E$) but the event horizon radius as measured from the sphere of the horizon ($L$). Furthermore, when interaction between the dark components of
Effect of Ka-band Microwave on the spin dynamics of electrons in a GaAs/Al0.35Ga0.65As heterostructure
cond-mat.mtrl-sciHaihui Luo, Xuan Qian, Xiaofang Gu, Yang Ji
We report experimental results of the effect of Ka-band microwave on the spin dynamics of electrons in a 2D electron system in a GaAs/Al0.35Ga0.65As heterostructure, via time-resolved Kerr rotation measurements. While the microwave reduces the transverse spin lifetime of the bulk GaAs when its frequency is close to the Zeeman splitting of the electrons in th
Ji-Lin Zhou
Hot super-Earths are exoplanets with masses < 10 Earth masses and orbital periods < 20 days. Around 8 hot super-Earths have been discovered in the neighborhood of solar system. In this lecture, we review the mechanisms for the formation of hot super-Earths, dynamical effects that play important roles in sculpting the architecture of the multiple planetary sy
Rafael López
In the half-space model of hyperbolic space, that is, $\r^3_{+}=\{(x,y,z)\in\r^3;z>0\}$ with the hyperbolic metric, a translation surface is a surface that writes as $z=f(x)+g(y)$ or $y=f(x)+g(z)$, where $f$ and $g$ are smooth functions. We prove that the only minimal translation surfaces (zero mean curvature in all points) are totally geodesic planes.
Antonio M. Oller-Marcen
In this paper we present a way to count the number of trains that we can construct with a given set of domino pieces. As an application we obtain a new method to compute the total number of eulerian paths in an undirected graph as well as their starting and ending vertices.
Thermal instability in X-ray photoionized media in Active Galactic Nuclei: II. Role of the thermal conduction in warm absorber
astro-ph.IMB. Czerny, L. Chevallier, A. C. Goncalves, A. Rozanska
A photoionized gas under constant pressure can display a thermal instability, with three or more solutions for possible thermal equilibrium. A unique solution of the structure of the irradiated medium is obtained only if electron conduction is considered. The subject of our study is to estimate how the effect of thermal conduction affects the structure and t
Sachie Shiomi
Superconducting gravimeters are the most sensitive instruments to measure surface gravity changes at low frequencies. Currently, about twenty five superconducting gravimeters are operating in the world and their global network has been developed. We investigate possible applications of the superconducting gravimeters to tests of gravitational physics. Previo
Fabio D. Barazza, Pascale Jablonka, Vandana Desai, Shardha Jogee
We present a study of large-scale bars in field and cluster environments out to redshifts of ~0.8 using a final sample of 945 moderately inclined disk galaxies drawn from the EDisCS project. We characterize bars and their host galaxies and look for relations between the presence of a bar and the properties of the underlying disk. We investigate whether the f
Mehmet Tekkoyun
The aim of this study is to introduce quaterinon Kaehler analogue of Lagrangian mechanics. Finally, the geometric and physical results related to quaternion Kaehler dynamical systems are also presented.
Momentum Flow in Black Hole Binaries: I. Post-Newtonian Analysis of the Inspiral and Spin-Induced Bobbing
gr-qcDrew Keppel, David A. Nichols, Yanbei Chen, Kip S. Thorne
A brief overview is presented of a new Caltech/Cornell research program that is exploring the nonlinear dynamics of curved spacetime in binary black hole collisions and mergers, and of an initial project in this program aimed at elucidating the flow of linear momentum in black-hole binaries (BBHs). The "gauge-dependence" (arbitrariness) in the localization o
Mehmet Tekkoyun
This paper presents Hamilton dynamics on Clifford Kaeler manifolds. In the end, the some results related to Clifford Kaehler dynamical systems are also discussed.
Mehmet Tekkoyun
In this study, Clifford Kaehler analogue of Lagrangian dynamics is introduced. Also,the some geometrical and physical results over the obtained Clifford Kaehler dynamical systems are discussed.
Dong Liu, Yuzhu Wu, Linsheng Zhu
We define Whittaker modules for the twisted Heisenberg-Virasoro algebra and obtain analogues to several results from the classical setting, including a classification of simple Whittaker modules by central characters.
Amelia Sparavigna
This paper proposes an algorithm for image processing, obtained by adapting to image maps the definitions of two well-known physical quantities. These quantities are the dipole and quadrupole moments of a charge distribution. We will see how it is possible to define dipole and quadrupole moments for the gray-tone maps and apply them in the development of alg
Black Holes in the Dilatonic Einstein-Gauss-Bonnet Theory in Various Dimensions III -- Asymptotically AdS Black Holes with $k=\pm 1$ --
hep-thNobuyoshi Ohta, Takashi Torii
We study black hole solutions in the Einstein-Gauss-Bonnet gravity with the dilaton and a negative ``cosmological constant''. We derive the field equations for the static spherically symmetric ($k=1$) and hyperbolically symmetric ($k=-1$) spacetime in general $D$ dimensions. The system has some scaling symmetries which are used in our analysis of the
Xavier Roulleau
We study surfaces of general type $S$ whose cotangent sheaf is generated by its global sections. We define a map called the cotangent map of $S$ that enables us to understand the obstructions to the ampleness of the cotangent sheaf of $S$. These obstructions are curves on $S$ that we call "non-ample". We classify surfaces with an infinite number of non-ample
S. Sawada-Satoh, S. Kameno, K. Nakamura, D. Namikawa
We present multi-frequency simultaneous VLBA observations at 15, 22 and 43 GHz towards the nucleus of the nearby radio galaxy NGC 1052. These three continuum images reveal a double-sided jet structure, whose relative intensity ratios imply that the jet axis is oriented close to the sky plane. The steeply rising spectra at 15-43 GHz at the inner edges of the
Dawei Chen
A ribbon is a double structure on P^1. The geometry of a ribbon is closely related to that of a smooth curve. In this note we consider linear series on ribbons. Our main result is an explicit determinantal description for the locus W^{r}_{2n} of degree 2n line bundles with at least (r+1)-dimensional sections on a ribbon. We also discuss some results of Cliff
Peter J. Forrester, Christopher M. Ormerod
The distribution function for the first eigenvalue spacing in the Laguerre unitary ensemble of finite size may be expressed in terms of a solution of the fifth Painleve transcendent. The generating function of a certain discontinuous linear statistic of the Laguerre unitary ensemble can similarly be expressed in terms of a solution of the fifth Painleve equa
Clark Alexander
We construct Lie algebras arising from commutators of the harmonic Hamiltonian and the perturbed anharmonic Hamiltonian. From there we form a very specific element of the associated Lie group and transform the unperturbed Hamiltonian into the perturbed Hamiltonian minus perturbation energies. An explicit formula is given for the first order perturbation ener
Off-center collisions in AdS_5 with applications to multiplicity estimates in heavy-ion collisions
hep-thSteven S. Gubser, Silviu S. Pufu, Amos Yarom
We study the trapped surface produced by an off-center collision of light-like, point-sourced shock waves in anti-de Sitter space. We find an analytic expression for the shape of the trapped surface in the limit where the energy of the shock waves is large and the impact parameter is not too large. We use the area of the trapped surface to estimate a lower b
O. Rosas-Ortiz, N. Fernandez-Garcia, Sara Cruz y Cruz
After a pedagogical introduction to the concept of resonance in classical and quantum mechanics, some interesting applications are discussed. The subject includes resonances occurring as one of the effects of radiative reaction, the resonances involved in the refraction of electromagnetic waves by a medium with a complex refractive index, and quantum decayin
Ken Yamamoto, Yoshihiro Yamazaki
Some statistical properties of a network of two-Chinese-character compound words in Japanese language are reported. In this network, a node represents a Chinese character and an edge represents a two-Chinese-character compound word. It is found that this network has properties of "small-world" and "scale-free." A network formed by only Chines
Christopher J. Stockdale, Kurt W. Weiler, Nino Panagia, Richard A. Sramek
Prior to explosion, a supernova progenitor slowly loses significant amounts of its hydrogen envelope in a stellar wind. After the explosion, the blastwave interacts with this wind producing synchrotron emission. A year of radio observations allows us to probe the progenitor evolution for a thousand years. The EVLA and SKA would represent more than an order o
Iosif Pinelis
The well-known Bennett-Hoeffding bound for sums of independent random variables is refined, by taking into account truncated third moments, and at that also improved by using, instead of the class of all increasing exponential functions, the much larger class of all generalized moment functions f such that f and f" are increasing and convex. It is shown
Xiaoli Yan
Using multi-wavelength data of Hinode, a rapid rotation of a sunspot in active region NOAA 10930 is studied in detail. We found the extra-ordinary counterclockwise rotation of the sunspot with positive polarity before an X3.4 flare. From a series of vector magnetograms, it is found that the magnetic force lines highly sheared along the neutral line accompany
J. K. Freericks
The mapping of steady-state nonequilibrium dynamical mean-field theory from the lattice to the impurity is described in detail. Our focus is on the case with current flow under a constant dc electric field of arbitrary magnitude. In addition to formulating the problem via path integrals and functional derivatives, we also describe the distribution function d
M. V. Rybin, A. B. Khanikaev, M. Inoue, K. B. Samusev
We report the observation of a Fano resonance between continuum Mie scattering and a narrow Bragg band in synthetic opal photonic crystals. The resonance leads to a transmission spectrum exhibiting a Bragg dip with an asymmetric profile, which can be tunably reversed to a Bragg rise. The Fano asymmetry parameter is linked with the dielectric contrast between
N. Fernandez-Garcia, O. Rosas-Ortiz
Complex potentials are constructed as Darboux-deformations of short range, radial nonsingular potentials. They behave as optical devices which both refracts and absorbs light waves. The deformation preserves the initial spectrum of energies and it is implemented by means of a Gamow-Siegert function (resonance state). As straightforward example, the method is
Annamaria Donnarumma, Stefano Ettori, Massimo Meneghetti, Lauro Moscardini
We present new mass estimates of the galaxy cluster MS2137.3-2353, inferred from X-ray and strong lensing analyses. This cluster exhibits an outstanding strong lensing configuration and indicates a well-relaxed dynamical state, being most suitable for a mass reconstruction which combines both techniques. Despite this, several previous studies have claimed a
S. Boinepalli, D. B. Leinweber, P. J. Moran, A. G. Williams
The electromagnetic properties of the baryon decuplet are calculated in quenched QCD on a 20^3 x 40 lattice with a lattice spacing of 0.128 fm using the fat-link irrelevant clover (FLIC) fermion action with quark masses providing a pion mass as low as 300 MeV. Magnetic moments and charge radii are extracted from the electric and magnetic form factors for eac
M. Amin Khajehnejad, Alexandros G. Dimakis, Weiyu Xu, Babak Hassibi
We investigate the sparse recovery problem of reconstructing a high-dimensional non-negative sparse vector from lower dimensional linear measurements. While much work has focused on dense measurement matrices, sparse measurement schemes are crucial in applications, such as DNA microarrays and sensor networks, where dense measurements are not practically feas
C. S. Brinkworth, B. T. Gaensicke, T. R. Marsh, D. W. Hoard
We present ISAAC spectroscopy and ISAAC, UKIDSS and Spitzer Space Telescope broad-band photometry of SDSS J1228+1040 -- a white dwarf for which evidence of a gaseous metal-rich circumstellar disk has previously been found from optical emission lines. The data show a clear excess in the near- and mid-infrared, providing compelling evidence for the presence of
Beyond conventional factorization: Non-Hermitian Hamiltonians with radial oscillator spectrum
quant-phIvan Cabrera-Munguia, Oscar Rosas-Ortiz
The eigenvalue problem of the spherically symmetric oscillator Hamiltonian is revisited in the context of canonical raising and lowering operators. The Hamiltonian is then factorized in terms of two not mutually adjoint factorizing operators which, in turn, give rise to a non-Hermitian radial Hamiltonian. The set of eigenvalues of this new Hamiltonian is exa
Rokia Missaoui, Leonard Kwuida, Mohamed Quafafou, Jean Vaillancourt
The objectives of this research work which is intimately related to pattern discovery and management are threefold: (i) handle the problem of pattern manipulation by defining operations on patterns, (ii) study the problem of enriching and updating a pattern set (e.g., concepts, rules) when changes occur in the user's needs and the input data (e.g., objec
Steven S. Gubser, Silviu S. Pufu, Fabio D. Rocha, Amos Yarom
We review methods developed in the gauge-string duality to treat energy loss by energetic probes of a strongly coupled thermal medium. After introducing the black hole description of the thermal medium, we discuss the trailing string behind a heavy quark and the drag force that it implies. We then explain how to solve the linearized Einstein equations in the
V. Topor Pop, J. Barrette, M. Gyulassy
Effects of strong longitudinal color electric fields (SCF) on the open charm production in nucleus-nucleus (A + A) collisions at 200A GeV are investigated within the framework of the HIJING-BBbar v2.0 model. A three fold increase of the effective string tension due to in medium effects in A + A collisions, results in a sizeable (60-70 percents) enhancement o
D. Froebrich, H. Meusinger, C. J. Davis, S. Schmeja
We aim to characterise the properties of the stellar clusters in the Milky Way. Utilising an expectation-maximisation method we determined that the cluster FSR0358, originally discovered by J.D.Kirkpatrick, is the most likely real cluster amongst the cluster candidates from Froebrich et al.. Here we present new deep high resolution near infrared imaging of t
Balt C. van Rees
In arXiv:0805.0150 [hep-th] and arXiv:0812.2909 [hep-th] a general prescription was presented for the computation of real-time correlation functions using the gauge/gravity duality. I apply this prescription to the specific case of retarded thermal correlation functions and derive the usual ingoing boundary conditions at the horizon for bulk fields. The deri
A. Gumann, C. Iniotakis, N. Schopohl
Josephson junctions with an intrinsic phase shift of pi, so-called pi Josephson junctions, can be realized by a weak link of a d-wave superconductor with an appropriate boundary geometry. A model for the pairing potential of an according weak link is introduced which allows for the calculation of the influence of geometric parameters and temperature. From th
Samuel Coskey, Paul Ellis, Scott Schneider
We prove that the conjugacy problem for the automorphism group of the random graph is Borel complete, and discuss the analogous problem for some other countably categorical structures.
Takeshi Chiba
We derive slow-roll conditions for thawing quintessence. We solve the equation of motion of $ϕ$ for a Taylor expanded potential (up to the quadratic order) in the limit where the equation of state $w$ is close to -1 to derive the equation of state as a function of the scale factor. We find that the evolution of $ϕ$ and hence $w$ are described by only two par
Kingman Cheung, Po-Yan Tseng, Tzu-Chiang Yuan
Motivated by a two-bump (or 1-peak plus 1-hump) structure in the ATIC data, we perform a statistical analysis fitting the PAMELA and ATIC data to a dark matter model, in which the dark matter particle can undergo both annihilation and decay. Using a chi-square analysis we show that both data can be simultaneously fitted better with such a double-action dark
Dumitru Astefanesei, Yogesh K. Srivastava
In this paper we generalize the results of [1] to 5-dimensional Anti-de Sitter gravity theories with neutral scalars non-minimally coupled to gauge fields. Due to the attractor mechanism, the near horizon geometry of extremal black holes is universal and is determined by only the charge parameters. In particular, we study a class of near horizon geometries t
Luis Caffarelli, Luis Silvestre
In this paper we prove a nonlocal version of the Cordes-Niremberg estimates. We use it to extend our previous regularity results for fully nonlinear integro-differential equations to the variable coefficient case and several other settings where the equation can be thought of as a perturbation of the translation invariant case.
G. de Berredo-Peixoto, E. A. de Freitas
In this work we investigate the effects of torsion in the framework of Einstein-Cartan theory in early cosmology. We study solutions for a homogeneous and isotropic relativistic Weyssenhoff spin fluid with dynamical timelike axial current, also homogeneous and isotropic. The general solutions can mostly be described by means of three particular solutions. Th
Christina Aragona, M. Virginia McSwain, Erika D. Grundstrom, Amber N. Marsh
LS I +61 303 and LS 5039 are two of only a handful of known high mass X-ray binaries (HMXBs) that exhibit very high energy emission in the MeV-TeV range, and these "gamma-ray binaries" are of renewed interest due to the recent launch of the Fermi Gamma-ray Space Telescope. Here we present new radial velocities of both systems based on recent red and
A Cross-Correlation Analysis of Mg II Absorption Line Systems and Luminous Red Galaxies from the SDSS DR5
astro-ph.COBritt F. Lundgren, Robert J. Brunner, Donald G. York, Ashley J. Ross
We analyze the cross-correlation of 2,705 unambiguously intervening Mg II (2796,2803A) quasar absorption line systems with 1,495,604 luminous red galaxies (LRGs) from the Fifth Data Release of the Sloan Digital Sky Survey within the redshift range 0.36<=z<=0.8. We confirm with high precision a previously reported weak anti-correlation of equivalent width and
Alexandru Chirvasitu
Given a complete, cocomplete category $\mathcal C$, we investigate the problem of describing those small categories $I$ such that the diagonal functor $Δ:\mathcal C\to {\rm Functors}(I,\mathcal C)$ is a Frobenius functor. This condition can be rephrased by saying that the limits and the colimits of functors $I\to\mathcal C$ are naturally isomorphic. We find
Einar Steingrimsson, Bridget Eileen Tenner
A permutation τcontains another permutation σas a pattern if τhas a subsequence whose elements are in the same order with respect to size as the elements in σ. This defines a partial order on the set of all permutations, and gives a graded poset P. We give a large class of pairs of permutations whose intervals in P have Mobius function 0. Also, we give a sol
High-field muSR studies of superconducting and magnetic correlations in cuprates above Tc
cond-mat.supr-conJ. E. Sonier
The advent of high transverse-field muon spin rotation (TF-muSR) has led to recent muSR investigations of the magnetic-field response of cuprates above the superconducting transition temperature T_c. Here the results of such experiments on hole-doped cuprates are reviewed. Although these investigations are currently ongoing, it is clear that the effects of h
Daisuke Kawata, Takashi Okamoto, Brad K. Gibson, David J. Barnes
We adapt a modern scheme of smoothed particle hydrodynamics (SPH) to our tree N-body/SPH galactic chemodynamics code GCD+. The applied scheme includes imple- mentations of the artificial viscosity switch and artificial thermal conductivity pro- posed by Morris & Monaghan (1997), Rosswog & Price (2007) and Price (2008), to model discontinuities and Kelvin-Hel
Tobias Bruch, Annika H. G. Peter, Justin Read, Laura Baudis
As disc galaxies form in a hierarchical cosmology, massive merging satellites are preferentially dragged towards the disc plane. The material accreted from these satellites forms a dark matter disc that contributes 0.25 - 1.5 times the non-rotating halo density at the solar position. Here, we show the importance of the dark disc for indirect dark matter dete
David S. Spiegel, Katie Silverio, Adam Burrows
Spitzer Space Telescope infrared observations indicate that several transiting extrasolar giant planets have thermal inversions in their upper atmospheres. Above a relative minimum, the temperature appears to increase with altitude. Such an inversion probably requires a species at high altitude that absorbs a significant amount of incident optical/UV radiati
Coupled Evolution with Tides of the Radius and Orbit of Transiting Giant Planets: General Results
astro-ph.EPLaurent Ibgui, Adam Burrows
Some transiting extrasolar giant planets have measured radii larger than predicted by the standard theory. In this paper, we explore the possibility that an earlier episode of tidal heating can explain such radius anomalies and apply the formalism we develop to HD 209458b as an example. We find that for strong enough tides the planet's radius can undergo
Tomohiro Abe, R. Sekhar Chivukula, Neil D. Christensen, Ken Hsieh
In this note we compute the flavor-dependent chiral-logarithmic corrections to the decay Z to b bbar in the three site Higgsless model. We compute these corrections diagrammatically in the "gaugeless" limit in which the electroweak couplings vanish. We also compute the chiral-logarithmic corrections to the decay Z to b bbar using an RGE analysis in e
Diego Bombardelli, Davide Fioravanti, Roberto Tateo
Moving from the mirror theory Bethe-Yang equations proposed by Arutyunov and Frolov, we derive the thermodynamic Bethe Ansatz equations which should control the spectrum of the planar $\text{AdS}_5/\text{CFT}_4$ correspondence. The associated set of universal functional relations (Y-system) satisfied by the exponentials of the TBA pseudoenergies is deduced,
Vassilis Koukouloyannis, Panayotis G. Kevrekidis
In the present paper, a theorem, which determines the linear stability of multibreathers in Klein-Gordon chains, is proven. Specifically, it is shown that for soft nonlinearities, and positive inter-site coupling, only structures with adjacent sites excited out-of-phase may be stable, while only in-phase ones may be stable for negative coupling. The situatio
Marc Favata
Some astrophysical sources of gravitational waves can produce a "memory effect," which causes a permanent displacement of the test masses in a freely falling gravitational-wave detector. The Christodoulou memory is a particularly interesting nonlinear form of memory that arises from the gravitational-wave stress-energy tensor's contribution to th
Ryszard Nest, Christian Voigt
We extend the notion of Poincaré duality in KK-theory to the setting of quantum group actions. An important ingredient in our approach is the replacement of ordinary tensor products by braided tensor products. Along the way we discuss general properties of equivariant KK-theory for locally compact quantum groups, including the construction of exterior produc
Petr Horava
We extend the definition of "spectral dimension" (usually defined for fractal and lattice geometries) to theories on smooth spacetimes with anisotropic scaling. We show that in quantum gravity dominated by a Lifshitz point with dynamical critical exponent z in D+1 spacetime dimensions, the spectral dimension of spacetime is equal to d_s=1+D/z. In the
Wojciech H. Zurek
Symmetry breaking during phase transitions can lead to the formation of topological defects (such as vortex lines in superfluids). However, the usually studied BEC's have the shape of a cigar, a geometry that impedes vortex formation, survival, and detection. I show that, in elongated traps, one can expect the formation of "grey solitons" (long-l
Azer Akhmedov
We present new metric criteria for non-amenability and discuss applications. The main application of the results of this paper is the proof of non-amenability of R.Thompson's group F. This is a continuation of the series of papers on our criteria for non-amenability. The current paper is independent of other papers in the series.
Emmanuel N. Saridakis
We investigate phantom models with power-law potentials and we extract the early-time, "tracker", solutions under the assumption of matter domination. Contrary to quintessence case, we find that energy positivity requires normal power-law potentials instead of inverse power-law ones, with the potential exponent being bounded by the quadratic form. In
Sylvain Arlot, Alain Celisse
This paper tackles the problem of detecting abrupt changes in the mean of a heteroscedastic signal by model selection, without knowledge on the variations of the noise. A new family of change-point detection procedures is proposed, showing that cross-validation methods can be successful in the heteroscedastic framework, whereas most existing procedures are n
Sara Cruz y Cruz, Oscar Rosas-Ortiz
The Schroedinger equation for position-dependent mass singular oscillators is solved by means of the factorization method and point transformations. These systems share their spectrum with the conventional singular oscillator. Ladder operators are constructed to close the su(1,1) Lie algebra and the involved point transformations are shown to preserve the st
Gouranga C Nayak
According to string theory, string ball is a highly excited long string which decays to standard model particles at the Hagedorn temperature with thermal spectrum. If there are extra dimensions, the string scale can be $\sim$ TeV, and we should produce string balls at CERN LHC. In this paper we study top quark production from string balls at LHC and compare