February 2005 arXiv papers — page 2
Showing 101–200 of 3,262 papers
Klara Elteto, Xiao-Min Lin, Heinrich M. Jaeger
We report on the fabrication and current-voltage (IV) characteristics of very narrow, strip-like arrays of metal nanoparticles. The arrays were formed from gold nanocrystals self-assembled between in-plane electrodes. Local cross-linking of the ligands by exposure to a focused electron beam and subsequent removal of the unexposed regions produced arrays as n
Magnetic and superconducting properties of RuSr2 Gd1.5Ce0.5Cu2O10-x samples: dependence on the oxygen content and ageing effects
cond-mat.supr-conC. A. Cardoso, A. J. C. Lanfredi, A. J. Chiquito, V. P. S. Awana
The magnetic and superconducting properties of RuSr2Gd1.5Ce0.5Cu2O10-x polycrystalline samples with different oxygen doping level are presented. A strong suppression of the superconducting temperature (Tc), as well as a reduction in the superconducting fraction, occurs as the oxygen content is reduced by annealing the samples in oxygen deprived atmospheres.
E. I. Kats, A. R. Muratov
We investigate vibrational excitation broadening in one dimensional Fibonacci model of quasicrystals (QCs). The chain is constructed from particles with two masses following the Fibonacci inflation rule. The eigenmode spectrum depends crucially on the mass ratio. We calculate the eigenstates and eigenfunctions. All calculations performed self-consistently wi
Seung-Woo Son, Hawoong Jeong, Jae Dong Noh
We propose a method to find out the community structure of a complex network. In this method the ground state problem of a ferromagnetic random field Ising model is considered on the network with the magnetic field $B_s = +\infty$, $B_{t} = -\infty$, and $B_{i\neq s,t}=0$ for a node pair $s$ and $t$. The ground state problem is equivalent to the so-called ma
Adsorption-Induced Distortion of F_{16}CuPc on Cu(111) and Ag(111): An X-ray Standing Wave Study
cond-mat.softA. Gerlach, F. Schreiber, S. Sellner, H. Dosch
The adsorption geometry of perfluorinated copper-phthalocyanine molecules (F_{16}CuPc) on Cu(111) and Ag(111) is studied using X-ray standing waves. A detailed, element-specific analysis taking into account non-dipolar corrections to the photoelectron yield shows that on both surfaces the molecules adsorb in a lying down, but significantly distorted configur
Olivier Pouliquen
Velocity fluctuations of grains flowing down a rough inclined plane are experimentally studied. The grains at the free surface exhibit fluctuating motions, which are correlated over few grains diameters. The characteristic correlation length is shown to depend on the inclination of the plane and not on the thickness of the flowing layer. This result strongly
Can Finite Size Effects in the Poland-Scheraga Model Explain Simulations of a Simple Model for DNA Denaturation ?
cond-mat.stat-mechLothar Schäfer
We compare results of previous simulations of a simple model of DNA denaturation to the predictions of the Poland-Scheraga model. Concentrating on the critical region of the latter model we calculate both thermodynamic quantities and the distribution functions measured in the simulations. We find that the Poland-Scheraga model yields an excellent fit to the
Structural matters in HTSC; the origin and form of stripe organization and checker boarding
cond-mat.supr-conJohn A. Wilson
The paper deals with the controversial charge and spin self-organization phenomena in the HTSC cuprates, of which neutron, X-ray, STM and ARPES experiments give complementary, sometimes apparently contradictory glimpses. The examination has been set in the context of the boson-fermion, negative-U understanding of HTSC advocated over many years by the author.
M. C. Gonzalez, H. J. Herrmann, A. D. Araujo
Clusters of infected individuals are defined on data from health laboratories, but this quantity has not been defined and characterized by epidemy models on statistical physics. For a system of mobile agents we simulate a model of infection without immunization and show that all the moments of the cluster size distribution at the critical rate of infection a
C. Sauvan, P. Lalanne, J. P. Hugonin
Physical mechanisms involved in the light confinement in photonic crystal slab microcavities are investigated. We first present a full three-dimensional numerical study of these microcavities. Then, to gain physical insight into the confinement mechanisms, we develop a Fabry-Perot model. This model provides accurate predictions and sheds new light on the phy
Agata Fronczak, Piotr Fronczak, Janusz A. Holyst
We present an analytic formalism describing structural properties of random uncorrelated networks with arbitrary degree distributions. The formalism allows to calculate the main network characteristics like: the position of the phase transition at which a giant component first forms, the mean component size below the phase transition, the size of the giant c
Oleg V. Dolgov, Reinhard K. Kremer, Jens Kortus, Alexander A. Golubov
Thermodynamic properties of the multiband superconductor MgB$_{2}$ have often been described using a simple sum of the standard BCS expressions corresponding to $σ$- and $π$-bands. Although, it is \textit{a priori} not clear if this approach is working always adequately, in particular in cases of strong interband scattering. Here we compare the often used ap
Dynamical density functional theory: binary phase-separating colloidal fluid in a cavity
cond-mat.softA. J. Archer
The dynamical density functional theory of Marconi and Tarazona [J. Chem. Phys., 110, 8032 (1999)], a theory for the non-equilibrium dynamics of the one-body density profile of a colloidal fluid, is applied to a binary fluid mixture of repulsive Gaussian particles confined in a spherical cavity of variable size. For this model fluid there exists an extremely
M. Houzet, D. A. Pesin, A. V. Andreev, L. I. Glazman
We consider charge quantization in a small superconducting grain that is contacted by a normal-metal electrode and is controlled by a capacitively coupled gate. At zero temperature and zero conductance $G$ between the grain and the electrode, the charge $Q$ as a function of the gate voltage $V_g$ changes in steps. The step height is $e$ if $Δ<E_c$, where $Δ$
Current Dissipation in Thin Superconducting Wires: Accurate Numerical Evaluation Using the String Method
cond-mat.supr-conTiezheng Qian, Weiqing Ren, Ping Sheng
Current dissipation in thin superconducting wires is numerically evaluated by using the string method, within the framework of time-dependent Ginzburg-Landau equation with a Langevin noise term. The most probable transition pathway between two neighboring current-carrying metastable states, continuously linking the Langer-Ambegaokar saddle-point state to a s
Simulation of the transient photocurrent response of polycrystalline photocells based on equivalent circuit analysis
cond-mat.mtrl-sciB. Vainas
We propose an equivalent circuit representation of the photogenerated charge separation and propagation in dye sensitized polycrystalline semiconductor in contact with a redox electrolyte. The suggested equivalent circuit for this type of photocell is based on an electrical transmission-line, and uses distributed photodiode model for the semiconductor-redox
Nonlinear rheology of dense colloidal dispersions: a phenomenological model and its connection to mode coupling theory
cond-mat.softMatthias Fuchs, Matthias Ballauff
Rheological properties, especially 'shear-thinning', of dense colloidal dispersions are discussed on three different levels. A generalized phenomonological Maxwell model gives a broad framework connecting glassy dynamics to the linear and non-linear rheology of dense amorphous particle solutions. First principles mode coupling theory calculations for
Magdalena Marganska, Marek Szopa, Elzbieta Zipper
The unusual band structure of carbon nanotubes (CNs) results in their remarkable magnetic properties. The application of magnetic field parallel to the tube axis can change the conducting properties of the CN from metallic to semiconducting and vice versa. Apart from that B induces (via the Bohm-Aharonov effect) orbital magnetic moments $μ_{orb}$ in the nano
Energy dependent sputtering of nano-clusters from a nanodisperse target and embedding of nanoparticles into a substrate
cond-mat.mtrl-sciB. Satpati, J. Ghatak, B. Joseph, P. V. Satyam
Au nanoparticles, prepared by thermal evaporation under high vacuum condition on Si substrate, are irradiated with Au ions at different ion energies. During ion irradiation, embedding of nanoparticles as well as ejection of nano-clusters is observed. Ejected particles (usually smaller than those on the Si substrate) due to sputtering are collected on carbon-
Finite electron crystallites in strong magnetic fields: Precursors of a supersolid?
cond-mat.mes-hallYuesong Li, Constantine Yannouleas, Uzi Landman
We show that a supersolid phase, exhibiting simultaneously solid and superfluid behavior, properly describes the finite electron crystallites that form in two-dimensional quantum dots under high magnetic fields. These crystallites rotate already in their ground state and exhibit a nonclassical rotational inertia. They are precursors to a supersolid crystal i
Some formal properties on superstatistics and superposition of statistical factors
cond-mat.stat-mechTakuya Yamano
By focusing on the interchangeable role in a generating function (i.e., $β\leftrightarrow E$ in the Laplace transform), the superstatistics proposed by Beck and Cohen can be viewed as a counterpart of the canonical partition function. Some formal properties of this superstatistics are presented in connection with thermodynamic structures and information aspe
Reversible and irreversible trapping at room temperature in poly(thiophene) thin-film transistors
cond-mat.mtrl-sciA. Salleo, F. Endicott, R. A. Street
We measured the bias stress characteristics of poly(thiophene) semi-crystalline thin-film transistors (TFTs) as a function stress times, gate voltages and duty-cycles. At room temperature, the bias stress has two components: a fast reversible component and a slow irreversible component. We hypothesize that the irreversible component is due to charge trapping
Egor Babaev
We discuss a novel type of fractional flux vortices along with integer flux vortices in Kosterlitz-Thouless transitions in a triplet superconductor. We show that under certain conditions a spin-triplet superconductor should exhibit a novel state of {\it spin superfluidity} without superconductivity.
C. R. Mullis, P. Rosati, G. Lamer, H. Boehringer
We report the discovery of a massive, X-ray-luminous cluster of galaxies at z=1.393, the most distant X-ray-selected cluster found to date. XMMU J2235.3-2557 was serendipitously detected as an extended X-ray source in an archival XMM-Newton observation of NGC 7314. VLT-FORS2 R and z band snapshot imaging reveals an over-density of red galaxies in both angula
Asantha Cooray, Marc Kamionkowski, Robert R. Caldwell
Weak-lensing distortions of the cosmic-microwave-background (CMB) temperature and polarization patterns can reveal important clues to the intervening large-scale structure. The effect of lensing is to deflect the primary temperature and polarization signal to slightly different locations on the sky. Deflections due to density fluctuations, gradient-type for
John J. Cowan, Christopher Sneden, Timothy C. Beers, James E. Lawler
We present new abundance determinations of neutron-capture elements Ge, Zr, Os, Ir, and Pt in a sample of 11 metal-poor (-3.1 <= [Fe/H] <= -1.6) Galactic halo giant stars, based on Hubble Space Telescope UV and Keck I optical high-resolution spectroscopy. The stellar sample is dominated by r-process-rich stars such as the well-studied CS 22892-052 and bd+173
D. T. Frayer
Early results from the 70-micron observations of the Spitzer Extragalactic First Look Survey are presented. As a whole, about 90% of the population show infrared colors that are consistent with the spectral energy distributions of the local IRAS population of luminous infrared starbursts, while approximately 10% of the sample show warm infrared colors consis
David J. Mulryne, Reza Tavakol, James E. Lidsey, George F. R. Ellis
Closed, singularity-free, inflationary cosmological models have recently been studied in the context of general relativity. Despite their appeal, these so called emergent models suffer from a number of limitations. These include the fact that they rely on an initial Einstein static state to describe the past eternal phase of the universe. Given the instabili
Carl R. Brune
Nuclear physics has a long and productive history of application to astrophysics which continues today. Advances in the accuracy and breadth of astrophysical data and theory drive the need for better experimental and theoretical understanding of the underlying nuclear physics. This paper will review some of the scenarios where nuclear physics plays an import
S. J. Lipscy, M. Jura, M. J. Reid
We have used the VLA to detect emission from the supergiant VY CMa at radio wavelengths and have constructed 3000-4500 K isothermal outer atmospheres constrained by the data. These models produce a radio photosphere at 1.5-2 R_ast. An extrapolation of the model can account for the observed total mass-loss rate of the star. We also present mid-infrared imagin
L. M. Freyhammer, M. Monelli, G. Bono, P. Cunti
We present three different optical and near-infrared (NIR) data sets for evolved stars in the Galactic Globular Cluster Omega Cen The comparison between observations and homogeneous sets of stellar isochrones and Zero-Age Horizontal Branches provides two reasonable fits. Both of them suggest that the so-called anomalous branch has a metal-intermediate chemic
On the existence of three-dimensional hydrostatic and magnetostatic equilibria of self-gravitating fluid bodies
astro-phDaniele Galli
(Abridged) We develop an analytical spectral method to solve the equations of equilibrium for a self-gravitating, magnetized fluid body, under the only hypotheses that (a) the equation of state is isothermal, (b) the configuration is scale-free, and (c) the body is electrically neutral. All physical variables are represented as series of scalar and vector sp
M. M. Roth, A. Kelz, T. Fechner, T. Hahn
We describe the design, manufacture, commissioning, and performance of PMAS, the Potsdam Multi-Aperture Spectrophotometer. PMAS is a dedicated integral field spectrophotometer, optimized to cover the optical wavelength regime of 0.35--1um. It is based on the lens array -- fiber bundle principle of operation. The instrument employs an all-refractive fiber spe
A. L. B. Ribeiro, J. G. Peixoto de Faria
We use the weakly nonlocal hydrodynamics approach to obtain a dynamical equation for the peculiar velocity field in which the viscosity term is physically motivated. Based on some properties of the Ginzburg-Landau equation and the wave mechanics analog of hydrodynamics we find the nonlocal adhesion approximation taking into account the internal structures of
George Voyatzis, Thomas Kotoulas
In the framework of the planar restricted three body problem we study a considerable number of resonances associated to the Kuiper Belt dynamics and located between 30 and 48 a.u. Our study is based on the computation of resonant periodic orbits and their stability. Stable periodic orbits are surrounded by regular librations in phase space and in such domain
H. Grigorian
The cooling of compact isolated objects for different values of the gravitational mass has been simulated for two alternative assumptions. One is that the interior of the star is purely hadronic and second that the star can have a rather large quark core. It has been shown that within a nonlocal chiral quark model the critical density for a phase transition
M. J. Hardcastle, I. Sakelliou, D. M. Worrall
We have observed the prototypical wide-angle tail radio galaxy 3C465 with Chandra and XMM-Newton. X-ray emission is detected from the active nucleus and the inner radio jet, as well as a small-scale, cool component of thermal emission, a number of the individual galaxies of the host cluster (Abell 2634), and the hotter thermal emission from the cluster itsel
Kate Land, Joao Magueijo
We investigate the Statistical Isotropy and Gaussianity of the CMB fluctuations, using a set of multipole vector functions capable of separating these two issues. In general a multipole is broken into a frame and $2\ell-3$ ordered invariants. The multipole frame is found to be suitably sensitive to galactic cuts. We then apply our method to real WMAP dataset
Supermassive black hole mass measurements for NGC 1300 and NGC 2748 based on HST emission-line gas kinematics
astro-phJ. W. Atkinson, J. L. Collett, A. Marconi, D. J. Axon
We present Space Telescope Imaging Spectrograph emission-line spectra of the central regions of the spiral galaxies NGC 1300 and NGC 2748. From the derived kinematics of the nuclear gas we have found evidence for central supermassive black holes in both galaxies. The estimated mass of the black hole in NGC 1300 is 6.6 (+6.3, -3.2) x 10^7 solar masses and in
E. Pointecouteau, M. Arnaud, G. W. Pratt
We present results based on XMM-Newton observations of a small sample of hot galaxy clusters. Making a full use of XMM-Newton's spectro-imaging capabilities, we have extracted the radial temperature profile and gas density profile, and with this information, calculated the total mass profile of each cluster (under the assumption of hydrostatic equilibriu
A. R. King
I briefly review magnetic effects in accretion physics, and then go on to discuss a possible central engine for gamma-ray bursts. A rotating black hole immersed in a non-axisymmetric magnetic field experiences a torque trying to align spin and field. I suggest that gamma-ray burst hosts may provide conditions where this effect allows rapid extraction of a si
Observational evidence for the presence of PAHs in distant Luminous Infrared Galaxies using ISO and Spitzer
astro-phD. Elbaz, E. Le Floc'h, H. Dole, D. Marcillac
We present ISOCAM 15 micron and MIPS 24 micron photometry of a sample of 16 distant Luminous Infrared Galaxies (LIRGs) characterized by a median luminosity L(IR) 2x10^11 Lsol and redshift z = 0.7 (distributed from z = 0.1 to 1.2). While some sources display 24/15 micron flux ratios also consistent with a featureless continuum dominating their mid-infrared (M
C. S. Stalin, R. Srianand
We report optical Cousins R and I band monitoring observations of the high redshift (z = 4.67) QSO SDSS J153259.96-003944.1 that does not show detectable emission lines in its optical spectrum. We show this object varies with a maximum amplitude of ~0.4 mag during a year and three months of monitoring. Combined with two other epochs of photometric data avail
Towards a deterministic model of planetary formation. III. Mass distribution of short-period planets around stars of various masses
astro-phS. Ida, D. N. C. Lin
The origin of a recently discovered close-in Neptune-mass planet around GJ436 poses a challenge to the current theories of planet formation. Based on the sequential accretion hypothesis and the standard theory of gap formation and orbital migration, we show that around M dwarf stars, close-in Neptune-mass ice-giant planets may be relatively common, while clo
Qirong Yuan, Pengfei Yan, Yanbin Yang, Xu Zhou
Convincing evidence of a past interaction between two rich clusters A399 and A401 was recently found by the X-ray imaging observations. In this paper we examine the structure and dynamics of this pair of galaxy clusters. A mixture-modeling algorithm has been applied to obtain a robust partition into two clusters, which allows us to discuss the virial mass an
Andrei Gruzinov
We speculate that stationary force-free pulsar magnetospheres are screw unstable, and the spin-down power of real pulsars is carried by turbulent Poynting jets. The turbulent jet entrains poloidal flux as it propagates away from the star. Due to poloidal flux entrainment, poloidal field inside the jet decreases at a slower rate than the dipole's $r^{-3}$
V. Berezinsky, A. Z. Gazizov, S. I. Grigorieva
Ultrahigh energy (UHE) extragalactic protons propagating through cosmic microwave radiation (CMB) acquire the spectrum features in the form of the dip, bump (pile-up protons) and the Greisen-Zatsepin-Kuzmin (GZK) cutoff. We have performed the analysis of these features in terms of the modification factor. This analysis is weakly model-dependent, especially i
Cosmic 21-cm Delensing of Microwave Background Polarization and the Minimum Detectable Energy Scale of Inflation
astro-phKris Sigurdson, Asantha Cooray
The curl (B) modes of cosmic microwave background (CMB) polarization anisotropies are a unique probe of the primordial background of inflationary gravitational waves (IGWs). Unfortunately, the B-mode polarization anisotropies generated by gravitational waves at recombination are confused with those generated by the mixing of gradient-mode (E-mode) and B-mode
Gravitational Radiation from Coalescing Supermassive Black Hole Binaries in a Hierarchical Galaxy Formation Model
astro-phMotohiro Enoki, Kaiki T. Inoue, Masahiro Nagashima, Naoshi Sugiyama
We investigate the expected gravitational wave emission from coalescing supermassive black hole (SMBH) binaries resulting from mergers of their host galaxies. We employ a semi-analytic model of galaxy and quasar formation based on the hierarchical clustering scenario to estimate the amplitude of the expected stochastic gravitational wave background owing to
Oleksiy Khorunzhiy, Werner Kirsch, Peter Müller
We consider the discrete Laplace operator $Δ^{(N)}$ on Erdős--Rényi random graphs with $N$ vertices and edge probability $p/N$. We are interested in the limiting spectral properties of $Δ^{(N)}$ as $N\to\infty$ in the subcritical regime $0<p<1$ where no giant cluster emerges. We prove that in this limit the expectation value of the integrated density of stat
Nathan M. Dunfield, William P. Thurston
A 3-manifold is Haken if it contains a topologically essential surface. The Virtual Haken Conjecture posits that every irreducible 3-manifold with infinite fundamental group has a finite cover which is Haken. In this paper, we study random 3-manifolds and their finite covers in an attempt to shed light on this difficult question. In particular, we consider r
Ce Meng, Ying-Jia Gao, Kuang-Ta Chao
We study the unexpectedly large rate for the factorization-forbidden decay $B\to \chi_{c0}K$ within the QCD factorization approach. We use a non-zero gluon mass to regularize the infrared divergences in vertex corrections. The end-point singularities arising from spectator corrections are regularized and carefully estimated by the off-shellness of quarks. We
Jeffrey R. Weeks
Observational data hints at a finite universe, with spherical manifolds such as the Poincare dodecahedral space tentatively providing the best fit. Simulating the physics of a model universe requires knowing the eigenmodes of the Laplace operator on the space. The present article provides explicit polynomial eigenmodes for all globally homogeneous 3-manifold
Spectrophotometry of Sextans A and B: Chemical Abundances of HII Regions and Planetary Nebulae
astro-phAlexei Y. Kniazev, Eva K. Grebel, Simon A. Pustilnik, Alexander G. Pramskij
We present the results of high quality long-slit spectroscopy of planetary nebulae (PNe) and HII regions in the two dwarf irregular galaxies Sextans A and B, which belong to a small group of galaxies just outside the Local Group. In Sextans A we obtained the element abundances in its only known PN and in three HII regions with the classical Te method. The ox
Sharmanthie Fernando
In this paper we investigate the perturbations by a massless Dirac spinor of a Born-Infeld black hole. The decay rates of the spinor field which is given by the quasinormal mode frequencies are computed using the sixth order WKB approximation. The behavior of the quasi normal modes with the non-linear parameter, temperature and charge of the black hole are a
E. Erturk, O. Gokcol
Numerical solutions of 2-D steady incompressible flow inside a triangular cavity are presented. For the purpose of comparing our results with several different triangular cavity studies with different triangle geometries, a general triangle mapped onto a computational domain is considered. The Navier-Stokes equations in general curvilinear coordinates in str
Hervé Brönnimann, Olivier Devillers, Sylvain Lazard, Frank Sottile
We investigate the lines tangent to four triangles in R^3. By a construction, there can be as many as 62 tangents. We show that there are at most 162 connected components of tangents, and at most 156 if the triangles are disjoint. In addition, if the triangles are in (algebraic) general position, then the number of tangents is finite and it is always even.
C. Chicone, B. Mashhoon
Imagine a swarm of free particles near a point P outside a gravitating mass M and a free reference particle at P that is on a radial escape trajectory away from M. Relative to this reference particle and in a Fermi normal coordinate system constructed along its worldline, the particles in the swarm that move along the radial direction and are ultrarelativist
Kevin Cahill
Identical objects, regularly assembled, form a helix, which is the principal motif of nucleic acids, proteins, and viral capsids.
Andrew S. Friedman, Joshua S. Bloom
Following our previous work, we conclude that a GRB standard candle constructed from the Ghirlanda et al. power-law relation between the geometry-corrected energy (E_gamma) and the peak of the rest-frame prompt burst spectrum (E_p) is not yet cosmographically useful, despite holding some potential advantages over SNe Ia. This is due largely to the small samp
Nicholas Peters, Joseph Altepeter, Evan Jeffrey, David Branning
We present the theoretical basis for and experimental verification of arbitrary single-qubit state generation, using the polarization of photons generated via spontaneous parametric downconversion. Our precision measurement and state reconstruction system has the capability to distinguish over 3 million states, all of which can be reproducibly generated usin
A Multifractal Detrended Fluctuation Description of Iranian Rial-US Dollar Exchange Rate
physics.data-anP. Norouzzadeh
The miltifractal properties and scaling behaviour of the exchange rate variations of the Iranian rial against the US dollar from a daily perspective is numerically investigated. For this purpose the multifractal detrended fluctuation analysis (MF-DFA) is used. Through multifractal analysis, the scaling exponents, generalized Hurst exponents, generalized frac
A. N. Kvinikhidze, B. Blankleider
We derive practical three-body equations for the equal-time three-body Green function in matter. Our equations describe both bosons and fermions at finite density and temperature, and take into account all possible two-body sub-processes allowed by the underlying Hamiltonian.
Jen-Hsu Chang
We investigate the reductions of dispersionless Harry Dym hierarchy to systems of finitely many partial differential equations. These equations must satisfy the compatibility condition and they are diagonalizable and semi-Hamiltonian. By imposing a further constraint, the compatibility is reduced to a system of algebraic equations, whose solutions are descri
Hiroyuki Kitahata, Ryoichi Aihara, Yoshihito Mori, Kenichi Yoshikawa
The propagation of a chemical wave in a narrow, cone-shaped glass capillary was investigated. When a chemical wave propagates from the wider end to the narrower end, it slows, stops, and then disappears. A phenomenological model that considers the surface effect of the glass is proposed, and this model reproduces the experimental trends.
A. G. Ramm
It is proved that the measurement of the acoustic pressure on the ear membrane allows one to determine the shape of the ear channel uniquely.
Emily Shores
We prove that if u is a weak solution to a constant coefficient system (with strong ellipticity assumed along the horizontal direction) in a Carnot group (no restriction on the step), then u is actually smooth. We then use this result to develop blow-up analysis to prove a partial regularity result for weak solutions of certain non-linear systems.
Semi-classical spectral estimates for Schrödinger operators at a critical level. Case of a degenerate maximum of the potential
math.SPBrice Camus
We study the semi-classical trace formula at a critical energy level for a Schrödinger operator on $\mathbb{R}^{n}$. We assume here that the potential has a totally degenerate critical point associated to a local maximum. The main result, which establishes the contribution of the associated equilibrium in the trace formula, is valid for all time in a compact
Spencer Bloch, Hélène Esnault
We consider correspondences on smooth quasiprojective varieties $U$. An algebraic cycle inducing the Künneth projector onto $H^1(U)$ is constructed. Assuming normal crossings at infinity, the existence of relative motivic cohomology is shown to imply the independence of $\ell$ for traces of open correspondences.
Khovanov-Jacobsson numbers and invariants of surface-knots derived from Bar-Natan's theory
math.GTKokoro Tanaka
Khovanov introduced a cohomology theory for oriented classical links whose graded Euler characteristic is the Jones polynomial. Since Khovanov's theory is functorial for link cobordisms between classical links, we obtain an invariant of a surface-knot, called the {\it Khovanov-Jacobsson number}, by considering the surface-knot as a link cobordism between
Nicholas J. Proudfoot
This is an expository paper in which we define projective GIT quotients and introduce toric varieties from this perspective. It is intended primarily for readers who are learning either invariant theory or toric geometry for the first time.
Paolo Ghiggini
In this article we provide an infinite family of weakly symplectically fillable contact structures with trivial Ozsvath-Szabo contact invariants over Z/2Z. As a consequence of this fact, we show how Heegaard-Floer theory can distinguish between weakly and strongly fillable contact structures.
Pavlos Pasipoularides
In Refs. [3,1] two different approaches have been developed for the numerical computation of the effective energy in the presence of a magnetic flux tube, by using the phase shift method. However, the opinion has been expressed that these two variations of the phase shift method are not equivalent. In this paper we aim to solve this ambiguity by comparing th
Taejin Lee, Gordon W. Semenoff
A free fermion representation of the rolling tachyon boundary conformal field theory is constructed. The representation is used to obtain an explicit, compact, exact expression for the boundary state. We use the boundary state to compute the disc and cylinder amplitudes for the half-S-brane.
Subhendra Mohanty
We show that a non-zero Ue3 close to the CHOOZ bound ($Sin^2 2 θ_{13} \simeq 0.16$ 90% CL) can change the geo-neutrino flux by 12%. Geo-neutrino detection in Kamland with a exposure of $3 \times 10^{32} proton-years$ is sensitive to $Sin^2 2 θ_{13}$ to the level of $0.2 (1 σ)$. For the same exposure a detector close to Himalayas can probe $Sin^2 2 θ_{13}$ do
Bodo Geyer, Oliver Witzel
Two- and three-particle distribution amplitudes of heavy pseudoscalar mesons of well-defined geometric twist are introduced. They are obtained from appropriately parametrized vacuum-to-meson matrix elements by applying those twist projectors which determine the enclosed light-cone operators of definite geometric twist and, in addition, observing the heavy qu
Samir Aknine, Onn Shehory
Solutions to the coalition formation problem commonly assume agent rationality and, correspondingly, utility maximization. This in turn may prevent agents from making compromises. As shown in recent studies, compromise may facilitate coalition formation and increase agent utilities. In this study we leverage on those new results. We devise a novel coalition
Fluctuations and the Effective Moduli of an Isotropic, Random Aggregate of Identical, Frictionless Spheres
cond-mat.softJ. Jenkins, D. Johnson, L. La Ragione, H. Makse
We consider a random aggregate of identical frictionless elastic spheres that has first been subjected to an isotropic compression and then sheared. We assume that the average strain provides a good description of how stress is built up in the initial isotropic compression. However, when calculating the increment in the displacement between a typical pair of
H. Johannesson, N. Andrei, C. J. Bolech
The two-channel Anderson impurity model serves as a prototype for describing heavy-fermion materials with a possible mixed-valent regime with both quadrupolar and magnetic character. We report on the low-energy physics of the model, using a conformal field theory approach with exact Bethe Ansatz results as input.
Approaching Unit Visibility for Control of a Superconducting Qubit with Dispersive Readout
cond-mat.mes-hallA. Wallraff, D. I. Schuster, A. Blais, L. Frunzio
In a Rabi oscillation experiment with a superconducting qubit we show that a visibility in the qubit excited state population of more than 90 % can be attained. We perform a dispersive measurement of the qubit state by coupling the qubit non-resonantly to a transmission line resonator and probing the resonator transmission spectrum. The measurement process i
Z. Farkas, S. R. Dahmen, D. E. Wolf
A simple model for solid friction is analyzed. It is based on tangential springs representing interlocked asperities of the surfaces in contact. Each spring is given a maximal strain according to a probability distribution. At their maximal strain the springs break irreversibly. Initially all springs are assumed to have zero strain, because at static contact
M. Zareyan, W. Belzig
We propose a three-terminal spin-valve setup, to determine experimentally the spin-dependent shot noise, which carries information on the spin-relaxation processes. Based on a spin-dependent Boltzmann-Langevin approach, we show that the spin Fano factor, defined as the spin shot noise to the mean charge current, strongly depends on the spin-flip scattering r
C. J. Bolech, T. Giamarchi
We revisit the problem of point-contact tunnel junctions involving one-dimensional superconductors and present a simple scheme for computing the full current-voltage characteristics within the framework of the non-equilibrium Keldysh Green function formalism. We address the effects of different pairing symmetries combined with magnetic fields and finite temp
F. Radu, V. Leiner, K. Westerholt, H. Zabel
Magnetic domain walls in thin films can be well analyzed using polarized neutron reflectometry. Well defined streaks in the off-specular spin-flip scattering maps are explained by neutron refraction at perpendicular Néel walls. The position of the streaks depends only on the magnetic induction within the domains, whereas the intensity of the off-specular mag
N. Bastian, M. Hempel, M. Kissler-Patig, N. Homeier
We present a photometric analysis of the rich star cluster population in the tidal tails of NGC 6872. We find star clusters with ages between 1 - 100 Myr distributed in the tidal tails, while the tails themselves have an age of less than 150 Myr. Most of the young massive ($10^{4} \le M/M_{\odot} \le 10^{7}$) clusters are found in the outer regions of the ga
P. Levai, G. Fai, G. Papp
The structure of hadron-hadron correlations is investigated in proton-proton collisions.We focus on the transmission of the initial transverse momenta of partons (``intrinsic $k_T$'') to the hadron-hadron correlations. Values of the intrinsic transverse momentum obtained from experimental correlations are compared to the results of a model with parti
Jerzy Matyjasek, O. B. Zaslavskii
We examine backreaction of quantum massive fields on multiply-degenerate (ultraextremal) horizons. It is shown that, under influence of the quantum backreaction, the horizon of such a kind moves to a new position, near which the metric does not change its asymptotics, so the ultraextremal black holes and cosmological spacetimes do exist as self-consistent so
Dave Lommen, Steve van Straaten, Michiel van der Klis, Brechtje Anthonisse
We analyse ~ 360 ks of archival data from the Rossi X-Ray Timing Explorer (RXTE) of the 21 hr orbital period dipping low-mass X-ray binary 4U 1624-49. We find that outside the dips the tracks in the colour-colour and hardness-intensity diagrams (CDs and HIDs) are reminiscent of those of atoll sources in the middle and upper parts of the banana branch. The tr
M. J. Biercuk, S. Garaj, N. Mason, J. M. Chow
We report the realization of nanotube-based quantum dot structures that use local electrostatic gating to produce individually controllable dots in series along a nanotube. Electrostatic top-gates produce depletion regions in the underlying tube; a pair of such depletion regions defines a quantum dot. Transparencies of tunnel barriers as well as the electros
Sudhir Raniwala, Marek Idzik, Rashmi Raniwala, Yogendra P. Viyogi
The coefficients that describe the anisotropy in the azimuthal distribution of particles are lower when the particles are recorded in a detector with finite granularity and measures only hits. This arises due to loss of information because of multiple hits in any channel. The magnitude of this loss of signal depends both on the occupancy and on the value of
Xiao-Gang He, Xue-Qian Li, Xiang Liu, Xiao-Qian Zeng
There are experimental evidences for the existence of narrow states $Θ^+$ and $Θ_c$ with the same quantum numbers of $uudd\bar s$ and $uudd\bar c$ pentaquarks and also $NK^{(*)}$ and $ND^{(*)}$ molecular states. Their masses deviate from many theoretical estimates of the pure pentaquark and molecular states. In this work we study the possibility that the obs
First Evidence for $B_s^0 \to ϕϕ$ Decay and Measurements of Branching Ratio and $A_{CP}$ for $B^+ \to ϕK^+$
hep-exCDF Collaboration, D. Acosta
We present the first evidence of charmless decays of the $B_s^0$ meson, the decay \phiphi, and a measurement of the Branching Ratio $\BR(\phiphi)$ using $180 {\rm pb}^{-1}$ of data collected by the \cdfii experiment at the Fermilab Tevatron collider. In addition, the BR and direct CP asymmetry for the \phik\ decay are measured. We obtain: $\BR (\phiphi) = (1
Arkady L. Kholodenko
A d-dimensional rational polytope P is a polytope whose vertices are located at the nodes of d-dimensional Z-lattice. Consider a number of points inside the inflated polytope (with coefficient of inflation k, k=1,2, 3...). The Ehrhart polynomial of P counts the number of such lattice points (nodes) inside the inflated P and (may be) at its faces (including v
Undoing static correlation: Long-range charge transfer in time-dependent density functional theory
physics.chem-phNeepa T. Maitra
Long-range charge transfer excited states are notoriously badly underestimated in time-dependent density functional theory (TDDFT). We resolve how {\it exact} TDDFT captures charge transfer between open-shell species: in particular the role of the step in the ground-state potential, and the severe frequency-dependence of the exchange-correlation kernel. An e
Victor P. Ruban
A new description for highly nonlinear potential water waves is suggested, where weak 3D effects are included as small corrections to exact 2D equations written in conformal variables. Contrary to the traditional approach, a small parameter in this theory is not the surface slope, but it is the ratio of a typical wave length to a large transversal scale alon
P. F. Weck, N. Balakrishnan
The H+LiF(X 1Sigma+,v=0-2,j=0)-->HF(X 1Sigma+,v',j')+Li(2S) bimolecular process is investigated by means of quantum scattering calculations on the chemically accurate X 2A' LiHF potential energy surface of Aguado et al. [J. Chem. Phys. 119, 10088 (2003)]. Calculations have been performed for zero total angular momentum for translational energies
Jorge G. Hirsch, Alejandro Frank, Jose Barea, Piet Van Isacker
Differences between measured nuclear masses and those calculated using the Finite Range Droplet Model are analyzed. It is shown that they have a well defined, clearly correlated oscillatory component as a function of the proton and neutron numbers. At the same time, they exhibit in their power spectrum the presence of chaos. Comparison with other mass calcul
M. Bruschi
Two simple Cellular Automata, which mimic the Collatz-Ulam iterated map (3x+1 map), are introduced. These Cellular Automata allow to test efficiently the Collatz conjecture for very large numbers.
A. M Perelomov
The goal of this note is to give the explicit solution of Euler-Frahm equations for the Manakov four-dimensional case by elementary means. For this, we use some results from the original papers by Schottky [Sch 1891], Koetter [Koe 1892], Weber [We 1878], and Caspary [Ca 1893]. We hope that such approach will be useful for the solution of the problem of $n$-d
Swiatoslaw R. Gal
We discuss one construction of nonstandard subgroups in the category of Coxeter groups. Two formulae for the growth series of such a subgroups are given. As an application we construct a flag simple convex polytope, whose f-polynomial has non-real roots.