October 2004 arXiv papers
Showing 1–100 of 4,138 papers
A. K. Kwasniewski
Umbral extensions of the stirling numbers of the second kind are considered and the resulting dobinski-like various formulas including new ones are presented. These extensions naturally encompass the two well known q-extensions. The further consecutive umbral extensions q-stirling numbers are therefore realized here in a two-fold way. The fact that the umbra
S. W. Ham, S. K. OH, D. Son
By assuming the existence of the sequential fourth generation to the minimal supersymmetric standard model (MSSM), we study the possibility of a strongly first-order electroweak phase transition. We find that there is a parameter region of the MSSM where the electroweak phase transition is strongly first order. In that parameter region, the mass of the light
Jonathan L. Rosner
The importance of measuring the non-$D \bar D$ decays of the $ψ'' = ψ(3770)$ resonance is discussed. These decays can shed light on a possible discrepancy between the total and $D \bar D$ cross sections at the $ψ''$, and on a proposed mechanism for enhancement of penguin amplitudes in $B$ meson decays through charm--anticharm annihilation. Me
Peter Kuchment
The paper deals with some spectral properties of (mostly infinite) quantum and combinatorial graphs. Quantum graphs have been intensively studied lately due to their numerous applications to mesoscopic physics, nanotechnology, optics, and other areas. A Schnol type theorem is proven that allows one to detect that a point belongs to the spectrum when a genera
Sergei Bashinsky
When the perturbations forming the acoustic peaks of the cosmic microwave background (CMB) reentered the horizon and interacted gravitationally with all the matter, neutrinos presumably comprised 41% of the universe energy. CMB experiments have reached a capacity to probe this background of relic neutrinos. I review the neutrino impact on the CMB at the onse
Nathanaël Berestycki
Turn the set of permutations of $n$ objects into a graph $G_n$ by connecting two permutations that differ by one transposition, and let $σ_t$ be the simple random walk on this graph. In a previous paper, Berestycki and Durrett [In Discrete Random Walks (2005) 17--26] showed that the limiting behavior of the distance from the identity at time $cn/2$ has a pha
Hoi-Kwong Lo, Xiongfeng Ma, Kai Chen
There has been much interest in quantum key distribution. Experimentally, quantum key distribution over 150 km of commercial Telecom fibers has been successfully performed. The crucial issue in quantum key distribution is its security. Unfortunately, all recent experiments are, in principle, insecure due to real-life imperfections. Here, we propose a method
Laura Lising, Andrew Elby
We discuss a case study of the influence of epistemology on learning for a student in an introductory college physics course. An analysis of videotaped class work, written work, and interviews indicates that many of the student's difficulties were epistemological in nature. Our primary goal is to show instructors and curriculum developers that a student&
G. N. Ord, J. A. Gualtieri, R. B. Mann
In the path integral formulation of quantum mechanics, the phase factor Exp[iS(x[t])] is associated with every path x[t]. Summing this factor over all paths yields Feynman's propagator as a sum-over-paths. In the original formulation, the complex phase was a mathematical device invoked to extract wave behaviour in a particle framework. In this paper we s
The controlled indirect coupling between spatially-separated qubits in antiferromagnet-based NMR quantum registers
quant-phA. A. Kokin
It is considered the indirect inter-qubit coupling in 1D chain of atoms with nuclear spins 1/2, which plays role of qubits in the quantum register. This chain of the atoms is placed by regular way in easy-axis 3D antiferromagnetic thin plate substrate, which is cleaned from the other nuclear spin containing isotopes. It is shown that the range of indirect in
G. Vernizzi, H. Orland, A. Zee
We enumerate the number of RNA contact structures according to their genus, i.e. the topological character of their pseudoknots. By using a recently proposed matrix model formulation for the RNA folding problem, we obtain exact results for the simple case of an RNA molecule with an infinitely flexible backbone, in which any arbitrary pair of bases is allowed
Zhen Ye
This paper considers acoustic scattering by and propagation through line and plane arrays of air-bubbles in liquid media. The self-consistent method is used to derive the effective scattering function of a single bubble embedded in the arrays, incorporating all multiple scattering processes. For the line case, an exact result is derived. In the plane array s
V. V. Begun, M. I. Gorenstein, O. S. Zozulya
The particle number and energy fluctuations in the system of charged particles are studied in the canonical ensemble for non-zero net values of the conserved charge. In the thermodynamic limit the fluctuations in the canonical ensemble are different from the fluctuations in the grand canonical one. The system with several species of particles is considered.
Neutrino accompanied beta^-beta^-, beta^+beta^+, beta^+/EC and EC/EC processes within single state dominance hypothesis
nucl-thP. Domin, S. Kovalenko, F. Simkovic, S. V. Semenov
The systematic study of (anti-)neutrino accompanied beta^-beta^-, beta^+beta^+ decays and beta^+/EC, EC/EC electron captures is performed under the assumption of single intermediate nuclear state dominance. The corresponding half-lives are evaluated both for transitions to the ground state as well as to the 0^+ and 2^+ excited states of final nucleus. It is
Kaihua Cai
We prove $t^{- \frac 14}-$decay for the solutions of the 1-dim Schrodinger equation with a one-gap periodic potential as $t \to +\infty $. Generically, one has $t^{- \frac 13}$-decay and this decay is optimal. Our approach is to analyze the stationary phase in the Schrödinger evolution as an integral operator.
Ravi Montenegro
We consider the problem of lower bounding a generalized Minkowski measure of subsets of a convex body with a log-concave probability measure, conditioned on the set size. A bound is given in terms of diameter and set size, which is sharp for all set sizes, dimensions, and norms. In the case of uniform density a stronger theorem is shown which is also sharp.
Sungbok Hong, Darryl McCullough, J. Hyam Rubinstein
The original Smale Conjecture asserted that the inclusion of the group O(4) of isometries of the round 3-sphere S into the full diffeomorphism group Diff(S) is a homotopy equivalence. The (Generalized) Smale Conjecture asserts that the inclusion of Isom(M) into Diff(M) is a homotopy equivalence whenever M is an elliptic 3-manifold, that is, a closed Riemanni
J. Fleckinger, E. M. Harrell, F. de Thélin
It is shown that the fundamental eigenvalue ratio λ_2 / λ_1 of the p-Laplacian is bounded by a quantity depending only on the dimension N and p.
Knut Smoczyk, Guofang Wang, Y. L. Xin
We show that flatness of the normal bundle is preserved under the mean curvature flow in the Euclidean space and use this to generalize a classical result for hypersurfaces due to Ecker-Huisken in the case of submanifolds with arbitrary codimension.
Eran Nevo
Gluck (1975) has proven that triangulated 2-spheres are generically 3-rigid. Equivalently, planar graphs are generically 3-stress free. We show that linklessly embeddable graphs are generically 4-stress free. Both of these results are corollaries of the following theorem: every K_{r+2}-minor free graph is generically r-stress free for 0<r<5. (This assertion
On the reconstruction of the drift of a diffusion from transition probabilities which are partially observed in space
math.PRSergio Albeverio, Carlo Marinelli
The problem of reconstructing the drift of a diffusion in $\erre^d$, $d\geq 2$, from the transition probability density observed outside a domain is considered. The solution of this problem also solves a new inverse problem for a class of parabolic partial differential equations. This work considerably extends \cite{jsp} in terms of generality, both concerni
Ewa Krot
The explicite formulas for möbiusien function and some other important elements of the incidence algebra are delivered. For that to do one uses kwaśniewski's construction of his fibonacci cobweb poset in the plane grid coordinate system.
Alfred J. van der Poorten
We generalise remarks of Euler and of Perron by explaining how to detail all quadratic irrational integers for which the symmetric part of the period of their continued fraction expansion commences with prescribed partial quotients. The function field case is particularly striking.
Kalle Karu
The number of flags in a complete fan, or more generally in an Eulerian poset, is encoded in the cd-index. We prove non-negativity of the cd-index for complete fans, regular CW-spheres and Gorenstein* posets.
Dave Auckly, Martin Speight
The fundamental group and rational cohomology of the configuration spaces of the Skyrme and Faddeev-Hopf models are computed. Physical space is taken to be a compact oriented 3-manifold, either with or without a marked point representing an end at infinity. For the Skyrme model, the codomain is any Lie group, while for the Faddeev-Hopf model it is $S^2$. It
Non-critical, near extremal AdS_6 background as a holographic laboratory of four dimensional YM theory
hep-thS. Kuperstein, J. Sonnenschein
We study certain properties of the low energy regime of a theory which resembles four dimensional YM theory in the framework of a non-critical holographic gravity dual. We use for the latter the near extremal $AdS_6$ non-critical SUGRA. We extract the glueball spectra that associates with the fluctuations of the dilaton, one form and the graviton and compare
Theodore N. Tomaras
A rich variety of brane cosmologies is obtained once one allows for energy exchange between the brane and the bulk, depending on the precise form of energy transfer, on the equation of state of matter on the brane and on the spatial topology. This is demonstrated in the context of a non-factorizable background geometry with zero effective cosmological consta
H. Yuksel
Emergence of neutrino physics is fueled by the recent growth in quality and quantity of experimental data, yet, there are still open questions. How much can the determination of mixing parameters be improved? Can we improve bounds on theta_13 before experiments designed specifically for this parameter start? How well can we determine or limit sterile fractio
P. Ramond
The prediction of small neutrino masses through the Seesaw Mechanism and their subsequent measurement suggests that the natural cut-off of the Standard Model is very high indeed. The recent neutrino data must be interpreted as a reflection of physics at very high energy. We examine their implications in terms of ideas of Grand Unification and Supersymmetry,
P. Ramond
The Seesaw mechanism predicted tiny neutrino masses by postulating a new large scale in particle physics, using new theoretical ideas prompted by the Standard Model. It adds credence to a theoretical vista that is a quarter century old, and fits with the most endearing speculations of ultimate unification. By relating the measurement of static neutrino prope
M. Beneke, N. Kauer, A. Signer, G. Zanderighi
We illustrate the use of effective theory techniques to describe processes involving unstable particles close to resonance. First, we present the main ideas in the context of a scalar resonance in an Abelian gauge-Yukawa model. We then outline the necessary modifications to describe W-pair production close to threshold in electron-positron collisions.
Piotr T. Chrusciel
We review selected recent results concerning the global structure of solutions of the vacuum Einstein equations. The topics covered include quasi-local mass, strong cosmic censorship, non-linear stability, new constructions of solutions of the constraint equations, improved understanding of asymptotic properties of the solutions, existence of solutions with
Igor V. Roshchin, O. Petracic, R. Morales, Zhi-Pan Li
When a ferromagnet is in proximity with an antiferromagnet, lateral length scales such as the respective magnetic domain sizes drastically affect the exchange bias. Bilayers of FeF2 and either Ni, Co or Fe are studied using SQUID and spatially resolved MOKE. When the antiferromagnetic domains are larger than or comparable to the ferromagnetic domains, a loca
Superconductivity and Density Wave in the Quasi-One-Dimensional Systems: Renormalization Group Study
cond-mat.str-elY. Fuseya, Y. Suzumura
The anisotropic superconductivity and the density wave have been investigated by applying the Kadanoff-Wilson renormalization group technique to the quasi-one-dimensional system with finite-range interactions. It is found that a temperature (T) dependence of response functions is proportional to exp(1/T) in a wide region of temperature even within the one-lo
Jun-ichi Nakashima
The author reports a result of an interferometric observation of the semiragular pulsating star with an unusual narrow molecular line profile, X Her, in the CO J=1-0 line with the Berkeley-Illinois-Maryland array. In the CO spectrum, a double-component profile (including narrow and broad components) is seen as reported by previous observations. The narrow co
John M. Carpenter, Sebastian Wolf, Katharina Schreyer, Ralf Launhardt
We present submillimeter (CSO 350um) and millimeter (SEST 1.2 mm, OVRO 3 mm) photometry for 125 solar-type stars from the FEPS Spitzer Legacy program that have masses between ~0.5 and 2.0 Msun and ages from 3 Myr to 3 Gyr. Continuum emission was detected toward four stars with a signal to noise ratio >= 3$: the classical T Tauri stars RX J1842.9-3532, RX J18
D. J. Christian, D. L. Pollacco, W. I. Clarkson, A. Collier Cameron
We present the current status of the SuperWASP project, a Wide Angle Search for Planets. SuperWASP consists of up to 8 individual cameras using ultra-wide field lenses backed by high-quality passively cooled CCDs. Each camera covers 7.8 x 7.8 sq degrees of sky, for nearly 500 sq degrees of sky coverage. SuperWASP I, located in LaPalma, is currently operation
R. X. Xu, A. Z. Zhou
A quake model of bare strange stars for normal pulsar glitches is summarized. Three mechanisms being responsible for developing elastic stress energy are presented. It is suggested that other kinds of glitches (e.g, the frequency glitch in KS 1947+300 and in AXP/SGRs) could represent the bulk-strain-induced quakes. The apparent field increase of normal pulsa
P. Lesaffre, Ph. Podsiadlowski, C. A. Tout
One possible fate of an accreting white dwarf is explosion in a type Ia supernova. However, the route to the thermonuclear runaway has always been uncertain owing to the lack of a convective model consistent with the Urca process. We derive a formalism for convective motions involving two radial flows. This formalism provides a framework for convective model
P. Lesaffre, Ph. Podsiadlowski, C. A. Tout
We derive a new formalism for convective motions involving two radial flows. This formalism provides a framework for convective models that guarantees consistency for the chemistry and the energy budget in the flows, allows time-dependence and accounts for the interaction of the convective motions with the global contraction or expansion of the star. In the
Jörn Dunkel, Peter Hänggi
We construct a theory for the 1+1-dimensional Brownian motion in a viscous medium, which is (i) consistent with Einstein's theory of special relativity, and (ii) reduces to the standard Brownian motion in the Newtonian limit case. In the first part of this work the classical Langevin equations of motion, governing the nonrelativistic dynamics of a free B
Horacio E. Camblong, Carlos R. Ordonez
The thermodynamics of black holes is shown to be directly induced by their near-horizon conformal invariance. This behavior is exhibited using a scalar field as a probe of the black hole gravitational background, for a general class of metrics in D spacetime dimensions (with $D \geq 4$). The ensuing analysis is based on conformal quantum mechanics, within a
J. E. Daily, R. Gommers, E. A. Cummings, D. S. Durfee
We report an optical dipole trap for calcium. The trap is created by focusing a 488 nm argon-ion laser beam into a calcium magneto-optical trap. The argon-ion laser photo-ionizes atoms in the trap because of a near-resonance with the 4s4f 1F3 level. By measuring the dipole trap decay rate as a function of argon-ion laser intensity, we determine the 1F3 photo
Steven D. Bass
This article reviews our present understanding of the QCD spin structure of the proton. We first outline the proton spin puzzle and its possible resolution in QCD. We then review the present and next generation of experiments to resolve the proton's spin-flavour structure, explaining the theoretical issues involved, the present status of experimental inv
Alvaro Gonzalez, Javier B. Gomez, Amalio F. Pacheco
The occurrence of the September 28, 2004 Mw=6.0 mainshock at Parkfield, California, has significantly increased the mean and aperiodicity of the series of time intervals between mainshocks in this segment of the San Andreas fault. We use five different statistical distributions as renewal models to fit this new series and to estimate the time-dependent proba
Tamas Varga
Permutation actions of simple currents on the primaries of a Rational Conformal Field Theory are considered in the framework of admissible weighted permutation actions. The solution of admissibility conditions is presented for cyclic quadratic groups: an irreducible WPA corresponds to each subgroup of the quadratic group. As a consequence, the primaries of a
Yaron Bromberg, M. C. Cross, Ron Lifshitz
We study the response of a large array of coupled nonlinear oscillators to parametric excitation, motivated by the growing interest in the nonlinear dynamics of microelectromechanical and nanoelectromechanical systems (MEMS and NEMS). Using a multiscale analysis, we derive an amplitude equation that captures the slow dynamics of the coupled oscillators just
Resolving the order parameter of High-T$_{c}$ Superconductors through quantum pumping spectroscopy
cond-mat.supr-conColin Benjamin
The order parameter of High-T$_{c}$ superconductors through a series of experiments has been quite conclusively demonstrated to not be of the normal $s-wave$ type. It is either a pure $d_{x^{2}-y^{2}}$-wave type or a mixture of a $d_{x^{2}-y^{2}}-wave$ with a small imaginary $s-wave$ or $d_{xy}-wave$ component. In this work a distinction is brought out among
Xin Liu, Xiong-Jun Liu, Mo-Lin Ge
The dynamics of the domain wall (DW) in a biaxial ferromagnet interacting with a spin-polarized current are described by sine-gordon (SG) equation coupled with Gilbert damping term in this paper. Within our frame-work of this model, we obtain a threshold of the current in the motion of a single DW with the perturbation theory on kink soliton solution to the
The simplest quantum model supporting the Kibble-Zurek mechanism of topological defect production: Landau-Zener transitions from a new perspective
cond-mat.otherBogdan Damski
It is shown that dynamics of the Landau-Zener model can be accurately described in terms of the Kibble-Zurek theory of the topological defect production in nonequilibrium phase transitions. The simplest quantum model exhibiting the Kibble-Zurek mechanism is presented. A new intuitive description of Landau-Zener dynamics is found.
W. Bietenholz, S. Capitani, T. Chiarappa, N. Christian
We compare the behavior of overlap fermions, which are chirally invariant, and of Wilson twisted mass fermions at full twist in the approach to the chiral limit. Our quenched simulations reveal that with both formulations of lattice fermions pion masses of O(250 MeV) can be reached in practical applications. Our comparison is done at a fixed value of the lat
Jaemo Park, Takao Suyama
We investigate a deformed matrix model of type 0A theory related to supersymmetric Witten's black hole in two-dimensions, generalization of bosonic model suggested by Kazakov et. al. We find a free field realization of the partition function of the matrix model, which includes Ramond-Ramond perturbations in the type 0A theory. In a simple case, the parti
Yu Tian, Han-Ying Guo, Chao-Guang Huang, Zhan Xu
We focus on the dynamical aspects of Newton-Hooke space-time ${\cal NH}_+$ mainly from the viewpoint of geometric contraction of the de Sitter spacetime. We first discuss the Newton-Hooke classical mechanics, especially the continuous medium mechanics, in this framework. Then, we establish a consistent theory of gravity on the Newton-Hooke space-time as a ki
Pietro Menotti, Gabriele Vajente
We solve the Riemann-Hilbert problem on the sphere topology for three singularities of finite strength and a fourth one infinitesimal, by determining perturbatively the Poincare' accessory parameters. In this way we compute the semiclassical four point vertex function with three finite charges and a fourth infinitesimal. Some of the results are extended
P. Sancho
Multimode two-particle systems show interference effects in one-particle detections when both particles have common modes. We explore the possibility of extending the usual concepts of distinguishability and visibility to these types of systems. Distinguishability will refer now to the balance between common and different modes of a two-particle system, inst
Kai Wang, Nilanjana Banerjee, Adam Margolin, Ilya Nemenman
Cellular phenotypes are determined by the dynamical activity of networks of co-regulated genes. Elucidating such networks is crucial for the understanding of normal cell physiology as well as for the dissection of complex pathologic phenotypes. Existing methods for such "reverse engineering" of genetic networks from microarray expression data have be
David H. Douglass, B. David Clader, Robert S. Knox
This paper is a continuation of a study by Douglass and Clader. We extend the analysis through December 2003 using the latest updates of the observational temperature and solar irradiance data sets in addition to a new volcano proxy data set. We have re-determined the solar effect on the temperature from satellite measurements of the solar irradiance and the
F. Bentosela, P. Duclos, G. Nenciu, V. Moldoveanu
We study the dynamics of a 1D Bloch electron subjected to a constant electric field. The periodic potential is supposed to be less singular than the $δ$-like potential (Dirac comb). We give a rigorous proof of Ao's result \cite{Ao} that for a large class of initial conditions (high momentum regime) there is no localization in momentum space. The proof is
Stephen Semmes
These notes, associated with a topics course, are concerned with Hausdorff measures and Lipschitz functions on metric spaces.
Masoud Khalkhali, Bahram Rangipour
We construct cup products of two different kinds for Hopf-cyclic cohomology. When the Hopf algebra reduces to the ground field our first cup product reduces to Connes' cup product in ordinary cyclic cohomology. The second cup product generalizes Connes-Moscovici's characteristic map for actions of Hopf algebras on algebras.
Tom Braden, Valery A. Lunts
For a pair of affine toric varieties X and Y defined by dual cones, we define an equivalence between two triangulated categories. The first is a mixed version of the equivariant derived category of X and the second is a mixed version of the derived category of sheaves on Y which are locally constant with unipotent monodromy on each orbit. This equivalence sa
Takeo Nishinou
The purpose of this paper is to exhibit a natural construction between complex geometry and symplectic geometry following the idea of mirror symmetry. Suppose we are given a family of pairs of 2-dimensional Kähler tori and stable holomorphic vector bundles on them $(\hat M_{\ep}, E_{\ep})$, \ep \in (0, 1]$, and each has structure of a Lagrangian torus fibrat
G. Giachetta, L. Mangiarotti, G. Sardanashvily
Covariant (polysymplectic) Hamiltonian field theory is formulated as a particular Lagrangian theory on a polysymplectic phase space that enables one to quantize it in the framework of familiar quantum field theory.
G. Pancheri, Y. Srivastava, N. Staffolani
A sum rule is derived for elastic scattering of hadrons at high energies which is in good agreement with experimental data on $p\bar{p}$ available upto the maximum energy $\sqrt{s} = 2 TeV$. Physically, our sum rule reflects the way unitarity correlates and limits how large the elastic amplitude can be as a function of energy to how fast it decreases as a fu
G. Pancheri, R. Godbole, A. Grau, Y. N. Srivastava
The physics underlying the fall and eventual rise in various total cross-sections at high energies has been investigated over a decade using a model based on the Bloch-Nordsieck resummation in QCD. Here a brief review of our latest results is presented and comparison made with experimental data on $pp$, $γproton$ and $γγ$ total cross-sections.
Palatini formulation of the $R^{-1}$modified gravity with an additionally squared scalar curvature term
gr-qcXin He Meng, Peng Wang
In this paper by deriving the Modified Friedmann equation in the Palatini formulation of $R^2$ gravity, first we discuss the problem of whether in Palatini formulation an additional $R^2$ term in Einstein's General Relativity action can drive an inflation. We show that the Palatini formulation of $R^2$ gravity cannot lead to the gravity-driven inflation
J. A. Belinchón
It is investigated the behaviour of the ``constants'' $G,$ $c$ and $Λ$ in the framework of a perfect fluid LRS Bianchi I cosmological model. It has been taken into account the effects of a $c-$variable into the curvature tensor. Two exact cosmological solutions are investigated, arriving to the conclusion that if $q<0$ (deceleration parameter) then $
L. A. Openov, A. V. Tsukanov
Quantum operations with a charge solid-state qubit whose logical states are formed by two spatially separated localized states of an electron in the double-dot structure are studied theoretically. We show that it is possible to perform various one-qubit rotations making use of the microwave pulses tuned to the resonances between the localized states and the
Evolution of Electronic and Vibrational Polarity of NaF Nanocrystals from Diatomic to Bulk: A Density Functional Study
cond-mat.otherChristian Schmidt, Philip B. Allen, Tunna Baruah, Mark Pederson
Density functional theory (DFT) is used to study vibrations, electrical dipole moments, and polarizabilities of NaF clusters. Because of prior experimental and theoretical studies, this is a good model system for tracking the evolution of the properties from diatomic molecule to bulk crystal. The ratio of vibrational to electronic contributions to the polari
L. N. Shehata, H. M. Taha
The modified Ginzburg-Landau equations are used to study some fundamental problems for the high temperature superconductors. The derivations of these fundamental equations are summarized and the layered features of the sample were taken into consideration and the relation between the coherence length and the separation distance of the layers. The domain wall
Zhen Ye
Here I present an overview of recent studies of the phenomenon of negative refraction and left-handed materials. I will discuss some basic questions pertinent to the problem. It is pointed out that the current claims of negative refraction and left handed materials are not conclusive. To support our consideration, I will start with the fundamental physics.
Jian-Ming Tang, Michael E. Flatte'
We study sharp low-energy resonance peaks in the local density of states (LDOS) induced by Zn impurities or possible Cu vacancies in superconducting Bi_2Sr_2CaCu_2O_{8+delta}. The measured structure of these near-zero-bias resonances is quantitatively reproduced by an extended impurity potential without invoking internal impurity states or sophisticated tunn
Chao-Hsien Kuo, Zhen Ye
In a recent communication, Parimi et al. (Nature 426, 404 (2003)) reported the experimental results on imaging by a flat lens made of photonic crystals. They attributed the observed focusing to the negative refraction expected for the Left-Handed-Materials (LHMs). Here we demonstrate that the experimental observation is irrelevant to the negative refraction
Bruce W. Carney, Jae-Woo Lee, Benjamin Dodson
We present deep JHK photometry of the old and metal-rich open cluster NGC 6791. The photometry reaches below the main sequence turn-off to K = 16.5 mag. We combine our photometry with that from Stetson, Bruntt, & Grundahl (2003) to provide color-magnitude diagrams showing K vs. J-K, K vs. V-K, and V vs. V-K. We study the slope of the red giant branch in the
Probing the wind-wind collision in Gamma Velorum with high-resolution Chandra X-ray spectroscopy: evidence for sudden radiative braking and non-equilibrium ionization
astro-phD. B. Henley, I. R. Stevens, J. M. Pittard
We present a new analysis of an archived Chandra HETGS X-ray spectrum of the WR+O colliding wind binary Gamma Velorum. The spectrum is dominated by emission lines from astrophysically abundant elements: Ne, Mg, Si, S and Fe. From a combination of broad-band spectral analysis and an analysis of line flux ratios we infer a wide range of temperatures in the X-r
L. C. Popovic
In order to investigate the connection between the X-ray, UV and optical spectral line regions, we selected a sample of AGN which have the strong Fe K-alpha line and analyze the UV and optical spectral lines. Here we present an example of AGN NGC 3516. In this object it seems that geometries of all three emitting regions are similar, i.e. the broad line shap
M. J. Seaton
All monochromatic opacity data from the Opacity Project (OP), together with all codes required for the calculation of mean opacities and radiative accelerations for any required chemical mixture, temperature and mass-density, are being put on a 700 Mb CD which will be made generally available. The present paper gives a concise summary of the contents of the
T. von Hippel, D. E. Winget, W. H. Jefferys, J. G. Scott
We present an update of our on-going effort to improve the precision of white dwarf cosmochronology via careful analyses of white dwarf photometry in open clusters. To improve the precision of white dwarf and main sequence age analysis, we are developing a new interpretative scheme using a Bayesian statistical approach that matches observations to simulated
T. von Hippel, M. Kilic, J. Munn, H. Harris
We describe a new survey for cool white dwarfs that supplements Sloan Digital Sky Survey photometry with USNO proper motions and follow-up spectroscopy. To date we have discovered and spectroscopically confirmed 80 new moderate temperature and cool white dwarfs. We have also found a handful of high-velocity white dwarfs and we expect a sizable fraction of th
Hsiao-Wen Chen, Robert C. Kennicutt, Michael Rauch
We present a spectroscopic study of six damped Lya absorption (DLA) systems at z<0.65, based on moderate-to-high resolution spectra of the galaxies responsible for the absorbers. Combining known metallicity measurements of the absorbers with known optical properties of the absorbing galaxies, we confirm that the low metal content of the DLA population can ar
L. H. Ford, R. P. Woodard
We express stress tensor correlators using the Schwinger-Keldysh formalism. The absence of off-diagonal counterterms in this formalism ensures that the +- and -+ correlators are free of primitive divergences. We use dimensional regularization in position space to explicitly check this at one loop order for a massless scalar on a flat space background. We use
Cosmogenic 11C production and sensitivity of organic scintillator detectors to pep and CNO neutrinos
hep-phC. Galbiati, A. Pocar, D. Franco, A. Ianni
Several possible background sources determine the detectability of pep and CNO solar neutrinos in organic liquid scintillator detectors. Among such sources, the cosmogenic 11C nuclide plays a central role. 11C is produced underground in reactions induced by the residual cosmic muon flux. Experimental data available for the effective cross section for 11C by
M. Ablikim
A partial wave analysis is presented of $J/ψ\to ϕπ^+π^-$ and $ϕK^+K^-$ from a sample of 58M $J/ψ$ events in the BES II detector. The $f_0(980)$ is observed clearly in both sets of data, and parameters of the Flatt\' e formula are determined accurately: $M = 965 \pm 8$ (stat) $\pm 6$ (syst) MeV/c$^2$, $g_1 = 165 \pm 10 \pm 15 $ MeV/c$^2$, $g_2/g_1 = 4.21
Steven J. Bidder, N. E. J. Bjerrum-Bohr, Lance J. Dixon, David C. Dunbar
Recently, it has been shown that the holomorphic anomaly of unitarity cuts can be used as a tool in determining the one-loop amplitudes in N=4 super Yang-Mills theory. It is interesting to examine whether this method can be applied to more general cases. We present results for a non-MHV N=1 supersymmetric one-loop amplitude. We show that the holomorphic anom
The Initial Configuration of Young Stellar Clusters: A K-band Number Counts Analysis of the Surface Density of Stars
astro-phR. A. Gutermuth, S. T. Megeath, J. L. Pipher, J. P. Williams
We present an analysis of K-band stellar distributions for the young stellar clusters GGD 12-15, IRAS 20050+2720, and NGC 7129. We find that the two deeply embedded clusters, GGD 12-15 and IRAS 20050+2720, are not azimuthally symmetric and show a high degree of structure which traces filamentary structure observed in 850 micron emission maps. In contrast, th
Marc-Thierry Jaekel, Serge Reynaud
We build up a new phenomenological framework associated with a minimal generalization of Einsteinian gravitation theory. When linearity, stationarity and isotropy are assumed, tests in the solar system are characterized by two potentials which generalize respectively the Newton potential and the parameter $γ$ of parametrized post-Newtonian formalism. The new
Toshihiko Ota, Joe Sato
We evaluate the size of a coupling for a lepton flavor violating interaction with neutrinos (nLFV) in the minimal supersymmetric standard model with right-handed neutrinos (MSSMRN). It is expected that the nLFV interactions are detected in a long baseline neutrino oscillation experiment. We here deal with $μ^{-} \to e^{-} \barν_{e} ν_τ$ in $ν_μ \to ν_τ$ chan
N. R. Badnell, M. A. Bautista, K. Butler, F. Delahaye
Using the code AUTOSTRUCTURE, extensive calculations of inner-shell atomic data have been made for the chemical elements He, C, N, O, Ne, Na, Mg, Al, Si, S, Ar, Ca, Cr, Mn, Fe and Ni. The results are used to obtain up-dated opacities from the Opacity Project, OP. A number of other improvements on earlier work have also been included. Rosseland-mean opacities
Probing the Light Speed Anisotropy with respect to the Cosmic Microwave Background Radiation Dipole
astro-phV. G. Gurzadyan, J. -P. Bocquet, A. Kashin, A. Margarian
We have studied the angular fluctuations in the speed of light with respect to the apex of the dipole of Cosmic Microwave Background (CMB) radiation using the experimental data obtained with GRAAL facility, located at the European Synchrotron Radiation Facility (ESRF) in Grenoble. The measurements were based on the stability of the Compton edge of laser phot
Igor Kriz, Hisham Sati
In the presence of background Neveu-Schwarz flux, the description of the Ramond-Ramond fields of type IIB string theory using twisted K-theory is not compatible with S-duality. We argue that other possible variants of twisted K-theory would still not resolve this issue. We propose instead a possible path to a solution using elliptic cohomology. We also discu
The Topological B-Model on Fattened Complex Manifolds and Subsectors of N=4 Self-Dual Yang-Mills Theory
hep-thChristian Saemann
In this paper, we propose so-called fattened complex manifolds as target spaces for the topological B-model. We naturally obtain these manifolds by restricting the structure sheaf of the N=4 supertwistor space, a process, which can be understood as a fermionic dimensional reduction. Using the twistorial description of these fattened complex manifolds, we con
A. Belhaj, L. B. Drissi, J. Rasmussen, E. H. Saidi
We study mirror symmetry of supermanifolds constructed as fermionic extensions of compact toric varieties. We mainly discuss the case where the linear sigma A-model contains as many fermionic fields as there are U(1) factors in the gauge group. In the mirror super-Landau-Ginzburg B-model, focus is on the bosonic structure obtained after integrating out all t
Non-Linear Deformations of Liquid-Liquid Interfaces Induced by Electromagnetic Radiation Pressure
physics.opticsAslak Hallanger, Iver Brevik, Skjalg Haaland, Roger Sollie
The idea of working with a near-critical phase-separated liquid mixture whereby the surface tension becomes weak, has recently made the field of laser manipulation of liquid interfaces a much more convenient tool in practice. The deformation of interfaces may become as large as several tenths of micrometers, even with the use of conventional laser power. Thi
Erich J. Mueller
We explore the theory of electrons confined by one dimensional power law potentials. We calculate the density profile in the high density electron gas, the low density Wigner crystal, and the intermediate regime. We extract the momentum space wavefunction of the electron at the Fermi surface, which can be measured in experiments on tunneling between parallel
Xiangdong Li C. M. Shakin
There is a good deal of current interest in the condensate A^2 which has been seen to play an important role in calculations which make use of the operator product expansion. That development has led to the publication of a large number of papers which discuss how that condensate could play a role in a gauge-invariant formulation. In the present work we cons
The Distribution of Pressures in a Supernova-Driven Interstellar Medium. I. Magnetized Medium
astro-phMordecai-Mark Mac Low, Dinshaw S. Balsara, Jongsoo Kim, Miguel A. Avillez
Observations have suggested substantial departures from pressure equilibrium in the interstellar medium (ISM) in the plane of the Galaxy, even on scales under 50 pc. Nevertheless, multi-phase models of the ISM assume at least locally isobaric gas. The pressure then determines the density reached by gas cooling to stable thermal equilibrium. We use numerical
E. W. Dvergsnes, P. Osland, A. A. Pankov, N. Paver
We present an analysis, based on the center-edge asymmetry, to distinguish effects of extra dimensions within the Arkani-Hamed-Dimopoulos-Dvali (ADD) and Randall-Sundrum (RS) scenarios from other new physics effects in lepton-pair production at the CERN Large Hadron Collider LHC. Spin-2 and spin-1 exchange can be distinguished up to an ADD cutoff scale, M_H,
Sean Cleary, Murray Elder, Jennifer Taback
We study languages of geodesics in lamplighter groups and Thompson's group F. We show that the lamplighter groups $L_n$ have infinitely many cone types, have no regular geodesic languages, and have 1-counter, context-free and counter geodesic languages with respect to certain generating sets. We show that the full language of geodesics with respect to on
J. A. Hillman, S. K. Roushon
We show that although closed $\widetilde{\Bbb{SL}}\times\Bbb{E}^n$-manifolds do not admit metrics of nonpositive sectional curvature, the arguments of Farrell and Jones can be extended to show that such manifolds are topologically rigid, if $n\geq2$.
R. Casalbuoni, R. Gatto, M. Mannarelli, G. Nardulli
We calculate the Meissner masses of gluons in neutral three-flavor color superconducting matter for finite strange quark mass. In the CFL phase the eissner masses are slowly varying function of the strange quark mass. For large strange quark mass, in the so called gCFL phase, the Meissner masses of gluons with colors $a=1,2,3$ and 8 become imaginary, indicat