May 2008 arXiv papers — page 6
Showing 501–600 of 4,900 papers
M. Gomes, T. Mariz, J. R. Nascimento, E. Passos
We investigate the occurrence of ambiguities for Lorentz-violating gravitational Chern-Simons term. It turns out that this term is accompanied by a coefficient depending on an undetermined parameter, due to an arbitrariness in the choice of the conserved current.
Xavier Rouby
The CMS/TOTEM and ATLAS collaborations carry out a program of forward physics with several near-beam detectors extending their coverage to high pseudorapidities. This instrumentation includes calorimeters (CASTOR and ZDC), tracking devices (TOTEM T1 and T2), proton taggers (Roman Pots and FP420), and instrumentation dedicated to luminosity monitoring and nor
Kazuhiro Nagata
Employing a novel type of non-commutative product in the Dirac-Kahler twisted superspace on a lattice, we formulate a field theoretically rigid framework of extended supersymmetry on a lattice. As a first example of this treatment, we calculate one-loop (in some cases any loops) quantum corrections for a twisted Wess-Zumino model with N \times N hermitian ma
From itinerant to local-moment antiferromagnetism in Kondo lattices: Adiabatic continuity vs. quantum phase transitions
cond-mat.str-elMatthias Vojta
Motivated by both experimental and theoretical activities, we discuss the fate of Kondo screening and possible quantum phase transitions in antiferromagnetically ordered phases of Kondo lattices. While transitions with topological changes of the Fermi surface may occur, we demonstrate that an entirely continuous evolution from itinerant to local-moment antif
The bright galaxy population of five medium redshift clusters. I. Color-Magnitude Relation, Blue Fractions and Visual Morphology
astro-phB. Ascaso, M. Moles, J. A. L. Aguerri, R. Sánchez-Janssen
Using data of five clusters of galaxies within the redshift range 0.15 $\leq$ z $\leq$ 0.25, imaged with the Nordic Optical Telescope (NOT) in the central $\approx$ 1 Mpc$^2$ in very good seeing conditions, we have performed an exhaustive inspection of their bright galaxy population. That range of redshift, where only a small amount of data with the required
Paul de Medeiros, José Figueroa-O'Farrill, Elena Méndez-Escobar
We classify Lie 3-algebras possessing an invariant lorentzian inner product. The indecomposable objects are in one-to-one correspondence with compact real forms of metric semisimple Lie algebras. We analyse the moduli space of classical vacua of the Bagger-Lambert theory corresponding to these Lie 3-algebras. We establish a one-to-one correspondence between
Monika Blanke, Andrzej J. Buras, Stefan Recksiegel, Cecilia Tarantino
The non-minimal flavour violating interactions of mirror quarks and new heavy gauge bosons in the Littlest Higgs model with T-parity (LHT) give rise to naturally large CP-violating effects in the B_s system. In view of a large new CP phase in B_s - anti-B_s mixing hinted by the CDF and D0 data and the recent UTfit analysis, we update our 2006 analysis of par
ZEUS Collaboration, S. Chekanov
Photoproduction of beauty quarks in events with two jets and an electron associated with one of the jets has been studied with the ZEUS detector at HERA using an integrated luminosity of 120pb^-1. The fractions of events containing b quarks, and also of events containing c quarks, were extracted from a likelihood fit using variables sensitive to electron ide
An intense state of hard X-ray emission of Cyg X-1 observed by INTEGRAL coincident with TeV measurements
astro-phJ. Malzac, P. Lubinski, A. A. Zdziarski, M. Cadolle Bel
We present INTEGRAL light curves and spectra of the black-hole binary Cyg X-1 during a bright event that occurred in 2006 September, and which was simultaneous with a detection at 0.15-1 TeV energies by the MAGIC telescope. We analyse the hard X-ray emission from 18 to 700 keV with the INTEGRAL data taken on 2006 September 24-26. We present the light curves
T. Appourchaux, P. Liewer, M. Watt, D. Alexander
The POLAR Investigation of the Sun (POLARIS) mission uses a combination of a gravity assist and solar sail propulsion to place a spacecraft in a 0.48 AU circular orbit around the Sun with an inclination of 75 degrees with respect to solar equator. This challenging orbit is made possible by the challenging development of solar sail propulsion. This first exte
Effect of anisotropy on the ground-state magnetic ordering of the spin-one quantum $J_{1}^{XXZ}$--$J_{2}^{XXZ}$ model on the square lattice
cond-mat.str-elR F Bishop, P H Y Li, R Darradi, J Richter
We study the zero-temperature phase diagram of the $J_{1}^{XXZ}$--$J_{2}^{XXZ}$ Heisenberg model for spin-1 particles on an infinite square lattice interacting via nearest-neighbour ($J_1 \equiv 1$) and next-nearest-neighbour ($J_2 > 0$) bonds. Both bonds have the same $XXZ$-type anisotropy in spin space. The effects on the quasiclassical Néel-ordered and co
Ehud Fuchs, Michael Kroyter
We construct mappings that send solutions of the cubic and non-polynomial open superstring field theories to each other. We prove that the action is invariant under the maps and that gauge orbits are mapped into gauge orbits. It follows that the perturbative spectrum around solutions is the same in both theories. The mappings also preserve the string field r
Alessandra Frabetti
These are the notes of five lectures given at the Summer School {\em Geometric and Topological Methods for Quantum Field Theory}, held in Villa de Leyva (Colombia), July 2--20, 2007. The lectures are meant for graduate or almost graduate students in physics or mathematics. They include references, many examples and some exercices. The content is the followin
Configuration mixing of angular-momentum and particle-number projected triaxial HFB states using the Skyrme energy density functional
nucl-thM. Bender, P. -H. Heenen
We present a method based on mean-field states generated by triaxial quadrupole constraints which are projected on particle number and angular momentum and mixed by the generator coordinate method on the quadrupole moment. This method is equivalent to a seven-dimensional GCM calculation, mixing all five degrees of freedom of the quadrupole operator and the g
Bikramjit Das, Sidney I. Resnick
Multivariate extreme value theory assumes a multivariate domain of attraction condition for the distribution of a random vector. This necessitates that each component satisfies a marginal domain of attraction condition. An approximation of the joint distribution of a random vector obtained by conditioning on one of the components being extreme was developed
Relativistic, QED and nuclear effects in highly charged ions revealed by resonant electron-ion recombination in storage rings
physics.atom-phStefan Schippers
Dielectronic recombination (DR) of few-electron ions has evolved into a sensitive spectroscopic tool for highly charged ions. This is due to technological advances in electron-beam preparation and ion-beam cooling techniques at heavy-ion storage rings. Recent experiments prove unambiguously that DR collision spectroscopy has become sensitive to 2nd order QED
V. V. Kiselev
Exotic states in the charmonium family are systematically treated in the framework of simplest model with an effective coulomb-like interaction of heavy quark and antiquark in the presence of static excitation of quark-gluon modes responsible for a nonperturbative term of potential, which provides with the confinement of quarks, in terms of bag over the thre
Alexandru Dimca
We introduce in this paper a hypercohomology version of the resonance varieties and obtain some relations to the characteristic varieties of rank one local systems on a smooth quasi-projective complex variety $M$, see Theorem (3.1) and Corollaries (3.2) and (4.2). A logarithmic resonance variety is also considered in Proposition (4.5). As an application, we
Effect of pressure on the superconducting critical temperature of La[O_{0.89}F_{0.11}]FeAs and Ce[O_{0.88}F_{0.12}]FeAs
cond-mat.supr-conD. A. Zocco, J. J. Hamlin, R. E. Baumbach, M. B. Maple
We have performed several high-pressure resistivity experiments on the recently discovered superconductors La[O_{0.89}F_{0.11}]FeAs and Ce[O_{0.88}F_{0.12}]FeAs. At ambient pressure, these materials have superconducting onset temperatures T_c of 28 K and 44 K, respectively. While the T_c of La[O_{0.89}F_{0.11}]FeAs goes through a maximum between 10-68 kbar,
V. Potocek, A. Gabris, T. Kiss, I. Jex
Shenvi, Kempe and Whaley's quantum random-walk search (SKW) algorithm [Phys. Rev. A 67, 052307 (2003)] is known to require $O(\sqrt N)$ number of oracle queries to find the marked element, where $N$ is the size of the search space. The overall time complexity of the SKW algorithm differs from the best achievable on a quantum computer only by a constant f
C. Di Franco, M. Paternostro, M. S. Kim
We demonstrate that perfect state transfer can be achieved using an engineered spin chain and clean local end-chain operations, without requiring the initialization of the state of the medium nor fine tuning of control-pulses. This considerably relaxes the prerequisites for obtaining reliable transfer of quantum information across interacting-spin systems. M
Michael Snyder, Jonathan Frederick
This investigation describes and demonstrates a novel technique for the visualization of magnetic fields. Two ferrofluid Hele-Shaw cells have been constructed to facilitate the imaging of magnetic field lines. We deduce that magnetically induced photonic band gap arrays similar to electrostatic liquid crystal operation are responsible for the photographed im
Supernovae in Early-Type Galaxies: Directly Connecting Age and Metallicity with Type Ia Luminosity
astro-phJ. S. Gallagher, P. M. Garnavich, N. Caldwell, R. P. Kirshner
We have obtained optical spectra of 29 early-type (E/S0) galaxies that hosted type Ia supernovae (SNe Ia). We have measured absorption-line strengths and compared them to a grid of models to extract the relations between the supernova properties and the luminosity-weighted age/composition of the host galaxies. The same analysis was applied to a large number
Robert B. Gramacy, Herbert K. H. Lee
Computer experiments are often performed to allow modeling of a response surface of a physical experiment that can be too costly or difficult to run except using a simulator. Running the experiment over a dense grid can be prohibitively expensive, yet running over a sparse design chosen in advance can result in obtaining insufficient information in parts of
J. -P. Kownacki
In this paper, robustness of planar trivalent random graphs to targeted attacks of highest connected nodes is investigated using numerical simulations. It is shown that these graphs are relatively robust. The nonrandom node removal process of targeted attacks is also investigated as a special case of non-uniform site percolation. Critical exponents are calcu
Tara Brendle, Allen Hatcher
The main result in this paper is that the space of all smooth links in Euclidean 3-space isotopic to the trivial link of n components has the same homotopy type as its finite-dimensional subspace consisting of configurations of n unlinked Euclidean circles (the "rings" in the title). There is also an analogous result for spaces of arcs in upper half-
Mu-in Park
The complete non-linear three-dimensional Einstein gravity with gravitational Chern-Simons term and cosmological constant are studied in dreibein formulation. The constraints and their algebras are computed in an explicit form. From counting the number of first and second class constraints, the number of dynamical degrees of freedom, which equals to the numb
B. Pire, C. Roiesnel, L. Szymanowski, S. Wallon
We critically examine the question of scaling of the Deep Inelastic Scattering process in the medium Bjorken x region on a scalar boson in the framework of the AdS/QCD correspondence. To get the right polarization structure of the forward electroproduction amplitude, we show that one needs to add (at least) the scalar to scalar and scalar to vector hadronic
Spyridon Dendrinos, Norberto Laghi, James Wright
We prove sharp $L^p-L^q$ estimates for averaging operators along general polynomial curves in two and three dimensions. These operators are translation-invariant, given by convolution with the so-called affine arclength measure of the curve and we obtain universal bounds over the class of curves given by polynomials of bounded degree. Our method relies on a
Jan Manschot
Invariance under modular transformations and spectral flow restrict the possible spectra of superconformal field theories (SCFT). This paper presents a technique to calculate the number of constraints on the polar spectra of N=(2,2) and N=(4,0) SCFT's by analyzing the elliptic genus. The polar spectrum corresponds to the principal part of a Laurent expan
Heikki J. Tikanmäki
The one dimensional distribution of a Lévy process is not known in general even though its characteristic function is given by the famous Lévy-Khinchine theorem. This article gives an exact series representation for the one dimensional distribution of a Lévy process satisfying certain moment conditions. Moreover, this work clarifies an old result by Cramér o
A common model for superluminal propagation in absorbing atomic media and lossy metastructures
physics.opticsP. Chamorro-Posada, F. J. Fraile-Pelaez
We analyse the superluminal propagation of narrow-band pulses at resonances in dissipative media. The output waveform is an attenuated, undistorted, time-advanced version of the input which can be interpreted as the result of the interference of two scaled replicas of the input having a positive relative delay. The proposed analysis applies both to the propa
Ulrik Brandes, Martin Hoefer, Bobo Nick
In this paper we extend a popular non-cooperative network creation game (NCG) to allow for disconnected equilibrium networks. There are n players, each is a vertex in a graph, and a strategy is a subset of players to build edges to. For each edge a player must pay a cost α, and the individual cost for a player represents a trade-off between edge costs and sh
Fedor V. Prigara
It is shown that a sufficiently strong external electric field causes a decrease in the transition temperature of ferroelectric, antiferroelectric, and metal-insulator transitions. The temperature dependence of the critical electric field suppressing a low-temperature phase is obtained. The relation between the low-temperature charge gap (the band gap) in th
T. L. Riethmueller, S. K. Solanki, A. Lagg
This work aims to constrain the physical nature of umbral dots (UDs) using high-resolution spectropolarimetry. Full Stokes spectra recorded by the spectropolarimeter on Hinode of 51 UDs in a sunspot close to the disk center are analyzed. The height dependence of the temperature, magnetic field vector, and line-of-sight velocity across each UD is obtained fro
Vasily Ogryzko
I compare two quantum-theoretical approaches to the phenomenon of adaptive mutations, termed here Q-cell and Q-genome. I use 'fluctuation trapping' model as a general framework. I introduce notions of R-error and D-error and argue that the 'fluctuation trapping' model has to employ a correlation between the R- and D- errors. Further, I compar
S. Matyjaskiewicz, M. H. Szymanska, K. Goral
Fast sweep projection onto Feshbach molecules has been widely used as a probe of fermionic condensates. By determining the exact dynamics of a pair of atoms in time varying magnetic fields, we calculate the number of condensed and noncondensed molecules created after fast magnetic field sweeps from the BCS to the BEC side of the resonances in $^{40}$K and $^
Kaifu Luo, Santtu T. T. Ollila, Ilkka Huopaniemi, Tapio Ala-Nissila
We determine the scaling exponents of polymer translocation (PT) through a nanopore by extensive computer simulations of various microscopic models for chain lengths extending up to N=800 in some cases. We focus on the scaling of the average PT time $τ\sim N^α$ and the mean-square change of the PT coordinate $<s^2(t)> \sim t^β$. We find $α=1+2ν$ and $β=2/α$
Gustavo Dotti, Reinaldo J. Gleiser, Ignacio Francisco Ranea-Sandoval, Héctor Vucetich
In this paper we consider the possible existence of unstable axisymmetric modes in Kerr space times, resulting from exponentially growing solutions of the Teukolsky equation. We describe a transformation that casts the radial equation that results upon separation of variables in the Teukolsky equation, in the form of a Schrödinger equation, and combine the p
Electric field-induced spin textures in a superlattice with Rashba and Dresselhaus spin-orbit coupling
cond-mat.mes-hallD. V. Khomitsky
The DC charge current, field-induced spin polarization and spin textures are studied in the 1D gated superlattice with both fixed and varying Rashba and Dresselhaus contributions to spin-orbit coupling. It is found that a spin component with zero mean value can demonstrate non-vanishing field-induced spin texture in a superlattice cell which can be probed ex
Anjan Kumar Chandra, Jun-ichi Inoue, Bikas K. Chakrabarti
We consider a long-range Ising antiferromagnet (LRIAF) put in a transverse field. Applying quantum Monte Carlo method, we study the variation of order parameter (spin correlation in Trotter time direction), susceptibility and average energy of the system for various values of the transverse field at different temperatures. The antiferromagnetic order is seen
Juerg Froehlich, Antti Knowles, Simon Schwarz
In the mean-field limit the dynamics of a quantum Bose gas is described by a Hartree equation. We present a simple method for proving the convergence of the microscopic quantum dynamics to the Hartree dynamics when the number of particles becomes large and the strength of the two-body potential tends to 0 like the inverse of the particle number. Our method i
Le-Huy Nguyen, Rajesh R. Parwani
We study the effects of an information-theoretically motivated nonlinear correction to the Wheeler-deWitt equation in the minisuperspace scheme for flat, $k=0$, Friedmann-Robertson-Walker (FRW) universes. When the only matter is a cosmological constant, the nonlinearity can provide a barrier that screens the original Big Bang, leading to the quantum creation
Interference bands in decays of doubly-charged Higgs bosons to dileptons in the minimal type-II seesaw model at the TeV scale
hep-phPing Ren, Zhi-zhong Xing
The dileptonic decays of doubly-charged Higgs bosons H^{\pm\pm} are investigated in the minimal type-II seesaw model with one Higgs triplet Δand one heavy Majorana neutrino N_1 at the TeV scale. We show that the branching ratios {\cal B}(H^{\pm\pm} \to l^\pm_αl^\pm_β) depend not only on the mass and mixing parameters of three light neutrinos ν_i (for i=1,2,3
V. G. Gurzadyan, A. A. Kocharyan
The properties of geodesics flow are studied in a Friedmann-Robertson-Walker metric perturbed due to the inhomogeneities of matter. The basic, averaged Jacobi equation is derived, which reveals that the low density regions (voids) are able to induce hyperbolicity, even if the global curvature of the Universe is zero or slightly positive. It is shown that the
S. Zenitani, M. Hesse
We investigate properties of the reconnecting current layer in relativistic pair plasma reconnection. We found that the current layer self-regulates its thickness when the current layer runs out current carriers, and so relativistic reconnection retains a fast reconnection rate. Constructing a steady state Sweet-Parker model, we discuss conditions for the cu
Bálint Farkas
For a given bi-continuous semigroup T on a Banach space X we define its adjoint on an appropriate closed subspace X^o of the norm dual X'. Under some abstract conditions this adjoint semigroup is again bi-continuous with respect to the weak topology (X^o,X). An application is the following: For K a Polish space we consider operator semigroups on the spac
A. C. Jacko, J. O. Fjaerestad, B. J. Powell
Discoveries of ratios whose values are constant within broad classes of materials have led to many deep physical insights. The Kadowaki-Woods ratio (KWR) compares the temperature dependence of a metal's resistivity to that of its heat capacity; thereby probing the relationship between the electron-electron scattering rate and the renormalisation of the e
Vladimir V. Bazhanov, Zengo Tsuboi
We develop Yang-Baxter integrability structures connected with the quantum affine superalgebra Uq(\hat sl(2|1)). Baxter's Q-operators are explicitly constructed as supertraces of certain monodromy matrices associated with (q-deformed) bosonic and fermionic oscillator algebras. There are six different Q-operators in this case, obeying a few fundamental fu
Meng Chen
We extend Kollar's technique to look for an explicit function h(n) with phi_m birational onto its image for all integers $m\geq h(n)$ and for all n-dimensional nonsingular projective varieties of general type.
Automorphisms of Coxeter groups and Lusztig's conjectures for Hecke algebras with unequal parameters
math.RTCédric Bonnafé
Let $(W,S)$ be a Coxeter system, let $G$ be a finite solvable group of automorphisms of $(W,S)$ and let $φ$ be a weight function which is invariant under $G$. Let $φ_G$ denote the weight function on $W^G$ obtained by restriction from $φ$. The aim of this paper is to compare the ${\mathbf{a}}$-function, the set of Duflo involutions and the Kazhdan-Lusztig cel
Primordial matter density contrast and the size of the very early universe in the Quantum Big Bang theory of the cosmological constant
gr-qcBudh Ram
We calculate the amount of primordial matter density contrast and the size of the very early universe in the recent Quantum Big Bang theory [arXiv:0705.4549 [gr-qc](2007)] of the cosmological constant. We obtain $(δρ/ρ)_M = 1.75 \times 10^{-5}$, {\it without} the introduction of an adjustable free parameter. Harrison-Zel'dovich $k$-dependence with $A = 6
Elmo Tempel, Jaan Einasto, Maret Einasto, Enn Saar
Aims. We use the 2dF Galaxy Redshift Survey to derive the luminosity function (LF) of the first-ranked (brightest) group/cluster galaxies, the LF of second-ranked, satellite and isolated galaxies, and the LF of groups of galaxies. Methods. We investigate the LFs of different samples in various environments: in voids, filaments, superclusters and supercluster
Study of Nuclear Suppression at Large Forward Rapidities in d-Au Collisions at Relativistic and Ultrarelativistic Energies
hep-phJ. Nemchik, V. Petracek, I. K. Potashnikova, M. Sumbera
We study a strong suppression of the relative production rate (d-Au)/(p-p) for inclusive high-pT hadrons of different species at large forward rapidities (large Feynman xF). The model predictions calculated in the light-cone dipole approach are in a good agreement with the recent measurements by the BRAHMS and STAR Collaborations at the BNL Relativistic Heav
Shuichiro Yokoyama, Jiro Soda
We present a new mechanism for generating primordial statistical anisotropy of curvature perturbations. We introduce a vector field which has a non-minimal kinetic term and couples with a waterfall field in hybrid inflation model. In such a system, the vector field gives fluctuations of the end of inflation and hence induces a subcomponent of curvature pertu
Mott Phase in Polarized Two-component Atomic Fermi Lattice Gas:A Playground for S=1/2 Heisenberg Model in Magnetic Field
cond-mat.str-elM. Machida, M. Okumura, S. Yamada, T. Deguchi
We investigate effects of pseudo-spin population imbalance on Mott phases in 1D trapped two-component atomic Fermi gases loaded on optical lattices based on the repulsive Hubbard model in harmonic traps. By using the density matrix renormalization group method, we numerically calculate density profiles of each component and clarify the pseudo-spin magnetism.
Abraham I Harte
A notion of geometric symmetry is introduced that generalizes the classical concepts of Killing fields and other affine collineations. There is a sense in which flows under these new vector fields minimize deformations of the connection near a specified observer. Any exact affine collineations that may exist are special cases. The remaining vector fields can
C. Martin Gaskell, Rene W. Goosmann
Velocity-resolved reverberation mapping suggests that the broad-line regions (BLRs) of AGNs can have significant net inflow. We use the STOKES radiative transfer code to show that electron and Rayleigh scattering off the BLR and torus naturally explains the blueshifted profiles of high-ionization lines and the ionization dependence of the blueshifts. This re
Characterization of jacobian Newton polygons of plane branches and new criteria of irreducibility
math.AGEvelia R. García Barroso, Janusz Gwoździewicz
In this paper we characterize, in two different ways, the Newton polygons which are jacobian Newton polygons of a branch. These characterizations give in particular combinatorial criteria of irreducibility for complex series in two variables and necessary conditions which a complex curve has to satisfy in order to be the discriminant of a complex plane branc
Plasmons in the presence of Tamm-Shockley states with Rashba splitting at noble metal surfaces
cond-mat.mes-hallA. M. Farid, E. G. Mishchenko
Au(111) or similar noble metal surfaces feature Tamm-Shockley surface states that are known to possess considerable spin-orbit splitting of the Rashba type of order $Δ=0.1$ eV. When interacting with an electromagnetic field such states are expected to have resonances when the frequency of the field is near the energy of the spin-orbit splitting $Δ$. These re
Israel Nowik, Israel Felner, V. P. S. Awana, Arpita Vajpayee
We report on the magnetic behavior of oxygen deficient LaFeAsO1-x (x-0.10) compound, prepared by one-step synthesis, which crystallizes in the tetragonal (S.G. P4/nmm) structure at room temperature. Resistivity measurements show a strong anomaly near 150 K, which is ascribed to the spin density wave (SDW) instability. On the other hand, dc magnetization data
Extracting Angular Diameter Distance and Expansion Rate of the Universe from Two-dimensional Galaxy Power Spectrum at High Redshifts: Baryon Acoustic Oscillation Fitting versus Full Modeling
astro-phMasatoshi Shoji, Donghui Jeong, Eiichiro Komatsu
We present a method for extracting the angular diameter distances, $D_A$, and the expansion rates, $H$, of the universe from the {\it two-dimensional} Baryon Acoustic Oscillations (BAO) in the galaxy power spectrum. Our method builds upon the existing algorithm called the "fit-and-extract" (FITEX) method, which allows one to extract only $D_A^2/H$ fr
Steven P. Kerckhoff, Peter A. Storm
We describe a family of 4-dimensional hyperbolic orbifolds, constructed by deforming an infinite volume orbifold obtained from the ideal, hyperbolic 24-cell by removing two walls. This family provides an infinite number of infinitesimally rigid, infinite covolume, geometrically finite discrete subgroups of the isometry group of hyperbolic 4-space. It also le
Andrzej Baran, Aurel Bulgac, Michael McNeil Forbes, Gaute Hagen
Broyden's method, widely used in quantum chemistry electronic-structure calculations for the numerical solution of nonlinear equations in many variables, is applied in the context of the nuclear many-body problem. Examples include the unitary gas problem, the nuclear density functional theory with Skyrme functionals, and the nuclear coupled-cluster theor
Can antiferromagnetism and superconductivity coexist in the high-field paramagnetic superconductor Nd(O,F)FeAs?
cond-mat.supr-conC. Tarantini, A. Gurevich, D. C. Larbalestier, Z. A. Ren
We present measurements of the temperature and field dependencies of the magnetization M(T,H) of Nd(O0.89F0.11)FeAs at fields up to 33T, which show that superconductivity with the critical temperature Tc ~ 51K cannot coexist with antiferromagnetic ordering. Although M(T,H) at 55 < T < 140K exhibits a clear Curie-Weiss temperature dependence corresponding to
Peter Abramenko, Hendrik Van Maldeghem
We show that, if a building is endowed with its complete system of apartments, and if each panel is contained in at least four chambers, then the intersection of two apartments can be any convex subcomplex contained in an apartment. This combinatorial result is particularly interesting for lower dimensional convex subcomplexes of apartments, where we definit
Alexei Poltoratski, Christian Remling
We study several related aspects of reflectionless Jacobi matrices. Our first set of results deals with the singular part of reflectionless measures. We then introduce and discuss Lyapunov exponents, density of states measures, and other related quantities in a \textit{general} setting. This is related to the previous material because the density of states m
M. Nozar, C. Salgado, D. P. Weygand, L. Guo
A search for exotic mesons in the $π^{+}π^{+}π^{-}$ system photoproduced by the charge exchange reaction $γp\to π^{+}π^{+}π^{-}(n)$ was carried out by the CLAS collaboration at Jefferson Lab. A tagged-photon beam with energies in the 4.8 to 5.4 GeV range, produced through bremsstrahlung from a 5.744 GeV electron beam, was incident on a liquid-hydrogen target
A. W. Thomas, Jefferson Lab
The twenty years since the announcement of the proton spin crisis by the European Muon Collaboration has seen tremendous progress in our knowledge of the distribution of spin within the proton. The problem is reviewed, beginning with the original data and the suggestion that polarized gluons may play a crucial role in resolving the problem through the U(1) a
Vladimir Voevodsky
These lecture notes cover four topics. There is a proof of the fact that the functors represented by the motivic Eilenberg-Maclane spaces on the motivic homotopy category coincide with the motivic cohomology defined in terms of the motivic complexes. There is a description of the equivariant motivic homotopy category for a finite flat group scheme (over a no
Hirotaka Yoshino, Kohei Onda
We present the plane-symmetric solitonlike solutions of magnetostatic equilibria by solving the nonlinear Grad-Shafranov (GS) equation numerically. The solutions have solitonlike and periodic structures in the $x$ and $y$ directions, respectively, and $z$ is the direction of plane symmetry. Although such solutions are unstable against the numerical iteration
First-Principles Studies of the Metallization and the Equation of State of Solid Helium
physics.comp-phSaad Antoun Khairallah, Burkhard Militzer
The insulator-to-metal transition in solid helium at high pressure is studied with first-principles simulations. Diffusion quantum Monte Carlo (DMC) calculations predict that the band gap closes at a density of 21.3 g/cc and a pressure of 25.7 terapascals, which is 20% higher in density and 40% higher in pressure than predicted by density functional calculat
Vladimir Voevodsky
In this paper we define the triangulated category of motives over a simplicial scheme. The morphisms between the Tate objects in this category compute the motivic cohomology of the underlying scheme. In the last section we consider the special case of "embedded" simplicial schemes, which correspond to the subsheaves of the constant sheaf and naturall
F. C. Wellstood, Z. Kim, B. Palmer
We analyze the behavior of a Cooper Pair Box (CPB) that is coupled to charge fluctuators that reside in the dielectric barrier layer in the box's ultra-small tunnel junction. We derive the Hamiltonian of the combined system and find the coupling between the CPB and the fluctuators as well as a coupling between the fluctuators that is due to the CPB. We t
Electron Spin Relaxation and 39K Pulsed ENDOR Studies on Cr5+ doped K3NbO8 at 9.7 and 240 GHz
physics.chem-phS. Nellutla, G. W. Morley, M. Pati, N. S. Dalal
Cr^5+ doped K_3NbO_8, considered to be useful as a electron spin qubit, has been investigated by pulsed X-band (~9.7 GHz) and 240 GHz electron paramagnetic resonance and electron nuclear double resonance (ENDOR). Comparison of the low temperature electronic spin-lattice relaxation rate 1/T_1 at 9.7 and 240 GHz shows that it is 250 times faster at 240 GHz tha
G. Biroli, J. -P. Bouchaud, A. Cavagna, T. S. Grigera
Although several theories relate the steep slowdown of glass formers to increasing spatial correlations of some sort, standard static correlation functions show no evidence for this. We present results that reveal for the first time a qualitative thermodynamic difference between the high temperature and deeply supercooled equilibrium glass-forming liquid: th
Vasanthan Raghavan, Akbar Sayeed, Venu Veeravalli
The focus of this paper is on spatial precoding in correlated multi-antenna channels, where the number of independent data-streams is adapted to trade-off the data-rate with the transmitter complexity. Towards the goal of a low-complexity implementation, a structured precoder is proposed, where the precoder matrix evolves fairly slowly at a rate comparable w
Yoichi Tanaka, Norio Kawakami, Akira Oguri
We study the transport through side-coupled double quantum dots, connected to normal and superconducting (SC) leads with a T-shape configuration. We find, using the numerical renormalization group, that the Coulomb interaction suppresses SC interference in the side dot, and enhances the conductance substantially in the Kondo regime. This behavior stands in t
Matthew Hedden, Liam Watson
We determine a wide class of knots, which includes unknotting number one knots, within which Khovanov homology detects the unknot. A corollary is that the Khovanov homology of many satellite knots, including the Whitehead double, detects the unknot.
Jesse Johnson
We show that the number of stabilizations needed to interchange the handlebodies of a Heegaard splitting of a closed 3-manifold by an isotopy is bounded below by the smaller of twice its genus or half its Hempel distance. This is a combinatorial version of a proof by Hass, Thompson and Thurston of a similar theorem, but with an explicit bound in terms of dis
I. Andruchow, Sergio A. Cellone, Gustavo E. Romero
We study the incidence of the underlying host galaxy light on the measured optical linear polarization of blazars. Our methodology consists of the implementation of simulated observations obtained under different atmospheric conditions, which are characterised by the Gaussian $σ$ of the seeing function. The simulated host plus active nucleus systems span bro
R. S. Bussmann, D. Narayanan, Y. L. Shirley, S. Juneau
We present observations made with the 10m Heinrich Hertz Sub-Millimeter Telescope of HCN (3-2) emission from a sample of 30 nearby galaxies ranging in infrared luminosity from 10^10 - 10^12.5 L_sun and HCN (3-2) luminosity from 10^6 - 10^9 K km s^-1 pc^2. We examine the correlation between the infrared luminosity and HCN (3-2) luminosity and find that the be
Matthew Hedden
We prove that the Khovanov homology of the 2-cable detects the unknot. A corollary is that Khovanov's categorification of the 2-colored Jones polynomial detects the unknot.
A new method for determining the sensitivity of X-ray imaging observations and the X-ray number counts
astro-phA. Georgakakis, K. Nandra, E. S. Laird, J. Aird
We present a new method for determining the sensitivity of X-ray imaging observations, which correctly accounts for the observational biases that affect the probability of detecting a source of a given X-ray flux, without the need to perform a large number of time consuming simulations. We use this new technique to estimate the X-ray source counts in differe
Parameterization of Theoretical Methods in the Calculation of Nano-expulsion Energies
physics.chem-phAned de Leon
The present work encompasses an investigation of the adsorption properties of small dimer species onto a zigzag single walled carbon nanotube (ZNT for short). To perform this analysis we have considered the zigzag (8, 0) system with a length of 13.5 angstroms that has a diameter of 6.3 angstroms. Various theoretical DFT and ab initio approaches were used to
B. Alver, M. Baker, C. Loizides, P. Steinberg
``Glauber'' models are used to calculate geometric quantities in the initial state of heavy ion collisions, such as impact parameter, number of participating nucleons and initial eccentricity. The four RHIC experiments have different methods for Glauber Model calculations, leading to similar results for various geometric observables. In this document
Francesco Buccheri, Davide Fioravanti
We exactly compute the energy density of the integrable O(n) non-linear sigma model as a convergent series. This series is specifically analysed for the very important O(6) symmetry, since it was suggested to result as a peculiar limit of the AdS string theory by Alday and Maldacena [1]. In this respect, the O(6) model gives also refined confirmations and pr
First VLTI infrared spectro-interferometry on GCIRS 7 - Characterizing the prime reference source for Galactic center observations at highest angular resolution
astro-phJ. -U. Pott, A. Eckart, A. Glindemann, S. Kraus
Investigating the environment of the massive black hole SgrA* at the center of the Galaxy requires the highest angular resolution available to avoid source confusion and to study the physical properties of the individual objects. GCIRS7 has been used as wavefront and astrometric reference. Our studies investigate, for the first time, its properties at 2&10um
Bogdan Cristea
Mean value and cross-covariance function of chaotic binary sequences are evaluated for chaotic maps with specific properties. We also take into account the effect of fixed- and floating-point representations on statistical properties of chaotic generators. Thus, one is able to obtain possible candidates for pseudo-random binary sequences generation. Results
Werner Koch, Frank Großmann, Jürgen T. Stockburger, Joachim Ankerhold
The exact stochastic decomposition of non-Markovian dissipative quantum dynamics is combined with the time-dependent semiclassical initial value formalism. It is shown that even in the challenging regime of moderate friction and low temperatures, where non-Markovian effects are substantial, this approach allows for the accurate description of dissipative dyn
Michael Robinson
It is well known that for many semilinear parabolic equations there is a global attractor which has a cell complex structure with finite dimensional cells. Additionally, many semilinear parabolic equations have equilibria with finite dimensional unstable manifolds. In this article, these results are unified to show that for a specific parabolic equation on a
The energy partitioning of non-thermal particles in a plasma: or the Coulomb logarithm revisited
physics.plasm-phRobert L. Singleton, Lowell S. Brown
The charged particle stopping power in a highly ionized and weakly to moderately coupled plasma has been calculated to leading and next-to-leading order by Brown, Preston, and Singleton (BPS). After reviewing the main ideas behind this calculation, we use a Fokker-Planck equation derived by BPS to compute the electron-ion energy partitioning of a charged par
Numerical Study of Energy Loss by a Nanomechanical Oscillator Coupled to a Cooper Pair Box
cond-mat.supr-conRakesh P. Tiwari, D. Stroud
We calculate the dynamics of a nanomechanical oscillator (NMO) coupled capacitively to a Cooper pair box (CPB), by solving a stochastic Schrodinger equation with two Lindblad operators. Both the NMO and the CPB are assumed dissipative, and the coupling is treated within the rotating wave approximation. We show numerically that, if the CPB decay time is small
Baojiu Li, John D. Barrow, David F. Mota, HongSheng Zhao
We propose a method to study and constrain modified gravity theories for dark matter using CMB temperature anisotropies and polarization. We assume that the theories considered here have already passed the matter power-spectrum test of large-scale structure. With this requirement met, we show that a modified gravity theory can be specified by parametrizing t
Davide Batic, Manuel Sandoval
In this article we show for the first time the role played by the hypergeneralized Heun equation (HHE) in the context of Quantum Field Theory in curved space-times. More precisely, we find suitable transformations relating the separated radial and angular parts of a massive Dirac equation in the Kerr-Newman-deSitter metric to a HHE.
The photospheric solar oxygen project: I. Abundance analysis of atomic lines and influence of atmospheric models
astro-phElisabetta Caffau, Hans-G. Ludwig, Matthias Steffen, Thomas R. Ayres
The solar oxygen abundance has undergone a major downward revision in the last decade, the most noticeable one being the update including 3D hydrodynamical simulations to model the solar photosphere. Up to now, such an analysis has been carried out only by one group using one radiation-hydrodynamics code. We investigate the photospheric oxygen abundance cons
John Dubinski
I begin with a brief history of N-body simulation and visualization and then go on to describe various methods for creating images and animations of modern simulations in cosmology and galactic dynamics. These techniques are incorporated into a specialized particle visualization software library called MYRIAD that is designed to render images within large pa
J. A. Tjon, S. J. Wallace
An eikonal expansion is used to provide systematic corrections to the eikonal approximation through order $1/k^2$, where $k$ is the wave number. Electron wave functions are obtained for the Dirac equation with a Coulomb potential. They are used to investigate distorted-wave matrix elements for quasi-elastic electron scattering from a nucleus. A form of effec
Instabilities of MHD Waves Produced by Coupling of Rotation and Gradient of Magnetic Field and its Possible Application in the Galactic Central Region
astro-phIpsita Das, Ramaprosad Bondyopadhaya
An analysis of MHD wave propagating in a gravitating and rotating medium permeated by non-uniform magnetic field has been done. It has been found that the Gradient of Magnetic Field when coupled with Rotation becomes capable to generate few instabilities (Temporal or Spatial) leading to the damping or amplification of MHD waves. The Jean's criterion is n
Luciana Guimaraes
This paper presents elements that form the structure of a network of data using secure stable and mature technologies that meet the requirement of having code free. The principle would be conflicting code open Tuesday where he wants to keep maximum control over the data but is already evidence that open source does not hide the famous backdoor possible in cl