February 2007 arXiv papers — page 12
Showing 1,101–1,200 of 4,165 papers
C. E. Rodríguez Torres, F. Golmar, A. F. Cabrera, L. A. Errico
Transparent pure and Cu-doped (2.5, 5 and 10 at. %) anatase TiO2 thin films were grown by pulsed laser deposition technique on LaAlO3 substrates. The samples were structurally characterized by X-ray absorption spectroscopy and X-ray diffraction. The magnetic properties were measured using a SQUID. All films have a FM-like behaviour. In the case of the Cu-dop
B. A. Tay, G. Ordonez
We derive an exact Markovian kinetic equation for an oscillator linearly coupled to a heat bath, describing quantum Brownian motion. Our work is based on the subdynamics formulation developed by Prigogine and collaborators. The space of distribution functions is decomposed into independent subspaces that remain invariant under Liouville dynamics. For integra
G. J. Milburn, C. A. Holmes, L. M. Kettle, H. S. Goan
We give a quantum master equation description of the measurement scheme based on a coplanar microwave cavity capacitively coupled to nano mechanical resonator. The system exhibits a rich bifurcation structure that is analogous to sub/second harmonic generation in nonlinear optics. We show how it may be configured as a bifurcation amplifier transducer for wea
Melinda Y. Han, Barbaros Oezyilmaz, Yuanbo Zhang, Philip Kim
We investigate electronic transport in lithographically patterned graphene ribbon structures where the lateral confinement of charge carriers creates an energy gap near the charge neutrality point. Individual graphene layers are contacted with metal electrodes and patterned into ribbons of varying widths and different crystallographic orientations. The tempe
P. Fazekas, K. Penc, K. Radnoczi, N. Barisic
BaVS3 is a moderately correlated d-electron system with a rich phase diagram. To construct the corresponding minimal electronic model, one has to decide which d-states are occupied, and to which extent. The ARPES experiment presented here shows that the behavior of BaVS3 is governed by the coexistence of wide-band (A_1g) and narrow-band (twofold degenerate E
Radio-frequency magnetic response of vortex lattices undergoing structural transformations
cond-mat.supr-conR. Prozorov, V. G. Kogan, M D. Vannette, S. L. Bud'ko
We report a clear anomaly in the rf response of a tunnel-diode resonator measured in borocarbide crystals in dc fields along the $c-$axis. We associate the anomaly in the dynamic magnetic susceptibility, $χ$, with a structural transition in the vortex lattice. $χ$ is sensitive to the Campbell penetration depth $λ_{C}$ of the rf perturbation into the mixed st
Density matrix theory of transport and gain in quantum cascade lasers in a magnetic field
cond-mat.mes-hallIvana Savic, Nenad Vukmirovic, Zoran Ikonic, Dragan Indjin
A density matrix theory of electron transport and optical gain in quantum cascade lasers in an external magnetic field is formulated. Starting from the general quantum kinetic treatment, we describe the intra- and inter-period electron dynamics at the non-Markovian, Markovian and Boltzmann approximation levels. Interactions of electrons with longitudinal opt
Anja C. Andersen
Dust is formed in the expanding atmosphere during late stages of stellar evolution. Dust influences the dynamics and thermodynamics of the stellar atmosphere by its opacity. The dust opacity depends both on the optical properties of the grain material as well as on the amount of dust present. A rich source of information on some mineral phases of dust in AGB
F. Camilo, J. Reynolds, S. Johnston, J. P. Halpern
We have used the Parkes radio telescope to study the polarized emission from the anomalous X-ray pulsar XTE J1810-197 at frequencies of 1.4, 3.2, and 8.4 GHz. We find that the pulsed emission is nearly 100% linearly polarized. The position angle of linear polarization varies gently across the observed pulse profiles, varying little with observing frequency o
J. H. Groh, A. Damineli, D. J. Hillier
We present the results of a detailed spectroscopic analysis of 20 years of observations of AG Carinae using the radiative transfer code CMFGEN. Among the conclusions of this work, we highlight the importance of including time-dependent effects in the analysis of the full S Dor cycle. We obtained that the mass-loss rate is approximately constant during the co
Claude Carignan, Laurent Chemin, Tyler Foster
Carignan et al. (2006) recently presented an extended HI rotation curve (RC) of M31, using single dish observations from the 100m Effelsberg and Green Bank telescopes. These observations were motivated by a comparison with previous HI data from Braun (1991) which presented a decreasing rotation curve as a function of radius. The single dish data were obtaine
David Boyd, Tom Krajci, Jeremy Shears, Gary Poyner
During 2006 May the first confirmed superoutburst of the dwarf nova V337 Cygni was observed using unfiltered CCD photometry. The outburst reached a peak magnitude of 15.2 on May 22 and lasted 13 days before the object returned to quiescence at around magnitude 20. Time-series photometry revealed superhumps with a period of 0.07012 +/- 0.00033d and amplitude
Alberto Vallinotto, Scott Dodelson, Carlo Schimd, Jean-Philippe Uzan
Baryon Acoustic Oscillations (BAO) have recently been observed in the distribution of distant galaxies. The height and location of the BAO peak are strong discriminators of cosmological parameters. Here we consider the ways in which weak gravitational lensing distorts the BAO signal. We find two effects that can affect the height of the BAO peak in the corre
M. Baes, O. K. Sil'chenko, A. V. Moiseev, E. A. Manakova
We probe the stellar population age and metallicity distributions in nearby elliptical galaxies over the largest extension to date. Long-slit spectroscopy is made by using the spectrograph SCORPIO of the 6-m telescope of the Special Astrophysical Observatory of the Russian Academy of Sciencies. The Lick indices H-beta, Mg b, Fe5270, and Fe5335 are calculated
Andrew L. Haynes, Clare E. Parnell, Klaus Galsgaard, Eric R. Priest
The heating of the solar corona is likely to be due to reconnection of the highly complex magnetic field that threads throughout its volume. We have run a numerical experiment of an elementary interaction between the magnetic field of two photospheric sources in an overlying field that represents a fundamental building block of the coronal heating process. T
Application of the theory of Linear Singular Integral Equations and Contour Integration to Riemann Hilbert Problems for determination of new decoupled expressions of Chandrasekhar's X- and Y- functions for slab geometry in Radiative Transfer
astro-phRabindra Nath Das
In Radiative transfer, the intensities of radiation from the bounding faces of finite slab are obtained in terms of X- and Y- functions of Chandrasekhar . Those are non linear non homogeneous coupled integral equations . Those non linear integral equations are meromorphically extended to the complex plane to get linear non homogeneous coupled integral equati
Y. Liu, J. D. Richardson, J. W. Belcher, J. C. Kasper
We show that temperature anisotropies induced at a shock can account for interplanetary and planetary bow shock observations. Shocked plasma with enhanced plasma beta is preferentially unstable to the mirror mode instability downstream of a quasi-perpendicular shock and to the firehose instability downstream of a quasi-parallel shock, consistent with magneti
M. Vietri, L. Stella, G. Israel
Fast Quasi-Periodic Oscillations (QPOs, frequencies of $\sim 20 - 1840$ Hz) have been recently discovered in the ringing tail of giant flares from Soft Gamma Repeaters (SGRs), when the luminosity was of order $10^{41}-10^{41.5}$ erg/s. These oscillations persisted for many tens of seconds, remained coherent for up to hundreds of cycles and were observed over
R. Kandori, M. Tamura, N. Kusakabe, Y. Nakajima
We conducted wide-field JHKs imaging polarimetry toward NGC 2024. We found a prominent and extended polarized nebula over NGC 2024, and constrained the location of illuminating source of the nebula through the analysis of polarization vectors. A massive star, IRS 2b, is located in the center of the symmetric vector pattern. Five small polarized nebulae assoc
Realistic triaxial density--potential--force profiles for stellar systems and dark matter halos
astro-phBalsa Terzic, Benjamin J. Sprague
Popular models for describing the luminosity-density profiles of dynamically hot stellar systems (e.g., Jaffe, Hernquist, Dehnen) were constructed to match the deprojected form of de Vaucouleurs' $R^{1/4}$ light-profile. However, we now know that elliptical galaxies and bulges display a mass-dependent range of structural profiles. To compensate this, the
E. Lyratzi, E. Danezis, L. Č. Popović, M. S. Dimitrijević
Here is studied the presence of absorption components shifted to the violet or the red side of the main spectral line (satellite, or discrete absorption components, i.e. SACs or DACs), in Mg II resonance lines' regions in Be stars and their kinematical characteristics. Namely our objective is to check if exists a common physical structure for the atmosph
Kuenley Chiu, Steven P. Bamford, Andrew Bunker
Local and intermediate redshift (z~0.5) galaxy samples obey well correlated relations between the stellar population luminosity and maximal galaxy rotation that define the Tully-Fisher (TF) relation. Consensus is starting to be reached on the TF relation at z~0.5, but work at significantly higher redshifts is even more challenging, and has been limited by sm
Xing M. Wang
In this article, we continue to explore Probability Bracket Notation (PBN), proposed in our previous article. Using both Dirac vector bracket notation (VBN) and PBN, we define induced Hilbert space and induced sample space, and propose that there exists an equivalence relation between a Hilbert space and a sample space constructed from the same base observab
M. R. Swain, J. Bouwman, R. Akeson, S. Lawler
We report the spectroscopic detection of mid-infrared emission from the transiting exoplanet HD 209458b. Using archive data taken with the Spitzer/IRS instrument, we have determined the spectrum of HD 209458b between 7.46 and 15.25 microns. We have used two independent methods to determine the planet spectrum, one differential in wavelength and one absolute,
Gim Seng Ng, Tsampikos Kottos
The destruction of anomalous diffusion of the Harper model at criticality, due to weak nonlinearity $χ$, is analyzed. It is shown that the second moment grows subdiffusively as $<m_2> \sim t^α$ up to time $t^*\sim χ^γ$. The exponents $α$ and $γ$ reflect the multifractal properties of the spectra and the eigenfunctions of the linear model. For $t>t^*$, the an
Adaptive Optics Discovery of Supernova 2004ip in the Nuclear Regions of the Luminous Infrared Galaxy IRAS 18293-3413
astro-phS. Mattila, P. Vaisanen, D. Farrah, A. Efstathiou
We report a supernova discovery in Ks-band images from the NAOS CONICA adaptive optics (AO) system on the ESO Very Large Telescope (VLT). The images were obtained as part of a near-infrared search for highly-obscured supernovae in the nuclear regions of luminous and ultraluminous infrared galaxies. SN 2004ip is located within a circumnuclear starburst at 1.4
Douglas P. Finkbeiner, Neal Weiner
We propose a WIMP candidate with an ``excited state'' 1-2 MeV above the ground state, which may be collisionally excited and de-excites by e+e- pair emission. By converting its kinetic energy into pairs, such a particle could produce a substantial fraction of the 511 keV line observed by INTEGRAL/SPI in the inner Milky Way. Only a small fraction of t
Hye-Sung Lee, Konstantin T. Matchev, Salah Nasri
The left-handed sneutrino in the Minimal Supersymmetric Standard Model (MSSM) has been ruled out as a viable thermal dark matter candidate, due to conflicting constraints from direct detection experiments and from the measurement of the dark matter relic density. The intrinsic fine-tuning problem of the MSSM, however, motivates an extension with a new U(1)&#
M. Khodas, M. Pustilnik, A. Kamenev, L. I. Glazman
We evaluate the spectral function of interacting fermions in one dimension. Contrary to the Tomonaga-Luttinger model, our treatment accounts for the nonlinearity of the free fermion spectrum. In a striking departure from the Luttinger liquid theory, the spectrum nonlinearity restores the main feature of the Fermi liquid: a Lorentzian peak in the spectral fun
A. M. Stephens, A. G. Fowler, L. C. L. Hollenberg
Assuming an array that consists of two parallel lines of qubits and that permits only nearest neighbor interactions, we construct physical and logical circuitry to enable universal fault tolerant quantum computation under the [[7,1,3]] quantum code. A rigorous lower bound to the fault tolerant threshold for this array is determined in a number of physical se
Lenny Fukshansky
A lattice is called well-rounded if its minimal vectors span the corresponding Euclidean space. In this paper we completely describe well-rounded full-rank sublattices of ${\mathbb Z}^2$, as well as their determinant and minima sets. We show that the determinant set has positive density, deriving an explicit lower bound for it, while the minima set has densi
Well-posedness and invariant measures for HJM models with deterministic volatility and Lévy noise
math.PRCarlo Marinelli
We give sufficient conditions for existence, uniqueness and ergodicity of invariant measures for Musiela's stochastic partial differential equation with deterministic volatility and a Hilbert space valued driving Lévy noise. Conditions for the absence of arbitrage and for the existence of mild solutions are also discussed.
Felix Ploger, Saul Ramos-Sanchez, Michael Ratz, Patrick K. S. Vaudrevange
Z_NxZ_M orbifold models admit the introduction of a discrete torsion phase. We find that models with discrete torsion have an alternative description in terms of torsionless models. More specifically, discrete torsion can be 'gauged away' by changing the shifts by lattice vectors. Similarly, a large class of the so-called generalized discrete torsion
Longitudinal Polarization of Lambda and anti-Lambda Hyperons in Lepton-Nucleon Deep-Inelastic Scattering
hep-phJohn Ellis, Aram Kotzinian, Dmitry Naumov, Mikhail Sapozhnikov
We consider models for the spin transfers to $Λ$ and $\barΛ$ hyperons produced in lepton-nucleon deep-inelastic scattering. We make predictions for longitudinal $Λ$ and $\barΛ$ spin transfers for the COMPASS experiment and for HERA, and for the spin transfer to $Λ$ hyperons produced at JLAB. We demonstrate that accurate measurements of the spin transfers to
The dynamical formation of LMXBs in dense stellar environments: globular clusters and the inner bulge of M31
astro-phRasmus Voss, Marat Gilfanov
The radial distribution of luminous L_X>10^{36} erg/s X-ray point sources in the bulge of M31 is investigated using archival Chandra observations. We find a significant increase of the specific frequency of X-ray sources, per unit stellar mass, within 1 arcmin from the centre of the galaxy. The radial distribution of surplus sources in this region follows th
Jie Wang, Simon D. M. White
In Hot or Warm Dark Matter universes the density fluctuations at early times contain very little power below a characteristic wavelength related inversely to the particle mass. We study how discreteness noise influences the growth of nonlinear structures smaller than this coherence scale in N-body simulations of cosmic structure formation. It has been known
Electrical current-driven pinhole formation and insulator-metal transition in tunnel junctions
cond-mat.mtrl-sciJ. Ventura, Z. Zhang, Y. Liu, J. B. Sousa
Current Induced Resistance Switching (CIS) was recently observed in thin tunnel junctions (TJs) with ferromagnetic (FM) electrodes and attributed to electromigration of metallic atoms in nanoconstrictions in the insulating barrier. The CIS effect is here studied in TJs with two thin (20 Å) non-magnetic (NM) Ta electrodes inserted above and below the insulati
Lizhao Zhang
Given a degenerate $(n+1)$-simplex in a $d$-dimensional space $M^d$ (Euclidean, spherical or hyperbolic space, and $d\geq n$), for each $k$, $1\leq k\leq n$, Radon's theorem induces a partition of the set of $k$-faces into two subsets. We prove that if the vertices of the simplex vary smoothly in $M^d$ for $d=n$, and the volumes of $k$-faces in one subse
A. G. Lebed, Si Wu
We suggest a model to explain the appearance of a high resistance high magnetic field charge-density-wave (CDW) phase, discovered by D. Graf et al. [Phys. Rev. Lett. v. 93, 076406 (2004)] in (Per)2Pt(mnt)2. In particular, we show that the Pauli spin-splitting effects improve the nesting properties of a realistic quasi-one-dimensional electron spectrum and, t
A. Eggenberger, S. Udry, T. Mazeh, Y. Segal
The discovery of a short-period giant planet (a hot Jupiter) around the primary component of the triple star system HD 188753 has often been considered as an important observational evidence and as a serious challenge to planet-formation theories. Following this discovery, we monitored HD 188753 during one year to better characterize the planetary orbit and
Emmanuel Chasseigne
We study the Dirichlet problem for the non-local diffusion equation $u_t=\int\{u(x+z,t)-u(x,t)\}\dmu(z)$, where $μ$ is a $L^1$ function and $``u=ϕ$ on $\partialΩ\times(0,\infty)$'' has to be understood in a non-classical sense. We prove existence and uniqueness results of solutions in this setting. Moreover, we prove that our solutions coincide with
Francesco Riboli, Alessio Recati, Mauro Antezza, Iacopo Carusotto
We study the electromagnetic force exerted on a pair of parallel slab waveguides by the light propagating through them. We have calculated the dependence of the force on the slab separation by means of the Maxwell--Stress tensor formalism and we have discussed its main features for the different propagation modes: spatially symmetric (antisymmetric) modes gi
C. Bouchiat
In this paper, we have studied, within a discrete WLC model, the spatial constraints in magnetic tweezers used in single molecule experiments. Two elements are involved: first, the fixed plastic slab on which is stuck the initial strand, second, the magnetic bead which pulls (or twists) the attached molecule free end. We have shown that the bead surface can
Mariana Pereira
We study the representations of two types of pointed Hopf algebras: restricted two-parameter quantum groups, and the Drinfel'd doubles of rank one pointed Hopf algebras of nilpotent type. We study, in particular, under what conditions a simple module can be factored as the tensor product of a one dimensional module with a module that is naturally a modul
Joel Ouaknine, James Worrell
Metric Temporal Logic (MTL) is a prominent specification formalism for real-time systems. In this paper, we show that the satisfiability problem for MTL over finite timed words is decidable, with non-primitive recursive complexity. We also consider the model-checking problem for MTL: whether all words accepted by a given Alur-Dill timed automaton satisfy a g
Anton Alekseev, Samuel Monnier
We describe a non-perturbative quantization of classical Wilson loops in the WZW model. The quantized Wilson loop is an operator acting on the Hilbert space of closed strings and commuting either with the full Kac-Moody chiral algebra or with one of its subalgebras. We prove that under open/closed string duality, it is dual to a boundary perturbation of the
Sylvain E. Cappell, Julius L. Shaneson
This paper concerns the number of lattice points in a circle.
Shin Muroya
We investigate coefficients in the Israel-Stewart's causal hydrodynamics and discuss the way to calculate them with a microscopic theory. Based on the hadro-molecular simulation based on an event generator URASiMA, we evaluate the coefficients for a hot and dense hadronic fluid.
General Connectivity Distribution Functions for Growing Networks with Preferential Attachment of Fractional Power
cond-mat.stat-mechKazumoto Iguchi, Hiroaki Yamada
We study the general connectivity distribution functions for growing networks with preferential attachment of fractional power, $Π_{i} \propto k^α$, using the Simon's method. We first show that the heart of the previously known methods of the rate equations for the connectivity distribution functions is nothing but the Simon's method for word problem
Sevinc O. Tagieva, Askin Ankay, Arzu M. Ankay
The available data on isolated X-ray pulsars, their wind nebulae, and the supernova remnants which are connected to some of these sources are analyzed. It is shown that electric fields of neutron stars tear off charged particles from the surface of neutron star and trigger the acceleration of particles. The charged particles are accelerated mainly in the fie
D. M. Brink, Fl. Stancu
We present the evolution of the shell structure of nuclei in Hartree-Fock calculations using Skyrme's density-dependent effective nucleon-nucleon interaction. The role of the tensor part of the Skyrme interaction to the Hartree-Fock spin-orbit splitting in spherical spin unsaturated nuclei is reanalyzed. The contribution of a finite range tensor force to
Severin G. Jakobs, Volker Meden, Herbert Schoeller
We propose a nonequilibrium version of functional renormalization within the Keldysh formalism by introducing a complex valued flow parameter in the Fermi or Bose functions of each reservoir. Our cutoff scheme provides a unified approach to equilibrium and nonequilibrium situations. We apply it to nonequilibrium transport through an interacting quantum wire
R. Sekhar Chivukula, Shinya Matsuzaki, Elizabeth H. Simmons, Masaharu Tanabashi
In this paper we compute the one-loop chiral logarithmic corrections to all O(p^4) counterterms in the three site Higgsless model. The calculation is performed using the background field method for both the chiral- and gauge-fields, and using Landau gauge for the quantum fluctuations of the gauge fields. The results agree with our previous calculations of th
Fantappié-Arcidiacono theory of relativity versus recent cosmological evidences : a preliminary comparison
physics.gen-phLeonardo Chiatti
Notwithstanding the Fantappie-Arcidiacono theory of relativity was introduced more than half a century ago, its observational confirmations in cosmology (the only research field where its predictions differ from those of the Einsteinian relativity) are still missing. In line of principle, this theory may be proposed as a valid alternative to the current view
A. E. Gildemeister, T. Ihn, M. Sigrist, K. Ensslin
We present a detailed experimental study on the electrostatic interaction between a quantum dot and the metallic tip of a scanning force microscope. Our method allowed us to quantitatively map the tip-induced potential and to determine the spatial dependence of the tip's lever arm with high resolution. We find that two parts of the tip-induced potential
Effects of the size of cosmological N-body simulations on physical quantities II-. Halo formation and destruction rate
astro-phJayanti Prasad
In this study we show how errors due to finite box size affect formation and destruction rate for haloes in cosmological N-body simulations. In an earlier study we gave an analytic prescription of finding the corrections in the mass function. Following the same approach, in this paper we give analytical expressions for corrections in the formation rate, dest
N. Armesto, M. A. Braun, C. Pajares
Long-range correlations between multiplicities in different rapidity windows in hadron-nucleus collisions are analyzed. After recalling the standard results in the probabilistic model, we study them in the framework of perturbative QCD. Considering interacting BFKL pomerons in the form of fan diagrams coupled to a dilute projectile, analytic estimates are do
Dave Benson, Srikanth B. Iyengar, Henning Krause
We propose a new method for defining a notion of support for objects in any compactly generated triangulated category admitting small coproducts. This approach is based on a construction of local cohomology functors on triangulated categories, with respect to a central ring of operators. Suitably specialized one recovers, for example, the theory for commutat
Gerald A. Goldin, Nick E. Mavromatos, Richard J. Szabo
For a superstring theory in four spacetime dimensions, we propose a modification of the Born-Infeld action that possesses a well-defined tensionless limit. We interpret this as describing the effective target space dynamics of null strings on a D3-brane. We argue that such a modification can be induced by nonperturbative contributions from instantons in the
Group analysis and exact solutions of a class of variable coefficient nonlinear telegraph equations
math-phDing-jiang Huang, Nataliya M. Ivanova
A complete group classification of a class of variable coefficient (1+1)-dimensional telegraph equations $f(x)u_{tt}=(H(u)u_x)_x+K(u)u_x$, is given, by using a compatibility method and additional equivalence transformations. A number of new interesting nonlinear invariant models which have non-trivial invariance algebras are obtained. Furthermore, the possib
S. Banerjee, M. Mandal, N. Gayathri, M. Sardar
We report here enhancement of ferromagnetism in pure ZnO upon thermal annealing with the ferromagnetic transition temperature Tc above room temperature. We observe a finite coercive field upto 300K and a finite thermoremanent magnetization upto 340K for the annealed sample. We propose that magnetic moments can form at anionic vacancy clusters. Ferromagnetism
Maximilian G. Schultz, Tamara S. Nunner, Felix von Oppen
The vibrational modes of Jahn-Teller molecules are affected by a Berry phase that is associated with a conical intersection of the adiabatic potentials. We investigate theoretically how this Berry phase affects transport through a single $E \otimes e$ Jahn-Teller molecule when the tunneling electrons continually switch the molecule between a symmetric and a
Frequency- and transverse wave-vector-dependent spin Hall conductivity in two-dimensional electron gas with disorder
cond-mat.mes-hallSudhansu S. Mandal, Ankur Sensharma
We determine wave number $q$ and frequency $ω$ dependent spin Hall conductivity $σ_{yx}^s(q, ω)$ for a disordered two dimensional electron system with Rashba spin orbit interaction when $\q$ is {\it transverse} to the electric field. Both the conventional definition of spin current and its new definition which takes care of the conservation of spins, have be
K. Schönhammer
Recently the damping of the collective charge (and spin) modes of interacting fermions in one spatial dimension was studied. It results from the nonlinear correction to the energy dispersion in the vicinity of the Fermi points. To investigate the damping one has to replace the random phase approximation (RPA) bare bubble by a sum of more complicated diagrams
Itamar Pitowsky
Contemporary versions of Bell's argument against local hidden variable (LHV) theories are based on the Clauser Horne Shimony and Holt (CHSH) inequality, and various attempts to generalize it. The amount of violation of these inequalities cannot exceed the bound set by the Grothendieck constants. However, if we go back to the original derivation by Bell,
Jose L. Rodriguez, Jerome Scherer
Let $M$ denote a two-dimensional Moore space (so $H_2(M; \Z) = 0$), with fundamental group $G$. The $M$-cellular spaces are those one can build from $M$ by using wedges, push-outs, and telescopes (and hence all pointed homotopy colimits). The question we address here is to characterize the class of $M$-cellular spaces by means of algebraic properties derived
Dorota Sobczynska
The gamma/hadron separation in the imaging air Cherenkov telescope technique is based on differences between images of a hadronic shower and a gamma induced electromagnetic cascade. One may expect for a large telescope that a detection of hadronic events containing Cherenkov light from one gamma subcascade only is possible. In fact, simulations show that for
Eun Kyung Park, Pyung Seong Kwon
We present a new type of self-tuning mechanism for ($3+p$)d brane world models in the framework of gravity-scalar theory. This new type of self-tuning mechanism exhibits a remarkable feature. In the limit $g_s \to 0$, $g_s$ being the string coupling, the geometry of bulk spacetime remains virtually unchanged by an introduction of the Standard Model(SM)-brane
Raju Renjit. G
This submission has been withdrawn at the request of the author.
Eric Cancès, Amélie Deleurence, Mathieu Lewin
This article is concerned with the derivation and the mathematical study of a new mean-field model for the description of interacting electrons in crystals with local defects. We work with a reduced Hartree-Fock model, obtained from the usual Hartree-Fock model by neglecting the exchange term. First, we recall the definition of the self-consistent Fermi sea
Seungjoon Hyun, Wontae Kim, John J. Oh, Edwin J. Son
The entropy for two-dimensional black holes is obtained through the entropy function with the condition that the geometry approaches an $AdS_2$ spacetime in the near horizon limit. It is shown that the entropy is universal and proportional to the value of the dilaton field at the event horizon as expected. We find this universal behavior holds even after the
John A. Baldwin
Suppose that S is a surface with boundary and that g and h are diffeomorphisms of S which restrict to the identity on the boundary. Let Y_g, Y_h, and Y_{hg} be the three-manifolds with open book decompositions given by (S,g), (S,h), and (S,hg), respectively. We show that the Ozsvath-Szabo contact invariant is natural under a comultiplication map on Heegaard
Ryan C. Hickox, Maxim Markevitch
We present a measurement of the surface brightness of the cosmic X-ray background (CXB) in the Chandra Deep Fields, after excluding all detected X-ray, optical and infrared sources. The work is motivated by a recent X-ray stacking analysis by Worsley and collaborators, which showed that galaxies detected by HST but not by Chandra may account for most of the
Sergiu I. Vacaru
This is the second paper in a series of works devoted to nonholonomic Ricci flows. By imposing non-integrable (nonholonomic) constraints on the Ricci flows of Riemannian metrics we can model mutual transforms of generalized Finsler-Lagrange and Riemann geometries. We verify some assertions made in the first partner paper and develop a formal scheme in which
Macroscopic quantum tunneling and quasiparticle-tunneling blockade effect in s-wave/d-wave hybrid junctions
cond-mat.supr-conS. Kawabata, A. A. Golubov, Ariando, C. J. M. Verwijs
We have theoretically investigated macroscopic quantum tunneling (MQT) and the influence of nodal quasiparticles and zero energy bound states (ZES) on MQT in s-wave/ d-wave hybrid Josephson junctions. In contrast to d-wave/d-wave junctions, the low-energy quasiparticle dissipation resulting from nodal quasiparticles and ZES is suppressed due to a quasipartic
Andreas Raab
We discuss a general model for effective quantum field theories (QFTs), which for example comprises quantum chromodynamics and quantum electrodynamics. We assume in the model a perturbative expansion of the Lagrangian with respect to a cut-off-energy parameter. For each order in the expansion we rigorously derive a representation, which is unitarily equivale
Wojciech Wasilewski, Piotr Kolenderski, Robert Frankowski
We propose and demonstrate a method for measuring the spectral density matrix of a single photon pulse. The method is based on registering Hong-Ou-Mandel interference between photon to be measured and a pair of attenuated and suitably delayed laser pulses described by a known spectral amplitude. The density matrix is retrieved from a two-dimensional interfer
Influence of pure-dephasing by phonons on exciton-photon interfaces: Quantum microscopic theory
quant-phKunihiro Kojima, Akihisa Tomita
We have developed a full quantum microscopic theory to analyze the time evolution of transversal and longitudinal components of an exciton-single photon system coupled to bulk acoustic phonons. These components are subjected to two decay processes. One is radiative relaxation and the other is pure-dephasing due to exciton-phonon interaction. The former resul
Nathaniel Lasry
Peer Instruction (PI) is a student-centered instructional approach developed at Harvard by Eric Mazur (1997). The method has been welcomed by the science community and adopted by a large number of colleges and universities, due among other reasons to its common sense approach and its documented effectiveness. In PI, the progression of any given class depends
Yet on statistical properties of traded volume: correlation and mutual information at different value magnitudes
physics.data-anSilvio M. Duarte Queiros, Luis G. Moyano
In this article we analyse linear correlation and non-linear dependence of traded volume, $v$, of the 30 constituents of Dow Jones Industrial Average at different value scales. Specifically, we have raised $v$ to some real value $α$ or $β$, which introduces a bias for small ($ α, β<0$) or large ($α, β>1$) values. Our results show that small values of $v$ are
A study of H+H$_2$ and several H-bonded molecules by phaseless auxiliary-field quantum Monte Carlo with planewave and Gaussian basis sets
physics.comp-phW. A. Al-Saidi, Henry Krakauer, Shiwei Zhang
We present phaseless auxiliary-field (AF) quantum Monte Carlo (QMC) calculations of the ground states of some hydrogen-bonded systems. These systems were selected to test and benchmark different aspects of the new phaseless AF QMC method. They include the transition state of H+H$_2$ near the equilibrium geometry and in the van der Walls limit, as well as H$_
H. Chr. Kästli, W. Bertl, W. Erdmann, K. Gabathuler
The pixel detector is the innermost tracking device of the CMS experiment at the LHC. It is built from two independent sub devices, the pixel barrel and the end disks. The barrel consists of three concentric layers around the beam pipe with mean radii of 4.4, 7.3 and 10.2 cm. There are two end disks on each side of the interaction point at 34.5 cm and 46.5 c
S. König, Ch. Hörmann, R. Horisberger, B. Meier
For the barrel part of the CMS pixel tracker about 800 silicon pixel detector modules are required. The modules are bump bonded, assembled and tested at the Paul Scherrer Institute. This article describes the experience acquired during the assembly of the first ~200 modules.
Exploring DNA translocation through a nanopore via a multiscale Lattice-Boltzmann Molecular-Dynamics methodology
physics.bio-phSimone Melchionna, Maria Fyta, Efthimios Kaxiras, Sauro Succi
A multiscale approach is used to simulate the translocation of DNA through a nanopore. Within this scheme, the interactions of the molecule with the surrounding fluid (solvent) are explicitly taken into account. By generating polymers of various initial configurations and lengths we map the probability distibutions of the passage times of the DNA through the
E. Di Grezia, S. Esposito
A complete theoretical model describing artificial disintegration of nuclei by bombardment with alpha-particles, developed by Majorana as early as in 1930, is discussed in detail alongside the basic experimental evidences that motivated it. By following the quantum dynamics of a state resulting from the superposition of a discrete state with a continuum one,
Generation and Observation of Coherent, Long--Lived Structures in a Laser--Plasma Channel
physics.plasm-phT. V. Liseykina, F. Ceccherini, F. Cornolti, E. Yu. Echkina
In recent experiments of laser pulse interaction at relativistic intensities with a low density plasma, the proton radiography technique showed evidence of long--lived field structures generated after the self-channeling of the laser pulse. We present 2D particle-in-cell simulations of this interaction regime, where the dynamics of similar structures has bee
Niels Asger Mortensen, Simon Ejsing, Sanshui Xiao
The pronounced light-matter interactions in photonic crystals make them interesting as opto-fludic "building blocks" for lab-on-a-chip applications. We show how conducting electrolytes cause dissipation and smearing of the density-of-states, thus altering decay dynamics of excited bio-molecules dissolved in the electrolyte. Likewise, we find spatial
Akhlesh Lakhtakia, Tom G. Mackay
When a strong magnetostatic field is present, vacuum effectively appears as a linear, uniaxial, dielectric-magnetic medium for small-magnitude optical fields. The availability of the frequency-domain dyadic Green function when the magnetostatic field is spatially uniform facilitates the formulation of an integral equation for the scattering of an optical fie
I. V. Grossu, S. A. El Shamali
We present a very simple method of obtaining spectacular fractals, using a particular case of a lifting Hele-Shaw cell.
A. Majumder
The four major approximation schemes devised to study the modification of jets in dense matter are outlined. The comparisons are restricted to basic assumptions and approximations made in each case and the calculation methodology used. Emergent underlying similarities between apparently disparate methods brought about by the approximation schemes are exposed
Brijesh K Srivastava
The study of correlations and fluctuations can provide evidence for the production of the quark-gluon plasma (QGP) in relativistic heavy ion collisions. Various theories predict that the production of a QGP phase in relativistic heavy ion collisions could produce significant event-by-event correlations and fluctuations in, transverse momentum, multiplicity,
G. Roland
We present a study of the CMS trigger system in heavy-ion collisions. Concentrating on two physics channels, dimuons from decays of quarkonia and single jets, we evaluate a possible trigger strategy for Pb+Pb running that relies on event selection solely in the High-Level Trigger (HLT). The study is based on measurements of the timing performance of the offl
S. Sergeev
The subject of this paper is the consecutive procedure of discretization and quantization of two similar classical integrable systems in three-dimensional space-time: the standard three-wave equations and less known modified three-wave equations. The quantized systems in discrete space-time may be understood as the regularized integrable quantum field theori
Pavel Exner, Olaf Post
We prove an abstract criterion stating resolvent convergence in the case of operators acting in different Hilbert spaces. This result is then applied to the case of Laplacians on a family $X_\eps$ of branched quantum waveguides. Combining it with an exterior complex scaling we show, in particular, that the resonances on $X_\eps$ approximate those of the Lapl
Simon P. Eveson, Christopher J. Fewster
In a recent paper [J. Math. Phys. 47 082303 (2006)], Quantum Energy Inequalities were used to place simple geometrical bounds on the energy densities of quantum fields in Minkowskian spacetime regions. Here, we refine this analysis for massive fields, obtaining more stringent bounds which decay exponentially in the mass. At the technical level this involves
M. Harmer
We describe inverse scattering for the matrix Schroedinger operator with general selfadjoint boundary conditions at the origin using the Marchenko equation. Our approach allows the recovery of the potential as well as the boundary conditions. It is easily specialised to inverse scattering on star-shaped graphs with boundary conditions at the node.
Tobias H. Colding, William P. Minicozzi
Given a Riemannian metric on the 2-sphere, sweep the 2-sphere out by a continuous one-parameter family of closed curves starting and ending at point curves. Pull the sweepout tight by, in a continuous way, pulling each curve as tight as possible yet preserving the sweepout. We show the following useful property (see Theorem 1.9 below); cf. [CM1], [CM2], prop
Remi Leandre
We define and present an example of a deformation quantization product on a Hida space of test functions endowed with a Wick product.
Kenneth R. Driessel
We work in the space of $m$-by-$n$ real matrices with the Frobenius inner product. Consider the following Problem: Given an m-by-n real matrix A and a positive integer k, find the m-by-n matrix with rank k that is closest to A. I discuss a rank-preserving differential equation (d.e.) which solves this problem. If X(t) is a solution of this d.e., then the dis
Joseph Cima, Ian Graham, Kang-Tae Kim, Steven G. Krantz
This paper treats a holomorphic self-mapping f: Omega --> Omega of a bounded domain Omega in a separable Hilbert space H with a fixed point p. In case the domain is convex, we prove an infinite-dimensional version of the Cartan-Caratheodory-Kaup-Wu Theorem. This is basically a rigidity result in the vein of the uniqueness part of the classical Schwarz lemma.