September 2007 arXiv papers — page 22

B. Durette, L. Gamond, Sylvain Hanneton, D. Alleysson

In this experiment, we test the hypothesis of whether a 'retina-like' space variant sampling pattern can improve the efficiency of a visual prosthesis. Subjects wearing a visuo-auditory substitution system were tested for their ability to point at visual targets. The test group (space-variant sampling), performed significantly better than the control

Kazuo Iwama, Harumichi Nishimura, Rudy Raymond, Shigeru Yamashita

Since the seminal work of Paturi and Simon \cite[FOCS'84 & JCSS'86]{PS86}, the unbounded-error classical communication complexity of a Boolean function has been studied based on the arrangement of points and hyperplanes. Recently, \cite[ICALP'07]{INRY07} found that the unbounded-error {\em quantum} communication complexity in the {\em one-way com

Erasmo Recami

As it is well-known, the year 2005 has been the centenary of the "annus mirabilis" (1905) during which Albert Einstein published four fundamental papers of his. But already in 1979, for the centenary of Einstein's birth, the world celebrated his monumantal work. In Italy too, there appeared scientific books, and many semi-popularization (or popularization) a

Laurent Vila, Takashi Kimura, YoshiChika Otani

We have studied the evolution of the Spin Hall Effect in the regime where the material size responsible for the spin accumulation is either smaller or larger than the spin diffusion length. Lateral spin valve structures with Pt insertions were successfully used to measure the spin absorption efficiency as well as the spin accumulation in Pt induced through t

Tanwi Ghosh, Soumitra SenGupta

Rotating dilaton black hole solution for asymptotically anti-de Sitter spacetime are obtained in the small angular momentum limit with an appropriate combination of three Liouville-type dilaton potentials. The angular momentum, magnetic dipole moment and the gyromagnetic ratio of such a black hole are determined for arbitrary values of the dilaton-electromag

M. Bai, R. Calaga, W. Fischer, P. Oddo

Following successful experience at the BNL AGS, FNAL Tevatron, and CERN SPS, an AC Dipole will be adopted at the LHC for rapid measurements of ring optics. This paper describes some of the parameters of the AC dipole for the LHC, scaling from performance of the FNAL and BNL devices.

K. P. Nayak, K. Hakuta

We show that single-atoms can be trapped on the surface of a subwavelength-diameter silica-fiber, an optical nanofiber, without any external field, and that single photons spontaneously emitted from the atoms can be readily detected through the single guided-mode of the nanofiber. A key point of the work is our finding that atom trapping sites are created on

Haifeng Wang, L. P. Shi, B. S. Luk`yanchuk, C. J. R. Sheppard

A method is presented for generation of a subwavelength (0.43 lambda) longitudinally polarized beam, which propagates without divergence over lengths of about 4 lambda in free space. This is achieved by controlling the amplitude, phase and polarization property of the Bessel-Gaussian field on the aperture of a high numerical aperture focusing lens.

Guang-Ri Jin, Sang Wook Kim

Spin squeezing of a nonlinear interaction model with Josephson-like coupling is studied to obtain time scale of maximal squeezing. Based upon two exactly solvable cases for two and three particles, we find that the maximal-squeezing time depends on the level spacing between the ground state and its next neighbor eigenstate.

B. C. Shepler, B. H. Yang, T. J. Dhilip Kumar, P. C. Stancil

A recent modeling study of brightness ratios for CO rotational transitions in gas typical of the diffuse ISM by Liszt found the role of H collisions to be more important than previously assumed. This conclusion was based on quantum scattering calculations using the so-called WKS potential energy surface (PES) which reported a large cross section for the impo

Pengfei Lan, Peixiang Lu, Wei Cao, Xinlin Wang

A new method for efficiently generating an isolated single-cycle attosecond pulse is proposed. It is shown that the ultraviolet (UV) attosecond pulse can be utilized as a robust tool to control the dynamics of electron wave packets (EWPs). By adding a UV attosecond pulse to an infrared (IR) few-cycle pulse at a proper time, only one return of the EWP to the

Kyoung Yee Kim, Hyung Won Lee, Yun Soo Myung

We investigate the agegraphic dark energy models which were recently proposed to explain the dark energy-dominated universe. For this purpose, we calculate their equation of states and squared speeds of sound. We find that the squared speed for agegraphic dark energy is always negative. This means that the perfect fluid for agegraphic dark energy is classica

Stefano Ansoldi

We review a long-standing difficulty in some semiclassical models of vacuum and vacuum decay. Surprisingly enough these models, careless of their transparent formulation, are affected by, both, technical and conceptual issues. After proving some general results that are relevant for, both, the Euclidean and Lorentzian sectors of their dynamics, we briefly hi

Masahiro N. Machida, Kohji Tomisaka, Tomoaki Matsumoto, Shu-ichiro Inutsuka

Fragmentation and binary formation processes are studied using three-dimensional resistive MHD nested grid simulations. Starting with a Bonnor-Ebert isothermal cloud rotating in a uniform magnetic field, we calculate the cloud evolution from the molecular cloud core (n=10^4 cm^-3) to the stellar core (n \simeq 10^22 cm^-3). We calculated 147 models with diff

Eric Brewe, Vashti Sawtelle, Priscilla Pamela

Including real-time data collection technology is a common practice to upgrade physics labs, and the assumption is such technology improves student learning, yet little has been done to demonstrate the effects of technology. Specific activities have been shown to be enhanced by technology, but the effects on the class as a whole has been left unexplored. Thi

Sacha E. Kopp

The Neutrinos at the Main Injector (NuMI) facility at Fermilab began operations in late 2004. NuMI will deliver an intense muon neutrino beam of variable energy (2-20 GeV). Several aspects of the design and results from runs of the MINOS experiment are reviewed. I also discuss technique to measure directly the neutrino flux using a muon flux system at the en

Herbert G. Winful

A recent paper by G. Nimtz and A. A. Stahlhofen [arXiv:0708.0681v1] makes the following claims: (1) that the authors have observed a macroscopic violation of special relativity, (2) that they have demonstrated quantum mechanical behavior of evanescent modes on a meter-length scale, and (3) that barriers are crossed in zero time, implying superluminal (faster

David G. Barnes, Christopher J. Fluke

Most research data collections created or used by astronomers are intrinsically multi-dimensional. In contrast, all visual representations of data presented within research papers are exclusively 2-dimensional. We present a resolution of this dichotomy that uses a novel technique for embedding 3-dimensional (3-d) visualisations of astronomy data sets in elec

Rugang Ye

In this survey we review Hamilton's entropy and Perelman's entropy, and provide motivations for these concepts. Then we review recent results on the logarithmic Sobolev inequality, the Sobolev inequalities and kappa-noncollapsing estimates along the Ricci flow, including the Ricci flow with surgeries.

Sheldon Stone

I report final CLEO-c results on the purely leptonic decays of the D_s^+ -> l^+ nu, for the cases when l^+ is a mu^+ or tau^+, when it decays into pi^+ anti-nu, using 314/pb of data at 4.170 GeV. I also include preliminary results from the tau^+ -> e^+ nu anti-nu channel using 195/pb. Combining both we measure f_{D_s}= 275 +/- 10 +/- 5 MeV, and f_{D_s^+}/{f_

HARP Collaboration

In the HARP experiment the large-angle spectrometer is using a cylindrical TPC as main tracking and particle identification detector. The momentum scale of reconstructed tracks in the TPC is the most important systematic error for the majority of kinematic bins used for the HARP measurements of the double-differential production cross-section of charged pion

Eleazar Cuautle, Guy Paic

A simple afterburner including radial flow to the randomized transverse momentum obtained from event generators, Pythia and Hijing, has been implemented to calculate the $p/π$ ratios and compare them with available data. A coherent trend of qualitative agreement has been obtained in $pp$ collisions and in $Au+Au$ for various centralities. Those results indic

Gordan Zitkovic

The concept of convex compactness, weaker than the classical notion of compactness, is introduced and discussed. It is shown that a large class of convex subsets of topological vector spaces shares this property and that is can be used in lieu of compactness in a variety of cases. Specifically, we establish convex compactness for certain familiar classes of

Philip R. Jarnhus, Martin S. Sloth

We study the fourth order action of the comoving curvature perturbation in an inflationary universe in order to understand more systematically the de Sitter limit in nonlinear cosmological perturbation theory. We derive the action of the curvature perturbation to fourth order in the comoving gauge, and show that it vanishes sufficiently fast in the de Sitter

Josh Barnard

We give a diameter bound for fundamental domains for isometric actions of the fundamental group of a closed hyperbolic surface on a delta-hyperbolic space, where the bound depends on the hyperbolicity constant delta, the genus of the surface, and the injectivity radius of the action, which we assume to be strictly positive.

Yufang Xi, Edmund M. Yeh

We study a pricing game in multi-hop relay networks where nodes price their services and route their traffic selfishly and strategically. In this game, each node (1) announces pricing functions which specify the payments it demands from its respective customers depending on the amount of traffic they route to it and (2) allocates the total traffic it receive

Hajime Tsuji

In this paper, I prove a very general extension theorem for log pluricanonical systems. The main application of this extension theorem is (together with Kawamata's subadjunction theorem) to give an optimal subadjunction theorem which relates the positivities of canonical bundle of the ambient projective manifold and that of the (maximal) center of log ca

Pouyan Ghaemi, Frank Wilczek

Vortices in the simplest superconducting state of graphene contain very low energy excitations, whose existence is connected to an index theorem that applies strictly to an approximate form of the relevant Bogoliubov-deGennes equations. When Zeeman interactions are taken into account, the zero modes required by the index theorem are (slightly) displaced. Thu

Gregg Jaeger, Kevin Ann

We relate disentanglement and decoherence rates in a pair of three-level atoms subjected to multi-local and collective pure dephasing noise acting in a preferred basis. The bipartite entanglement decay rate, as bounded from above by the negativity, is found to be greater than or equal to the dephasing-decoherence rates characterized by the decay of off-diago

Ben M. Leith, S. C. Cindy Ng, David L. Wiltshire

We provide preliminary quantitative evidence that a new solution to averaging the observed inhomogeneous structure of matter in the universe [gr-qc/0702082, arxiv:0709.0732], may lead to an observationally viable cosmology without exotic dark energy. We find parameters which simultaneously satisfy three independent tests: the match to the angular scale of th

Dorin Ervin Dutkay, Palle E. T. Jorgensen

We study orthogonality relations for Fourier frequencies and complex exponentials in Hilbert spaces $L^2(μ)$ with measures $μ$ arising from iterated function systems (IFS). This includes equilibrium measures in complex dynamics. Motivated by applications, we draw parallels between analysis of fractal measures on the one hand, and the geometry of wavelets on

Jane H. MacGibbon, B. J. Carr, Don N. Page

Several authors, most notably Heckler, have claimed that the observable Hawking emission from a microscopic black hole is significantly modified by the formation of a photosphere around the black hole due to QED or QCD interactions between the emitted particles. In this paper we analyze these claims and identify a number of physical and geometrical effects w

J. Gamboa, E. I. Guendelman, F. Mendez

This paper has been withdrawn and a new version will be submitted soon

Ruth Charney, Karen Vogtmann

We study the algebraic structure of the automorphism group of a general right-angled Artin group. We show that this group is virtually torsion-free and has finite virtual cohomological dimension. This generalizes results proved by the authors and John Crisp (arXiv:math/0610980) for two-dimensional right-angled Artin groups.

Don N. Page, B. J. Carr, Jane H. MacGibbon

We discuss a variety of bremsstrahlung processes associated with charged particles emitted by evaporating black holes. We show that such particles produce a negligible number of bremsstrahlung photons from their scattering off each other, though at low frequencies inner bremsstrahlung photons dominate over the direct Hawking emission of photons. This analysi

Stephen Semmes

Sets in R^n in which every pair of elements x, y can be connected by a path in the set of length bounded by a constant multiple of the distance between x and y are considered.

Omar Kettani

This paper has been withdrawn by the author, due an error in claim 1.

Sakir Ayik

We propose a microscopic stochastic approach to improve description of nuclear dynamics beyond the mean-field approximation at low energies. It is shown that, for small amplitude fluctuations, the proposed model gives a result for the dispersion of a one-body observable that is identical to the result obtained previously through a variational approach. Furth

Nobushige Kurokawa, Hiroyuki Ochiai

Spectra of real alternating operators seem to be quite interesting from the view point of explaining the Riemann Hypothesis for various zeta functions. Unfortunately we have not sufficient experiments concerning this theme. Necessary works would be to supply new examples of spectra related to zeros and poles of zeta functions. A century ago Hilbert (1907) co

M. Orlita, C. Faugeras, G. Martinez, D. K. Maude

We report on far infrared magneto-transmission measurements on a thin graphite sample prepared by exfoliation of highly oriented pyrolytic graphite. In magnetic field, absorption lines exhibiting a blue-shift proportional to sqrtB are observed. This is a fingerprint for massless Dirac holes at the H point in bulk graphite. The Fermi velocity is found to be c

P. Martineau, R. Brandenberger

There are large classes of inflationary models, particularly popular in the context of string theory and brane world approaches to inflation, in which the ratio of linearized tensor to scalar metric fluctuations is very small. In such models, however, gravitational waves produced by scalar modes cannot be neglected. We derive the lower bound on the tensor-to

Artur Avila, Jairo Bochi, David Damanik

We consider continuous $SL(2,\mathbb{R})$-cocycles over a strictly ergodic homeomorphism which fibers over an almost periodic dynamical system (generalized skew-shifts). We prove that any cocycle which is not uniformly hyperbolic can be approximated by one which is conjugate to an $SO(2,\mathbb{R})$-cocycle. Using this, we show that if a cocycle's homotopy c

Damien A. Easson, Ruth Gregory, David F. Mota, Gianmassimo Tasinato

We study the cosmological implications of including angular motion in the DBI brane inflation scenario. The non-canonical kinetic terms of the Dirac-Born-Infeld action give an interesting alternative to slow roll inflation, and cycling branes can drive periods of accelerated expansion in the Universe. We present explicit numerical solutions demonstrating bra

Paul Benioff

A quantum theory representations of real (R) and complex (C) numbers is given that is based on states of single, finite strings of qukits for any base k > 1. Both unary representations and the possibility that qukits with k a prime number are elementary and the rest composite are discussed. Cauchy sequences of qukit string states are defined from the arithme

G. Orso

We investigate the ground state properties of a disordered superfluid Fermi gas across the BCS-BEC (Bose Einstein condensate) crossover. We show that, for weak disorder, both the depletion of the condensate fraction of pairs and the normal fluid density exhibit a nonmonotonic behavior as a function of the interaction parameter $1/k_Fa$, reaching their minimu

Julia Brettschneider

The notion of a surface-order specific entropy h_c(P) of a two-dimensional discrete random field P along a curve c is introduced as the limit of rescaled entropies along lattice approximations of the blowups of c. Existence is shown by proving a corresponding Shannon-McMillan theorem. We obtain a representation of h_c(P) as a mixture of specific entropies al

Alexander A. Govyadinov, Vadim A. Markel

We consider propagation of surface plasmon polaritons (SPPs) in linear periodic chains (LPCs) of prolate and oblate metallic spheroids. We show that the SPP group velocity can be efficiently controlled by varying the aspect ratio of the spheroids. For sufficiently small aspect ratios, a gap appears in the first Brillouin zone of the chain lattice in which pr

Massimiliano Rinaldi

We consider the Green's functions associated to a scalar field propagating on a curved, ultra-static background, in the presence of modified dispersion relations. The usual proper-time deWitt-Schwinger procedure to obtain a series representation of the Green's functions is doomed to failure, because of higher order spatial derivatives in the Klein-Go

K. Beloy, A. Derevianko, W. R. Johnson

Measuring the hyperfine structure (HFS) of long-lived $^3P_2$ states of divalent atoms may offer the opportunity of extracting relatively unexplored nuclear magnetic octupole and electric hexadecapole moments. Here, using relativistic many-body methods of atomic structure and the nuclear shell model, we evaluate the effect of these higher nuclear moments on

Roberto B. Diener, Rajdeep Sensarma, Mohit Randeria

We determine the effects of quantum fluctuations about the T=0 mean field solution of the BCS-BEC crossover in a dilute Fermi gas using the functional integral method. These fluctuations are described in terms of the zero point motion of collective modes and the virtual scattering of gapped quasiparticles. We calculate their effects on various measurable pro

D. Guidetti, M. Murgia, F. Govoni, P. Parma

The goal of this work is to put constraints on the strength and structure of the magnetic field in the cluster of galaxies A2382. We investigate the relationship between magnetic field and Faraday rotation effects in the cluster, using numerical simulations as a reference for the observed polarization properties. For this purpose we present Very Large Array

David Amitrano

The deformation of rocks is associated with microcracks nucleation and propagation, i.e. damage. The accumulation of damage and its spatial localization lead to the creation of a macroscale discontinuity, so-called "fault" in geological terms, and to the failure of the material, i.e. a dramatic decrease of the mechanical properties as strength and mo

Sven Dorosz, Thierry Platini, Dragi Karevski

We study the work fluctuations of two types of finite quantum spin chains under the application of a time-dependent magnetic field in the context of the fluctuation relation and Jarzynski equality. The two types of quantum chains correspond to the integrable Ising quantum chain and the nonintegrable XX quantum chain in a longitudinal magnetic field. For seve

Li Han, Yong Guo

We show in this comment that the results obtained in a recent work by Yi et al. [Phys. Rev. Lett. 92, 150406 (2004)] are quantitatively not correct and the proposed subsystem Berry phase is not well-defined.

Naceur Gaaloul, Laurence Pruvost, Mourad Telmini, Eric Charron

We present a detailed, realistic proposal and analysis of the implementation of a cold atom deflector using time-dependent far off-resonance optical guides. An analytical model and numerical simulations are used to illustrate its characteristics when applied to both non-degenerate atomic ensembles and to Bose-Einstein condensates. Using for all relevant para

N. Cherroret, S. E. Skipetrov, B. A. Van Tiggelen

We emphasize the importance of the position dependence of the diffusion coefficient D(r) in the self-consistent theory of localization and argue that the scaling law T ~ ln(L)/L^2 obtained by Cheung and Zhang [Phys. Rev. B 72, 235102 (2005)] for the average transmission coefficient T of a disordered slab of thickness L at the localization transition is an ar

Michel Planat, Anne-Céline Baboin

The $d^2$ Pauli operators attached to a composite qudit in dimension $d$ may be mapped to the vectors of the symplectic module $\mathcal{Z}_d^{2}$ ($\mathcal{Z}_d$ the modular ring). As a result, perpendicular vectors correspond to commuting operators, a free cyclic submodule to a maximal commuting set, and disjoint such sets to mutually unbiased bases. For

Pietro Caputo, Fabio Martinelli, Fabio Lucio Toninelli

We consider paths of a one-dimensional simple random walk conditioned to come back to the origin after L steps (L an even integer). In the 'pinning model' each path ηhas a weight λ^{N(η)}, where λ>0 and N(η) is the number of zeros in η. When the paths are constrained to be non-negative, the polymer is said to satisfy a hard-wall constraint. Such mode

A. Li Bassi, C. S. Casari, D. Cattaneo, F. Donati

A simple, reliable method for preparation of bulk Cr tips for Scanning Tunneling Microscopy (STM) is proposed and its potentialities in performing high-quality and high-resolution STM and Spin Polarized-STM (SP-STM) are investigated. Cr tips show atomic resolution on ordered surfaces. Contrary to what happens with conventional W tips, rest atoms of the Si(11

Marco Ruggieri

I discuss briefly the instabilities of two flavor quark matter, paying attention to the gradient instability which develops in the g2SC phase in the Goldstone $U(1)_A$ sector.

S. Kessler, R. Finken, U. Seifert

The deformation of an elastic micro-capsule in an infinite shear flow is studied numerically using a spectral method. The shape of the capsule and the hydrodynamic flow field are expanded into smooth basis functions. Analytic expressions for the derivative of the basis functions permit the evaluation of elastic and hydrodynamic stresses and bending forces at

Andrea Altomani, Costantino Medori, Mauro Nacinovich

We compute the Euler-Poincaré characteristic of the homogeneous compact manifolds that can be described as minimal orbits for the action of a real form in a complex flag manifold.

S. Verley, L. K. Hunt, E. Corbelli, C. Giovanardi

Combining the relative vicinity of the Local Group spiral galaxy M33 with the Spitzer images, we investigate the properties of infrared (IR) emission sites and assess the reliability of the IR emission as a star formation tracer. The mid- and far-IR emission of M33 was obtained from IRAC and MIPS images from the Spitzer archive. We compared the photometric r

Julia Brettschneider

Consider a class of skew product transformations consisting of an ergodic or a periodic transformation on a probability space (M, B, m) in the base and a semigroup of transformations on another probability space (W,F,P) in the fibre. Under suitable mixing conditions for the fibre transformation, we show that the properties ergodicity, weakly mixing, and stro

Kumar Rao, Saurabh D. Rindani

We examine very general four-point interactions arising from new physics and contributing to the Higgs production process e+e- -> HZ. We write all possible forms for these interactions consistent with Lorentz invariance. We allow the possibility of CP violation. Contributions to the process from anomalous ZZH and gamma ZH interactions studied earlier arise a

C. Faugeras, A. Nerriere, M. Potemski, A. Mahmood

The results of micro-Raman scattering measurements performed on three different ``graphitic'' materials: micro-structured disks of highly oriented pyrolytic graphite, graphene multi-layers thermally decomposed from carbon terminated surface of 4H-SiC and an exfoliated graphene monolayer are presented. Despite its multi-layer character, most parts of

Yoichi Motohashi

This is a rework of our old file, which has been left unpublished since September 1994, on an explicit spectral decomposition of the fourth power moment of the Riemann zeta-function against a weight which is the square of a Dirichlet polynomial. At this occasion we add an explicit treatment of generalized Kloosterman sums associated with arbitrary Hecke cong

M. A. Hernandez Cifre, A. Schuermann, F. Vallentin

In this paper, the isodiametric problem for centrally symmetric convex bodies in the Euclidean d-space R^d containing no interior non-zero point of a lattice L is studied. It is shown that the intersection of a suitable ball with the Dirichlet-Voronoi cell of 2L is extremal, i.e., it has minimum diameter among all bodies with the same volume. It is conjectur

V. V. Mkhitaryan, A. G. Sedrakyan

We develop a simple technique for calculation of next to nearest neighbor spin-spin and chiral-spin correlation functions in inhomogeneous XXX model. Exact expression of the chiral-spin order parameter as a function of the model parameter, $ω$, is analytically found. Using the same method we also calculate the next to nearest neighbor spin-spin correlation f

Alexis Tchoudjem

Let $X$ be a complete symmetric variety i.e. the wonderful compactification of a symmetric $G-$homogeneous space (where $G$ is a simply-connected semi-simple linear algebraic group). If $L$ is a line bundle over $X$ and if $C$ is a Bialynicki-Birula cell of codimension $c$ in $X$, then the Lie algebra $\mathfrak g$ of $G$ operates naturally on the cohomology

Suratna Das, Subhendra Mohanty, Kumar Rao

Unparticle exchange gives rise to long range forces which deviate from the inverse square law due to non-canonical dimension of unparticles. It is well known that a potential of the form $r^{-n}$ where $n$ is not equal to one gives rise to a precession in the perihelion of planetary orbits. We calculate the constraints on unparticle couplings with baryons an

Aurélien Manchon, Stefania Pizzini, Jan Vogel, Vojteh Uhlir

X-ray spectroscopy measurements have been performed on a series of Pt/Co/AlOx trilayers to investigate the role of Co oxidation in the perpendicular magnetic anisotropy of the Co/AlOx interface. It is observed that high temperature annealing modifies the magnetic properties of the Co layer, inducing an enhancement of the perpendicular magnetic anisotropy. Th

Yukito Iba, Koji Hukushima

The idea of rare event sampling is applied to the estimation of the performance of error-correcting codes. The essence of the idea is importance sampling of the pattern of noises in the channel by Multicanonical Monte Carlo, which enables efficient estimation of tails of the distribution of bit error rate. The idea is successfully tested with a convolutional

Elizabeth Gasparim, Thomas Köppe, Pushan Majumdar

We study the local holomorphic Euler characteristic $χ(x,\mathcal{F})$ of sheaves near a surface singularity obtained from contracting a line $\ell$ inside a smooth surface $Z$. We prove non-existence of sheaves with certain prescribed numerical invariants. Non-existence of instantons on $Z$ with certain charges follows, and we conclude that $\ell^2$ poses a

Pavel V. Avramov, Pavel B. Sorokin, Alexander S. Fedorov, Dmitri G. Fedorov

The atomic and electronic structure of a set of pristine single wall SiC nanotubes as well as Si-substituted carbon nanotubes and a SiC sheet was studied by the LDA plane wave band structure calculations. Consecutive substitution of carbon atoms by Si leads to a gap opening in the energetic spectrum of the metallic (8,8) SWCNT with approximately quadratic de

C. Z. Yuan, Belle Collaboration

The process e+e- to K+K-J/psi is observed for the first time via initial state radiation. The cross section of e+e- to K+K-J/psi for center-of-mass energies between threshold and 6.0 GeV is measured using 673 fb^{-1} of data collected with the Belle detector on and off the Upsilon(4S) resonance. We also find evidence for e+e- to K_S K_S J/psi in the same ene

Mordehai Milgrom, Robert H. Sanders

MOND predicts that a mass, M, contained within its transition radius r_t=(MG/a0)^{1/2}, may exhibit a feature at about that radius in the form of a shell, or projected ring, in the deduced distribution of its phantom dark matter. This occurs despite the absence of any underlying feature in the true (``baryon'') source distribution itself. The phenome

Shahram Khosravi, Ehsan Kourkchi, Reza Mansouri

We study the volume averaging of inhomogeneous metrics within GR and discuss its shortcomings such as gauge dependence, singular behavior as a result of caustics, and causality violations. To remedy these shortcomings, we suggest some modifications to this method. As a case study we focus on the inhomogeneous structured FRW model based on a flat LTB metric.

A. Bermudez, M. A. Martin-Delgado, A. Luis

We study the non-relativistic limit of a paradigmatic model in Relativistic Quantum Mechanics, the two-dimensional Dirac oscillator. Remarkably, we find a novel kind of Zitterbewegung which persists in this non-relativistic regime, and leads to an observable deformation of the particle orbit. This effect can be interpreted in terms of a Ramsey Interferometri

Teruaki Suyama, Masahide Yamaguchi

We investigate the non-Gaussianity of primordial curvature perturbation in the modulated reheating scenario where the primordial perturbation is generated due to the spacial fluctuation of the inflaton decay rate to radiation. We use the $δN$ formalism to evaluate the trispectrum of curvature perturbation as well as its bispectrum. We give expressions for th

Leonid Marochnik, Daniel Usikov, Grigory Vereshkov

Intrinsic properties of the space itself and quantum fluctuations of its geometry are sufficient to provide a mechanism for the acceleration of cosmological expansion (dark energy effect). Applying Bogoliubov-Born-Green-Kirkwood-Yvon hierarchy approach to self-consistent equations of one-loop quantum gravity, we found exact solutions that yield acceleration.

Andreea Picu, Antoine Fraboulet, Eric Fleury

Wireless Sensor Networks research and demand are now in full expansion, since people came to understand these are the key to a large number of issues in industry, commerce, home automation, healthcare, agriculture and environment, monitoring, public safety etc. One of the most challenging research problems in sensor networks research is power awareness and p

K. Nilsson, M. Pasanen, L. O. Takalo, E. Lindfors

We have derived R-band host galaxy fluxes of 20 TeV candidate BL Lacertae objects as a function of aperture radius and FWHM. The results are given as correction tables, that list the fluxes (in mJy) of all ``contaminating'' sources (host galaxy + significant nearby objects) as a function of aperture radius and FWHM. We found that the derived fluxes d

Paul Heideman, Emilie Hogan

We exhibit a three parameter infinite family of quadratic recurrence relations inspired by the well known Somos sequences. For one infinite subfamily we prove that the recurrence generates an infinite sequence of integers by showing that the same sequence is generated by a linear recurrence (with suitable initial conditions). We also give conjectured relatio

Sudeshna Chattopadhyay, A. Datta, A. Giglia, N. Mahne

Vacuum ultraviolet (VUV) transmission spectra show a clear polarization effect in pi electronic transition in spin coated atactic polystyrene (aPS) films of thickness below 4Rg, where Rg (~20.4nm) is the radius of gyration of the polymer. This transition associated with pendant benzene rings in polystyrene. The polarization effect clearly indicates pendant b

Jesse Gilbert

We show that for all graphs H of size n, the complete graph $K_{2n+1}$ has an $H$-decomposition.

Naseer Ahmed, Muhammad Usman

Based on the d'Alembert-Lagrange-Poincaré variational principle, we formulate general equations of motion for mechanical systems subject to nonlinear nonholonomic constraints, that do not involve Lagrangian undetermined multipliers. We write these equations in a canonical form called the Poincaré-Hamilton equations, and study a version of corresponding P

C. -A. Faucher-Giguere, J. X. Prochaska, A. Lidz, L. Hernquist

We directly measure the evolution of the intergalactic Lya effective optical depth, tau_eff, over the redshift range 2<z<4.2 from a sample of 86 high-resolution, high-signal-to-noise quasar spectra obtained with the ESI and HIRES spectrographs on Keck, and with the MIKE spectrograph on Magellan. This represents an improvement over previous analyses of the Ly

D. J. Sand, D. Zaritsky, S. Herbert-Fort, S. Sivanandam

We have begun a program to search for supernovae and other transients in the fields of galaxy clusters with the 2.3m Bok Telescope on Kitt Peak. We present our automated photometric methods for data reduction, efficiency characterization, and initial spectroscopy. With this program, we aim to ultimately identify $\sim$25-35 cluster SN Ia ($\sim$10 of which w

Tanya Urrutia, Mark Lacy, Robert H. Becker

We present Hubble ACS images of thirteen dust reddened Type-1 quasars selected from the FIRST/2MASS Red Quasar Survey. These quasars have high intrinsic luminosities after correction for dust obscuration (-23.5 > M_B > -26.2 from K-magnitude). The images show strong evidence of recent or ongoing interaction in eleven of the thirteen cases, even before the qu

Pierre-Alain Duc, Jonathan Braine, Ute Lisenfeld, Elias Brinks

Numerical simulations predict the existence of old Tidal Dwarf Galaxies (TDGs) that would have survived several Gyr after the collision lying at their origin. Such survivors, which would by now have become independent relaxed galaxies, would be ideal laboratories, if nearby enough, to tackle a number of topical issues, including the distribution of Dark Matt

Mark J. Bowick, Luca Giomi, Homin Shin, Creighton K. Thomas

We investigate crystalline order on a two-dimensional paraboloid of revolution by assembling a single layer of millimeter-sized soap bubbles on the surface of a rotating liquid, thus extending the classic work of Bragg and Nye on planar soap bubble rafts. Topological constraints require crystalline configurations to contain a certain minimum number of topolo

Z. Ditzian

About twenty years ago the measure of smoothness $ω^r_ϕ(f,t)$ was introduced and related to the rate of polynomial approximation. In this article we survey developments about this and related concepts since that time.

Joshua Pepper, K. Z. Stanek, Richard W. Pogge, David W. Latham

The Kilodegree Extremely Little Telescope (KELT) project is a small aperture, wide-angle search for planetary transits of solar-type stars. In this paper, we present the results of a commissioning campaign with the KELT telescope to observe the open cluster Praesepe for 34 nights in early 2005. Lightcurves were obtained for 69,337 stars, out of which we iden

Carl M. Bender, Joshua Feinberg

The Riemann equation $u_t+uu_x=0$, which describes a one-dimensional accelerationless perfect fluid, possesses solutions that typically develop shocks in a finite time. This equation is $\cP\cT$ symmetric. A one-parameter $\cP\cT$-invariant complex deformation of this equation, $u_t-iu(iu_x)^ε= 0$ ($ε$ real), is solved exactly using the method of characteris

Dionisios Margetis, Russel E. Caflisch

Starting from a detailed model for the kinetics of a step edge or island boundary, we derive a Gibbs-Thomson type formula and the associated step stiffness as a function of the step edge orientation angle, $theta$. Basic ingredients of the model are: (i) the diffusion of point defects (``adatoms&#39;&#39;) on terraces and along step edges; (ii) the convectio

Peter M Frinchaboy, Danielle Nielsen

The WIYN open cluster study (WOCS) has been working to yield precise magnitudes in the Johnson-Kron-Cousins UBVRI system for all stars in the field of a selection of ``prototypical&#39;&#39; open clusters. Additionally, WOCS is using radial velocities to obtain orbit solutions for all cluster binary stars with periods of less than 1000 days. Recently, WOCS i

Tsz Ho Chan

An almost square of type 2 is an integer $n$ that can be factored in two different ways as $n = a_1 b_1 = a_2 b_2$ with $a_1$, $a_2$, $b_1$, $b_2 \approx \sqrt{n}$. In this paper, we shall improve upon previous result on short intervals containing an almost square of type 2. This leads to an inquiry of finding a short interval around $x$ that contains an int

Mathieu Stienon

An equivariant bundle gerbe à la Meinrenken over a $G$-manifold $M$ is known to be a special type of $S^1$-gerbe over the differentiable stack $[M/G]$. We prove that the natural morphism relating the Cartan and simplicial models of equivariant cohomology in degree 3 maps the Dixmier-Douady class of an equivariant bundle gerbe à la Meinrenken to the Behrend-X

J. Hong, J. E. Grindlay, N. Chammas, B. Allen

We report our progress on the development of pixellated imaging CZT detector arrays for our first-generation balloon-borne wide-field hard X-ray (20 - 600 keV) telescope, ProtoEXIST1. Our ProtoEXIST program is a pathfinder for the High Energy Telescope (HET) on the Energetic X-ray Imaging Survey telescope (EXIST), a proposed implementation of the Black Hole