June 2007 arXiv papers — page 35

Agnieszka B. Malinowska, Delfim F. M. Torres

The question of obtaining well-defined criteria for multiple criteria decision making problems is well-known. One of the approaches dealing with this question is the concept of nonessential objective function. A certain objective function is called nonessential if the set of efficient solutions is the same both with or without that objective function. In thi

A. S. Cohen, W. M. Lane, W. D. Cotton, N. E. Kassim

The Very Large Array (VLA) Low-frequency Sky Survey (VLSS) has imaged 95% of the 3*pi sr of sky north of declination = -30 degrees at a frequency of 74 MHz (4 meter wavelength). The resolution is 80" (FWHM) throughout, and the typical RMS noise level is ~0.1 Jy/beam. The typical point-source detection limit is 0.7 Jy/beam and so far nearly 70,000 sources

Martin Goldstern, Saharon Shelah

Let kappa be an uncountable regular cardinal. Assuming 2^kappa=kappa^+, we show that the clone lattice on a set of size kappa is not dually atomic.

Ling Bao, Martin Cederwall, Bengt E. W. Nilsson

We discuss various aspects of dimensional reduction of gravity with the Einstein-Hilbert action supplemented by a lowest order deformation formed as the Riemann tensor raised to powers two, three or four. In the case of R^2 we give an explicit expression, and discuss the possibility of extended coset symmetries, especially SL(n+1,Z) for reduction on an n-tor

E. M. Waldram, R. C. Bolton, G. G. Pooley, J. M. Riley

We have used multi-frequency follow-up observations of a sample of extragalactic sources from the 9C survey at 15 GHz to make deductions about the expected source population at higher radio frequencies, such as those in the lower frequency bands of the Planck Surveyor satellite. In particular, we have made empirical estimates of the source counts at 22 GHz,

Saverio Bivona, Giovanni Bonanno, Riccardo Burlon, Claudio Leone

The effect of an intense external linear polarized radiation field on the angular distributions and polarization states of the photons emitted during the radiative recombination is investigated. It is predicted, on symmetry grounds, and corroborated by numerical calculations of approximate recombination rates, that emission of elliptically polarized photons

Hichem Geryville, Abdelaziz Bouras, Yacine Ouzrout, Nikolaos Sapidis

The design and development of complex products invariably involves many actors who have different points of view on the problem they are addressing, the product being developed, and the process by which it is being developed. The actors' viewpoints approach was designed to provide an organisational framework in which these different perspectives or point

Hans C. Fogedby

Stochastic Loewner evolution also called Schramm Loewner evolution (abbreviated, SLE) is a rigorous tool in mathematics and statistical physics for generating and studying scale invariant or fractal random curves in two dimensions. The method is based on the older deterministic Loewner evolution introduced by Karl Loewner, who demonstrated that an arbitrary

A. N. Samukhin, S. N. Dorogovtsev, J. F. F. Mendes

We study the Laplacian operator of an uncorrelated random network and, as an application, consider hopping processes (diffusion, random walks, signal propagation, etc.) on networks. We develop a strict approach to these problems. We derive an exact closed set of integral equations, which provide the averages of the Laplacian operator's resolvent. This en

A. D. Neate, A. Truman

The inviscid limit of the stochastic Burgers equation, with body forces white noise in time, is discussed in terms of the level surfaces of the minimising Hamilton-Jacobi function, the classical mechanical caustic and the Maxwell set and their algebraic pre-images under the classical mechanical flow map. The problem is analysed in terms of a reduced (one dim

J. Gaertner, F. den Hollander, G. Maillard

The present paper provides an overview of results obtained in four recent papers by the authors. These papers address the problem of intermittency for the Parabolic Anderson Model in a \emph{time-dependent random medium}, describing the evolution of a ``reactant'' in the presence of a ``catalyst''. Three examples of catalysts are considered:

Ralf R. Mueller, Dongning Guo, Aris L. Moustakas

We apply the replica method to analyze vector precoding, a method to reduce transmit power in antenna array communications. The analysis applies to a very general class of channel matrices. The statistics of the channel matrix enter the transmitted energy per symbol via its R-transform. We find that vector precoding performs much better for complex than for

Yoshihiro Ueda, Satoshi Eguchi, Yuichi Terashima, Richard Mushotzky

We present the Suzaku broad band observations of two AGNs detected by the Swift/BAT hard X-ray (>15 keV) survey that did not have previous X-ray data, Swift J0601.9-8636 and Swift J0138.6-4001. The Suzaku spectra reveals in both objects a heavily absorbed power law component with a column density of NH =~ 10^{23.5-24} cm^{-2} that dominates above 10 keV, and

Niall O Murchadha

A quasi-local mass has been a long sought after quantity in general relativity. A recent candidate has been the Liu-Yau mass. One can show that the Liu-Yau mass of any two-surface is the maximum of the Brown-York energy for that two-surface. This means that it has significant disadvantages as a mass. It is much better interpreted as an energy and I will show

Francois Rincon

The problem of two-dimensional steady nonlinear dynamics in plane Couette flow is revisited using homotopy from either plane Poiseuille flow or from plane Couette flow perturbed by a small symmetry-preserving identity operator. Our results show that it is not possible to obtain the nonlinear plane Couette flow solutions reported by Cherhabili and Ehrenstein

R. F. Mamin, I. K. Bdikin, A. L. Kholkin

We report the direct evidence of the possibility of charge segregation in manganites. The high contrast of electric-field-induced local charged states is observed during more than 100 hours at room temperature. These induced states display a piezoelectric response and polar properties. This effect may be an example of a new kind of polar ordering in solid st

Hichem Geryville, Yacine Ouzrout, Abdelaziz Bouras, Nikolaos Sapidis

Nowadays, to achieve competitive advantage, the industrial companies are considering that success is sustained to great product development. That is to manage the product throughout its entire lifecycle. Achieving this goal requires a tight collaboration between actors from a wide variety of domains, using different software tools producing various product d

Mohammed Debbarh

We establish some uniform limit results in the setting of additive regression model estimation. Our results allow to give an asymptotic 100% confidence bands for these components. These results are stated in the framework of i.i.d random vectors when the marginal integration estimation method is used.

Oscar Sotolongo-Costa, R. Gamez, A. Posadas, F. Luzon

The classification of earthquakes in main shocks and aftershocks by a method recently proposed by M. Baiesi and M. Paczuski allows to the generation of a complex network composed of clusters that group the most correlated events. The spatial distribution of epicentres inside these structures corresponding to the catalogue of earthquakes in the eastern region

A. D. Neate, A. Truman

The inviscid limit of the stochastic Burgers equation is discussed in terms of the level surfaces of the minimising Hamilton-Jacobi function, the classical mechanical caustic and the Maxwell set and their algebraic pre-images under the classical mechanical flow map. The problem is analysed in terms of a reduced (one dimensional) action function. We demonstra

M. M. Zemljic, P. Prelovsek, T. Tohyama

It is shown that spectral functions within the extended t-J model, evaluated using the finite-temperature diagonalization of small clusters, exhibit the high-energy kink in single-particle dispersion consistent with recent angle-resolved photoemission results on hole-doped cuprates. The kink and waterfall-like features persist up to large doping and to tempe

Svitlana Zhukovska, Hans-Peter Gail, Mario Trieloff

The abundance evolution of interstellar dust species originating from stellar sources and from condensation in molecular clouds in the local interstellar medium of the Milky Way is studied and the input of dust material to the Solar System is determined. A one-zone chemical evolution model of the Milky Way for the elemental composition of the disk combined w

Mohammed Debbarh, Bertrand Maillot

In the setting of additive regression model for continuous time process, we establish the optimal uniform convergence rates and optimal asymptotic quadratic error of additive regression. To build our estimate, we use the marginal integration method.

B. S. Gonzalez, J. Hernandez-Rojas, J. Breton, J. M. Gomez Llorente

Likely candidates for the global potential energy minima of (H$_{2}$O)$_{n}$ clusters with $n\leq21$ on the (0001)-surface of graphite are found using basin-hopping global optimization. The potential energy surfaces are constructed using the TIP4P intermolecular potentials for the water molecules (the TIP3P is also explored as a secondary choice), a Lennard-

Matthias R. Brust, Steffen Rothkugel

Topology Control (TC) aims at tuning the topology of highly dynamic networks to provide better control over network resources and to increase the efficiency of communication. Recently, many TC protocols have been proposed. The protocols are designed for preserving connectivity, minimizing energy consumption, maximizing the overall network coverage or network

C. S. Kim, Sechul Oh, Chandradew Sharma, Rahul Sinha

We study $B \to K^* ρ$ modes that are analogues of the much studied $B\to K π$ modes with B decaying to two vector mesons instead of pseudoscalar mesons, using topological amplitudes in the quark diagram approach. We show how $B \to K^*ρ$ modes can be used to obtain many more observables than those for $B \to K π$ modes, even though the quark level subproces

M. K. Argo, A. Pedlar, R. J. Beswick, T. W. B. Muxlow

A study of the distribution of OH gas in the central region of the nearby active starburst galaxy M82 has confirmed two previously known bright masers and revealed several new main line masers. Three of these are seen only at 1665 MHz, one is detected only at 1667 MHz, while the rest are detected in both lines. Observations covering both the 1665 and 1667 MH

P. Machnikowski

This Chapter contains a review of the recent results, both experimental and theoretical, related to optical control of carriers confined in semiconductor quantum dots. The physics of Rabi oscillations of exciton and biexciton occupations, as well as time-domain interference experiments are discussed. Next, the impact of carrier--phonon interaction in a semic

R. Gurau, A. Tanasa

Using the recently introduced parametric representation of non-commutative quantum field theory, we implement here the dimensional regularization and renormalization of the vulcanized $Φ^{\star 4}_4$ model on the Moyal space.

A. Monreal-Ibero, L. Colina, S. Arribas, M. Garcia-Marin

(ABRIDGED) Star-forming small galaxies made out of collisional debris have been found in a variety of merging systems. So far only a few of them are known in ULIRGs although they show clear signs of interactions. Whether external star formation may take place in such objects is an open question. The aim of this paper is to identify and characterise the physi

Matthias R. Brust, Steffen Rothkugel

Ad-hoc networks, a promising trend in wireless technology, fail to work properly in a global setting. In most cases, self-organization and cost-free local communication cannot compensate the need for being connected, gathering urgent information just-in-time. Equipping mobile devices additionally with GSM or UMTS adapters in order to communicate with arbitra

Adrian Andronache, Matthias R. Brust, Steffen Rothkugel

Fixed infrastructured networks naturally support centralized approaches for group management and information provisioning. Contrary to infrastructured networks, in multi-hop ad-hoc networks each node acts as a router as well as sender and receiver. Some applications, however, requires hierarchical arrangements that-for practical reasons-has to be done locall

F. De Luise, D. Perna, E. Dotto, S. Fornasier

In this paper we present the observational campaign carried out at ESO NTT and VLT in April and May 2006 to investigate the nature and the structure of the Near Earth Object (144898) 2004 VD17. In spite of a great quantity of dynamical information, according to which it will have a close approach with the Earth in the next century, the physical properties of

A. Perez, A. Romanelli

We present two new continuous time quantum search algorithms similar to the adiabatic search algorithm, but now without an adiabatic evolution. We find that both algorithms work for a wide range of values of the parameters of the Hamiltonian, and one of them has, as an additional feature that, for values of time larger than a characteristic one, it will conv

Amanda Bouffier, Thierry Poibeau

This paper describes a system capable of semi-automatically filling an XML template from free texts in the clinical domain (practice guidelines). The XML template includes semantic information not explicitly encoded in the text (pairs of conditions and actions/recommendations). Therefore, there is a need to compute the exact scope of conditions over text seq

Patrick Van Esch

We propose an analysis of the dead time losses in counting imaging detectors such as MWPC which can resolve $k$ simultaneous hits, and analyze in more detail an $X-Y$ detector which has a third wire set which allows for the recognition of simultaneous impacts.

A. Imparato, L. Peliti

We argue that the apparent failure of the work-Hamiltonian connection for free energy calculations reported by Vilar and Rubi' (cond-mat arXiv:0704.0761v2) stems from their incorrect expression for the work.

M. Arnould, M. Katsuma

A necessary condition for the reliable modelling of the structure or evolution of the stars and of their concomitant nucleosynthesis is the availability of good quality nuclear data in a very wide area of the chart of nuclides. This short review presents a non-exhaustive list of nuclear data of astrophysics interest (masses, $β$-decays, thermonuclear and non

Matthias R. Brust, Steffen Rothkugel

Mobile entities with wireless links are able to form a mobile ad-hoc network. Such an infrastructureless network does not have to be administrated. However, self-organizing principles have to be applied to deal with upcoming problems, e.g. information dissemination. These kinds of problems are not easy to tackle, requiring complex algorithms. Moreover, the u

D. C. Hannikainen, M. G. Rawlings, P. Muhli, O. Vilhu

The INTEGRAL observatory has been (re-)discovering new X-ray sources since the beginning of nominal operations in early 2003. These sources include X-ray binaries, Active Galactic Nuclei, cataclysmic variables, etc. Amongst the X-ray binaries, the true nature of many of these sources has remained largely elusive, though they seem to make up a population of h

Matthias R. Brust, Christian M. Adriano, Ivan M. L. Ricarte

In the field of evaluation research, computer scientists live constantly upon dilemmas and conflicting theories. As evaluation is differently perceived and modeled among educational areas, it is not difficult to become trapped in dilemmas, which reflects an epistemological weakness. Additionally, designing and developing a computer-based learning scenario is

M. Einasto, E. Saar, J. Einasto, E. Tago

We study the morphology of galaxy populations of the richest superclusters from the catalogue of superclusters of galaxies in the 2dF Galaxy Redshift Survey using the luminosity density distribution and Minkowski functional V3. We compare the properties of grouped and isolated galaxies in regions of different density in superclusters. We find that in high-de

C. Adamuščín, G. I. Gakh, E. Tomasi-Gustafsson

The electron positron annihilation reaction into four pion production has been studied, through the channel $e^++e^-\to \bar ρ+ρ$. The differential (and total) cross sections and various polarization observables for this reaction have been calculated in terms of the electromagnetic form factors of the corresponding $γ^*ρρ$ current. The elements of the spin--

M. Einasto, E. Saar, L. J. Liivam"agi, J. Einasto

We study the morphology of the richest superclusters from the catalogues of superclusters of galaxies in the 2dF Galaxy Redshift Survey and compare the morphology of real superclusters with model superclusters in the Millennium Simulation. We use Minkowski functionals and shapefinders to quantify the morphology of superclusters: their sizes, shapes, and clum

Suresh Chandra, B. K. Kumthekar

Kumar et al. (2006) obtained a fifth order polynomial in $ω$ for the dispersion relation and pointed out that the calculations preformed by Porter et al. (1994) and by Dwivedi & Pandey (2003) seem to be in error, as they obtained a sixth order polynomial. The energy equation of Dwivedi & Pandey (2003) was dimensionally wrong. Dwivedi & Pandey (2006) correcte

Paul-André Melliès, Samuel Mimram

The notion of innocent strategy was introduced by Hyland and Ong in order to capture the interactive behaviour of lambda-terms and PCF programs. An innocent strategy is defined as an alternating strategy with partial memory, in which the strategy plays according to its view. Extending the definition to non-alternating strategies is problematic, because the t

D. Y. Vodolazov, F. M. Peeters

With increasing applied current we show that the moving vortex lattice changes its structure from a triangular one to a set of parallel vortex rows in a pinning free superconductor. This effect originates from the change of the shape of the vortex core due to non-equilibrium effects (similar to the mechanism of vortex motion instability in the Larkin-Ovchinn

Susumu Takahashi, Gerald Ramian, Mark S. Sherwin, Louis-Claude Brunel

Radiation from an ultra-stable 240 GHz solid-state source has been injected, through an isolator, into the cavity of the University of California Santa Barbara (UCSB) MM-wave free-electron laser (FEL). High-power FEL emission, normally distributed among many of the cavity's longitudinal modes, is concentrated into the single mode to which the solid state

Yusuke Arike

We determine a set of primitive idempotents and the basic algebra of the restricted quantum group $\bar{U}_qsl_2(\mathbb{C})$. As a result, we can show the dimension of the space of symmetric linear functions of $\bar{U}_qsl_2(\mathbb{C})$ is $3p-1$

G. A. El, A. Gammal, E. G. Khamis, R. A. Kraenkel

The theory of optical dispersive shocks generated in propagation of light beams through photorefractive media is developed. Full one-dimensional analytical theory based on the Whitham modulation approach is given for the simplest case of sharp step-like initial discontinuity in a beam with one-dimensional strip-like geometry. This approach is confirmed by nu

Joseph I. Kapusta, Todd Springer

We solve dynamical equations of motion to determine the conditions under which an over-dense region in the early universe will lead to collapse to a black hole, starting from horizon crossing of the over-dense region to the point of gravitational instability. Here we focus on the sensitivity to QCD and electroweak phase transitions. We then solve rate equati

Juergen Reichenbacher

Utilizing only the vertical muon intensity of the Gaisser parameterization of the muon flux at the surface and propagating this energy spectrum underground according to statistical ionization and radiative energy losses, it is possible to calculate the underground muon intensity Crouch curve. In addition, the primary spectral index of the Gaisser parameteriz

A. Chubykalo, A. Espinoza, R. Alvarado-Flores, A. Gutierrez Rodriguez

This is the reply to `COMMENT ON ``HELMHOLTZ THEOREM AND THE V-GAUGE IN THE PROBLEM OF SUPERLUMINAL AND INSTANTANEOUS SIGNALS IN CLASSICAL ELECTRODYNAMICS" BY A. CHUBYKALO ET AL' BY J. A. HERAS [FOUND. PHYS. LETT. vol. 19(6) p. 579 (2006)]

Zhigang Wang, Ping Zhang, Junren Shi

We study the intrinsic orbital magnetization (OM) in antiferromagnets on the distorted face-centered-cubic lattice. The combined lattice distortion and spin frustration induce nontrivial $k$-space Chern invariant, which turns to result in profound effects on the OM properties. We derive a specific relation between the OM and the Hall conductivity, according

M. Gai, D. N. McKinsey, K. Ni, D. A. R. Rubin

The Yale-Weizmann collaboration aims to develop a low-radioactivity (low-background) cryogenic noble liquid detector for Dark-Matter (DM) search in measurements to be performed deep underground as for example carried out by the XENON collaboration. A major issue is the background induced by natural radioactivity of present-detector components including the P

B. R. Dawson

A key feature of the Pierre Auger Observatory is its hybrid design, in which ultra high energy cosmic rays are detected simultaneously by fluorescence telescopes and a ground array. The two techniques see air showers in complementary ways, providing important cross-checks and measurement redundancy. Much of the hybrid capability stems from the accurate geome

Pawel Pralat, Jacques Verstraete, Nicholas Wormald

The $k$-core of a graph is the largest subgraph of minimum degree at least $k$. We show that for $k$ sufficiently large, the $(k + 2)$-core of a random graph $\G(n,p)$ asymptotically almost surely has a spanning $k$-regular subgraph. Thus the threshold for the appearance of a $k$-regular subgraph of a random graph is at most the threshold for the $(k+2)$-cor

P. Szymczak, Marek Cieplak

We incorporate hydrodynamic interactions in a structure-based model of ubiquitin and demonstrate that the hydrodynamic coupling may reduce the peak force when stretching the protein at constant speed, especially at larger speeds. Hydrodynamic interactions are also shown to facilitate unfolding at constant force and inhibit stretching by fluid flows.

Boris Tsirelson

The best approximation by bounded product functions is calculated for some very simple two-valued functions of two variables.

M. Turatto, S. Benetti, A. Pastorello

The discovery of many objects with unprecedented, amazing observational characteristics caused the last decade to be the most prolific period for the supernova research. Many of these new supernovae are transitional objects between existing classes, others well enter within the defined classes, but still show unique properties. This makes the traditional cla

Sofya Raskhodnikova, Dana Ron, Ronitt Rubinfeld, Adam Smith

We raise the question of approximating the compressibility of a string with respect to a fixed compression scheme, in sublinear time. We study this question in detail for two popular lossless compression schemes: run-length encoding (RLE) and Lempel-Ziv (LZ), and present sublinear algorithms for approximating compressibility with respect to both schemes. We

Renato A. Dupke, Nestor Mirabal, Joel N. Bregman, August E. Evrard

Using a combination of Chandra and XMM observations, we confirmed the presence of a significant velocity gradient along the NE/E-W/SW direction in the intracluster gas of the cluster Abell 576. The results are consistent with a previous ASCA SIS analysis of this cluster. The error weighted average over ACIS-S3, EPIC MOS 1 & 2 spectrometers for the maximum ve

Andrea Costa, Rafael Gonzalez

We study the modes and stability of non - isothermal coronal loop models with different intensity values of the equilibrium magnetic field. We use an energy principle obtained via non - equilibrium thermodynamic arguments. The principle is expressed in terms of Hermitian operators and allow to consider together the coupled system of equations: the balance of

Alexios P. Polychronakos

We review the connection between noncommutative gauge theory, matrix models and fluid mechanical systems. The noncommutative Chern-Simons description of the quantum Hall effect and bosonization of collective fermion states are used as specific examples.

Matthias R. Brust, Steffen Rothkugel, Carlos H. C. Ribeiro

Mobile multi-hop ad hoc networks allow establishing local groups of communicating devices in a self-organizing way. However, in a global setting such networks fail to work properly due to network partitioning. Providing that devices are capable of communicating both locally-e.g. using Wi-Fi or Bluetooth-and additionally also with arbitrary remote devices-e.g

Xuezhao Bao, Ali Zhang

We have investigated the migration behaviors of uranium (U) and thorium (Th) in Earth and other terrestrial planets. Theoretical models of U and Th migration have been proposed. These models suggest that the unique features of Earth are closely connected with its unique U and Th migration models and distribution patterns. In the Earth, U and Th can combine w

Alexander Panchenko

The paper is devoted to homogenization of two-phase incompressible viscoelastic flows with disordered microstructure. We study two cases. In the first case, both phases are modeled as Kelvin-Voight viscoelastic materials. In the second case, one phase is a Kelvin-Voight material, and the other is a viscous Newtonian fluid. The microscale system contains the

Alfredo Takashi Suzuki

Different mathematical methods have been applied to obtain the analytic result for the massless triangle Feynman diagram yielding a sum of four linearly independent hypergeometric functions $F_4$. In this paper I work out the diagram and show that that result, though mathematically sound, is not physically correct, because it misses a fundamental physical co

Christoph Puetter, Hyeonjin Doh, Hae-Young Kee

It was suggested that the two consecutive metamagnetic transitions and the large residual resistivity discovered in Sr$_3$Ru$_2$O$_7$ can be understood via the nematic order and its domains in a single layer system. However, a recently reported anisotropy between two longitudinal resistivities induced by tilting the magnetic field away from the c-axis cannot

Edmundo Castillo, Rafael Diaz

We introduce Rota-Baxter categories and construct examples of such structures.

Benjamin F. Collins, Re'em Sari

We present a systematic examination of the changes in semi-major axis caused by the mutual interactions of a group of massive bodies orbiting a central star in the presence of eccentricity dissipation. For parameters relevant to the oligarchic stage of planet formation, dynamical friction keeps the typical eccentricities small and prevents orbit crossing. In

M. L. Manning, J. S. Langer, J. M. Carlson

We model a sheared disordered solid using the theory of Shear Transformation Zones (STZs). In this mean-field continuum model the density of zones is governed by an effective temperature that approaches a steady state value as energy is dissipated. We compare the STZ model to simulations by Shi, et al.(Phys. Rev. Lett. 98 185505 2007), finding that the model

Daniel Krashen, Max Lieblich

We use twisted sheaves to study the problem of index reduction for Brauer classes. In general terms, this problem may be phrased as follows: given a field $k$, a $k$-variety $X$, and a class $α\in \Br(k)$, compute the index of the class $α_{k(X)} \in \Br(X)$ obtained from $α$ by extension of scalars to $k(X)$. We give a general method for computing index red

Kenichi Nakano

A goal of the PHENIX experiment is to obtain the polarized gluon distribution function in the proton. Double helicity asymmetry in multi-particle production with polarized proton-proton collision is measured at midrapidity with RHIC Run 2005 data. This result excludes the maximum positive gluon polarization ("GRSV-max").

Matthias R. Brust, Steffen Rothkugel

Small-worlds represent efficient communication networks that obey two distinguishing characteristics: a high clustering coefficient together with a small characteristic path length. This paper focuses on an interesting paradox, that removing links in a network can increase the overall clustering coefficient. Reckful Roaming, as introduced in this paper, is a

The BaBar Collaboration, B. Aubert

We report on a search for the process B+ -> Kbar*0(892) K+ using 232 10^6 Upsilon(4S) -> BBbar decays collected with the BaBar detector at the PEP-II asymmetric-energy B Factory at SLAC. From a signal yield of 25 +/- 13 [stat] +/- 7 [syst] B+ -> Kbar*0(892) (-> K- pi+) K+ events, we place an upper limit on the branching fraction BF(B+ -> Kbar*0(892) K+) of 1

Howard J. Schnitzer

The loop expansion for the n-point functions of N=4 Yang-Mills theory and N=8 supergravity can be formulated as the loop expansion of scalar field theory with an infinite subclass being the ladder diagrams. We consider the sum of ladder diagrams for gluon-gluon and graviton-graviton scattering in the Regge limit. The reggeization of the gluon and the gravito

Aaron Clauset, Cosma Rohilla Shalizi, M. E. J. Newman

Power-law distributions occur in many situations of scientific interest and have significant consequences for our understanding of natural and man-made phenomena. Unfortunately, the detection and characterization of power laws is complicated by the large fluctuations that occur in the tail of the distribution -- the part of the distribution representing larg

Joachim Kock, André Joyal, Michael Batanin, Jean-François Mascari

We give an elementary and direct combinatorial definition of opetopes in terms of trees, well-suited for graphical manipulation and explicit computation. To relate our definition to the classical definition, we recast the Baez-Dolan slice construction for operads in terms of polynomial monads: our opetopes appear naturally as types for polynomial monads obta

S. Gallerani, A. Ferrara, X. Fan, T. R. Choudhury

We analyze the transmitted flux in a sample of 17 QSOs spectra at 5.74<zem<6.42 to obtain tighter constraints on the volume-averaged neutral hydrogen fraction, xHI, at z~6. We study separately the narrow transmission windows (peaks) and the wide dark portions (gaps) in the observed absorption spectra. By comparing the statistics of these spectral features wi

Kater W. Murch, Kevin L. Moore, Subhadeep Gupta, Dan M. Stamper-Kurn

Current research on micro-mechanical resonators strives for quantum-limited detection of the motion of macroscopic objects. Prerequisite to this goal is the observation of measurement backaction consistent with quantum metrology limits. However, thermal noise presently dominates measurements and precludes ground-state preparation of the resonator. Here we es

MiniBooNE collaboration

The observation of neutrino oscillations is clear evidence for physics beyond the standard model. To make precise measurements of this phenomenon, neutrino oscillation experiments, including MiniBooNE, require an accurate description of neutrino charged current quasi-elastic (CCQE) cross sections to predict signal samples. Using a high-statistics sample of m

Subhadeep Gupta, Kevin L. Moore, Kater W. Murch, Dan M. Stamper-Kurn

We report on Kerr nonlinearity and dispersive optical bistability of a Fabry-Perot optical resonator due to the displacement of ultracold atoms trapped within. In the driven resonator, such collective motion is induced by optical forces acting upon up to $10^5$ $^{87}$Rb atoms prepared in the lowest band of a one-dimensional intracavity optical lattice. The

Ibrahim Abou Hamad, Daniel T. Robb, Mark A. Novotny, Per Arne Rikvold

We propose a new, cyclic-voltammetry based experimental technique that can not only differentiate between discontinuous and continuous phase transitions in an adsorbate layer, but also quite accurately recover equilibrium behavior from dynamic analysis of systems with a continuous phase transition. The Electrochemical first-order reversal curve (EC-FORC) dia

Ludovic Berthier, Robert L. Jack

Dynamic heterogeneity in glass-formers has been related to their static structure using the concept of dynamic propensity. We re-examine this relationship by analyzing dynamical fluctuations in two atomistic glass-formers and two theoretical models. We introduce quantitative statistical indicators which show that the dynamics of individual particles cannot b

Erich Poppitz, Yanwen Shang

We show, using exact lattice chirality, that partition functions of lattice gauge theories with vectorlike fermion representations can be split into &#34;light&#34; and &#34;mirror&#34; parts, such that the &#34;light&#34; and &#34;mirror&#34; representations are chiral. The splitting of the full partition function into &#34;light&#34; and &#34;mirror&#34; i

Triston Dougall, Stuart D. Wick

We calculate the lowest order cross--section for Dirac magnetic monopole production from photon fusion in p p-bar collisions at sqrt{s}=1.96 TeV, p p collisions at sqrt{s}=14 TeV, and we compare photon fusion with Drell--Yan (DY) production. We find the total photon fusion cross--section is comparable with DY at sqrt{s}=1.96 TeV and dominates DY by a factor

V. Mateu, J. Portoles

We perform an analysis of the form factors that rule the structure-dependent amplitude in the radiative pion decay. The resonance contributions to pion -> e nu_e gamma decays are computed through the proper construction of the vector and axial-vector form factors by setting the QCD driven asymptotic properties of the three-point Green functions VVP and VAP,

Masahiro Takeoka, Masahide Sasaki

We address the limit of the Gaussian operations and classical communication in the problem of quantum state discrimination. We show that the optimal Gaussian strategy for the discrimination of the binary phase shift keyed (BPSK) coherent signal is a simple homodyne detection. We also propose practical near-optimal quantum receivers that beat the BPSK homodyn

Bruce I. Cohen, Andris M. Dimits, William M. Nevins

This comment clarifies the relation of the research in a recently published article [Phys. Plasmas 14, 042503 (2007)] to other prior publications addressing the inclusion of electromagnetic and drift-kinetic electron physics in gyrokinetic simulation, raises a concern related to the inclusion of kinetic electrons in a system with magnetic shear, and discusse

Alexei Borodin, Grigori Olshanski

The present paper originated from our previous study of the problem of harmonic analysis on the infinite symmetric group. This problem leads to a family {P_z} of probability measures, the z-measures, which depend on the complex parameter z. The z-measures live on the Thoma simplex, an infinite-dimensional compact space which is a kind of dual object to the i

Dinesh Singh

A perturbation method to analytically describe the dynamics of a classical spinning particle, based on the Mathisson-Papapetrou-Dixon (MPD) equations of motion, is presented. By a power series expansion with respect to the particle&#39;s spin magnitude, it is shown how to obtain in general form an analytic representation of the particle&#39;s kinematic and d

Yasuaki Hikida, Volker Schomerus

There exists an intriguing relation between genus zero correlation functions in the H^+_3 WZNW model and in Liouville field theory. We provide a path integral derivation of the correspondence and then use our new approach to generalize the relation to surfaces of arbitrary genus g. In particular we determine the correlation functions of N primary fields in t

Simone Diverio

Let $n=2,3,4,5$ and let $X$ be a smooth complex projective hypersurface of $\mathbb P^{n+1}$. In this paper we find an effective lower bound for the degree of $X$, such that every holomorphic entire curve in $X$ must satisfy an algebraic differential equation of order $k=n=\dim X$, and also similar bounds for order $k>n$. Moreover, for every integer $n\ge 2$

Marie-Noëlle Célérier

Observational cosmology provides us with a large number of high precision data which are used to derive models trying to reproduce ``on the mean&#39;&#39; our observable patch of the Universe. Most of these attempts are achieved in the framework of a Friedmann-Lemaître cosmology where large scale homogeneity is assumed. However, we know, from the observation

D. Kharzeev, A. Zhitnitsky

We examine the recent suggestion that P- and CP-odd effects in QCD matter can induce electric charge asymmetry with respect to reaction plane in relativistic heavy ion collisions. General arguments are given which confirm that the angular momentum of QCD matter in the presence of non-zero topological charge should induce an electric field aligned along the a

L. Bonora, C. Maccaferri, R. J. Scherer Santos, D. D. Tolla

This paper is primarily devoted to the ghost wedge states in string field theory formulated with the oscillator formalism. Our aim is to prove, using such formalism, that the wedge states can be expressed as |n> = exp[{2-n}/2 ({\cal L}_0+{\cal L}_0^\daggert)]|0>, separately in the matter and ghost sector. This relation is crucial for instance in the proof of

Ph. Brax, C. van de Bruck, A. C. Davis

We review some of the properties of chameleon theories. Chameleon fields are gravitationally coupled to matter and evade gravitational tests thanks to two fundamental properties. The first one is the density dependence of the chameleon mass. In most cases, in a dense environment, chameleons are massive enough to induce a short ranged fifth force. In other ca

Kartick Tarafder, Atisdipankar Chakrabarti, Subhradip Ghosh, Biplab Sanyal

In this communication we have studied the electronic structure, magnetic and optical properties of bcc \fecr alloys in the ferromagnetic phase. We have used the augmented space recursion technique coupled with tight-binding linearized muffin-tin orbital technique (TB-LMTO-ASR) as well as the coherent-potential approximation based on the Korringa-Kohn-Rostock

Gesualdo Delfino, Paolo Grinza

The q-state Potts field theory describes the universality class associated to the spontaneous breaking of the permutation symmetry of q colors. In two dimensions it is defined up to q=4 and exhibits duality and integrability away from critical temperature in absence of magnetic field. We show how, when a magnetic field is switched on, it provides the simples