December 2006 arXiv papers — page 19

T. Bereznyak, P. Svetlov

We prove that distortion of a knotted curve in $\R^3$ is great than 4.76. This improves a result obtained by John M. Sullivan and Elizabeth Denne in \cite{DS}.

Gil Bor, Richard Montgomery

Associated to the problem of rolling one surface along another there is a five-manifold M with a rank two distribution. If the two surfaces are spheres then M is the product of the rotation group SO_3 with the two-sphere and its distribution enjoys an obvious symmetry group; the product of two SO_3's, one for each sphere. But if the ratio of radii of the

Oisin A. P. Mac Conamhna, Eoin O Colgain

We perform a systematic study, in eleven dimensional supergravity, of the geometry of wrapped brane configurations admitting $AdS_2$ limits. Membranes wrapping holomorphic curves in Calabi-Yau manifolds are found to exhibit some novel features; in particular, for fourfolds or threefolds, the gravitational effect of the branes on the overall transverse space

Don N. Page

A complete model of the universe needs at least three parts: (1) a complete set of physical variables and dynamical laws for them, (2) the correct solution of the dynamical laws, and (3) the connection with conscious experience. In quantum cosmology, item (1) is often called a `theory of everything,' and item (2) is the quantum state of the cosmos. Hartl

Don N. Page

A brief review of Hawking radiation and black hole thermodynamics is given, based largely upon hep-th/0409024.

Bobby Samir Acharya, Francesco Benini, Roberto Valandro

Warped models, originating with the ideas of Randall and Sundrum, provide a fascinating extension of the standard model with interesting consequences for the LHC. We investigate in detail how string theory realises such models, with emphasis on fermion localisation and the computation of Yukawa couplings. We find, in contrast to the 5d models, that fermions

C. P. Martin, D. Sanchez-Ruiz, C. Tamarit

We discuss the renormalizability of the noncommutative U(1)Higgs-Kibble model formulated within the enveloping-algebra approach. We consider both the phase of the model with unbroken gauge symmetry and the phase with spontaneously broken gauge symmetry. We show that against all odds the gauge sector of the model is always one-loop renormalizable at first ord

Lee Smolin

The problem of making predictions from theories that have landscapes of possible low energy parameters is reviewed. Conditions for such a theory to yield falsifiable predictions for doable experiments are given. It is shown that the hypothesis of cosmological natural selection satisfies these conditions, thus showing that it is possible to continue to do phy

G. Sardanashvily

In contrast with QFT, classical field theory can be formulated in a strict mathematical way if one defines even classical fields as sections of smooth fiber bundles. Formalism of jet manifolds provides the conventional language of dynamic systems (nonlinear differential equations and operators) on fiber bundles. Lagrangian theory on fiber bundles is algebrai

Dirk Kreimer, Karen Yeats

In this paper we show that there is a Lipatov bound for the radius of convergence for superficially divergent one-particle irreducible Green functions in a renormalizable quantum field theory if there is such a bound for the superficially convergent ones. The radius of convergence turns out to be ${\rm min}\{ρ,1/b_1\}$, where $ρ$ is the bound on the converge

Leonard S. Kisslinger

We derive the energy asymmetry given the proto-neutronstar during the time when the neutrino sphere is near the surface of the proto-neutron star, using the modified URCA process. The electrons produced with the anti-neutrinos are in Landau levels due to the strong magnetic field, and this leads to asymmetry in the neutrino momentum, and a pulsar kick. Our m

Daniel Phalen, Brooks Thomas, James D. Wells

For a Standard Model Higgs boson with mass between 115 GeV and 150 GeV, the two-photon decay mode is important for discovery at the Large Hadron Collider (LHC). We describe the interactions of a light Higgs boson in a more model-independent fashion, and consider the parameter space where there is no two-photon decay mode. We argue from generalities that anal

S. Y. Choi, H. E. Haber, J. Kalinowski, P. M. Zerwas

Motivated by grand unified theories and string theories we analyze the general structure of the neutralino sector in the USSM, an extension of the Minimal Supersymmetric Standard Model that involves a broken extra U(1) gauge symmetry. This supersymmetric U(1)-extended model includes an Abelian gauge superfield and a Higgs singlet superfield in addition to th

A. K. Ciftci, R. Ciftci, H. Duran Yildiz, S. Sultansoy

Possible single productions of the fourth standard model family charged leptons via anomalous interactions at the future ep colliders are studied. Signatures of such anomalous processes and backgrounds are discussed in detail.

G. Lambiase

The Standard Model Extension with the inclusion of gravity is studied in the framework of the gravitational baryogenesis, a mechanism to generate the baryon asymmetry based on the coupling between the Ricci scalar curvature and the baryon current (\partial_μR)J^μ. We show that, during the radiation era of the expanding Universe, a non vanishing time derivati

Takehiko Asaka, Koji Ishiwata, Takeo Moroi

We consider the minimal supersymmetric standard model (MSSM) extended by introducing three right-handed (s)neutrinos to account for neutrino masses in the oscillation experiments. Assuming that the neutrino masses are purely Dirac-type, the lightest right-handed sneutrino $\tilde ν_R$ can be the lightest superparticle (LSP), which is a good candidate of cold

M. Anselmino, U. D'Alesio, S. Melis, F. Murgia

We consider the recent RHIC data on the transverse single spin asymmetry (SSA) A_N, measured in p(transv. polarized) p --> pion X processes at mid-rapidity by the PHENIX Collaboration. We analyze this experimental information within a hard scattering approach based on a generalized QCD factorization scheme, with unintegrated, transverse momentum dependent (T

U. D'Alesio, F. Murgia

Our understanding of the transverse spin structure of hadrons might definitely get improved by the information we gather on transverse momentum dependent (TMD) distributions. These new functions could also be crucial for a description of the observed transverse single spin asymmetries (SSA). In a hard scattering model for inclusive hadronic reactions, based

I Collaboration

From 56 days of data taking in 2002, the NA48/1 experiment observed 6316 Xi0 --> Sigma+ e- nubar candidates (with the subsequent Sigma+ --> p pi0 decay) and 555 anti-Xi0 --> anti-Sigma+ e+ nu candidates with background contamination of 215+-44 and 136+-8 events, respectively. From these samples, the branching ratios BR(Xi0 --> Sigma+ e- nubar)= (2.51+-0.03st

H. Aksakal, A. K. Ciftci, Z. Nergiz, D. Schulte

Gamma-proton collisions allow unprecedented investigations of the low x and high $Q^{2}$ regions in quantum chromodynamics. In this paper, we investigate the luminosity for "ILC"$\times$LHC ($\sqrt{s_{ep}}=1.3$ TeV) and "CLIC"$\times$LHC ($\sqrt{s_{ep}}=1.45$ TeV) based $γp$ colliders. Also we determine the laser properties required for high

Florian Girelli, Etera R. Livine

Deformed Special Relativity is usually presented as a deformation of Special Relativity accommodating a new universal constant, the Planck mass, while respecting the relativity principle. In order to avoid some fundamental problems (e.g. soccer ball problem), we argue that we should switch point of view and consider instead the Newton constant $G$ as the uni

Xiaoning Wu, Yu Shang

We consider the general asymptotic expression of stationary space-time. Using Killing equation, we reduce the dynamical freedom of Einstein equation to the in-going gravitational wave $Ψ_0$. The general form of this function can be got. With the help of asymptotically algebraic special condition, we prove that all Newman-Penrose constants vanish.

Vita Hinze-Hoare

A number of papers have been reviewed in the areas of HCI, CSCW, CSCL. These have been analyzed with a view to extract the ideas relevant to a consideration of user interactions in a collaborative on line laboratory which is being under development for use in the ITO BSc course at Southampton University. The construction of new theoretical models is to be ba

Lester Ingber

There are several kinds of non-invasive imaging methods that are used to collect data from the brain, e.g., EEG, MEG, PET, SPECT, fMRI, etc. It is difficult to get resolution of information processing using any one of these methods. Approaches to integrate data sources may help to get better resolution of data and better correlations to behavioral phenomena

Roberto Bagnara, Patricia M. Hill, Enea Zaffanella

Since its inception as a student project in 2001, initially just for the handling (as the name implies) of convex polyhedra, the Parma Polyhedra Library has been continuously improved and extended by joining scrupulous research on the theoretical foundations of (possibly non-convex) numerical abstractions to a total adherence to the best available practices

Ender Tekin, Aylin Yener

We consider the General Gaussian Multiple Access Wire-Tap Channel (GGMAC-WT). In this scenario, multiple users communicate with an intended receiver in the presence of an intelligent and informed eavesdropper who is as capable as the intended receiver, but has different channel parameters. We aim to provide perfect secrecy for the transmitters in this multi-

Thierry Despeyroux

This document describes a couple of tools that help to quickly design and develop computer (formalized) languages. The first one use Flex to perform lexical analysis and the second is an extention of Prolog DCGs to perfom syntactical analysis. Initially designed as a new component for the Centaur system, these tools are now available independently and can be

Manas Tungare, Pardha S. Pyla, Manuel Pérez-Quiñones, Steve Harrison

Today, people use multiple devices to fulfill their information needs. However, designers design each device individually, without accounting for the other devices that users may also use. In many cases, the applications on all these devices are designed to be functional replicates of each other. We argue that this results in an over-reliance on data synchro

Joydeep Bhattacharjee, Shobhana Narasimhan, Umesh V Waghmare

In the past two decades, geometric phases have provided a powerful new way of looking at quantum mechanical systems, manifesting themselves in subtle but observable ways. Here, we use them to define a versatile function ("distribution of electron charge centres" or DECC) which can be easily evaluated and interpreted, providing information about elect

J. A. Tesser, R. T. Lopes, A. P. Vieira, L. L. Goncalves

This paper presents a fractal analysis of radiographic patterns obtained from specimens with three types of inserted welding defects: lack of fusion, lack of penetration, and porosity. The study focused on patterns of carbon steel beads from radiographs of the International Institute of Welding (IIW). The radiographs were scanned using a greyscale with 256 l

V. Turkowski, J. K. Freericks

We present a review of our recent work in extending the successful dynamical mean-field theory from the equilibrium case to nonequilibrium cases. In particular, we focus on the problem of turning on a spatially uniform, but possibly time varying, electric field (neglecting all magnetic field effects). We show how to work with a manifestly gauge-invariant for

P. H. Lundow, K. Markström

In this paper we discuss how partial knowledge of the density of states for a model can be used to give good approximations of the energy distributions in a given temperature range. From these distributions one can then obtain the statistical moments corresponding to eg the internal energy and the specific heat. These questions have gained interest apropos o

Wayne M. Saslow, Davide E. Galli, Luciano Reatto

We extend the one-body phase function upper bound on the superfluid fraction in a periodic solid (a spatially ordered supersolid) to include two-body phase correlations. The one-body current density is no longer proportional to the gradient of the one-body phase times the one-body density, but rather it depends also on two-body correlation functions. The equ

O. V. Fefelov, J Bergli, Y M Galperin

We calculate the dependence of heat capacity of a free standing thin membrane on its thickness and temperature. A remarkable fact is that for a given temperature there exists a minimum in the dependence of the heat capacity on the thickness. The ratio of the heat capacity to its minimal value for a given temperature is a universal function of the ratio of th

V. Krakoviack

In the framework of the polymer reference interaction site model (PRISM) extended to incorporate the centers of mass (CM) of the groups of monomers constitutive of the macromolecules as auxiliary sites, a general relationship between the monomer-monomer and CM-CM pair correlation functions is derived for arbitrary mixtures of macromolecules of arbitrary stru

T. E. Saunders, J. T. Chalker

We investigate the consequences for geometrically frustrated antiferromagnets of weak disorder in the strength of exchange interactions. Taking as a model the classical Heisenberg antiferromagnet with nearest neighbour exchange on the pyrochlore lattice, we examine low-temperature behaviour. We show that random exchange generates long-range effective interac

Maxim Yu. Kharitonov, Mikhail V. Feigel'man

The authors of a recent Letter [Phys. Rev. Lett. 97, 137001 (2006)] observed enhancement of the critical supercurrent of superconducting nanowires in external magnetic field. They attributed the obtained behavior to the presence of magnetic moments in the samples. In this Comment we derive the conditions, crucial for the existence of the observed behavior, a

Antonio M. Garcia-Garcia, Emilio Cuevas

We study the dependence on the spatial dimensionality of different quantities relevant in the description of the Anderson transition by combining numerical calculations in a $3 \leq d \leq 6$ disordered tight binding model with theoretical arguments. Our results indicate that, in agreement with the one parameter scaling theory, the upper critical dimension f

Rolf-Juergen Merath, Udo Seifert

Fluctuation spectra of fluid compound membrane systems are calculated. The systems addressed contain two (or more) almost parallel membranes that are connected by harmonic tethers or by a continuous, harmonic confining potential. Additionally, such a compound system can be attached to a supporting substrate. We compare quasi-analytical results for tethers wi

S. G. Lebedev, V. E. Yants, A. S. Lebedev

The satisfactory explanation of abnormal electromagnetics in thin graphite-like carbon films till now is absent. The most comprehensible explanation may be the high-temperature superconductivity (HTSC). Times of spasmodic switching of electrical conductivity are measured in this work in graphite-like nanostructured carbon films, produced by methods of the ca

Ying Xu, Xingqiang Shi, Zhi Zeng, Zhao Yang Zeng

We present first-principles calculations for the transport properties of monoatomic Al wires sandwiched between Al(100) electrodes. The conductance of the monoatomic Al wires oscillates with the number of the constituent atoms as a function of the wire length, either with a period of four-atom for wires with the typical interatomic spacing or a period of six

Tsutomu Indei

Viscoelastic and thermodynamic properties of transient gels formed by telechelic polymers are studied on the basis of the transient network theory that takes account of the correlation among polymer chains via network junctions. The global information of the gel is incorporated into the theory by introducing the elastically effective chains according to the

Sangeeta Saini, Somnath Bhowmick, Vijay B. Shenoy, Biman Bagchi

Long range resonance energy transfer (RET) between a donor and an acceptor molecule is increasingly being used in many areas of biological and material science. The phenomenon is used to monitor the in vivo separation between different (bio) polymers/units of (bio) polymers and hence the dynamics of various biomolecular processes. Because of the sensitivity

Alastair Windus, Henrik Jeldtoft Jensen

We introduce a model for a population on a lattice with diffusion and birth/death according to 2A->3A and A->0 for a particle A. We find that the model displays a phase transition from an active to an absorbing state which is continuous in 1+1 dimensions and of first-order in higher dimensions in agreement with the mean field equation. For the 1+1 dimensiona

Shengqiang Zhou, K. Potzger, H. Reuther, G. Talut

In this paper, a correlation between structural and magnetic properties of Fe implanted ZnO is presented. High fluence Fe^+ implantation into ZnO leads to the formation of superparamagnetic alpha-Fe nanoparticles. High vacuum annealing at 823 K results in the growth of alpha-Fe particles, but the annealing at 1073 K oxidized the majority of the Fe nanopartic

Sungchul Kwon, Yup Kim

We investigate the kinetics of uniformly driven $A+B \to 0$ reaction with mass-dependent fragmentation in one dimension. In this model, the fragmented mass $m$ of a site with mass $n_i$ is given as $m=n^λ_i$, and it is driven to the one direction. When opposite species masses occupy the same site, mass reaction takes place instantaneously. Since the fragment

Z. Usatenko, J. -U. Sommer

The influence of long-range correlated surface and decaying near surface disorder with quenched defects is studied. We consider a correlation function for the defects of the form $\frac{e^{-z/ξ}}{r^{a}}$, where $a<d-1$ and $z$ being the coordinate in the direction perpendicular to the surface and $r$ denotes the distance parallel to the surface. We investiga

U. Kuhl, R. Hoehmann, H. -J. Stoeckmann, S. Gnutzmann

Nodal domains are studied both for real $ψ_R$ and imaginary part $ψ_I$ of the wavefunctions of an open microwave cavity and found to show the same behavior as wavefunctions in closed billiards. In addition we investigate the variation of the number of nodal domains and the signed area correlation by changing the global phase $ϕ_g$ according to $ψ_R+iψ_I=e^{i

Jun Hashimoto, Motohide Tamura, Ryo Kandori, Nobuhiko Kusakabe

We present the polarization images in the $J$, $H$, & $Ks$ bands of the Orion Molecular Cloud 1 South region. The polarization images clearly show at least six infrared reflection nebulae (IRNe) which are barely seen or invisible in the intensity images. Our polarization vector images also identify the illuminating sources of the nebulae: IRN 1 & 2, IRN 3, 4

Minh T. Huynh, Carole A. Jackson, Ray P. Norris

Deep radio observations of a wide region centred on the Hubble Deep Field South have been performed, providing one of the most sensitive set of radio observations acquired on the Australia Telescope Compact Array to date. A central rms of ~10 microJy is reached at four frequencies (1.4, 2.5, 5.2 and 8.7 GHz). In this paper the full source catalogues from the

Jonathan Granot

Many Swift GRBs show an early phase of shallow decay in their X-ray afterglows, lasting from $t \sim 10^{2.5} $s to $\sim 10^4 $s after the GRB, where the flux decays as $\sim t^{-0.2}-t^{-0.8}$. This is perhaps the most mysterious of the new features discovered by Swift in the early X-ray afterglow, since it is still not clear what causes it. I discuss diff

Lynn D. Matthews, Mark J. Reid

We present the results of a VLA search for HI emission in the circumstellar envelopes of five nearby AGB stars: RS Cnc, IRC+10216, EP Aqr, R Cas, and R Aqr. We have detected emission coincident in both position and velocity with RS Cnc, implying that the emission arises from its extended envelope. For R Cas, we detected weak emission that peaks at the stella

Stéphane Blondin, John L. Tonry

We present an algorithm to identify the types of supernova spectra, and determine their redshift and phase. This algorithm, based on the correlation techniques of Tonry & Davis, is implemented in the SuperNova IDentification code (SNID). It is used by members of the ESSENCE project to determine whether a noisy spectrum of a high-redshift supernova is indeed

M. Cervino, V. Luridiana, L. Jamet

The surface brightness fluctuations (SBF) method is a statistical method applied on image pixels in different bands. This contribution aims to distinguish between the observational (statistical) method and the theoretical (probabilistic) method based on stellar population synthesis and needed for the calibration of observational SBF. We find that the commonl

Lei Hao, D. W. Weedman, H. W. W. Spoon, J. A. Marshall

A sample of 196 AGNs and ULIRGs observed by the Infrared Spectrograph (IRS) on Spitzer is analyzed to study the distribution of the strength of the 9.7 micron silicate feature. Average spectra are derived for quasars, Seyfert 1 and Seyfert 2 AGNs, and ULIRGs. We find that quasars are characterized by silicate features in emission and Seyfert 1s equally by em

David A. Chamulak, Edward F. Brown, Francis X. Timmes

Carbon-oxygen white dwarfs contain neon-22 formed from alpha-captures onto nitrogen during core He burning in the progenitor star. In a white dwarf (type Ia) supernova, the neon-22 abundance determines, in part, the neutron-to-proton ratio and hence the abundance of radioactive nickel-56 that powers the lightcurve. The neon-22 abundance also changes the burn

Mosser Benoit, Aristidi Eric

We report the observations of the clear sky fraction at the Concordia station during winter 2006, and derive from it the duty cycle for astronomical observations. Performance in duty cycle and observation duration promotes Dome C for efficient asteroseismic observations. This performance is analyzed and compared to network observation. For network observatio

A. Panaitescu, P. Kumar

The prompt optical emission of GRB 990123 was uncorrelated to the gamma-ray light-curve and exhibited temporal properties similar to those of the steeply-decaying, early X-ray emission observed by Swift at the end of many bursts. These facts suggest that the optical counterpart of GRB 990123 was the large-angle emission released during (the second pulse of)

G. F. Burgio, M. Baldo, O. E. Nicotra, H. -J. Schulze

We study the structure of protoneutron stars within the finite temperature Brueckner-Bethe-Goldstone many-body theory. If nucleons, hyperons, and leptons are present in the stellar core, we find that neutrino trapping stiffens considerably the equation of state, because hyperon onsets are shifted to larger baryon density. However, the value of the critical m

N. A. Tomov, M. T. Tomova, D. V. Bisikalo

High resolution data in the region of the line Halpha have been obtained at the time of the light maximum and after it of the 2006 optical outburst of the symbiotic binary Z And. A blue-shifted absorption component indicating outflow velocity of about 1400 km/s as well as additional emission components with similar velocities, situated on the two sides of th

A. M. T. Pollock

XMM-Newton observations of the O supergiant zeta Orionis (O9.7 Ib) extend knowledge of its high-resolution spectrum beyond the CVI line at 33.7 Angstroms and suggest a new framework for the interpretation of the X-ray spectra of single hot stars. All the lines are broad and asymmetric with similar velocity profiles. X-rays probably originate in the wind&#39;

A. Poncelet, C. Doucet, G. Perrin, H. Sol

We present a speckle analysis of the active galactic nucleus (AGN) inside the archetype Seyfert type 2 galaxy NGC 1068. This study is based on 12.8 microns images obtained with the burst mode of VISIR (the Very Large Telescope Imager and Spectrometer in the InfraRed). The interferometric processing allows to push the resolution far below the diffraction limi

Guia Pastorini

The very high spatial resolution provided by Adaptive Optics assisted spectroscopic observations at 8m-class telescopes (e.g. with SINFONI at the VLT) will allow to greatly increase the number of direct black hole (BH) mass measurements which is currently very small. This is a fundamental step to investigate the tight link between galaxy evolution and BH gro

HESS Collaboration, F. A. Aharonian

The shell-type supernova remnant RX J0852.0-4622 was observed with the High Energy Stereoscopic System (H.E.S.S.) of Atmospheric Cherenkov Telescopes between December 2004 and May 2005 for a total observation time of 33 hours, above an average gamma-ray energy threshold of 250 GeV. The angular resolution of ~0.06 degree (for events triggering 3 or 4 telescop

F P Keenan, D B Jess, K M Aggarwal, R J Thomas

Recent fully relativistic calculations of radiative rates and electron impact excitation cross sections for Fe {\sc xiii} are used to generate emission-line ratios involving 3s$^{2}$3p$^{2}$--3s3p$^{3}$ and 3s$^{2}$3p$^{2}$--3s$^{2}$3p3d transitions in the 170--225 Åand 235--450 Åwavelength ranges covered by the Solar Extreme-Ultraviolet Research Telescope a

Edward Malec, Krzysztof Roszkowski

We investigate the newtonian stationary accretion of a polytropic perfect fluid onto a central body with a hard surface. The selfgravitation of the fluid and its interaction with luminosity is included in the model. We find that for a given luminosity, asymptotic mass and temperature of the fluid there exist two solutions with different cores.

Th. Boller, I. Balestra, W. Kollatschny

We report on the first XMM-Newton observation of the bright Narrow-Line Seyfert 1 galaxy Mrk 110. We find a narrow Fe K fluorescent line, a broad component FWHM ~ 16500 km/s of the OVII triplet, either due to infall motions or gravitational redshift effects in the vicinity of the central black hole, a Comptonized accretion disc layer, and a strong starburst

Magdalena Kunert-Bajraszewska, Andrzej Marecki

Multi-frequency 1.7, 5 and 8.4-GHz VLBA observations of a radio-loud broad absorption line (BAL) quasar 1045+352 are presented. It is a young compact steep spectrum (CSS) object and its asymmetric, two-sided morphology on a scale of several hundred parsecs, extending in two different directions, may suggest intermittent activity. The young age and unusual mo

Radoslaw Smolec, Pawel Moskalik

Using nonlinear hydrocodes we have calculated single mode saturation amplitudes for beta Cephei models. Predicted saturation amplitudes are systematically higher than amplitudes observed in beta Cephei variables, even in monoperiodic ones. We argue that collective saturation of the pulsation instability by a dozen or so acoustic modes brings the theoretical

M. Nardini, G. Ghisellini, G. Ghirlanda, F. Tavecchio

We studied the behaviour of the optical afterglow lightcurves of a sample of 24 Gamma--Ray Bursts (GRBs) with known redshift and published estimates of the optical extinction in the source frame, detected before the SWIFT satellite launch. We found an unexpected clustering of the optical luminosities at 12 hours in the source frame. The distribution of the o

D. Porquet, J. N. Reeves, A. Markowitz, T. J. Turner

(abridged) The radio-quiet quasar PG1416-129 (z=0.129) exhibits atypical optical and X-ray properties. Between 1990 and 2000, in response to its optical continuum decrease, the ``classical&#39;&#39; broad component of Hbeta almost completely disappeared, with a factor of 10 decrease in the line flux. In the X-ray band, this object was observed by Ginga in 19

M. Hilker, H. Baumgardt, L. Infante, M. Drinkwater

Aims. We determine masses and mass-to-light ratios of five ultra-compact dwarf galaxies and one dwarf elliptical nucleus in the Fornax cluster from high resolution spectroscopy. Methods. Velocity dispersions were derived from selected wavelength regions using a direct-fitting method. To estimate the masses of the UCDs a new modelling program has been develop

E. A. Evstigneeva, M. D. Gregg, M. J. Drinkwater, M. Hilker

We present new imaging and spectroscopic observations of six ultra-compact dwarf (UCD) galaxies in the Virgo Cluster, along with re-analysed data for five Fornax Cluster UCDs. These are the most luminous UCDs: -14<Mv<-12 mag. Our HST imaging shows that most of the UCDs have shallow or steep cusps in their cores; only one UCD has a flat ``King&#39;&#39; core.

C. Codella, S. Cabrit, F. Gueth, R. Cesaroni

We mapped the HH212 Class 0 outflow in SiO(2--1, 5--4) and continuum using the PdBI in its extended configurations. The unprecedented angular resolution (down to 0.34&#34;) allows accurate comparison with a new, deep H2 image obtained at the VLT. The SiO emission is confined to a highly-collimated bipolar jet (width 0.35&#34;) along the outflow axis. The jet

M. A. Requena-Torres, N. Marcelino, I. Jiménez-Serra, J. Martín-Pintado

We present high sensitivity observations of the complex organic molecules (COMs) CH3OH, C2H5OH, HCOOCH3, HCOOH and H2CO and of SiO toward the quiescent dark cloud L183 and the molecular outflow L1448-mm. We have not detected C2H5OH, HCOOCH3 and SiO in L183 and in the quiescent gas of L1448-mm. The abundances of CH3OH, H2CO and SiO are enhanced by factors 4-2

A. F. Lanza, A. S. Bonomo, M. Rodono&#39;

The space missions MOST, COROT and Kepler are going to provide us with high-precision optical photometry of solar-like stars with time series extending from tens of days to several years. They can be modelled to obtain information on stellar magnetic activity by fitting the rotational modulation of the stellar flux produced by the brightness inhomogeneities

Yoshitaka Murata, Takahiko Matsubara

A method of counts-in-cells analysis of galaxy distribution is investigated with arbitrary smoothing functions in obtaining the galaxy counts. We explore the possiblity of optimizing the smoothing function, considering a series of $m$-weight Epanechnikov kernels. The popular top-hat and Gaussian smoothing functions are two special cases in this series. In th

Gijs Verdoes Kleijn, Ronald Vermeij, Edwin Valentijn, Koen Kuijken

The OmegaCAM wide-field imager will start operations at the ESO VLT Survey Telescope at Paranal, Chile, in 2007. The photometric calibration of OmegaCAM data depends on standard star measurements that cover the complete 1 square degree FoV of OmegeaCAM. A catalog fullfilling this requirement for eight Landolt equatorial fields, denoted the OmegaCAM Secondary

Marcelo D. Mora, Soeren S. Larsen, Markus Kissler-Patig

We present results from ACS and WFPC observations in the low luminosity galaxy NGC 45. We identified 28 young star cluster candidates. While the exact values of age, mass, and extinction depend somewhat on the choice of SSP models, we find no young clusters with masses higher than a few 1000 Msun for any model choice. We derive the luminosity function of you

C. C. Dow-Hygelund, B. P. Holden, R. Bouwens, G. D. Illingworth

We report on deep spectroscopy using LRIS on Keck I and FORS2 on the VLT of a sample of 22 candidate z~6 Lyman Break galaxies (LBGs) selected by the i-z> 1.3 dropout criterion. Redshifts could be measured for eight objects. These redshifts are all in the range z = 5.5 - 6.1, confirming the efficiency of the i-z color selection technique. Six of the confirmed

Rufus Willett

We provide an expository account of Guoliang Yu&#39;s property A. The piece starts from the basic definitions, and goes on to discuss closure properties of the class of property A spaces (and groups) and the relationship of property A to coarse embeddability problems, operator theory, and amenability. It finishes with some examples of non-property A spaces.

Nicholas M. Ball, Robert J. Brunner, Adam D. Myers, Natalie E. Strand

We apply instance-based machine learning in the form of a k-nearest neighbor algorithm to the task of estimating photometric redshifts for 55,746 objects spectroscopically classified as quasars in the Fifth Data Release of the Sloan Digital Sky Survey. We compare the results obtained to those from an empirical color-redshift relation (CZR). In contrast to pr

Axel Gandy

This paper introduces an open-ended sequential algorithm for computing the p-value of a test using Monte Carlo simulation. It guarantees that the resampling risk, the probability of a different decision than the one based on the theoretical p-value, is uniformly bounded by an arbitrarily small constant. Previously suggested sequential or non-sequential algor

Kevin Wood, C. Van den Broeck, R. Kawai, Katja Lindenberg

We derive an exact expression for entropy production during effusion of an ideal gas driven by momentum transfer in addition to energy and particle flux. Following the treatment in Phys. Rev. E Vol. 74, 021117 (2006), we construct a master equation formulation of the process and explicitly verify the thermodynamic fluctuation theorem, thereby directly exhibi

Pawel Danielewicz, Scott Pratt

The dependence of inter-particle correlations on the orientation of particle relative-momentum can yield unique information on the space-time features of emission in reactions with multiparticle final states. In the present paper, the benefits of a representation and analysis of the three-dimensional correlation information in terms of surface spherical harm

Vladislav Vysotsky

Let S_i be a random walk with standard exponential increments. We call \sum_{i=1}^k S_i its k-step area. The random variable V = \inf_{k \ge 1} \frac{2}{k(k+1)} \sum_{i=1}^k S_i plays important role in the study of so-called one-dimensional sticky particles model. We find the distribution of V and prove that P(V > t) = \sqrt{1-t} exp(-t/2) for t in [0,1]. We

A. J. Silenko, O. V. Teryaev

We study the possibility of experimental testing the manifestations of equivalence principle in spin-gravity interactions. We reconsider the earlier experimental data and get the first experimental bound on anomalous gravitomagnetic moment. The spin coupling to the Earth&#39;s rotation may also be explored at the extensions of neutron EDM and g-2 experiments

Kh. S. Nirov, A. V. Razumov

A Toda equation is specified by a choice of a Lie group and a $\mathbb Z$-gradation of its Lie algebra. The Toda equations associated with loop groups of complex classical Lie groups, whose Lie algebras are endowed with integrable $\mathbb Z$-gradations with finite dimensional grading subspaces, are described in an explicit form.

Yehonatan Elon, Sven Gnutzmann, Christian Joas, Uzy Smilansky

In an attempt to characterize the distribution of forms and shapes of nodal domains in wave functions, we define a geometric parameter - the ratio $ρ$ between the area of a domain and its perimeter, measured in units of the wavelength $1/\sqrt{E}$. We show that the distribution function $P(ρ)$ can distinguish between domains in which the classical dynamics i

Abolfazl Bayat, Vahid Karimipour

We generalize an already proposed protocol for quantum state transfer to spin chains of arbitrary spin. An arbitrary unknown $d-$ level state is transferred through a chain with rather good fidelity by the natural dynamics of the chain. We compare the performance of this protocol for various values of $d$. A by-product of our study is a much simpler method f

Andrea Nahmod, Jalal Shatah, Luis Vega, Chongchun Zeng

In this paper we establish the equivalence of solutions between Schrödinger map into $\mathbb{S}^2$ or $ \mathbb{H}^2$ and their associated gauge invariant Schrödinger equations. We also establish the existence of global weak solutions into $\mathbb{H}^2$ in two space dimensions. We extend these ideas for maps into compact hermitian symmetric manifolds with

S. N. Gninenko, N. V. Krasnikov, A. Rubbia

It has been recently suggested that the vacuum magnetic dichroism observed by the PVLAS experiment could be explained by the pair production of a new light, m ~0.1 eV, millicharged, q ~ 3 10^{-6} e, fermions. In addition, it has been pointed out that millicharged particles with q > 10^{-9} e appear naturally in models based on the string theory. We show that

H. Iida, H. Suganuma, T. T. Takahashi

Light scalar-quarks ϕ(colored scalar particles or idealized diquarks) and their color-singlet hadronic states are studied with quenched SU(3)_c lattice QCD in terms of mass generation. We investigate ``scalar-quark mesons&#39;&#39; ϕ^\dagger ϕand ``scalar-quark baryons&#39;&#39; ϕϕϕas the bound states of scalar-quarks ϕ. We also investigate the bound states

Vladimir Dzhunushaliev

The model of Dark Matter is proposed in which the Dark Matter is a classical color field. The color fields are invisible as they may interact with colored elementary particles like &#39;t Hooft - Polyakov monopole only. The comparison with the Universal Rotation Curve is carried out.

Jennifer James, Thomas Koberda, Kathryn Lindsey, Cesar E. Silva

We introduce the notion of measurable sensitivity, a measure-theoretic version of the condition of sensitive dependence on initial conditions. It is a consequence of light mixing, implies a transformation has only finitely many eigenvalues, and does not exist in the infinite measure-preserving case. Unlike the traditional notion of sensitive dependence, meas

M. Mohammadi, M. H. Naderi, M. Soltanolkotabi

In this paper, we study the dissipative dynamics of the Jaynes-Cummings model with phase damping in the presence of a classical homogeneous gravitational field. The model consists of a moving two-level atom simultaneously exposed to the gravitational field and a single-mode traveling radiation field in the presence of the phase damping. We present a quantum

Z. G. Huang, Q. Q. Sun, W. Fang, H. Q. Lu

In this paper, we regard dilaton in Weyl-scaled induced gravitational theory as coupled Quintessence, which is called DCQ model by us. Parametrization of the dark energy model is a good method by which we can construct the scalar potential directly from the effective equation of state function $ω_σ(z)$ describing the properties of the dark energy. Applying t

Johan Aberg

Measures are introduced to quantify the degree of superposition in mixed states with respect to orthogonal decompositions of the Hilbert space of a quantum system. These superposition measures can be regarded as analogues to entanglement measures, but can also be put in a more direct relation to the latter. By a second quantization of the system it is possib

H. T. Cui, K. Li, X. X. Yi

The dynamics of entanglement and the phenomenon of entanglement sudden death (ESD) \cite{yu} are discussed in bipartite systems, measured by Wootters Concurrence. Our calculation shows that ESD appears whenever the system is open or closed and is dependent on the initial condition. The relation of the evolution of entanglement and energy transfer between the

Eduardo D. Sontag

This paper (parts I and II) provides an expository introduction to monotone and near-monotone dynamical systems associated to biochemical networks, those whose graphs are consistent or near-consistent. Many conclusions can be drawn from signed network structure, associated to purely stoichiometric information and ignoring fluxes. In particular, monotone syst