October 2005 arXiv papers — page 9

Edward Barry, Zach Hensel, Michael Shribak, Rudolf Oldenbourg

We study the liquid crystalline phase behavior of a concentrated suspension of helical flagella isolated from {\it Salmonella typhimurium}. Flagella are prepared with different polymorphic states, some of which have a pronounced helical character while others assume a rod-like shape. We show that the static phase behavior and dynamics of chiral helices are v

S. I. Vedeneev, D. K. Maude

Break-junction tunneling spectroscopy at temperatures 30-50 mK in high magnetic field is used to directly probe the quasiparticle density of states within the energy gap in a single crystal Bi2212 high-$T_c$ superconductor. The measured tunneling conductances $dI/dV(V)$ in the subgap region have a zero flat region with no evidence for a linear increase of th

A. Amo, M. D. Martin, L. Vina, A. I. Toropov

We present a systematic study of the exciton/electron-hole plasma photoluminescence dynamics in bulk GaAs for various lattice temperatures and excitation densities. The competition between the exciton and electron-hole pair recombination dominates the onset of the luminescence. We show that the metal-to-insulator transition, induced by temperature and/or exc

Dwaipayan Chakrabarti, Biman Bagchi

A significant deviation from the Debye model of rotational diffusion in the dynamics of orientational degrees of freedom in an equimolar mixture of ellipsoids of revolution and spheres is found to begin precisely at a temperature at which the average inherent structure energy of the system starts falling with drop in temperature. We argue that this onset tem

Jean-Philippe Michel, Emmanuelle Lacaze, Michel Goldmann, Marc Gailhanou

We study the structure of very thin liquid crystal films frustrated by antagonistic anchorings in the smectic phase. In a cylindrical geometry, the structure is dominated by the defects for film thicknesses smaller than 150 nm and the detailed topology of the defects cores can be revealed by x-ray diffraction. They appear to be split in half tube-shaped Rota

T. Kimura, J. C. Lashley, A. P. Ramirez

Magnetoelectric and magnetoelastic phenomena correlated with a phase transition into noncollinear magnetic phase have been investigated for single crystals of CuFeO2 with a frustrated triangular lattice. CuFeO2 exhibits several long-wavelength magnetic structures related to the spin frustration, and it is found that finite electric polarization, namely inver

A. Majka, W. Wislicki

Choice models for populations of agents on graphs are studied in terms of statistical thermodynamics. Equations of state are derived and discussed for different connectivity schemes, utility approximations, and temperature and volume regimes. Analogies to ideal classical and quantum gases are found and features specific for network systems are discussed.

S. Picozzi, A. Continenza, M. Kim, A. J. Freeman

The magneto-optical properties of Ga$_{1-x}$Mn$_{x}$As including their most common defects were investigated with precise first--principles density-functional FLAPW calculations in order to: {\em i}) elucidate the origin of the features in the Kerr spectra in terms of the underlying electronic structure; {\em ii}) perform an accurate comparison with experime

H. J. H. Smilde, A. A. Golubov, Ariando, G. Rijnders

We report on an \textit{ab}-anisotropy of $J_{c \parallel b}/J_{c \parallel a}% \cong 1.8$ and $I_{c}R_{n \parallel b}/I_{c}R_{n \parallel a}\cong 1.2$ in ramp-edge junctions between untwinned YBa$_{2}$Cu$_{3}$O$_{7}$ and $s$% -wave Nb. For these junctions, the angle $θ$ with the YBa$_{2}$Cu$_{3}$O$_{7}$ crystal b-axis is varied as a single parameter. The $R

Maxim Mostovoy

It was recently observed that materials showing most striking multiferroic phenomena are frustrated spin-density-wave magnets. We present a simple phenomenological theory, which describes the orientation of the induced electric polarization for various incommensurate magnetic states, its dependence on temperature and magnetic field, and anomalies of dielectr

T. Lancaster, S. J. Blundell, M. L. Brooks, P. J. Baker

We present the first evidence of magnetic order in the quasi-one-dimensional spin 1/2 molecular chain compound, copper pyrazine dinitrate Cu(C4H4N2)(NO3)2}. Zero field muon-spin relaxation measurements made at dilution refrigerator temperatures show oscillations in the measured asymmetry, characteristic of a quasistatic magnetic field at the muon sites. Our

R. J. Baxter

The chiral Potts model continues to pose particular challenges in statistical mechanics: it is ``exactly solvable'' in the sense that it satisfies the Yang-Baxter relation, but actually obtaining the solution is not easy. Its free energy was calculated in 1988 and the order parameter was conjectured in full generality a year later. However, a derivat

Zhongzhi Zhang, Lili Rong, Francesc Comellas

We introduce a minimal extended evolving model for small-world networks which is controlled by a parameter. In this model the network growth is determined by the attachment of new nodes to already existing nodes that are geographically close. We analyze several topological properties for our model both analytically and by numerical simulations. The resulting

Huijie Yang, Fangcui Zhao, Yunpeng Wang, Binghong Wang

Structure-induced features of the wave functions for the quantum systems on complex networks are discussed in this paper. For a quantum system on a network, the state corresponding to the eigenvalue close to the center of the spectrum is used as the representative state to display the impacts of the structure on the wave functions. We consider the Erdos-Reny

W. Q. Chen, Z. Y. Weng, D. N. Sheng

We present a numerical study of the spin Hall effect in a two-dimensional hole gas (2DHG) system in the presence of disorder. We find that the spin Hall conductance (SHC), extrapolated to the thermodynamic limit, remains finite in a wide range of disorder strengths for a closed system on torus. But there is no intrinsic spin Hall accumulation as induced by a

K. Yu. Bliokh

We consider the semiclassical equations of motion of a particle when both an external electromagnetic field and the Berry gauge field in the momentum space are present. It is shown that these equations are Hamiltonian and relations between the canonical and covariant variables are determined through a consistent account of all components of the Berry connect

H. Jirari, W. Potz

The interaction of a quantum system with a bath, usually referred to as dissipation, can be controlled if one can establish quantum interference between the system--bath interaction and a coupling of the system to an external control field. This is demonstrated for the example of the spin-boson model in the strong coupling limit for the system--bath interact

M. Martinez-Mares, E. Castano

We study the effect of left-right symmetry on the distribution of the parametric derivative of the dimensionless conductance T with respect to an external parameter X, dT/dX, of ballistic chaotic cavities with two leads, each supporting N propagating modes. We show that T and dT/dX are uncorrelated for any N. For N=1 we calculate the distribution of dT/dX in

S. J. Thompson, A. P. Doel, R. G. Bingham, A. Charalambous

Described here is the design and commissioning of a coronagraph facility for the 4.2 metre William Herschel Telescope (WHT) and its Nasmyth Adaptive Optics system for Multi-purpose Instrumentation (NAOMI). The use of the NAOMI system gives an improved image resolution of ~0.15 arcsecs at a wavelength of 2.2um. This enables the Optimised Stellar Coronagraph f

Mitsuru Honda, Yasuko S. Honda

We expand the off-resonant scattering theory for particle diffusion in magnetized current filaments that can be typically compared to astrophysical jets, including active galactic nucleus jets. In a high plasma beta region where the directional bulk flow is a free-energy source for establishing turbulent magnetic fields via current filamentation instabilitie

D. L. Ferreiro, M. G. Pastoriza, M. C. Rickes

We present in this paper a list of candidates tidal dwarf galaxies selected among a sample of 117 HII region observed in 11 minor mergers. The classification of the HII regions was performed using the blue absolute magnitude (M$_B$ $<$ -15), H$α$ luminosity ($\cal L$$(Hα)$ $>$ 10$^{39}$ erg s$^{-1}$) and the star formation rate ($SFR_{Hα}$ $>$ 0.4 M$_{\odot}

Michael A. Beasley, Jay Strader, Jean P. Brodie, A. Javier Cenarro

We have analysed the globular cluster (GC) system of the nucleated dwarf elliptical galaxy VCC 1087 in the Virgo cluster, based on Keck/LRIS spectroscopy and archival HST/ACS imaging. We estimate VCC 1087 hosts a total population of 77+/-19 GCs, which corresponds to a relatively high V-band specific frequency of 5.8+/-1.4. The g-z color distribution of the G

A. J. Blustin, W. B. Landsman, M. Still, S. R. Rosen

The wide range of UV extinction properties in the Small Magellanic Cloud (SMC) probably traces the effects of star formation on interstellar dust. The Swift UVOT, with its three UV filters (centred at 1800, 2200 and 2500 A respectively) and three optical filters, is an ideal instrument to map this extinction. We present preliminary results of six-band photom

A. J. Blustin, S. V. Fuerst, G. Branduardi-Raymont, M. J. Page

We apply Principal Component Analysis (PCA) to study the variability of the X-ray continuum in the Seyfert 1 galaxy NGC 7469. The PCA technique is used to separate out linear components contributing to variability between multiple datasets; the technique is often used in analysis of optical spectra, but has rarely been applied to AGN X-ray spectroscopy. Runn

Sylvaine Turck Chieze, Pierre Henri Carton, Jerome Ballot, Jean Christophe Barriere

The GOLFNG (Global Oscillations at Low Frequency New Generation) instrument is devoted to the search for solar gravity and acoustic modes, and also chromospheric modes from space. This instrument which is a successor to GOLF/SOHO will contribute to improve our knowledge of the dynamics of the solar radiative zone. It is a 15 points resonant scattering spectr

C. Wolf

We report the discovery of an ultra-cool white dwarf in the COMBO-17 survey. So far, only seven objects have been discovered in this rare category of white dwarfs, which are characterized by strong flux depression in the far-red and near-infrared part of the spectrum, presumably due to collisionally induced absorption (CIA). The new object COMBO-17 J114356.0

Andrei Gruzinov

We formulate variation principle for force-free magnetosphere of an inclined pulsar: ${\cal E} +{\bf Ω}\cdot {\bf M}$ ($\cal E$, ${\bf M}$ are electromagnetic energy and angular momentum, ${\bf Ω}$ is the angular velocity of a star) is stationary under isotopological variations of magnetic field and arbitrary variations of electric field. The variation princ

D. Vogt, P. S. Letelier

We analyze the presence of an additional singular thin disk in the recent General Relativistic model of galactic gravitational field proposed by Cooperstock and Tieu. The physical variables of the disk&#39;s energy-momentum tensor are calculated. We show that the disk is made of exotic matter, either cosmic strings or struts with negative energy density.

Jan-Uwe Ness, Juergen H. M. M. Schmitt

The cTTS TW Hya has been observed with high-resolution X-ray spectrometers. Previously found high densities inferred from He-like f/i triplets strongly suggested the detected X-ray emission to be dominated by an accretion shock. Because of their radiation field dependence He-like f/i ratios do not provide unambiguous density diagnostics. Here we present addi

W. H. de Vries, R. H. Becker, R. L. White

We have combined a sample of 44984 quasars, selected from the Sloan Digital Sky Survey (SDSS) Data Release 3, with the FIRST radio survey. Using a novel technique where the optical quasar position is matched to the complete radio environment within 450&#34;, we are able to characterize the radio morphological make-up of what is essentially an optically selec

Eric L. Sandquist

We examine the blue straggler populations of 13 low-luminosity (M_V_t >~ -6) globular clusters and 2 old open clusters. These clusters test blue straggler formation in environments intermediate between higher luminosity (and usually higher density) clusters and the Galactic field. The anti-correlation between the relative frequency of blue stragglers (F_BSS

A. Pietarila, H. Socas-Navarro, T. Bogdan, M. Carlsson

The Ca II infrared triplet around 8540 A is a good candidate for observing chromospheric magnetism. We show results from combining a radiation hydrodynamic simulation with a Stokes synthesis code. The simulation shows interesting time-varying behavior of the Stokes V profiles as waves propagate through the lines&#39; formation regions. Disappearing and reapp

Aravind Natarajan, Pierre Sikivie

We prove that a flow of cold collisionless particles from all directions in and out of a region necessarily forms a caustic. A corollary is that, in cold dark matter cosmology, galactic halos have inner caustics in addition to the more obvious outer caustics. The outer caustics are fold catastrophes located on topological spheres surrounding the galaxy. To o

Shigenobu Hirose, Julian H. Krolik, James M. Stone

(shortened) We calculate the vertical structure of a local patch of an accretion disk in which heating by dissipation of MRI-driven MHD turbulence is balanced by radiative cooling. Heating, radiative transport, and cooling are computed self-consistently with the structure by solving the equations of radiation MHD in the shearing-box approximation. Using a fu

R. Centeno, H. Socas-Navarro, M. Collados, J. Trujillo Bueno

Novel spectro-polarimetric observations of the \ion{He}{1} multiplet are used to explore the dynamics of the chromospheric oscillation above sunspot umbrae. The results presented here provide strong evidence in support of the two-component model proposed by Socas-Navarro and co-authors. According to this model, the waves propagate only inside channels of sub

N. J. Dunstone, J. R. Barnes, A. Collier Cameron, M. Jardine

We present new observations of the prominence system on the K3 dwarf Speedy Mic (BO Mic, HD 197890). Using an improved technique to track the absorption features in H_alpha we find a very active prominence system with approximately ten prominences on the observable hemisphere per rotation. From a total of 25 prominences we find an average axial distance of 2

A. Rest, N. B. Suntzeff, K. Olsen, J. L. Prieto

In principle, the light from historical supernovae could still be visible as scattered-light echoes even centuries later. However, while echoes have been discovered around some nearby extragalactic supernovae well after the explosion, targeted searches have not recovered any echoes in the regions of historical Galactic supernovae. The discovery of echoes can

Yuichiro Ezoe, Motohide Kokubun, Kazuo Makishima, Yutaro Sekimoto

Chandra ACIS-I data of the molecular cloud and HII region complex NGC 6334 were analyzed. The hard X-ray clumps detected with ASCA (Sekimoto et al. 2000) were resolved into 792 point sources. After removing the point sources, an extended X-ray emission component was detected over a 5x9 pc2 region, with the 0.5-8 keV absorption-corrected luminosity of 2x10^33

A. Domiciano de Souza, T. Driebe, O. Chesneau, K. -H. Hofmann

We present the first spectro-interferometric observations of the circumstellar envelope (CSE) of a B[e] supergiant (CPD -57 2874), performed with the Very Large Telescope Interferometer (VLTI) using the beam-combiner instruments AMBER (near-IR interferometry with three 8.3 m Unit Telescopes or UTs) and MIDI (mid-IR interferometry with two UTs). Our observati

A. Domiciano de Souza, T. Driebe, O. Chesneau, K. -H. Hofmann

We present the first high spatial and spectral observations of the circumstellar envelope (CSE) of a B[e] supergiant (CPD$-57 2874$), performed with the Very Large Telescope Interferometer (VLTI). Spectra, visibilities, and closure phase, were obtained using the beam-combiner instruments AMBER (near-IR interferometry with three 8.3 m Unit Telescopes or UTs)

F. Fraternali, T. Oosterloo, J. J. Binney, R. Sancisi

The study of gas outside the plane of disc galaxies is crucial to understanding the circulation of material within a galaxy and between galaxies and the intergalactic environment. We present new HI observations of the edge-on galaxy NGC891, which show an extended halo component lagging behind the disc in rotation. We compare these results for NGC891 with oth

M. Villar-Martin, S. F. Sanchez, C. De Breuck, R. Peletier

We present: 1) a kinematic and morphological study of the giant Lya nebula associated with the radio galaxy MRC2104-242 (z = 2.49) based on integral field spectroscopic VIMOS data from VLT; 2) a photometric study of the host (proto?) galaxy based on Spitzer Space Telescope data. The galaxy appears to be embedded in a giant (>120 kpc) gas reservoir that surro

Stefano Bianchi, Matteo Guainazzi, Marco Chiaberge

We present a sample of 8 Seyfert 2 galaxies observed by HST, Chandra and XMM-Newton. All of the sources present soft X-ray emission which is coincident in extension and overall morphology with the [OIII] emission. The spectral analysis reveals that the soft X-ray emission of all the objects is likely to be dominated by a photoionized gas. We tested with the

Douglas Scott

The Standard Model of Particle Physics (SMPP) is an enormously successful description of high energy physics, driving ever more precise measurements to find &#34;physics beyond the standard model&#34;, as well as providing motivation for developing more fundamental ideas that might explain the values of its parameters. Simultaneously, a description of the en

Tomohiro Kato, Masaaki Kusunose, Fumio Takahara

H1426+428 is one of blazars that are observed by $γ$-rays in the TeV region. Because TeV $γ$-rays from distant sources are subject to attenuation by the extragalactic background light (EBL) via electron-positron pair production, the intrinsic spectrum of the TeV $γ$-rays should be inferred by using the models of radiation processes and EBL spectrum. We set c

J. A. de Freitas Pacheco, T. Regimbau, S. Vincent, A. Spallicci

The coalescence rate of two neutron stars (NS) is revisited. For estimation of the number of bound NS-NS and the probability of their coalescence in a timescale $τ$, the galactic star formation history, directly derived from observations, and the evolution of massive stars are considered. The newly established galactic merging rate is $(1.7\pm 1.0) \times 10

Luis P. Chimento, Mónica Forte

We investigate a Bianchi type-I (BTI) cosmology with k essence and find the set of models which dissipate the initial anisotropy. There are cosmological models with extended tachyon fields and k essence having constant bariotropic index. We obtain the conditions leading to a regular bounce of the average geometry and the residual anisotropy on the bounce. Fo

Paramita Barai, Paul J. Wiita

We seek to develop an essentially analytical model for the evolution of Fanaroff-Riley Class II radio galaxies as they age individually and as their numbers vary with cosmological epoch. Such modeling is required in order to probe in more detail the impact of radio galaxies on the growth of structures in the universe, which appears likely to have been quite

Craig E. Maloney, Anaël Lemaître

We present results on a series of 2D atomistic computer simulations of amorphous systems subjected to simple shear in the athermal, quasistatic limit. The athermal quasistatic trajectories are shown to separate into smooth, reversible elastic branches which are intermittently broken by discrete catastrophic plastic events. The onset of a typical plastic even

Ilya Selyuzhenkov

We present results on the parity violation effects and global system polarization measurements in Au+Au collisions at sqrt(s_NN) = 62 GeV obtained with the STAR detector at RHIC. The parity violation effects are studied by three particle azimuthal correlations of charged particles. The global polarization of the system is examined by measuring the polarizati

Frank Marsiglio

In the conventional BCS description of a superconductor the kinetic energy increases in the superconducting state. We describe the observed decrease in kinetic energy by adopting a simple model of electrons whose elastic scattering rate undergoes a sharp decrease as the temperature is lowered below Tc. This phenomenology has been suggested by other experimen

A. Riffeser, J. Fliri, S. Seitz, R. Bender

We present a comprehensive treatment of the pixel-lensing theory and apply it to lensing experiments and their results toward M31. Using distribution functions for the distances, velocities, masses, and luminosities of stars, we derive lensing event rates as a function of the event observables. In contrast to the microlensing regime, in the pixel-lensing reg

Howard Baer, Stefano Profumo

Low energy antideuterons suffer a very low secondary and tertiary astrophysical background, while they can be abundantly synthesized in dark matter pair annihilations, therefore providing a privileged indirect dark matter detection technique. The recent publication of the first upper limit on the low energy antideuteron flux by the BESS collaboration, a new

Zhenhua Yu, Gordon Baym

The spin response functions measured in multi-component fermion gases by means of rf transitions between hyperfine states are strongly constrained by the symmetry of the interatomic interactions. Such constraints are reflected in the spin f-sum rule that the response functions must obey. In particular, only if the effective interactions are not fully invaria

Ulrike Draeger, Michel Prévot, Thierry Poidras, Janna Riisager

Tiny basaltic samples containing finely grained titanomagnetite with Curie temperature less than 100 C were heated in air in weak field (25 to 100microT) at temperatures between 400 and 560 C for times as long as 32 hours. Oxyexsolution of titanomagnetite resulted in the crystallization of interacting single domain particles with Curie point close to 540 C a

Krzysztof Belczynski, Matthew Benacquista, Shane L. Larson, Ashley J. Ruiter

Compact object binaries, mostly double with dwarfs, are believed to be a potential source of confusion-limited noise for the Laser Interferometer Space Antenna (LISA). In a specific frequency range, this noise may rise above the instrumental noise sources and hence hinder detection of other types of signals, e.g. extreme mass ratio inspirals of stellar mass

W. Huang, D. R. Gies

We derive the effective temperatures and gravities of 461 OB stars in 19 young clusters by fitting the H-gamma profile in their spectra. We use synthetic model profiles for rotating stars to develop a method to estimate the polar gravity for these stars, which we argue is a useful indicator of their evolutionary status. We combine these results with projecte

Mauricio Bellini

Using a formalism recently introduced we study the decaying of the cosmological parameter during the early evolution of an universe, whose evolution is governed by a vacuum equation of state. We use a stochastic approach in a nonperturbative treatment of the inflaton field from a Noncompact Kaluza-Klein (NKK) theory, to study the evolution of energy density

Kazuo Habiro, Jean-Baptiste Meilhan

A link L in the 3-sphere is called Brunnian if every proper sublink of L is trivial. In a previous paper, the first author proved that the restriction to Brunnian links of any Goussarov-Vassiliev finite type invariant of (n+1)-component links of degree<2n is trivial. The purpose of this paper is to study the first nontrivial case. We will show that the restr

Alejandro Corichi, Jeronimo Cortez, Guillermo A. Mena Marugan

Recent results on the non-unitary character of quantum time evolution in the family of Gowdy T**3 spacetimes bring the question of whether one should renounce in cosmology to the most sacred principle of unitary evolution. In this work we show that the answer is in the negative. We put forward a full nonperturbative canonical quantization of the polarized Go

M. C. Rodriguez

We consider the minimal supersymmetric extension of the 3-3-1 model and we study the mass spectra in the scalar sector of this model without the anti-sextet. We show that all our lighest scalars are in agreement with the experimental limits.

Claudio Coriano&#39;, Nikos Irges, Elias Kiritsis

The effective field theory of the minimal Low Scale Orientifold Models is developed. It describes universal features of related orientifold vacua in string theory. It contains, beyond the Standard Model fields, an MSSM-like Higgs sector and three anomalous (massive) U(1) gauge bosons. All renormalizable couplings are included as well as some dimension-five c

J. Levinsen, V. Gurarie

We study a gas of fermions undergoing a wide resonance s-wave BCS-BEC crossover, in the BEC regime at zero temperature. We calculate the chemical potential and the speed of sound of this Bose-condensed gas, as well as the condensate depletion, in the low density approximation. We discuss how higher order terms in the low density expansion can be constructed.

Maxim Braverman, Thomas Kappeler

We construct a canonical element, called the refined analytic torsion, of the determinant line of the cohomology of a closed oriented odd-dimensional manifold M with coefficients in a flat complex vector bundle E. We compute the Ray-Singer norm of the refined analytic torsion. In particular, if there exists a flat Hermitian metric on E, we show that this nor

K. A. Bronnikov, S. G. Rubin

We show that the problem of stabilization of extra dimensions in Kaluza-Klein type cosmology may be solved in a theory of gravity involving high-order curvature invariants. The method suggested (employing a slow-change approximation) can work with rather a general form of the gravitational action. As examples, we consider pure gravity with Lagrangians quadra

Ladislav Mišta

In standard coherent state teleportation with shared two-mode squeezed vacuum (TMSV) state there is a trade-off between the teleportation fidelity and the fidelity of estimation of the teleported state from results of the Bell measurement. Within the class of Gaussian operations this trade-off is optimal, i.e. there is not a Gaussian operation which would gi

Michael A. Lomholt

A study is made of how active membrane proteins can modify the long wavelength mechanics of fluid membranes. The activity of the proteins is modelled as disturbing the protein surroundings through non-local force distributions of which a force-dipole distribution is the simplest example. An analytic expression describing how the activity modifies the force-b

Ll. Masanes

We consider entanglement distillation from a single-copy of a multipartite state, and instead of rates we analyze the &#34;quality&#34; of the distilled entanglement. This &#34;quality&#34; is quantified by the fidelity with the GHZ-state. We show that each not fully-separable state $σ$ can increase the &#34;quality&#34; of the entanglement distilled from ot

Ulrik L. Andersen, Metin Sabuncu, Radim Filip, Gerd Leuchs

We investigate the optimal tradeoff between information gained about an unknown coherent state and the state disturbance caused by the measurement process. We propose several optical schemes that can enable this task, and we implement one of them, a scheme which relies on only linear optics and homodyne detection. Experimentally we reach near optimal perform

S. Yang, Z. Song, C. P. Sun

We theoretically design and analytically study a controllable beam splitter for the spin wave propagating in a star-shaped (e.g., a $Y$-shaped beam) spin network. Such a solid state beam splitter can display quantum interference and quantum entanglement by the well-aimed controls of interaction on nodes. It will enable an elementary interferometric device fo

Yongjin Jiang

We study theoretically the current-induced spin polarization effect in a two-terminal mesoscopic structure which is composed of a semiconductor two-dimensional electron gas (2DEG) bar with Rashba spin-orbit (SO) interaction and two attached ideal leads. The nonequilibrium spin density is calculated by solving the scattering wave functions explicitly within t

Lorenzo Iorio, Giuseppe Giudice

The multidimensional braneworld gravity model by Dvali, Gabadadze and Porrati was primarily put forth to explain the observed acceleration of the expansion of the Universe without resorting to dark energy. One of the most intriguing features of such a model is that it also predicts small effects on the orbital motion of test particles which could be tested i

Xiao-Jun Bi

High resolution simulations reveal that in the cold dark matter scenario the structures form hierarchically and a large number of substructures survive in the galactic halos. The substructures can be probed if they emit gamma rays via dark matter annihilation. We calculated the gamma ray fluxes from the dark matter annihilations in the substructures of our G

Pierluigi Contucci, Cristian Giardina, Claudio Giberti, Cecilia Vernia

We study the relative fluctuations of the link overlap and the square standard overlap in the three dimensional Gaussian Edwards-Anderson model with zero external field. We first analyze the correlation coefficient and find that the two quantities are uncorrelated above the critical temperature. Below the critical temperature we find that the link overlap ha

Eva Miranda, Nguyen Tien Zung

We prove an equivariant version of the local splitting theorem for tame Poisson structures and Poisson actions of compact Lie groups. As a consequence, we obtain an equivariant linearization result for Poisson structures whose transverse structure has semisimple linear part of compact type.

Wei Jiang, Qun-feng Chen, Yong-sheng Zhang, G. -C. Guo

The influence of a repump laser on a nearly degenerate four-wave-mixing (NDFWM) spectrum was investigated. We found the amplitude and line shape of the NDFWM depended strongly on the detuning of the repump field. A five-peak structure was observed. And at some certain repump detuning a dip appeared at the central peak. A rough analysis was proposed to explai

C. P. Burgess, C. Escoda, F. Quevedo

Recent progress in understanding modulus stabilization in string theory relies on the existence of a non-renormalization theorem for the 4D compactifications of Type IIB supergravity which preserve N=1 supersymmetry. We provide a simple proof of this non-renormalization theorem for a broad class of Type IIB vacua using the known symmetries of these compactif

C. Y. Sun, D. H. Zhang

Using the &#34;$δN$-formalism&#34;, We obtain the expression of the non-Gaussianity of multiple-field inflationary models with the nontrivial field-space metric. Further, we rewritten the result by using the slow-rolling approximation.

Valery P. Dmitriyev

The shortening of bodies in the direction of motion, Lorentz contraction, follows from the solution of Maxwell&#39;s equations. Moving light clocks will tick slower than those at rest because the speed of light does not depend on a source of the light. The latter and Lorentz contraction imply the relativistic time dilation. The invariance of the light speed

Hiromi Otsuka, Yutaka Okabe, Kouichi Okunishi

The field-induced Berezinskii-Kosterlitz-Thouless (BKT) transition in the ground state of the triangular antiferromagnetic Ising model is studied by the level-spectroscopy method. We analyze dimensions of operators around the BKT line, and estimate the BKT point $H_{\rm c}\simeq0.5229\pm0.001$, which is followed by a level-consistency check to demonstrate th

William Kung, M. Cristina Marchetti, Karl Saunders

Starting from a microscopic definition of an alignment vector proportional to the polarization, we discuss the hydrodynamics of polar liquid crystals with local $C_{\infty v}$-symmetry. The free energy for polar liquid crystals differs from that of nematic liquid crystals ($D_{\infty h}$) in that it contains terms violating the ${\bf{n}}\to -{\bf{n}}$ symmet

XuanLong Nguyen, Martin J. Wainwright, Michael I. Jordan

The goal of binary classification is to estimate a discriminant function $γ$ from observations of covariate vectors and corresponding binary labels. We consider an elaboration of this problem in which the covariates are not available directly but are transformed by a dimensionality-reducing quantizer $Q$. We present conditions on loss functions such that emp

R. Foot

We re-analyse the implications of the DAMA/NaI experiment for mirror matter-type dark matter, taking into account information from the energy dependence of the DAMA annual modulation signal. This is combined with the null results from the CDMS experiment, leading to fairly well defined allowed regions of parameter space. The allowed regions of parameter spac

L. C. Gallo

We present two XMM-Newton observations of the luminous (L_x > 10^46 erg/s), radio-quiet quasar, PG 1407+265, separated by eleven months. The data indicate two distinct states: a highly variable, bright state (first epoch); and a quiescent, low-flux one (second epoch). During the low-flux state the spectrum is consistent with a single, unabsorbed power law. H

T. Gopinath, Ranabir Das, Anil Kumar

In this paper a programmable quantum state discriminator is implemented by using nuclear magnetic resonance. We use a two qubit spin-1/2 system, one for the data qubit and one for the ancilla (programme) qubit. This device does the unambiguous (error free) discrimination of pair of states of the data qubit that are symmetrically located about a fixed state.

R. Friedberg, T. D. Lee, W. Q. Zhao

We present an explicit convergent iterative solution for the lowest energy state of the Schroedinger equation with an $N$-dimensional radial potential $V=\frac{g^2}{2}(r^2-1)^2$ and an angular momentum $l$. For $g$ large, the rate of convergence is similar to a power series in $g^{-1}$.

C. E. Roman-Velazquez, C. Noguez

The role of geometry on dispersive forces is investigated by calculating the energy between different spheroidal particles and planar surfaces, both with arbitrary dielectric properties. The energy is obtained in the non-retarded limit using a spectral representation formalism and calculating the interaction between the surface plasmons of the two macroscopi

H. L. Huang, L. H. Cheng, X. X. Yi

We extend the idea of entanglement concentration for pure states(Phys. Rev. Lett. {\bf 88}, 187903) to the case of mixed states. The scheme works only with particle statistics and local operations, without the need of any other interactions. We show that the maximally entangled state can be distilled out when the initial state is pure, otherwise the entangle

Andrew M. Childs, Pawel Wocjan

We consider an approach to deciding isomorphism of rigid n-vertex graphs (and related isomorphism problems) by solving a nonabelian hidden shift problem on a quantum computer using the standard method. Such an approach is arguably more natural than viewing the problem as a hidden subgroup problem. We prove that the hidden shift approach to rigid graph isomor

Andrew D. Greentree, Simon J. Devitt, Lloyd C. L. Hollenberg

The importance of transporting quantum information and entanglement with high fidelity cannot be overemphasized. We present a scheme based on adiabatic passage that allows for transportation of a qubit, operator measurements and entanglement, using a 1-D array of quantum sites with a single sender (Alice) and multiple receivers (Bobs). Alice need not know wh

Gabriel A. Durkin, Christoph Simon

We introduce inequalities for multi-partite entanglement, derived from the geometry of spin vectors. The criteria are constructed iteratively from cross and dot products between the spins of individual subsystems, each of which may have arbitrary dimension. For qubit ensembles the maximum violation for our inequalities is larger than that for the Mermin-Klys

Marc Timme, Theo Geisel, Fred Wolf

We analyze the dynamics of networks of spiking neural oscillators. First, we present an exact linear stability theory of the synchronous state for networks of arbitrary connectivity. For general neuron rise functions, stability is determined by multiple operators, for which standard analysis is not suitable. We describe a general non-standard solution to the

S. M. Abrarov, T. W. Kim, T. W. Kang

We consider two equations for the filling factor estimation of infiltrated zinc oxide (ZnO) in silica (SiO_2) opal and gallium nitride in ZnO opal. The first equation is based on the effective medium approximation, while the second one - on Maxwell-Garnett approximation. The comparison between two filling factors shows that both equations can be equally used

C. Foudas, R. Bainbridge, D. Ballard, I. Church

The Front End Driver, FED, is a 9U 400mm VME64x card designed for reading out the Compact Muon Solenoid, CMS, silicon tracker signals transmitted by the APV25 analogue pipeline Application Specific Integrated Circuits. The FED receives the signals via 96 optical fibers at a total input rate of 3.4 GB/sec. The signals are digitized and processed by applying a

J. Jones, G. Hall, C. Foudas, A. Rose

We report on preliminary design studies of a pixel detector for CMS at the Super-LHC. The goal of these studies was to investigate the possibility of designing an inner tracker pixel detector whose data could be used for selecting events at the First Level Trigger. The detector considered consists of two layers of 20x50x10 um3 pixels at very close radial pro

C. Foudas, A. Rose, J. Jones, G. Hall

It is expected that the LHC accelerator and experiments will undergo a luminosity upgrade which will commence after several years of running. This part of the LHC operations is referred to as Super-LHC (SLHC) and is expected to provide beams of an order of magnitude larger luminosity (1035cm-2sec-1) than the current design. Preliminary results are presented

Francois Henault

This paper presents the basic principle and theoretical relationships of an original method allowing to retrieve the Wavefront Errors (WFE) of a ground or space-borne telescope when combining its main pupil with a second, decentered reference optical arm. The measurement accuracy of such a &#34;telescope-interferometer&#34; is then estimated by means of vari

Francois Henault

The use of Wavefront Sensors (WFS) is nowadays fundamental in the field of instrumental optics. This paper discusses the principle of an original and recently proposed new class of WFS. Their principle consists in evaluating the slopes of the wavefront errors by means of varying density filters placed into the image plane of the tested optical system. The de

I. I. Tupitsyn, A. V. Volotka, D. A. Glazov, V. M. Shabaev

The magnetic-dipole transition probabilities between the fine-structure levels (1s^2 2s^2 2p) ^2P_1/2 - ^2P_3/2 for B-like ions and (1s^2 2s 2p) ^3P_1 - ^3P_2 for Be-like ions are calculated. The configuration-interaction method in the Dirac-Fock-Sturm basis is employed for the evaluation of the interelectronic-interaction correction with negative-continuum

Yaroslav V. Kartashov, Victor A. Vysloukh, Lluis Torner

We put forward properties of solitons supported by optical lattices featuring topological dislocations, and show that solitons experience attractive and repulsive forces around the dislocations. Suitable arrangements of dislocations are even found to form soliton traps, and the properties of such solitons are shown to crucially depend on the trap topology. T