January 2006 arXiv papers — page 8

Atsuo Kuniba, Masato Okado, Reiho Sakamoto, Taichiro Takagi

The Kerov-Kirillov-Reshetikhin (KKR) bijection is the crux in proving fermionic formulas. It is defined by a combinatorial algorithm on rigged configurations and highest paths. We reformulate the KKR bijection as a vertex operator by purely using combinatorial R in crystal base theory. The result is viewed as a nested Bethe ansatz at q=0 as well as the direc

Thang T. Q. Le

We prove that the quantum SO(3)-invariant of an arbitrary 3-manifold $M$ is always an algebraic integer, if the order of the quantum parameter is co-prime with the order of the torsion part of $H_1(M,\BZ)$. An even stronger integrality, known as cyclotomic integrality, was established by Habiro for integral homology 3-spheres. Here we generalize Habiro's

Udo Baumgartner, Bertrand Remy, George A. Willis

The flat rank of a totally disconnected locally compact group G, denoted flat-rk(G), is an invariant of the topological group structure of G. It is defined thanks to a natural distance on the space of compact open subgroups of G. For a topological Kac-Moody group G with Weyl group W, we derive the inequalities: alg-rk(W)\le flat-rk(G)\le rk(|W|\_0). Here, al

Amit Acharya, Aarti Sawant

A non-perturbative approach to the time-averaging of nonlinear, autonomous ODE systems is developed based on invariant manifold methodology. The method is implemented computationally and applied to model problems arising in the mechanics of solids.

Marius van der Put, Marc Reversat

Choose $q\in {\mathbb C}$ with 0<|q|<1. The main theme of this paper is the study of linear q-difference equations over the field K of germs of meromorphic functions at 0. It turns out that a difference module M over K induces in a functorial way a vector bundle v(M) on the Tate curve $E_q:={\mathbb C}^*/q^{\mathbb Z}$. As a corollary one rediscovers Atiyah&

Anders Claesson, T. Kyle Petersen

The napkin problem was first posed by John H. Conway, and written up as a `toughie&#39; in &#34;Mathematical Puzzles: A Connoisseur&#39;s Collection,&#34; by Peter Winkler. To paraphrase Winkler&#39;s book, there is a banquet dinner to be served at a mathematics conference. At a particular table, $n$ men are to be seated around a circular table. There are $n

Jacques Boéchat, Maurice Mischler

Ce texte est une démontration complète de la conjecture de Catalan élabor\&#39; ee à la suite d&#39;un séminaire fait à Lausanne entre 2002 et 2004, juste après l&#39;annonce de la merveilleuse preuve de Preda Mihailescu

D. Kotschick, S. Morita

Making use of the extended flux homomorphism on the group of symplectomorphisms of a closed oriented surface of genus at least 2, we introduce new characteristic classes of foliated surface bundles with symplectic, equivalently area-preserving, total holonomy. These characteristic classes are stable with respect to the genus and we show that they are highly

Paolo Lisca

Let C be the contact structure naturally induced on the lens space L(p,q) by the standard contact structure on the three--sphere. We obtain a complete classification of the symplectic fillings of (L(p,q),C) up to orientation-preserving diffeomorphisms. In view of our results, we formulate a conjecture on the diffeomorphism types of the smoothings of complex

Oliver Schroeder

We study the quantum energy of the Z-string in 2+1 dimensions using the phase shift formalism. Our main interest is the question of stability of a Z-string carrying a finite fermion number.

H Weigel

In this talk I present recent studies on vacuum polarization energies and energy densities induced by QED flux tubes. I focus on comparing three and four dimensional scenarios and the discussion of various approximation schemes in view of the exact treatment.

Rene Meyer

Generalized Dilaton Theories in two dimensions coupled to Dirac fermions are subjected to constraint analysis. Three first class secondary constraints are found, corresponding to one local Lorentz symmetry and two diffeomorphisms. Moreover, the system also yields second class constraints from the fermions. The algebra of first class constraints is calculated

Leonardo Rastelli, Martijn Wijnholt

We show that Type IIB string theory on AdS_3 X S^3 X M_4 with p units of NS flux contains an integrable subsector, isomorphic to the minimal (p,1) bosonic string. To this end, we construct a topological string theory with target space Euclidean AdS_3 X S^3. We use a variant of Hamiltonian reduction to prove its equivalence to the minimal (p,1) string. The to

Marc Vanderhaeghen

It is reviewed how Compton scattering sum rules relate low-energy nucleon structure quantities to the nucleon excitation spectrum. In particular, the GDH sum rule and recently proposed extensions of it will be discussed. These extensions are sometimes more calculationally robust, which may be an advantage when estimating the chiral extrapolations of lattice

Luis Gonzalez-Mestres

Should projects of space experiments on ultra-high energy cosmic rays be supported, whatever AUGER results will turn out to be? We claim that this is indeed the case. It is now widely admitted that models of Lorentz symmetry violation (LSV) at the Planck scale based on power-like extrapolations down to cosmic-ray scales and able to account for a possible abs

W. Kilian, P. M. Zerwas

Experiments in the energy range from the scale of electroweak symmetry breaking to the TeV scale are expected to be crucial for unraveling the microscopic structure of matter and forces. The high precision which should be achieved in experiments at lepton colliders, is a necessary ingredient for providing a comprehensive picture of the mechanism breaking the

Amir H. Fariborz, Renata Jora, Joseph Schechter

Within a linear sigma model framework, possible mixing between two chiral nonets (a two quark nonet, and a four quark nonet) below 2 GeV is studied. Incorporating the U(1)$_A$ behavior of the underlying QCD, and working in the isospin invariant limit, the mass spectra of the I=0, $I=1/2$ and I=1 pseudoscalars, and the $I=1/2$ scalars are studied, and estimat

Tony Gherghetta

The theoretical tools required to construct models in warped extra dimensions are presented. This includes how to localise zero modes in the warped bulk and how to obtain the holographic interpretation using the AdS/CFT correspondence. Several models formulated in warped space are then discussed including nonsupersymmetric and supersymmetric theories as well

Jose N. Pecina-Cruz

This article proves that according to the principles of quantum mechanics the existence of elementary particles of negative mass is physically plausible. Heisenberg&#39;s uncertainty principle plays an important role in this demonstration. By reversing time, charge and mass are conjugated and the symmetry group is that of the Poincare with space-time reflect

S. Basak, R. G. Edwards, G. T. Fleming, U. M. Heller

The issues involved in a determination of the baryon resonance spectrum in lattice QCD are discussed. The variational method is introduced and the need to construct a sufficient basis of interpolating operators is emphasised. The construction of baryon operators using group-theory techniques is outlined. We find that the use both of quark-field smearing and

Jose Luis Hernandez Pastora

A new approximate solution of vacuum and stationary Einstein field equations is obtained. This solution is constructed by means of a power series expansion of the Ernst potential in terms of two independent and dimensionless parameters representing the quadrupole and the angular momentum respectively. The main feature of the solution is a suitable descriptio

Hakan Andreasson, Gerhard Rein

The stability features of steady states of the spherically symmetric Einstein-Vlasov system are investigated numerically. We find support for the conjecture by Zeldovich and Novikov that the binding energy maximum along a steady state sequence signals the onset of instability, a conjecture which we extend to and confirm for non-isotropic states. The sign of

Roman Plyatsko

The Fermi transport of the Dirac spinor is considered as a generalization of the parallel transport of this spinor which was introduced by V. Fock and D. Ivanenko (1929). The possible structure of the new variant of the general-relativistic Dirac equation based on the Fermi transport is discussed.

Vassilios S. Vassiliadis

A novel algorithm for tunable compression to within the precision of reproduction targets, or storage, is proposed. The new algorithm is termed the `Perceptron Algorithm&#39;, which utilises simple existing concepts in a novel way, has multiple immediate commercial application aspects as well as it opens up a multitude of fronts in computational science and

Mohammad-Reza Mozaffari, Keivan Esfarjani

The spin structure in a magnetic dot, which is an example of a quantum few-body system, is studied as a function of exchange coupling strength and dot size with in the semiclassical approximation on a discrete lattice. As the exchange coupli ng is decreased or the size is increased, the ground state undergoes a phase cha nge from a single domain ferromagnet

S. N. Klimin, J. T. Devreese

The results of recent measurements of the cyclotron resonance (CR) spectra for a GaAs quantum well are interpreted in terms of the resonant magnetopolaron effect. Owing to this effect, the CR peaks split near the TO-phonon frequency and also change their positions with respect to those obtained without electron-phonon interaction. The theoretical peak positi

V. K. Dugaev, J. Berakdar, J. Barnas

We show that in a magnetic nanowire with double magnetic domain walls, quantum interference results in spin-split quasistationary states localized mainly between the domain walls. Spin-flip-assisted transmission through the domain structure increases strongly when these size-quantized states are tuned on resonance with the Fermi energy, e.g. upon varying the

Peter Stefanovic, Mikko Haataja, Nikolas Provatas

We report on a novel extension of the recent phase-field crystal (PFC) method introduced in [Elder et al., Phys. Rev. Lett., Vol. 88, 245701:1-4 (2002)], which incorporates elastic interactions as well as crystal plasticity and diffusive dynamics. In our model, elastic interactions are mediated through wave modes that propagate on time scales many orders of

Patrick Ilg, J. -L. Barrat

The concept of effective temperatures in nonequilibrium systems is studied within an exactly solvable model of non-Markovian diffusion. The system is coupled to two heat baths which are kept at different temperatures: one (&#39;fast&#39;) bath associated with an uncorrelated Gaussian noise and a second (&#39;slow&#39;) bath with an exponential memory kernel.

J. Bettini, F. Sato, P. Z. Coura, S. O. Dantas

We present a study of the elongation and rupture of gold-silver alloy nanowires. Atomistic details of the evolution were derived from time-resolved atomic resolution transmission electron microscopy and molecular dynamics simulations. The results show the occurrence of gold enrichment at the nanojunction region, leading to a gold-like structural behavior eve

M. Reehuis, C. Ulrich, K. Prokes, A. Gozar

Neutron diffraction was used to determine the crystal structure and magnetic ordering pattern of a La2CuO4 single crystal, with and without applied magnetic field. A previously unreported, subtle monoclinic distortion of the crystal structure away from the orthorhombic space group Bmab was detected. The distortion is also present in lightly Sr-doped crystals

E. V. Correa Silva, Onofre Rojas, James E. F. Skea, S. M. de Souza

We present the $β$-expansion of the Helmholtz free energy of the classical $XYZ$ model, with a single-ion anisotropy term and in the presence of an external magnetic field, up to order $β^{12}$. We compare our results to the numerical solution of Joyce&#39;s [Phys. Rev. Lett. 19, 581 (1967)] expression for the thermodynamics of the $XXZ$ classical model, wit

R. Ilan, N. R. Cooper, Ady Stern

Following recent experiments, we consider current flow in two dimensional electronic systems in the quantum Hall regime where a gradient in the electron density induces a spatial variation in the Hall resistivity. Describing the system in terms of a spatially varying local resistivity tensor, we show that in such a system the current density is generically n

T. Arima, A. Tokunaga, T. Goto, H. Kimura

Lattice modulation and magnetic structures in magnetoelectric compounds Tb1-xDyxMnO3 have been studied around the ferroelectric (FE) Curie temperature T_C by x-ray and neutron diffraction. Temperature-independent modulation vectors through T_C are observed for the compounds with 0.50< x < 0.68. This indicates that ferroelectricity with a polarization (P) alo

R. J. O. Mossanek, M. Abbate

We studied the changes in the electronic structure of VO2 across the metal-insulator transition. The main technique was cluster model calculations with non-local screening channels. The calculation included a screening from a delocalized state at the Fermi level in the metallic phase, and a screening from the neighboring V site within the V-V dimmer in the i

M. Borromeo, F. Marchesoni

Transport in a one-dimensional symmetric device can be activated by the combination of thermal noise and a bi-harmonic drive. For the study case of an overdamped Brownian particle diffusing on a periodic one-dimensional substrate, we distinguish two apparently different bi-harmonic regimes: (i) Harmonic mixing, where the two drive frequencies are commensurat

A. Smogunov, A. Dal Corso, E. Tosatti

Electronic and transport properties of a short Ni nanowire suspended between two semi-infinite ferromagnetic Ni leads are explored in the framework of density-functional theory. The spin-dependent ballistic conductance of the nanowire is calculated using a scattering-based approach and the Landauer-Buttiker formula. The total calculated conductance in units

Alexander V. Tsukanov

We study theoretically the quantum dynamics of an electron in the symmetric four-level double-dot structure under the influence of the monochromatic resonant pulse. The probability amplitudes of the eigenstates relevant for the quantum dynamics are found from the solution of the non-stationary Schrödinger equation. The first-order correction term to the solu

W. V. Pogosov, K. Machida

We study the process of vortex nucleation in rotating two-dimensional BEC confined in a harmonic trap. We show that, within the Gross-Pitaevskii theory with the boundary condition of vanishing of the order parameter at infinity, topological defects nucleation occurs via the creation of vortex-antivortex pairs far from the cloud center, where the modulus of t

J. J. Xiao, K. W. Yu

The effective linear and third-order nonlinear optical properties of metallic colloidal crystal immersed in a graded-index host fluid are investigated theoretically. The local electric fields are extracted self-consistently based on the layer-to-layer interactions, which are readily given by the Lekner summation method. The resultant optical absorption and n

Minoru Soda, Yukio Yasui, Taketo Moyoshi, Masatoshi Sato

Neutron diffraction studies have been carried out in the temperature(T) range between 10 K and 130 K on a single crystal of YBaCo4O7, which has the stacking of kagome and triangular lattices of CoO4 tetrahedra along the c-axis. Structural transitions have been found at two temperatures Tc1~70 K and Tc2~105 K. With decreasing T, magnetic order appears along w

S. Y. Liu, X. L. Lei, Norman J. M. Horing

We present a quantum Boltzmann equation analysis of the spin-Hall effect in a diffusive Rashba two-dimensional electron system. Within the framework of the self-consistent Born approximation, we consider the roles of disorder-induced quasiclassical relaxation, collisional broadening of the quasiparticles, and the intracollisional field effect in regard to sp

R. S. Markiewicz, A. Bansil

We present a three-band Hubbard Hamiltonian and the associated Cu K-edge RIXS spectra for electron and hole doped cuprates over a wide range of energy and momentum transfers. By comparing computed spectra for the unfilled case with the corresponding results for 15% electron or hole doping at two different values of the effective Hubbard parameter U, generic

R. van Zon, E. G. D. Cohen

The distribution of the initial short-time displacements of particles is considered for a class of classical systems under rather general conditions on the dynamics and with Gaussian initial velocity distributions, while the positions could have an arbitrary distribution. This class of systems contains canonical equilibrium of a Hamiltonian system as a speci

Deok-Sun Lee, Heiko Rieger

The problem of sending the maximum amount of flow $q$ between two arbitrary nodes $s$ and $t$ of complex networks along links with unit capacity is studied, which is equivalent to determining the number of link-disjoint paths between $s$ and $t$. The average of $q$ over all node pairs with smaller degree $k_{\rm min}$ is $<q>_{k_{\rm min}} \simeq c k_{\rm mi

M. P. Muno, F. E. Bauer, R. M. Bandyopadhyay, Q. D. Wang

We present the catalog of X-ray sources detected in a shallow Chandra survey of the inner 2 by 0.8 degrees of the Galaxy, and in two deeper observations of the Radio Arches and Sgr B2. The catalog contains 1352 objects that are highly-absorbed (N_H > 4e22 cm^-2 and are therefore likely to lie near the Galactic center (D~8 kpc), and 549 less-absorbed sources

Todd A. Thompson, Eliot Quataert, Eli Waxman, Norman Murray

We estimate minimum energy magnetic fields (B_min) for a sample of galaxies with measured gas surface densities, spanning from normal spirals to starbursts. We show that the ratio of the minimum energy magnetic pressure to the total pressure in the ISM decreases substantially with increasing surface density; for Arp 220 this ratio is ~10^-4. Therefore, if th

G. A. Wade, A. W. Fullerton, J. -F. Donati, J. D. Landstreet

In this paper we confirm the presence of a globally-ordered, kG-strength magnetic field in the photosphere of the young O star $θ^1$~Orionis~C, and examine the properties of its optical line profile variations. A new series of high-resolution MuSiCoS Stokes $V$ and $I$ spectra has been acquired which samples approximately uniformly the rotational cycle of $θ

G. A. Wade, M. Auriere, S. Bagnulo, J. -F. Donati

With this work, we have conducted an extensive search for magnetic fields in the photosphere of $α$~And. We have acquired new circular polarisation spectra with the MuSiCoS and ESPaDOnS sp ectropolarimeters. We have also obtained FORS1 circular polarisation spectra fro m the ESO Archive, and considered all previously published magnetic data. This e xtensive

Kwang-Il Seon, Wonyong Han, Uk-Won Nam, Jang-Hyun Park

We present far-ultraviolet (FUV) spectral images, measured at C IV 1550, He II 1640, Si IV+O IV] 1400, and O III] 1664, of the entire Cygnus Loop, observed with the Spectroscopy of Plasma Evolution from Astrophysical Radiation (SPEAR) instrument, also known as FIMS. The spatial distribution of FUV emission generally corresponds with a limb-brightened shell,

G. H. Marion, P. Hoeflich, J. C. Wheeler, E. L. Robinson

We investigate the quantity and composition of unburned material in the outer layers of three normal Type Ia supernovae (SNe Ia): 2000dn, 2002cr and 20 04bw. Pristine matter from a white dwarf progenitor is expected to be a mixture of oxygen and carbon in approximately equal abundance. Using near-infrared (NIR, 0.7-2.5 microns) spectra, we find that oxygen i

Ph. Jetzer, M. Sereno

We discuss the influence of the cosmological constant on the gravitational equations of motion of bodies with arbitrary masses and eventually solve the two-body problem. Observational constraints are derived from measurements of the periastron advance in stellar systems, in particular binary pulsars and the solar system. Up to now, Earth and Mars data give t

Valentine Wakelam, Eric Herbst, Franck Selsis

The gas-phase chemistry of dark clouds has been studied with a treatment of uncertainties caused both by errors in individual rate coefficients and uncertainties in physical conditions. Moreover, a sensitivity analysis has been employed to attempt to determine which reactions are most important in the chemistry of individual species. The degree of overlap be

P. E. Verrier, N. W. Evans

The binary star system gamma Cephei is unusual in that it harbours a stable giant planet around the larger star at a distance only about a tenth of that of the stellar separation. Numerical simulations are carried out into the stability of test particles in the system. This provides possible locations for additional planets and asteroids. To this end, the re

E. Falgarone, G. Pineau Des Forêts, P. Hily-Blant, P. Schilke

Results: We report the detection of broad HCO+(1-0) lines (10 mK < T < 0.5 K). The interpretation of 10 of the HCO+ velocity components is conducted in conjunction with that of the associated optically thin 13CO emission. The derived HCO+ column densities span a broad range, $10^{11}< N(HCO+)/Δv <4 \times 10^{12} \rm cm^2/(km/s^{-1}$, and the inferred HCO+ a

Henny J. G. L. M. Lamers, Peter Anders, Richard de Grijs

We calculated the broad-band photometric evolution of unresolved star clusters, including the preferential loss of low-mass stars due to mass segregation. The stellar mass function of a cluster evolves due to three effects: (a) the evolution of massive stars; (b) early tidal effects reduce the mass function independently of the stellar mass; (c) after mass s

Pierre Hily-Blant, David Teyssier, Sabin Philipp, Rolf Gusten

Using large scale maps in C18O(2-1) and in the continuum at 1.2mm obtained at the IRAM-30m antenna with the Heterodyne Receiver Array (HERA) and MAMBO2, we investigated the morphology and the velocity field probed in the inner layers of the Horsehead nebula. The data reveal a non--self-gravitating (m/mvir = 0.3) filament of dust and gas (the &#34;neck&#34;,

R. J. Cohen, N. Gasipron, J. Meaburn, M. F. Graham

MERLIN measurements of 1.6-GHz OH masers associated with Orion-BN/KL are presented, and the data are compared with data on other masers, molecular lines, compact radio continuum sources and infrared sources in the region. OH masers are detected over an area 30 arcsec in diameter, with the majority lying along an approximately E-W structure that extends for a

Pierre Salati

The astronomical dark matter could be made of weakly interacting massive species whose mutual annihilations should produce antimatter particles and distortions in the corresponding energy spectra. The propagation of cosmic rays inside the Milky Way plays a crucial role and is briefly presented. The uncertainties in its description lead to considerable variat

Norma G. Sanchez

We compute the quantum string entropy S_s(m,j) of the microscopic string states of mass m and spin j in two physically relevant backgrounds: Kerr (rotating) black holes and de Sitter (dS) space-time. We find a new formula for the quantum gravitational entropy S_{sem} (M, J), as a function of the usual Bekenstein-Hawking entropy S_{sem}^(0)(M, J). We compute

H. J. de Vega, N. G. Sanchez

We show that the self-gravitating gas at thermal equilibrium has an infinite volume limit in the three ensembles (GCE, CE, MCE) when (N, V) -> infty, keeping N/V^{1/3} fixed, that is, with eta = G m^2 N/[ V^{1/3} T] fixed. We develop MonteCarlo simulations, analytic mean field methods (MF) and low density expansions. We compute the equation of state and find

Daniel B. Zucker, Alexei Y. Kniazev, David Martinez-Delgado, Eric F. Bell

We report the discovery of Andromeda X, a new dwarf spheroidal satellite of M31, based on stellar photometry from the Sloan Digital Sky Survey (SDSS). Using follow-up imaging data we have estimated its distance and other physical properties. We find that Andromeda X has a dereddened central surface brightness of mu_V,0 ~ 26.7 mag arcsec^-2 and a total appare

Marian Douspis, Nabila Aghanim, Mathieu Langer

We reanalyse Cosmic Microwave Background data from experiments probing both large and small scales. We assume that measured anisotropies are due not only to primary fluctuations but also, especially at small scales, to secondary effects (namely the Sunyaev-Zel&#39;dovich effect) and possible point source contaminations. We first consider primary and secondar

J. Garcia-Rojas, C. Esteban, M. Peimbert, M. T. Costado

We present deep echelle spectrophotometry of the Galactic {\hii} regions M16, M20 and NGC 3603. The data have been taken with the Very Large Telescope Ultraviolet-Visual Echelle Spectrograph in the 3100 to 10400 Årange. We have detected more than 200 emission lines in each region. Physical conditions have been derived using different continuum and line inten

Armando Bernui, Thyrso Villela, Carlos A. Wuensche, Rodrigo Leonardi

We study the large-scale angular correlation signatures of the Cosmic Microwave Background (CMB) temperature fluctuations from WMAP data in several spherical cap regions of the celestial sphere, outside the Kp0 or Kp2 cut-sky masks. We applied a recently proposed method to CMB temperature maps, which permits an accurate analysis of their angular correlations

Paul C. Hewett, Stephen J. Warren, Sandy K. Leggett, Simon T. Hodgkin

The UKIRT Infrared Deep Sky Survey is a set of five surveys of complementary combinations of area, depth, and Galactic latitude, which began in 2005 May. The surveys use the UKIRT Wide Field Camera (WFCAM), which has a solid angle of 0.21deg^2. Here we introduce and characterise the ZYJHK photometric system of the camera, which covers the wavelength range 0.

F. P. Keenan, J. J. Drake, S. Chung, N. S. Brickhouse

Recent calculations of atomic data for Fe XV have been used to generate theoretical line ratios involving n = 3-4 transitions in the soft X-ray spectral region (52-83 A), for a wide range of electron temperatures and densities applicable to solar and stellar coronal plasmas. A comparison of these with solar flare observations from a rocket-borne spectrograph

K. Ryu, K. W. Min, J. W. Park, D. H. Lee

The first FUV (lambda lambda 1350-1750 A) spectral imaging observations of the Eridanus superbubble, obtained with the SPEAR/FIMS mission, have revealed distinct fluorescent emission from molecular hydrogen. In this study, the observed emission features were compared with those from a photo-dissociation region model with assumed illuminating stellar fields.

A. V. Moiseev

We have considered some results concerning gas and stars kinematics of nearby galaxies recently obtained on the SAO RAS 6m telescope using the panoramic spectroscopy methods. The circumnuclear regions of the galaxies were observed with integral-field spectrograph MPFS. The large-scale ionized gas kinematics was studied with the scanning Fabry-Perot interfero

Jerry Edelstein, Eric Korpela, Joe Adolfo, Mark Bowen

The SPEAR (or &#39;FIMS&#39;) instrumentation has been used to conduct the first large-scale spectral mapping of diffuse cosmic far ultraviolet (FUV, 900-1750 AA) emission, including important diagnostics of interstellar hot (10^4 K - 10^6 K) and photoionized plasmas, H_2, and dust scattered starlight. The instrumentation&#39;s performance has allowed for th

J. Edelstein, K. W. Min, W. Han, E. J. Korpela

The Spectroscopy of Plasma Evolution from Astrophysical Radiation (or the Far-ultraviolet Imaging Spectrograph) instruments, flown aboard the STSAT-1 satellite mission, have provided the first large-area spectral mapping of the cosmic far ultraviolet (FUV, lambda 900-1750 Ang) background. We observe diffuse radiation from hot (10^4 to 10^6 K) and ionized pla

K. Nishikida, J. Edelstein, E. J. Korpela, R. Sankrit

We present far-ultraviolet (FUV) spectral-imaging observations of the Vela supernova remnant (SNR), obtained with the Spectroscopy of Plasma Evolution from Astrophysical Radiation (SPEAR) instrument, also known as FIMS. The Vela SNR extends 8 degrees in the FUV and its global spectra are dominated by shock-induced emission lines. We find that the global FUV

Wolfgang Steffen, Jose Alberto Lopez

We present a powerful new tool to analyse and disentangle the 3-D geometry and kinematic structure of gaseous nebulae. The method consists in combining commercially available digital animation software to simulate the 3-D structure and expansion pattern of the nebula with a dedicated, purpose built rendering software that produces the final images and long s

J. Kregenow, J. Edelstein, E. Korpela, B. Welsh

Diffuse far-UV emission arising from the edge of the Orion-Eridanus superbubble was observed with the SPEAR imaging spectrometer, revealing numerous emission lines arising from both atomic species and H2. Spatial variations in line intensities of CIV, SiII, and OVI, in comparison with soft X-ray, H-alpha and dust data, indicate that these ions are associated

Eric J. Korpela, Jerry Edelstein, Julia Kregenow, Kaori Nishikida

We present SPEAR/FIMS far-ultraviolet observations near the North Ecliptic Pole. This area, at b~30 degrees and with intermediate HI column, seems to be a fairly typical line of sight that is representative of general processes in the diffuse ISM. We detect a surprising number of emission lines of many elements at various ionization states representing gas p

H. J. de Vega, N. Sanchez

We provide a complete picture to the self-gravitating non-relativistic gas at thermal equilibrium using Monte Carlo simulations, analytic mean field methods (MF) and low density expansions. The system is shown to possess an infinite volume limit in the grand canonical (GCE), canonical (CE) and microcanonical (MCE) ensembles when (N, V) -> infty, keeping N/V^

Biping Gong, G. F. Bignami

The strange timing property of X-ray pulsar 1E 1207.4-5209 can be explained by the hypothesis that it is a member of an ultra-compact binary system. This paper confronts the ultra-compact assumption with the observed properties of this pulsar. The gravitational potential well of an ultra-compact binary can enlarge the corotation radius and thus make it possi

G. T. Laurent, J. Glenn, E. Egami, G. H. Rieke

We present 350 micron photometry of all 17 galaxy candidates in the Lockman Hole detected in a 1.1 mm Bolocam survey. Several of the galaxies were previously detected at 850 microns, at 1.2 mm, in the infrared by Spitzer, and in the radio. Nine of the Bolocam galaxy candidates were detected at 350 microns and two new candidates were serendipitously detected

Shabnam Shafiee, Sennur Ulukus

We investigate the behavior of two users and one jammer in an AWGN channel with and without fading when they participate in a non-cooperative zero-sum game, with the channel&#39;s input/output mutual information as the objective function. We assume that the jammer can eavesdrop the channel and can use the information obtained to perform correlated jamming. U

I. V. Bondarev, B. Vlahovic

We analyze optical absorption by atomically doped carbon nanotubes with a special focus on the frequency range close to the atomic transition frequency. We derive the optical absorbtion line-shape function and, having analyzed particular achiral nanotubes of different diameters, predict the effect of absorbtion line splitting due to strong atom-vacuum-field

Louis Gaudreau, Sergei Studenikin, Andy Sachrajda, Piotr Zawadzki

Quantum dots are considered building blocks for future quantum information circuits. We present here experimental results on a quantum dot circuit consisting of three quantum dots with controlled electron numbers down to one per dot and tunable coupling. We experimentally map out for the first time the stability diagram of the triatomic system and reveal the

Aneesh V. Manohar, Mark B. Wise

We explore the impact of new SU(3)XSU(2)XU(1) invariant interactions characterized by a scale of order a TeV on Higgs boson properties. The Higgs production rate and branching ratios can be very different from their standard model values. We also discuss the possibility that these new interactions contribute to acceptable unification of the gauge couplings.

Paulo F. Bedaque, Ikuro Sato, Andre Walker-Loud

Lattice QCD studies of hadron-hadron interactions are performed by computing the energy levels of the system in a finite box. The shifts in energy levels proportional to inverse powers of the volume are related to scattering parameters in a model independent way. In addition, there are non-universal exponentially suppressed corrections that distort this rela

M. M. Block

We here comment on a series of recent papers by Igi and Ishida[K. Igi and M. Ishida, Phys. Lett B 622, 286 (2005)] and Block and Halzen[M. M. Block and F. Halzen, Phys. Rev D 72, 036006 (2005)] that fit high energy $pp$ and $\bar pp$ cross section and $ρ$-value data, where $ρ$ is the ratio of the real to the imaginary portion of the forward scattering amplit

F. Gelis, R. Venugopalan

We develop a formalism for particle production in a field theory coupled to a strong time-dependent external source. An example of such a theory is the Color Glass Condensate. We derive a formula, in terms of cut vacuum-vacuum Feynman graphs, for the probability of producing a given number of particles. This formula is valid to all orders in the coupling con

Suk Bum Chung, Michael Stone

To detect non-abelian statistics in the $ν= 12/5$ quantum Hall state through interferometry, we apply an analysis similar to the ones proposed for the non-abelian $ν= 5/2$ quantum Hall state. The result is that the amplitude of the Aharonov-Bohm oscillation of this interference is dependent on the internal states of quasiholes, but, in contrast to the $ν= 5/

Neil Yorke-Smith, Carmen Gervet

Constraint Programming (CP) has proved an effective paradigm to model and solve difficult combinatorial satisfaction and optimisation problems from disparate domains. Many such problems arising from the commercial world are permeated by data uncertainty. Existing CP approaches that accommodate uncertainty are less suited to uncertainty arising due to incompl

Wojciech Dorabiala, Mark W. Johnson

We verify the Becker-Shultz axioms characterizing the Becker-Gottlieb transfer $τ$ for the composite of the algebraic K-theory transfer of any perfect fibration followed by the trace map. As a consequence, for any compact ANR fibration (those considered by Becker-Shultz), $τ$ is homotopy equivalent to the composite of the algebraic K-theory transfer followed

Aninda Sinha, Nemani V. Suryanarayana

We study stretched horizons of the type AdS_2 x S^8 for certain spherically symmetric extremal small black holes in type IIA carrying only D0-brane charge making use of Sen&#39;s entropy function formalism for higher derivative gravity. A scaling argument is given to show that the entropy of this class of black holes for large charge behaves as \sqrt{|q|} wh

F. Shankar, A. Lapi, P. Salucci, G. De Zotti

We present new relationships between halo masses M_h and several galaxy properties, including r*-band luminosities L_r, stellar (M_star) and baryonic masses, stellar velocity dispersions (sigma), and black hole masses (M_BH). Approximate analytic expressions are given. In the galaxy halo mass range 3*10^(10) M_sun <= M_h <= 3*10^(13) M_sun the M_h-L_r, M_sta

Ivan Saika-Voivod, Peter H. Poole, Richard K. Bowles

We test classical nucleation theory (CNT) in the case of simulations of deeply supercooled, high density liquid silica, as modelled by the BKS potential. We find that at density $ρ=4.38$~g/cm$^3$, spontaneous nucleation of crystalline stishovite occurs in conventional molecular dynamics simulations at temperature T=3000 K, and we evaluate the nucleation rate

Vladimir Lobaskin, Burkhard Duenweg, Martin Medebach, Thomas Palberg

We study the electrophoretic mobility of spherical charged colloids in a low-salt suspension as a function of the colloidal concentration. Using an effective particle charge and a reduced screening parameter, we map the data for systems with different particle charges and sizes, including numerical simulation data with full electrostatics and hydrodynamics a

F. Maltoni, J. Spengler, M. Bargiotti, A. Bertin

We present an analysis of the existing data on charmonium hadro-production based on non-relativistic QCD (NRQCD) calculations at the next-to-leading order (NLO). All the data on J/psi and psi&#39; production in fixed-target experiments and on pp collisions at low energy are included. We find that the amount of color octet contribution needed to describe the

James G. Bartlett

Cosmic microwave background (CMB) anisotropy is our richest source of cosmological information; the standard cosmological model was largely established thanks to study of the temperature anisotropies. By the end of the decade, the Planck satellite will close this important chapter and move us deeper into the new frontier of polarization measurements. Numerou

Peter Ozsvath, Zoltan Szabo

We show that link Floer homology detects the Thurston norm of a link complement. As an application, we show that the Thurston polytope of an alternating link is dual to the Newton polytope of its multi-variable Alexander polynomial. To illustrate these techniques, we also compute the Thurston polytopes of several specific link complements.

Nick Dorey, Benoit Vicedo

We study the dynamics of finite-gap solutions in classical string theory on R x S^3. Each solution is characterised by a spectral curve, Σ, of genus g and a divisor, γ, of degree g on the curve. We present a complete reconstruction of the general solution and identify the corresponding moduli-space, M^(2g)_R, as a real symplectic manifold of dimension 2g. Th

Andrea Altomani

We prove a relation between the $\bar\partial_M$ cohomology of a minimal orbit $M$ of a real form $G_0$ of a complex semisimple Lie group $G$ in a flag manifold $G/Q$ and the Dolbeault cohomology of the Matsuki dual open orbit $X$ of the complexification $K$ of a maximal compact subgroup $K_0$ of $G_0$, under the assumption that $M$ is Levi-flat.

George B. Field, Eric G. Blackman, Eric Keto

We present a model in which the supersonic motions observed in molecular clouds are driven by gravitational energy released as large structures fragment into smaller ones. The fragmentation process begins in large molecular clouds, and continues down to fragments of a critical mass, at which gravitational confinement may be replaced by pressure confinement.

Paolo Desiati

AMANDA-II is the largest neutrino telescope collecting data at the moment, and its main goal is to search for sources of high energy extra-terrestrial neutrinos. The detection of such sources could give non-controversial evidence for the acceleration of charged hadrons in cosmic objects like Supernova Remnants, Micro-quasars, Active Galactic Nuclei or Gamma

Stefano Giusto, Samir D. Mathur, Yogesh K. Srivastava

We start with a 2-charge D1-D5 BPS geometry that has the shape of a ring; this geometry is regular everywhere. In the dual CFT there exists a perturbation that creates one unit of excitation for left movers, and thus adds one unit of momentum P. This implies that there exists a corresponding normalizable perturbation on the near-ring D1-D5 geometry. We find