December 2006 arXiv papers — page 29

L. B. Holanda, R. S. Marques de Carvalho, A. Mihara

The study of charmonium dissociation in heavy ion collisions is generally performed in the framework of effective Lagrangians with meson exchange. Some studies are also developed with the intention of calculate form factors and coupling constants related with charmed and light mesons. These quantities are important in the evaluation of charmonium cross secti

Mathias Garny

We discuss a toy model where baryogenesis and cosmic acceleration are driven by a leptonic quintessence field coupled to the standard model sector via a massive mediating scalar field. It does not require the introduction of B-L-violating interactions below the inflationary scale. Instead, a B-L-asymmetry is stored in the quintessence field, which compensate

Amal Kr. Sarma, H. Zeen Devi, N. Nimai Singh

We compute and also compare the contributions of canonical and noncanonical mass terms towards baryon asymmetry by considering type-II seesaw mass models of neutrinos: Degenerare(3 varieties), Normal hierarchical and Inverted hierarchical(2 varieties). We have shown that for particular choices of parameter '$γ$'(the so-called discriminator) for diffe

Jihn E. Kim

The current status of axion physics is presented. There still exists the axion window 10^9 GeV < F_a < 10^{12} GeV. The recent CAST solar axion search experiment on the axion-photon-photon coupling strength has to be improved by a factor of 100 to reach down to the region of superstring axions. The calculable theta and m_u=0 cases for strong CP solutions, an

Daniel S. Carman

One of the unanswered and most fundamental questions in physics regards the nature of the confinement mechanism of quarks and gluons in QCD. Exotic hybrid mesons manifest gluonic degrees of freedom and their spectroscopy will provide the data necessary to test assumptions in lattice QCD and the specific phenomenology leading to confinement. Within the past t

T. Aaltonen

We present a measurement of the top-quark mass, $M_{\mathrm{top}}$, in the all-hadronic decay channel $t\bar{t} \to W^+b W^- \bar{b} \to q_1\bar{q}_2 b q_3 \bar{q}_4 \bar{b}$. The analysis is performed using 310 pb$^{-1}$ of $\sqrt{s}$=1.96 TeV $p\bar{p}$ collisions collected with the CDF II detector using a multi-jet trigger. The mass measurement is based o

B Collaboration, I. Abt

The b-bbar production cross section in 920 GeV proton-nucleus fixed target collisions is measured by observing double muonic decays of b-flavored hadrons in the kinematic region $-0.3<\xF(μ)<0.15$. A total number of $76\pm12$ b-bbar events is obtained with a likelihood fit of the signal and background simulated events to the data. The resulting cross section

Valerio Faraoni, Shahn Nadeau

The issue of the equivalence between Jordan and Einstein conformal frames in scalar-tensor gravity is revisited, with emphasis on implementing running units in the latter. The lack of affine parametrization for timelike worldlines and the cosmological constant problem in the Einstein frame are clarified, and a paradox in the literature about cosmological sin

D. Rideout, S. Zohren

The finiteness of black hole entropy suggest that spacetime is fundamentally discrete, and hints at an underlying relationship between geometry and &#34;information&#34;. The foundation of this relationship is yet to be uncovered, but should manifest itself in a theory of quantum gravity. We review recent attempts to define a microscopic measure for black ho

V. I. Man&#39;ko, G. Marmoand C. Stornaiolo

The probability representation of quantum mechanics including propagators and tomograms of quantum states of the universe and its application to quantum gravity and cosmology are reviewed. The minisuperspaces modeled by oscillator, free pointlike particle and repulsive oscillator are considered. The notion of tomographic entropy and its properties are used t

Sergei Alexandrov, Eric Buffenoir, Philippe Roche

We establish an equivalence between the Hamiltonian formulation of the Plebanski action for general relativity and the covariant canonical formulation of the Hilbert-Palatini action. This is done by comparing the symplectic structures of the two theories through the computation of Dirac brackets. We also construct a shifted connection with simplified Dirac b

Jiro Soda, Sugumi Kanno

We discuss the impact of Lorentz violation on the cosmology. Firstly, we show that the Lorentz violation affects the dynamics of the chaotic inflationary model and gives rise to an interesting feature. Secondly, we propose the Lorentz violating DGP brane models where the Lorentz violating terms on the brane accelerate the current universe. We conjecture that

Ignatios Antoniadis, Pawel O. Mazur, Emil Mottola

We present an approach to the problem of vacuum energy in cosmology, based on dynamical screening of Lambda on the horizon scale. We review first the physical basis of vacuum energy as a phenomenon connected with macroscopic boundary conditions, and the origin of the idea of its screening by particle creation and vacuum polarization effects. We discuss next

Esben Rune Hansen, Henrik Reif Andersen

A product configurator which is complete, backtrack free and able to compute the valid domains at any state of the configuration can be constructed by building a Binary Decision Diagram (BDD). Despite the fact that the size of the BDD is exponential in the number of variables in the worst case, BDDs have proved to work very well in practice. Current BDD-base

Jianwen Zhang, Marc A. Armand

A transform that enables generator-matrix-based Reed-Solomon (RS) coded data to be recovered under interpolation-based list decoding is presented. The transform matrix needs to be computed only once and the transformation of an element from the output list to the desired RS coded data block incurs $k^{2}$ field multiplications, given a code of dimension $k$.

Karim El Defrawy, Athina Markopoulou, Katerina Argyraki

Distributed Denial-of-Service (DDoS) attacks are a major problem in the Internet today. In one form of a DDoS attack, a large number of compromised hosts send unwanted traffic to the victim, thus exhausting the resources of the victim and preventing it from serving its legitimate clients. One of the main mechanisms that have been proposed to deal with DDoS i

Lunjin Lu

This paper presents a new type analysis for logic programs. The analysis is performed with a priori type definitions; and type expressions are formed from a fixed alphabet of type constructors. Non-discriminative union is used to join type information from different sources without loss of precision. An operation that is performed repeatedly during an analys

Xianwei Sha, R. E. Cohen

We investigate the elastic and isotropic aggregate properties of ferromagnetic bcc iron as a function of temperature and pressure by computing the Helmholtz free energies for the volume-conserving strained structures using the first-principles linear response linear-muffin-tin-orbital method and the generalized-gradient approximation. We include the electron

Brett I. Dunlap, Shashi P. Karna, Rajendra R. Zope, ;

Molecular dipole moments of analytic density-functional theory are investigated. The effect of element-dependent exchange potentials on these moments are examined by comparison with conventional quantum-chemical methods and experiment for the subset of the extended G2 set of molecules that have nonzero dipole moment. Fitting the Kohn-Sham [Phys. Rev. 140, A1

Peter L. Hagelstein, Irfan U. Chaudhary

We consider models in which two sets of matched two-level systems are coupled to a common oscillator in the case where the oscillator energy is small relative to the two-level transition energies. Since the two sets of two-level systems are coupled indirectly through the oscillator, excitation transfer from one set of two-level systems to the other is possib

Christopher Jarzynski

Recent theoretical predictions and experimental measurements have demonstrated that equilibrium free energy differences can be obtained from exponential averages of nonequilibrium work values. These results are similar in structure, but not equivalent, to predictions derived nearly three decades ago by Bochkov and Kuzovlev, which are also formulated in terms

B. Detlefs, S. B. Wilkins, P. Javorský, E. Blackburn

Experiments with resonant photons at the U M4 edge have been performed on a sample of USb_{0.9}Te_{0.1}, which has an incommensurate magnetic structure with k = 0.596(2) reciprocal lattice units. The reflections of the form <kkk>, as observed previously in a commensurate k = 1/2 system [N. Bernhoeft et al., Phys. Rev. B 69 174415 (2004)] are observed, removi

Paolo Allegrini, Mauro Bologna, Paolo Grigolini, Bruce J. West

The dynamical emergence (and subsequent intermittent breakdown) of collective behavior in complex systems is described as a non-Poisson renewal process, characterized by a waiting-time distribution density $ψ(τ)$ for the time intervals between successively recorded breakdowns. In the intermittent case $ψ(t)\sim t^{-μ}$, with complexity index $μ$. We show tha

Alessandro Campa, Ramaz Khomeriki, David Mukamel, Stefano Ruffo

We study theoretically layered spin systems where long-range dipolar interactions play a relevant role. By choosing a specific sample shape, we are able to reduce the complex Hamiltonian of the system to that of a much simpler coupled rotator model with short-range and mean-field interactions. This latter model has been studied in the past because of its int

R. H. Miwa, T. M. Schmidt, A. Fazzio

We have performed an {\it ab initio} total energy investigation, within the density functional theory (DFT), of antisite defects in InP nanowires (InP$NW$s) grown along the [111] direction. Our total energy results indicate that, (i) P antisites (P$_{\rm In}$) are the most likely antisite defect compared with In antisites (In$_{\rm P}$), and (ii) the formati

C. Hess, H. ElHaes, A. Waske, B. Büchner

We present experimental results for the thermal conductivity $κ$ of the pseudo 2-leg ladder material $\rm CaCu_2O_3$. The strong buckling of the ladder rungs renders this material a good approximation to a $S=1/2$ Heisenberg-chain. Despite a strong suppression of the thermal conductivity of this material in all crystal directions due to inherent disorder, we

S. I. Mukhin

A mechanism of self-organized one-dimensionality in correlated electron system coupled to optical phonon mode is proposed. It is found that a lattice vibration may compactify electron motion effectively to a one-dimensional space and trigger quantum phase transition into ordered state with &#34;extended van Hove singularities&#34; in the electronic Floquet m

Jiaguang Han, Fan Wan, Zhiyuan Zhu, Weili Zhang

We report far-infrared dielectric properties of powder form ferroelectric SrTiO3. Terahertz time-domain spectroscopy (THz-TDS) measurement reveals that the low-frequency dielectric response of SrTiO3 is a consequence of the lowest transverse optical (TO) soft mode TO1 at 2.70 THz (90.0 1/cm), which is directly verified by Raman spectroscopy. This result prov

Martin Rost, Lasse Laurson, Martin Dube, Mikko Alava

Interfaces moving in a disordered medium exhibit stochastic velocity fluctuations obeying universal scaling relations related to the presence or absence of conservation laws. For fluid invasion of porous media, we show that the fluctuations of the velocity are governed by a geometry-dependent length scale arising from fluid conservation. This result is compa

Christian Flindt, Anders S. Sorensen, Karsten Flensberg

We elaborate on a number of issues concerning our recent proposal for spin-qubit manipulation in nanowires using the spin-orbit coupling. We discuss the experimental status and describe in further detail the scheme for single-qubit rotations. We present a derivation of the effective two-qubit coupling which can be extended to higher orders in the Coulomb int

Sergey L. Bud&#39;ko, Paul C. Canfield, Marcos A. Avila, Toshiro Takabatake

We present detailed, low temperature, magnetoresistance and specific heat data of single crystal YbNiSi3 measured in magnetic field applied along the easy magnetic axis, H || b. An initially antiferromagnetic ground state changes into a field-induced metamagnetic phase at ~16 kOe (T -> 0). On further increase of magnetic field, magnetic order is suppressed a

O. Caha, V. Holý, Kevin E. Bassler

Continuum simulations of self-organized lateral compositional modulation growth in InAs/AlAs short-period superlattices on InP substrate are presented. Results of the simulations correspond quantitatively to the results of synchrotron x-ray diffraction experiments. The time evolution of the compositional modulation during epitaxial growth can be explained on

T. Yang, M. Hara, A. Hirohata, T. Kimura

We fabricated Co nano-rings incorporated in the vertical pseudo-spin-valve nanopillar structures with deep submicron lateral sizes. It is shown that the current-perpendicular-to-plane giant magnetoresistance can be used to characterize a very small magnetic nano-ring effectively. Both the onion state and the flux-closure vortex state are observed. The Co nan

Sailaja Krishnamurty, Ghazal Shafai, D. G. Kanhere, B. Soulé de Bas

Density functional molecular dynamics simulations have been carried out to understand the finite temperature behavior of Au$_{19}$ and Au$_{20}$ clusters. Au$_{20}$ has been reported to be a unique molecule having tetrahedral geometry, a large HOMO-LUMO energy gap and an atomic packing similar to that of the bulk gold (J. Li et al., Science, {\bf 299} 864, 2

A. S. Cherny, K. G. Dergachev, M. I. Kobets, E. N. Khatsko

The static magnetic and dynamic properties of the compound (NH3)2(CH2)3CoCl4 are investigated in the temperature interval 0.5-50 K. It is shown that at TN =2.05 K this compound undergoes a transition to a magnetically ordered antiferromagnet state. A distinctive feature of this compound is the presence of temperature hysteresis at the transition to the order

Adam Wasserman, Nimrod Moiseyev

We show that under well-defined conditions the Hohenberg-Kohn theorem (HKT) can be extended to the lowest-energy resonance of unbound systems. Using the Gel&#39;fand Levitan theorem, the extended version of the HKT can also be applied to systems that support a finite number of bound states. The extended version of the HKT provides an adequate framework to ca

Francesco Operetto, Francesco Pederiva

We employed a fully optimized Shadow Wave Function (SWF) in combination with Variational Monte Carlo techniques to investigate the properties of HD molecules and molecular ortho-deuterium (o-D_2) in bulk solid para-hydrogen (p-H_2). Calculations were performed for different concentrations of impurities ranging from about 1% to 25% at the equilibrium density

Francesco Operetto, Francesco Pederiva

We present results of Diffusion Monte Carlo calculations for a system of solid ortho-D_2 at different densities, for pressure ranging from 0 up to 350MPa. We compare the equation of state obtained using two of the most used effective intermolecular potentials, i.e. the Silvera--Goldman and the Buck potentials, with experimental data, in order to assess the v

Simanta C., Yatendra S. Jain

The singularity of specific heat ($C_p$) and related properties (viz. thermal expansion coefficient, compressibility and pressure coefficient) of liquid $^4He$ at $λ-$point is studied and the accuracy of its logarithmic nature as concluded for the first time from a microscopic theory (cond-mat/0606571) of a system of interacting bosons is examined. A very go

Jose Antonio Carrillo, Thorsten Poeschel, Clara Saluena

A numerical hydrodynamic model of a vibrated granular bed in 2D is elaborated based on a highly accurate Shock Capturing scheme applied to the compressible Navier-Stokes equations for granular flow. The hydrodynamic simulation of granular flows is numerically difficult, particularly in systems where dilute and dense regions occur at the same time and interac

C. P. Burgess, B. P. Dolan

Low-energy transport measurements in Quantum Hall systems have been argued to be governed by emergent modular symmetries whose predictions are robust against many of the detailed microscopic dynamics. We propose the recently-observed quantum Hall effect in graphene as a test of these ideas, and identify to this end a class of predictions for graphene which w

Satoshi Sakai, Katsuhiro Nishinari, Shinji Iida

A general stochastic traffic cellular automaton (CA) model, which includes slow-to-start effect and driver&#39;s perspective, is proposed in this paper. It is shown that this model includes well known traffic CA models such as Nagel-Schreckenberg model, Quick-Start model, and Slow-to-Start model as specific cases. Fundamental diagrams of this new model clear

Weidong Li

We present analytical stationary solutions for the Gross-Pitaevskii equation (GPE) of a Bose-Einstein condensate (BECs) trapped in a double-well potential. These solutions are compared with those described by [Mahmud et al., PRA \textbf{66}, 063607 (2002)]. In particular, we provide further evidence that symmetry preserving stationary solutions can be reduce

WeiDong Li, Jie Liu

In the present paper we investigate the influence of measurements on the quantum dynamics of degenerate Bose atoms gases in a symmetric double-well. We show that continuous measurements enhance asymmetry on the density distribution of the atoms and broaden the parameter regime for self-trapping. We term this phenomenon as nonlinear quantum Zeno effect in ana

J. L. Donley, G. H. Rieke, P. G. Perez-Gonzalez, J. R. Rigby

We present the results of a Spitzer search for obscured AGN in the Chandra Deep Field-North, using both radio-excess and mid-infrared power-law selection. AGN selected via the former technique tend to lie at z ~ 1, have SEDs dominated by the 1.6 micron stellar bump, and have Seyfert-like X-ray luminosities (when detected in the X-ray). In contrast, the IRAC

Jakob Jonsson, Tomas Dahlen, Ariel Goobar, Edvard Mortsell

The flux from distant type Ia supernovae (SN) is likely to be amplified or de-amplified by gravitational lensing due to matter distributions along the line-of-sight. A gravitationally lensed SN would appear brighter or fainter than the average SN at a particular redshift. We estimate the magnification of 26 SNe in the GOODS fields and search for a correlatio

K. -I. Nishikawa, Y. Mizuno, M. Watson, P. Hardee

We investigate jet formation in black-hole systems using 3-D General Relativistic Particle-In-Cell (GRPIC) and 3-D GRMHD simulations. GRPIC simulations, which allow charge separations in a collisionless plasma, do not need to invoke the frozen condition as in GRMHD simulations. 3-D GRPIC simulations show that jets are launched from Kerr black holes as in 3-D

I. Marquez, O. Gonzalez-Martin, J. Masegosa, M. A. Guerrero

The analysis of the X-ray data for a sample of 51 LINER nuclei with available X-ray Chandra imaging is reported. Our aim was to investigate the physical mechanisms which power LINER nuclear activity. The use of multiwavelenght information at radio, UV, optical HST and X-ray lead us to conclude that at least 60% of the LINERs are hosting a low luminosity AGN

M. Thiam, G. A. Wade, F. LeBlanc, V. R. Khalack

We present the results of a study of the photospheric abundances of the HgMn star HD 175640, conducted using archival ESO-UVES spectra. A large number of unblended (titanium, chromium, manganese and iron) lines were studied to search for the presence of chemical stratification in the atmosphere of this star. The selected lines are located in the visible regi

Wan Yan Wong, Douglas Scott

Leung, Chan & Chu (2004) claimed that a previously neglected reheating effect makes a small but noticeable change to the process of cosmological recombination. We revisit this effect by considering a system consisting of both radiation and ionizing gas under adiabatic expansion. In the thermal equilibrium limit, due to the huge radiation background, only a f

David A. Minton, Renu Malhotra

A moderately massive early Sun has been proposed to resolve the so-called faint early Sun paradox. We calculate the time-evolution of the solar mass that would be required by this hypothesis, using a simple parametrized energy-balance model for Earth&#39;s climate. Our calculations show that the solar mass loss rate would need to have been 2-3 orders of magn

Davide Lazzati, Brian J. Morsony, Mitchell C. Begelman

It is now generally accepted that long gamma-ray bursts are associated with the final evolutionary stages of massive stars. As a consequence, their jets must propagate through the stellar progenitor and break out on their surface, before they can reach the photospheric radius and produce the gamma-ray photons. We investigate the role of the progenitor star i

A. L. Longinotti, S. Bianchi, M. Guainazzi, J. Roa-Llamazares

The detection of X-ray narrow spectral features in the 5-7 keV band is becoming increasingly more common in AGN observations, thanks to the capabilities of current X-ray satellites. Such lines, both in emission and in absorption, are mostly interpreted as arising from Iron atoms. When observed with some displacement from their rest frame position, these line

Nikos Prantzos

The concept of Galactic Habitable Zone (GHZ) was introduced a few years ago as an extension of the much older concept of Circumstellar Habitable Zone. However, the physical processes underlying the former concept are hard to identify and even harder to quantify. That difficulty does not allow us, at present, to draw any significant conclusions about the exte

A. L. Longinotti, S. Sim, K. Nandra, M. Cappi

The analysis of hard X-ray features in XMM-Newton data of the bright Sy 1 galaxy Mrk 335 is reported here. The presence of a broad, ionised iron K alpha emission line in the spectrum, first found by Gondoin et al.(2002), is confirmed. The broad line can be modeled successfully by relativistic accretion disc reflection models. Regardless of the underlying con

E. Schinnerer, V. Smolcic, C. L. Carilli, M. Bondi

The VLA-COSMOS large project is described and its scientific objective is discussed. We present a catalog of ~ 3,600 radio sources found in the 2deg^2 COSMOS field at 1.4 GHz. The observations in the VLA A and C configuration resulted in a resolution of 1.5''x1.4'' and a mean rms noise of ~ 10.5(15) uJy/beam in the central 1(2)deg^2. 80 radio sources are cle

A. Pollo, L. Guzzo, O. Le Fevre, B. Meneux

We have investigated the dependence of galaxy clustering on their intrinsic luminosities at z ~ 1, using the data from the First Epoch VIMOS-VLT Deep Survey (VVDS). We have measured the projected two-point correlation function of galaxies, w_p(r_p), for a set of volume-limited samples at an effective redshift <z>=0.9 and median absolute magnitude -19.6< M_B

Jorge Casares

Radial velocity studies of X-ray binaries provide the most solid evidence for the existence of stellar-mass black holes. We currently have 20 confirmed cases, with dynamical masses in excess of 3 Msun. Accurate masses have been obtained for a subset of systems which gives us a hint at the mass spectrum of the black hole population. This review summarizes the

G. Hasinger, N. Cappelluti, H. Brunner, M. Brusa

We present the first set of XMM-Newton EPIC observations in the 2 square degree COSMOS field. The strength of the COSMOS project is the unprecedented combination of a large solid angle and sensitivity over the whole multiwavelength spectrum. The XMM-Newton observations are very efficient in localizing and identifying active galactic nuclei (AGN) and clusters

Asmus Boehm, Lutz Wisotzki, the GEMS team

It is still a matter of debate whether the properties of galaxies hosting an Active Galactic Nucleus (AGN) are different from the properties of quiescent galaxies. We constructed a sample of ~50 AGN at a mean redshift of <z>~0.6 that lack a detectable optical nucleus. This characteristic allows to study the properties of the host galaxies with much higher ac

Brent Groves

I present a broad overview of modelling of the Narrow Line Region (NLR) of active galaxies, and discuss some of the more recent models we currently have for the emission from the NLR. I show why the emission line ratios from the NLR are constrained to certain observed values, and describe what physical parameters we can derive from observations using emissio

R. Aurich, S. Lustig, F. Steiner, H. Then

The low multipoles of the cosmic microwave background (CMB) anisotropy possess some strange properties like the alignment of the quadrupole and the octopole, and the extreme planarity or the extreme sphericity of some multipoles, respectively. In this paper the CMB anisotropy of several multi-connected space forms is investigated with respect to the maximal

P. Buyle, E. Van Hese, S. De Rijcke, H. Dejonghe

We present a method to investigate the radial stability of a spherical anisotropic system that hosts a central supermassive black hole (SBH). Such systems have never been tested before for stability, although high anisotropies have been considered in the dynamical models that were used to estimate the masses of the central putative supermassive black holes.

N. Scoville, H. Aussel, M. Brusa, P. Capak

The Cosmic Evolution Survey (COSMOS) is designed to probe the correlated evolution of galaxies, star formation, active galactic nuclei (AGN) and dark matter (DM) with large-scale structure (LSS) over the redshift range z $> 0.5 $ to 6. The survey includes multi-wavelength imaging and spectroscopy from X-ray to radio wavelengths covering a 2 $\sq$°area, inclu

S. Sawada-Satoh, P. T. P. Ho, S. Muller, S. Matsushita

We present 12CO (J=2-1) observations towards the central region of the Seyfert 2 galaxy NGC 4258 with the Submillimeter Array (SMA). Our interferometric maps show two arm-like elongated components along the major axis of the galaxy, with no strong nuclear concentration. The CO (2-1) morphology and kinematics are similar to previous CO (1-0) results. The velo

M. Suzuki, N. Kawai, T. Tamagawa, A. Yoshida

A class of low-mass X-ray binary sources are known to be both X-ray burst sources and millisecond pulsars at the same time. A new source of this class was discovered by High Energy Transient Explorer 2 (HETE-2) on 14 June 2005 as a source of type-I X-ray bursts, which was named HETE J1900.1-2455. Five X-ray bursts from HETE J1900.1-2455 were observed during

D. Shulyak, G. Valyavin, O. Kochukhov, B. -C. Lee

Several dynamical processes may induce considerable electric currents in the atmospheres of magnetic chemically peculiar (CP) stars. The Lorentz force, which results from the interaction between the magnetic field and the induced currents, modifies the atmospheric structure and induces characteristic rotational variability of the hydrogen Balmer lines. To st

M. C. Begelman, J. E. Pringle

Simulations and analytic arguments suggest that the turbulence driven by magnetorotational instability (MRI) in accretion discs can amplify the toroidal (azimuthal) component of the magnetic field to a point at which magnetic pressure exceeds the combined gas + radiation pressure in the disc. Arguing from the recent analysis by Pessah and Psaltis, and other

M. Krips, A. Eckart, R. Neri, T. Bertram

We present CO(1-0) and CO(2-1) line emission maps of the barred spiral active galaxy HE1029-1831 (z=0.0403) obtained with the IRAM Plateau de Bure Interferometer (PdBI) and in part by the Berkeley-Illinois-Maryland Association (BIMA) observatory. The CO emission is well associated with the optical bar and extended along it. The FWHM of the CO emission is est

S. Kafka, S. B. Howell, R. K. Honeycutt, J. W. Robertson

We present orbit-resolved spectroscopic and photometric observations of the polar ST LMi during its recent low and high states. In the low state spectra, we report the presence of blue and red satellites to the H-alpha emission line; the velocities and visibility of the satellites vary with phase. This behavior is similar to emission line profile variations

Lin Yan, Anna Sajina, Dario Fadda, Phil Choi

We present the mid-infrared (MIR) spectra obtained with the Spitzer InfraRed Spectrograph (IRS) for a sample of 52 sources, selected as infrared luminous, z>1 candidates in the Extragalactic First Look Survey (XFLS). The sample selection criteria are f(24um) > 0.9mJy, nu fnu(24um)/nu fnu(8um) > 3.16 and nu fnu(24um)/nu fnu(0.7um) > 10. Of the 52 spectra, 47

Y. Taniguchi, N. Scoville, T. Murayama, D. B. Sanders

We present deep optical imaging observations of 2 square degree area, covered by the Cosmic Evolution Survey (COSMOS), made by the prime-focus Camera (Supreme-Cam) on the 8.2m Subaru Telescope. Observations were done in six broad-band [B (4459.7 AA), g&#39; (4723.1 AA), V (5483.8 AA), r&#39; (6213.0 AA), i&#39; (7640.8 AA), z&#39; (8855.0 AA)], and one narro

D. D. Frederiks, S. V. Golenetskii, V. D. Palshin, R. L. Aptekar

We analyze the data obtained when the Konus-Wind gamma-ray spectrometer detected a giant flare in SGR 1806-20 on December 27, 2004. The flare is similar in appearance to the two known flares in SGR 0526-66 and SGR 1900+14 while exceeding them significantly in intensity. The enormous X-ray and gamma-ray flux in the narrow initial pulse of the flare leads to a

Alexey V. Gorshkov, Axel Andre, Mikhail D. Lukin, Anders S. Sorensen

In a recent paper [Gorshkov et al., Phys. Rev. Lett. 98, 123601 (2007)] and in the two preceding papers [Gorshkov et al., Phys. Rev. A 76, 033804 (2007); 76, 033805 (2007)], we used a universal physical picture to optimize and demonstrate equivalence between a wide range of techniques for storage and retrieval of photon wave packets in homogeneously broadene

Alexey V. Gorshkov, Axel Andre, Mikhail D. Lukin, Anders S. Sorensen

In a recent paper [Gorshkov et al., Phys. Rev. Lett. 98, 123601 (2007)], we presented a universal physical picture for describing a wide range of techniques for storage and retrieval of photon wave packets in Lambda-type atomic media in free space, including the adiabatic reduction of the photon group velocity, pulse-propagation control via off-resonant Rama

R. P. Hardikar, R. T. Clay

The Hubbard-Holstein model is one of the simplest to incorporate both electron-electron and electron-phonon interactions. In one dimension at half filling the Holstein electron-phonon coupling promotes onsite pairs of electrons and a Peierls charge density wave while the Hubbard onsite Coulomb repulsion U promotes antiferromagnetic correlations and a Mott in

Alexey V. Gorshkov, Axel Andre, Mikhail D. Lukin, Anders S. Sorensen

In a recent paper [Gorshkov et al., Phys. Rev. Lett. 98, 123601 (2007)], we used a universal physical picture to optimize and demonstrate equivalence between a wide range of techniques for storage and retrieval of photon wave packets in Lambda-type atomic media in free space, including the adiabatic reduction of the photon group velocity, pulse-propagation c

W. W. Tian, Z. Li, D. A. Leahy, Q. D. Wang

The recently discovered extended TeV source HESS J1834-087 is associated with both a diffuse X-ray enhancement and a molecular cloud, projected at the center of an old radio supernova remnant G23.3-0.3 (SNR W41). New HI observations from the VLA Galactic Plane Survey (VGPS) show unambiguous structures associated with W41 in the radial velocity range of 53 to

Ashwin S. Pande

We study topological T-duality for spaces with a semi-free $S^1-$action with isolated fixed points. Physically, these correspond to spacetimes containing Kaluza-Klein monopoles. We demonstrate that the physical dyonic coordinate of such spaces has an analogue in our formalism. By analogy with the Dirac monopole, we study these spaces as gerbes. We study the

F. C. Alcaraz, V. Rittenberg

The raise and peel model describes the stochastic model of a fluctuating interface separating a substrate covered with clusters of matter of different sizes, and a rarefied gas of tiles. The stationary state is obtained when adsorption compensates the desorption of tiles. This model is generalized to an interface with defects (D). The defects are either adja

Conrad Creel, Sam Nelson

A method of computing a basis for the second Yang-Baxter cohomology of a finite biquandle with coefficients in Q and Z_p from a matrix presentation of the finite biquandle is described. We also describe a method for computing the Yang-Baxter cocycle invariants of an oriented knot or link represented as a signed Gauss code. We provide a URL for our Maple impl

Paul Fendley, Kareljan Schoutens

We show how to couple two free-fermion chains so that the excitations consist of Cooper pairs with zero energy, and free particles obeying (mutual) exclusion statistics. This behavior is reminiscent of anyonic superconductivity, and of a ferromagnetic version of the Haldane-Shastry spin chain, although here the interactions are local. We solve this model usi

Justin A. Brown, V. Lakshmibai

For the toric variety X associated to the Bruhat poset of Schubert varieties in the Grassmannian, we describe the singular locus in terms of the faces of the associated polyhedral cone. We also determine the tangent cones at the maximal singularities of X. These turn out to be again toric varieties. In the case of X being associated to the Bruhat poset of Sc

W. A. Zuniga-Galindo

We construct and study a fundamental solution of Cauchy&#39;s problem for p-adic parabolic equations of a certain the type. The fundamental solution is the transition density of a p-adic Markov process.

Alain Albouy

We present the theory of tensors with Young tableau symmetry as an efficient computational tool in dealing with the polynomial first integrals of a natural system in classical mechanics. We relate a special kind of such first integrals, already studied by Lundmark, to Beltrami&#39;s theorem about projectively flat Riemannian manifolds. We set the ground for

Vasiliy Dolgushev

We consider a smooth Poisson affine variety with the trivial canonical bundle over complex numbers. For such a variety the deformation quantization algebra A_h enjoys the conditions of the Van den Bergh duality theorem and the corresponding dualizing module is determined by an outer automorphism of A_h intrinsic to A_h. We show how this automorphism can be e

Richard Easther, John T. Giblin, Eugene A. Lim

We consider gravitational wave production due to parametric resonance at the end of inflation, or ``preheating&#39;&#39;. This leads to large inhomogeneities which source a stochastic background of gravitational waves at scales inside the comoving Hubble horizon at the end of inflation. We confirm that the present amplitude of these gravitational waves need

Howard J. Schnitzer

In hep-th/0402219 we considered large N zero-coupling d-dimensional U(N) gauge theories, with N_f matter fields in the fundamental representation on a compact spatial manifold S^{d-1}x time, with N_f/N finite. This class of theories undergo a 3rd order deconfinement transition. As a consequence it was proposed that the dual string theory has a 3rd order phas

R. B. A. Adamson, P. S. Turner, M. W. Mitchell, A. M. Steinberg

We present a method for describing and characterizing the state of N particles that may be distinguishable in principle but not in practice due to experimental limitations. The technique relies upon a careful treatment of the exchange symmetry of the state among experimentally accessible and experimentally inaccessible degrees of freedom. The approach we pre

Mark A. Rubin, Sumanth Kaushik

The presence of loss limits the precision of an approach to phase measurement using maximally entangled states, also referred to as NOON states. A calculation using a simple beam-splitter model of loss shows that, for all nonzero values L of the loss, phase measurement precision degrades with increasing number N of entangled photons for N sufficiently large.

Yangsen Yao, Q. Daniel Wang

Diffuse hot gas can be traced effectively by its X-ray absorption and emission. We present a joint-analysis of these tracers to characterize the spatial and temperature distributions of the Galactic hot gas along the sight-line toward the nearby bright active galactic nucleus Mrk 421. We also complement this analysis with far-UV OVI absorption observations.

Yoav Achiman

A scenario is suggested for spontaneous CP violation in non-SUSY and SUSY SU(10). The idea is to have a scalar potential which generates spontaneously a phase, at the high scale, in the VEV that gives a mass to the RH neutrinos. The case of the minimal renormalizable SUSY SO(10) is discussed in detail. The high scale CP breaking induces a phase in the CKM ma

Dan Hooper, Gabrijela Zaharijas

There are compelling reasons to think that new physics will appear at or below the TeV-scale. It is not known what form this new physics will take, however. Although The Large Hadron collider is very likely to discover new particles associated with the TeV-scale, it may be difficult for it to determine the nature of those particles, whether superpartners, Ka

Juan Maldacena, Ian Swanson

We consider a particular large-radius limit of the worldsheet $S$-matrix for strings propagating on $AdS_5 \times S^5$. This limiting theory interpolates smoothly between the so-called plane-wave and giant-magnon regimes of the theory. The sigma model in this region simplifies; it stands as a toy model of the full theory, and may be easier to solve directly.

Qijin Chen, Chih-Chun Chien, Yan He, K. Levin

We present a pairing fluctuation theory which self-consistently incorporates finite momentum pair excitations in the context of BCS--Bose-Einstein condensation (BEC) crossover, and we apply this theory to high $T_c$ superconductors and ultracold Fermi gases. There are strong similarities between Fermi gases in the unitary regime and high Tc superconductors.

N. A. Sinitsyn, Ilya Nemenman

We study a classical two-state stochastic system in a sea of substrates and products (absorbing states), which can be interpreted as a single Michaelis-Menten catalyzing enzyme or as a channel on a cell surface. We introduce a novel general method and use it to derive the expression for the full counting statistics of transitions among the absorbing states.

Johan Nilsson, H. -P. Eckle, Henrik Johannesson

We consider an integrable model of a one-dimensional mesoscopic ring with the conduction electrons coupled by a spin exchange to a magnetic impurity. A symmetry analysis based on a Bethe Ansatz solution of the model reveals that the current is insensitive to the presence of the impurity. We argue that this is true for any integrable impurity-electron interac

K. Qiao, M. Benesh, T. W. Hyde

The formation of three-dimensional (3D) dust clusters within a complex plasma modeled as a spatially confined Yukawa system is simulated using the box_tree code. Similar to unscreened Coulomb clusters, the occurrence of concentric shells with characteristic occupation numbers was observed. Both the occupation numbers and radii were found to depend on the Deb

Duncan A. Brown, Jeandrew Brink, Hua Fang, Jonathan R. Gair

We explore the prospects for Advanced LIGO to detect gravitational waves from neutron stars and stellar mass black holes spiraling into intermediate-mass ($M\sim 50 M_\odot$ to $350 M_\odot$) black holes. We estimate an event rate for such \emph{intermediate-mass-ratio inspirals} (IMRIs) of up to $\sim 10$--$30 \mathrm{yr}^{-1}$. Our numerical simulations sh

Klaus Hornberger

It is shown how S-matrix theory and the concept of continuous quantum measurements can be combined to yield Markovian master equations which describe the environmental interaction non-perturbatively. The method is then applied to obtain the master equation for the effects of a gas on the internal dynamics of an immobile complex quantum system, such as a trap