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Oct 24, 2014
10/14

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Minaev, Boris; Lindgren, Mikael

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This article is from Sensors (Basel, Switzerland) , volume 9 . Abstract Bis-MPA dendron-coated free-base tetraphenylporphyrin and zinc-tetraphenyl-porphyrin (TPPH2 and TPPZn) were studied in comparison with simple porphyrins (H2P, ZnP) by theoretical simulation of their infrared, Raman and electronic absorption spectra, as well as fluorescense emission. Infrared and fluorescence spectra of the dendrimers were measured and interpreted along with time-resolved measurements of the fluorescence....

Source: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3345821

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Oct 25, 2014
10/14

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Koodaryan, Roodabeh; Rafighi, Ali; Hafezeqoran, Ali

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This article is from Journal of Dental Research, Dental Clinics, Dental Prospects , volume 3 . Abstract Background and aims: Class III malocclusions are considered complex and difficult orthodontic problems to diagnose and treat. The purpose of this study was to investigate the morphologic characteristics of the craniofacial complex of adults with Class III malocclusion in an Iranian population. Materials and methods: Lateral cephalometric radiographs of 50 patients with Class III malocclusion...

Source: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3517198

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Oct 29, 2014
10/14

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Smith, J; Baer, L; Blank, S; Dilawari, A; Carapetyan, K; Alvear, M; Utate, M; Curtin, J; Muggia, F

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This article is from ecancermedicalscience , volume 3 . Abstract Introduction: We describe a screening and prevention programme primarily targeting under-served minority women at high risk of breast and/or ovarian cancer. Women attending this Bellevue Hospital Center (BHC) Clinic were either self-referred from a variety of special outreach programmes or referred internally by medical professionals caring for relatives or friends. Our objective was to delineate referral sources and preliminary...

Source: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3224011

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Oct 28, 2014
10/14

by
Razi, Tahmine; Moslemzade, Seyed Hosein; Razi, Sedighe

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This article is from Journal of Dental Research, Dental Clinics, Dental Prospects , volume 3 . Abstract Background and aims: Panoramic radiography is a method widely used because of low absorbed dose in patients (ap-proximately 10 times less than that in the full mouth survey), reasonable cost and time. Disadvantages of this radiography technique are magnification and distortion as a result of unequal magnification, which can influence dimensional and angular measurements used in clinical...

Source: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3517203

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Sep 22, 2013
09/13

by
Sergio Gomez; Pablo Jensen; Alex Arenas

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We present a reformulation of modularity that allows the analysis of the community structure in networks of correlated data. The new modularity preserves the probabilistic semantics of the original definition even when the network is directed, weighted, signed, and has self-loops. This is the most general condition one can find in the study of any network, in particular those defined from correlated data. We apply our results to a real network of correlated data between stores in the city of...

Source: http://arxiv.org/abs/0812.3030v2

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Sep 23, 2013
09/13

by
M. Battaglia; L. Fletcher; A. O. Benz

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In the classical flare picture, hard X-ray emission from the chromosphere is succeeded by soft-X-ray emission from hot plasma in the flare loop, the soft X-ray emission being a direct consequence of the impact of the non-thermal particle beam. However, observations of events exist in which a pronounced increase in soft X-ray emission is observed minutes before the onset of the hard X-ray emission. Such pre-flare emission clearly contradicts the classical flare picture. For the first time, the...

Source: http://arxiv.org/abs/0903.2754v1

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Sep 23, 2013
09/13

by
Babak Vakili

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The effects of noncommutativity and deformed Heisenberg algebra on the evolution of a two dimensional minisuperspace quantum cosmological model are investigated.

Source: http://arxiv.org/abs/0903.2789v1

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Sep 23, 2013
09/13

by
A. Morozov; Sh. Shakirov

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The simplest partition function, associated with homogeneous symmetric forms S of degree r in n variables, is integral discriminant J_{n|r}(S) = \int e^{-S(x_1 ... x_n)} dx_1 ... dx_n. Actually, S-dependence remains the same if e^{-S} in the integrand is substituted by arbitrary function f(S), i.e. integral discriminant is a characteristic of the form S itself, and not of the averaging procedure. The aim of the present paper is to calculate J_{n|r} in a number of non-Gaussian cases. Using Ward...

Source: http://arxiv.org/abs/0903.2595v1

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Sep 23, 2013
09/13

by
Helmut Satz

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Quantum chromodynamics predicts that the interaction between its fundamental constituents, quarks and gluons, can lead to different states of strongly interacting matter, dependent on its temperature and baryon density. We first survey the possible states of matter in QCD and discuss the transition from a color-confining hadronic phase to a plasma of deconfined colored quarks and gluons. Next, we summarize the results from non-perturbative studies of QCD at finite temperature and baryon...

Source: http://arxiv.org/abs/0903.2778v1

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Sep 23, 2013
09/13

by
K. Sakkos; J. Casulleras; J. Boronat

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High order actions proposed by Chin have been used for the first time in path integral Monte Carlo simulations. Contrarily to the Takahashi-Imada action, which is accurate to fourth order only for the trace, the Chin action is fully fourth order, with the additional advantage that the leading fourth and sixth order error coefficients are finely tunable. By optimizing two free parameters entering in the new action we show that the time step error dependence achieved is best fitted with a sixth...

Source: http://arxiv.org/abs/0903.2763v1

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Sep 23, 2013
09/13

by
Cosmo Lupo; Vittorio Giovannetti; Stefano Mancini

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We introduce a general model for a lossy bosonic memory channel and calculate the classical and the quantum capacity, proving that coherent state encoding is optimal. The use of a proper set of collective field variables allows to unravel the memory, showing that the n-fold concatenation of the memory channel is unitarily equivalent to the direct product of n single-mode lossy bosonic channels.

Source: http://arxiv.org/abs/0903.2764v1

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Sep 23, 2013
09/13

by
Arie Leizarowitz

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The paper is concerned with estimating the number of integers smaller than $x$ whose largest prime divisor is smaller than $y$, denoted $\psi (x,y)$. Much of the related literature is concerned with approximating $\psi (x,y)$ by Dickman's function $\rho (u)$, where $u=\ln x/\ln y$. A typical such result is that $$ \psi (x,y)=x\rho (u)(1+o(1)) \eqno (1) $$ in a certain domain of the parameters $x$ and $y$. In this paper a different type of approximation of $\psi (x,y)$, using iterated logarithms...

Source: http://arxiv.org/abs/0903.2712v1

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Sep 23, 2013
09/13

by
Frans Snik

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Many objects on the sky exhibit a centrosymmetric polarization pattern, particularly in cases involving single scattering around a central source. Utilizing a novel liquid crystal device (the ``theta cell'') that transforms the coordinate system of linear polarization in an image plane from Cartesian to polar, the observation of centrosymmetric polarization patterns can be improved: instead of measuring Stokes Q and U on the sky, one only needs to measure Stokes Q' in the new instrument...

Source: http://arxiv.org/abs/0903.2734v1

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Sep 23, 2013
09/13

by
T. Fujita; M. B. A. Jalil; S. G. Tan

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A semi-classical description of the intrinsic spin-Hall effect (SHE) is presented which is relevant for a wide class of systems. A heuristic model for the SHE is developed, starting with a fully quantum mechanical treatment, from which we construct an intuitive expression for the spin-Hall current and conductivity. Our method makes transparent the physical mechanism which drives the effect, and unifies the SHE across several spintronic and optical systems. Finally, we propose an analogous...

Source: http://arxiv.org/abs/0903.2702v1

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Sep 22, 2013
09/13

by
Andreas Luscher; Andreas Laeuchli

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We study the field dependence of the antiferromagnetic spin-1/2 Heisenberg model on the square lattice by means of exact diagonalizations. In a first part, we calculate the spin-wave velocity, the spin-stiffness, and the magnetic susceptibility and thus determine the microscopic parameters of the low-energy long-wavelength description. In a second part, we present a comprehensive study of dynamical spin correlation functions for magnetic fields ranging from zero up to saturation. We find that...

Source: http://arxiv.org/abs/0812.3420v3

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Sep 23, 2013
09/13

by
Hans-Joachim Baues

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We describe a conjecture on the algebra of higher cohomology operations which leads to the computations of the differentials in the Adams spectral sequence. For this we introduce the notion of an n-th order track category which is suitable to study higher order Toda brackets and the differentials in spectral sequences. We describe various examples of higher order track categories which are topological, in particular the track category of higher cohomology operations. Also differential algebras...

Source: http://arxiv.org/abs/0903.2876v1

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Sep 18, 2013
09/13

by
Martin Lorenz

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Let G be an affine algebraic group and let R be an associative algebra with a rational action of G by algebra automorphisms. We study the induced G-action on the spectrum Spec R of all prime ideals of R, viewed as a topological space with the Jacobson-Zariski topology, and on the subspace consisting of all rational ideals of R. Here, a prime ideal P of R is said to be rational if the extended centroid of R/P is equal to the base field. The main themes of the article are local closedness of...

Source: http://arxiv.org/abs/0809.5205v2

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Sep 23, 2013
09/13

by
G. Hector; E. MacÃas-VirgÃ³s; E. SanmartÃn-CarbÃ³n

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Let $(M,\mathcal{F})$ be a foliated manifold. We prove that there is a canonical isomorphism between the complex of base-like forms $\Omega^*_b(M,\mathcal{F})$ of the foliation and the "De Rham complex" of the space of leaves $M/\mathcal{F}$ when considered as a "diffeological" quotient. Consequently, the two corresponding cohomology groups $H^*_b(M,\mathcal{F})$ and $H^*(M/\mathcal{F})$ are isomorphic.

Source: http://arxiv.org/abs/0903.2871v1

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Sep 21, 2013
09/13

by
A. Yamasaki; S. Imada; K. Takase; T. Muro; Y. Kato; H. Kobori; A. Sugimura; N. Umeyama; H. Sato; Y. Hara; N. Miyakawa; S. I. Ikeda

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We have investigated the electronic structures of newly discovered superconductor FeSe1-x by bulk-sensitive photoemission spectroscopy (PES). The large Fe 3d spectral weight is located in the vicinity of the Fermi level (EF) and it decreases steeply toward EF . Compared with results of band structure calculations, narrowing the Fe 3d band width and the energy shift of the band toward EF are found, suggesting a mass enhancement due to the weak electron correlation effect. Meanwhile, Fe 2p...

Source: http://arxiv.org/abs/0902.3314v3

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Sep 22, 2013
09/13

by
HERA-B Collaboration

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Inclusive doubly differential cross sections d^2\sigma_{pA}/dx_Fdp_T^2 as a function of Feynman-x (x_F) and transverse momentum (p_T) for the production of K^0_s, Lambda^0 and anti-Lambda^0 in proton-nucleus interactions at 920 GeV are presented. The measurements were performed by HERA-B in the negative x_F range (-0.12

Source: http://arxiv.org/abs/0812.0471v2

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Sep 23, 2013
09/13

by
Rainer M. Buchholz; Rainer SchÃ¶del; Andreas Eckart

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The goals of this work are to develop a new method to separate early and late type stellar components of a dense stellar cluster based on narrow band filters, to apply it to the central parsec of the GC, and to conduct a population analysis of this area. We use AO assisted observations obtained at the ESO VLT in the NIR H-band and 7 intermediate bands covering the NIR K-band. A comparison of the resulting SEDs with a blackbody of variable extinction then allows us to determine the presence and...

Source: http://arxiv.org/abs/0903.2135v2

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Sep 21, 2013
09/13

by
A. K. Kwasniewski

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The way to arrive at formula of zeta matrix for any graded posets with the finite set of minimal elements is delivered following the first reference. This is being achieved via adjacency and zeta matrix description of bipartite digraphs chains, the representatives of graded posets. The bipartite digraphs elements of such chains amalgamate to form corresponding cover relation graded poset digraphs with corresponding adjacency matrices being amalgamated throughout natural join as special adequate...

Source: http://arxiv.org/abs/0901.0155v2

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Sep 23, 2013
09/13

by
Alexander John; Andreas Schadschneider; Debashish Chowdhury; Katsuhiro Nishinari

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We report experimental results on unidirectional traffic-like collective movement of ants on trails. Our work is primarily motivated by fundamental questions on the collective spatio-temporal organization in systems of interacting motile constituents driven far from equilibrium. Making use of the analogies with vehicular traffic, we analyze our experimental data for the spatio-temporal organisation of the ants on the trail. From this analysis, we extract the flow-density relation as well as the...

Source: http://arxiv.org/abs/0903.2717v1

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Sep 23, 2013
09/13

by
Y. J. Uemura

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Recent muon and neutron experiments on the new FeAs-based superconductors revealed phase diagrams characterized by first-order evolution from antiferromagnetic to superconducting states, and an inelastic magnetic resonance mode whose energy scales as $\sim 4 k_{B}T_{c}$. These features exhibit striking commonalities with cuprate, backyball, organic, and heavy-fermion superconductors as well as superfluid $^{4}$He.

Source: http://arxiv.org/abs/0903.2758v1

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Sep 18, 2013
09/13

by
Hamid R. Molavian; Michel J. P. Gingras

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Despite a Curie-Weiss temperature $\theta_{\rm CW} \sim -14$ K, the Tb2Ti2O7 pyrochlore magnetic material lacks long range magnetic order down to at least $T^*\approx 50$ mK. It has recently been proposed that the low temperature collective paramagnetic or spin liquid regime of this material may be akin to a spin ice state subject to both thermal and quantum fluctuations $-$ a {\it quantum spin ice} (QSI) of sorts. Here we explore the effect of a magnetic field ${\bm B}$ along the $[111]$...

Source: http://arxiv.org/abs/0809.3477v2

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Sep 23, 2013
09/13

by
Daniel A Spielman; Jaeoh Woo

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Boman and Hendrickson observed that one can solve linear systems in Laplacian matrices in time $\bigO{m^{3/2 + o (1)} \ln (1/\epsilon)}$ by preconditioning with the Laplacian of a low-stretch spanning tree. By examining the distribution of eigenvalues of the preconditioned linear system, we prove that the preconditioned conjugate gradient will actually solve the linear system in time $\softO{m^{4/3} \ln (1/\epsilon)}$.

Source: http://arxiv.org/abs/0903.2816v1

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Sep 23, 2013
09/13

by
Guo-Li Liu

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Topcolor-assisted technicolor (TC2) model predicts the existence of the top-pions and the CP-even top-Higgs with large flavor-changing couplings to the top quark, which at tree-level can mediate the top quark three-body decay t -> cb\bar{b}. In this work we study this decay, showing the dependence of the decay rate on the relevant TC2 parameters and comparing the results with the predictions in the minimal supersymmetric model. We find that the decay rate in the TC2 model is much larger than...

Source: http://arxiv.org/abs/0903.2619v1

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Sep 23, 2013
09/13

by
L. R. Bedin; M. Salaris; G. Piotto; J. Anderson; I. R. King; S. Cassisi

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We use 14 orbits of ACS observations to reach the end of the white-dwarf cooling sequence in the globular cluster M4. Our photometry and completeness tests show that the end is located at magnitude m_F606W = 28.5+/-0.1, which implies an age of 11.6+/-0.6 Gyr (internal errors only). This is consistent with the age from fits to the main sequence turn-off (12.0+/-1.4 Gyr).

Source: http://arxiv.org/abs/0903.2839v1

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Sep 21, 2013
09/13

by
L. Dunne; R. J. Ivison; S. Maddox; M. Cirasuolo; A. M. Mortier; S. Foucaud; E. Ibar; O. Almaini; C. Simpson; R. McLure

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We have studied the uJy radio properties of K-selected galaxies detected in the Ultra-Deep Survey portion of UKIDSS using 610- and 1,400-MHz images from the VLA and GMRT. These deep radio mosaics, combined with the largest and deepest K image currently available, allow high-S/N detections of many K-selected sub-populations, including sBzK and pBzK star-forming and passive galaxies. We find a strong correlation between the radio and K fluxes and a linear relationship between SFR and K...

Source: http://arxiv.org/abs/0808.3139v2

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Sep 23, 2013
09/13

by
Shirley Ho; Simon Dedeo; David Spergel

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We present a new method for detecting the missing baryons by generating a template for the kinematic Sunyaev-Zel'dovich effect. The template is computed from the product of a reconstructed velocity field with a galaxy field; we find that the combination of a galaxy redshift survey such as SDSS and a CMB survey such as ACT and PLANCK can detect the kSZ, and thus the ionized gas, at significant signal-to-noise. Unlike other techniques that look for hot gas or metals, this approach directly...

Source: http://arxiv.org/abs/0903.2845v1

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Sep 18, 2013
09/13

by
Franziska Synatschke; Georg Bergner; Holger Gies; Andreas Wipf

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We study supersymmetric quantum mechanics with the functional RG formulated in terms of an exact and manifestly off-shell supersymmetric flow equation for the effective action. We solve the flow equation nonperturbatively in a systematic super-covariant derivative expansion and concentrate on systems with unbroken supersymmetry. Already at next-to-leading order, the energy of the first excited state for convex potentials is accurately determined within a 1% error for a wide range of couplings...

Source: http://arxiv.org/abs/0809.4396v2

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Sep 22, 2013
09/13

by
Armin LÃ¼hr; Alejandro Saenz

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The stopping power of antiprotons in atomic and molecular hydrogen as well as helium was calculated in an impact-energy range from 1 keV to 6.4 MeV. In the case of H2 and He the targets were described with a single-active electron model centered on the target. The collision process was treated with the close-coupling formulation of the impact-parameter method. An extensive comparison of the present results with theoretical and experimental literature data was performed in order to evaluate...

Source: http://arxiv.org/abs/0812.5058v2

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Sep 23, 2013
09/13

by
FrÃ©dÃ©ric Faure

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We consider a simple model of partially expanding map on the torus. We study the spectrum of the Ruelle transfer operator and show that in the limit of high frequencies in the neutral direction (this is a semiclassical limit), the spectrum develops a spectral gap, for a generic map. This result has already been obtained by M. Tsujii (05). The novelty here is that we use semiclassical analysis which provides a different and quite natural description. We show that the transfer operator is a...

Source: http://arxiv.org/abs/0903.2747v1

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Sep 19, 2013
09/13

by
Andy T. S. Wan; M. H. S. Amin; Shannon X. Wang

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We study the effect of an environment consisting of noninteracting two level systems on Landau-Zener transitions with an interest on the performance of an adiabatic quantum computer. We show that if the environment is initially at zero temperature, it does not affect the transition probability. An excited environment, however, will always increase the probability of making a transition out of the ground state. For the case of equal intermediate gaps, we find an analytical upper bound for the...

Source: http://arxiv.org/abs/cond-mat/0703085v3

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Sep 23, 2013
09/13

by
Jose A. Diaz-Garcia; R. Gutierrez-Jaimez

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Several matrix variate hypergeometric type distributions are derived. The compound distributions of left-spherical matrix variate elliptical distributions and inverted hypergeometric type distributions with matrix arguments are then proposed. The scale mixture of left-spherical matrix variate elliptical distributions and univariate inverted hypergeometric type distributions is also derived as a particular case of the compound distribution approach.

Source: http://arxiv.org/abs/0903.2875v1

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Sep 23, 2013
09/13

by
Susmit Jha; Sanjit A. Seshia; Rhishikesh Limaye

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Satisfiability solvers are increasingly playing a key role in software verification, with particularly effective use in the analysis of security vulnerabilities. String processing is a key part of many software applications, such as browsers and web servers. These applications are susceptible to attacks through malicious data received over network. Automated tools for analyzing the security of such applications, thus need to reason about strings. For efficiency reasons, it is desirable to have...

Source: http://arxiv.org/abs/0903.2825v1

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Sep 23, 2013
09/13

by
Lisa Winter; Richard Mushotzky; Yuichi Terashima; Yoshihiro Ueda

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The fraction of Compton thick sources is one of the main uncertainties left in understanding the AGN population. The Swift Burst Alert Telescope (BAT) all-sky survey, for the first time gives us an unbiased sample of AGN for all but the most heavily absorbed sources (log NH > 25). Still, the BAT spectra (14 - 195 keV) are time-averaged over months of observations and therefore hard to compare with softer spectra from the Swift XRT or other missions. This makes it difficult to distinguish...

Source: http://arxiv.org/abs/0903.2802v1

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Sep 23, 2013
09/13

by
Catalin D. Spataru; Mark S. Hybertsen; Steven G. Louie; Andrew J. Millis

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The Anderson model for a single impurity coupled to two leads is studied using the $GW$ approximation in the strong electron-electron interaction regime as a function of the alignment of the impurity level relative to the chemical potentials in the leads. We employ a non-equilibrium Green's function technique to calculate the electron self-energy, the spin density and the current as a function of bias across the junction. In addition we develop an expression for the change in the expectation...

Source: http://arxiv.org/abs/0903.2683v1

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Sep 23, 2013
09/13

by
L. H. Ford; N. F. Svaiter

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Quantum fluctuations in the density of a fluid with a linear phonon dispersion relation are studied. In particular, we treat the changes in these fluctuations due to non-classical states of phonons and to the presence of boundaries. These effects are analogous to similar effects in relativistic quantum field theory, and we argue that the case of the fluid is a useful analog model for effects in field theory. We further argue that the changes in the mean squared density are in principle...

Source: http://arxiv.org/abs/0903.2694v1

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Sep 23, 2013
09/13

by
Valerie J. Mikles; Peggy Varniere; Stephen S. Eikenberry; Jerome Rodriguez; Dave Rothstein

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It is widely believed that the low frequency quasi-periodic X-ray oscillations observed in microquasars are correlated to, but do not originate at, the physical radius of the inner edge of the accretion disk. Models relating the QPO frequency and color radius are hindered by observations showing contradicting trend correlations between the microquasars GRO 1655-40, XTE J1550-564 and GRS 1915+105. The first shows a negative correlation and the latter two a positive one. By taking into account...

Source: http://arxiv.org/abs/0903.2680v1

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Sep 23, 2013
09/13

by
Carlos Hernandez-Monteagudo; Shirley Ho

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The peculiar motion of ionized baryons is known to introduce temperature anisotropies in the CMB by means of the kinetic Sunyaev-Zel'dovich effect (kSZ). In this work, we present an all sky computation of angular power spectrum of the temperature anisotropies introduced by kSZ momentum of all baryons in the Universe during and after reionization. In an attempt to study the bulk flows of the missing baryons not yet detected, we address separately the contribution from all baryons in the IGM and...

Source: http://arxiv.org/abs/0903.2814v1

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Sep 23, 2013
09/13

by
N. N. Nikolaev; V. R. Zoller

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One of the well known effects of the asymptotic freedom is splitting of the leading-$\log$ BFKL pomeron into a series of isolated poles in complex angular momentum plane. Following our earlier works we explore the phenomenological consequences of the emerging BFKL-Regge factorized expansion for the small-$x$ charm ($F_2^c$) and beauty ($F_{2}^{b}$) structure functions of the proton. As we found earlier,the color dipole approach to the BFKL dynamics predicts uniquely decoupling of subleading...

Source: http://arxiv.org/abs/0903.2729v1

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Sep 23, 2013
09/13

by
Brendon W. Lovett; Ahsan Nazir

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Coherence is a familiar concept in physics: It is the driving force behind wavelike phenomena such as the diffraction of light. Moreover, wave-particle duality implies that all quantum objects can exhibit coherence, and this quantum coherence is crucial to understanding the behaviour of a plethora of systems. In this article, which is written at an undergraduate level, we shall briefly introduce what is meant by coherence in a well-known classical setting, before going on to describe its...

Source: http://arxiv.org/abs/0903.2746v1

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Sep 17, 2013
09/13

by
Tobias Salger; Gunnar Ritt; Carsten Geckeler; Sebastian Kling; Martin Weitz

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We report on experiments studying transport properties of an atomic Bose-Einstein condensate in an optical lattice of spatial period $\lambda/2n$, where $n$ is an integer, realized with the dispersion of multiphoton Raman transitions. We observe Bloch oscillations, as a clear effect of quantum transport, in the sub-wavelength scale periodicity lattice. The unusually strong localisation of atoms is evident from the measured effective mass. Future prospects of the novel lattice structures are...

Source: http://arxiv.org/abs/0711.1772v3

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Sep 20, 2013
09/13

by
Peter K. F. Kuhfittig

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The purpose of this paper is to examine the possible existence or construction of traversable wormholes supported by generalized Chaplygin gas (GCG) by starting with a general line element and the Einstein tensor, together with the equation of state, thereby continuing an earlier study by the author of wormholes supported by phantom energy. Numerical techniques are used to demonstrate the existence of wormhole spacetimes that (1) meet the flare-out conditions at the throat, (2) are traversable...

Source: http://arxiv.org/abs/0802.3656v3

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Sep 21, 2013
09/13

by
Stephan Durr

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A Lie-algebra based recipe for smoothing gauge links in lattice field theory is presented, building on the matrix logarithm. With or without hypercubic nesting, this LOG/HYL smearing yields fat links which are differentiable w.r.t. the original ones. This is essential for defining UV-filtered ("fat link") fermion actions which may be simulated with a HMC-type algorithm. The effect of this smearing on the distribution of plaquettes and on the residual mass of tree-level O(a)-improved...

Source: http://arxiv.org/abs/0709.4110v2

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Sep 23, 2013
09/13

by
Garry W. Angus; Antonaldo Diaferio

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We re-investigate the old problem of the survival of the five globular clusters orbiting the Fornax dwarf galaxy in both standard and modified Newtonian dynamics. For the first time in the history of the topic, we use accurate mass models for the Fornax dwarf, obtained through Jeans modelling of the recently published line of sight velocity dispersion data, and we are also not resigned to circular orbits for the globular clusters. Previously conceived problems stem from fixing the starting...

Source: http://arxiv.org/abs/0903.2874v1

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Sep 23, 2013
09/13

by
J. -F. Desmurs; C. Codella; J. Santiago-Garcia; M. Tafalla; R. Bachiller

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We have performed observations of water maser emission towards a sample of low-mass protostars, in order to investigate the properties of jets associated with the earliest stages of star formation and their interaction with the surrounding medium. The main aim is to measure the absolute positions and proper motions of the H_2O spots in order to investigate the kinematics of the region from where the jet is launched. We imaged the protostars in the nearby region NGC 1333-IRAS 4 in the water...

Source: http://arxiv.org/abs/0903.2770v1

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Sep 21, 2013
09/13

by
Nikolay Gromov; Vladimir Kazakov; Pedro Vieira

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We present a set of functional equations defining the anomalous dimensions of arbitrary local single trace operators in planar N=4 SYM theory. It takes the form of a Y-system based on the integrability of the dual superstring sigma-model on the AdS_5xS^5 background. This Y-system passes some very important tests: it incorporates the full asymptotic Bethe ansatz at large length of operator L, including the dressing factor, and it confirms all recently found wrapping corrections. The recently...

Source: http://arxiv.org/abs/0901.3753v3

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Sep 23, 2013
09/13

by
Frans Snik; Radek Melich; Christoph Keller

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We present the design and the prototype of the Small Synoptic Second Solar Spectrum Telescope (S5T), which can autonomously measure scattering polarization signals on a daily basis with large sensitivity and accuracy. Its data will be used to investigate the nature of weak, turbulent magnetic fields through the Hanle effect in many lines. Also the relation between those fields and the global solar dynamo can be revealed by spanning the observations over a significant fraction of a solar cycle....

Source: http://arxiv.org/abs/0903.2730v1