Skip to main content
Internet Archive's 25th Anniversary Logo

15,559
UPLOADS


More right-solid

More right-solid

Show sorted alphabetically

More right-solid

Show sorted alphabetically

More right-solid

More right-solid
SHOW DETAILS
up-solid down-solid
eye
Title
Date Archived
Creator
Arxiv.org
by A J Aspden; J B Bell; S E Woosley
texts

eye 77

favorite 0

comment 0

In the distributed burning regime, turbulence disrupts the internal structure of the flame, and so the idea of laminar burning propagated by conduction is no longer valid. The nature of the burning depends on the turbulent Damkohler number (Da), which steadily declines from much greater than one to less that one as the density decreases to a few 10^6 g/cc. Scaling arguments predict that the turbulent flame speed s, normalized by the turbulent intensity u, follows s/u=Da^1/2 for Da 1, and that...
Source: http://arxiv.org/abs/1107.2421v1
Arxiv.org
by A J Aspden; J B Bell; S E Woosley
texts

eye 62

favorite 0

comment 0

In previous studies, we examined turbulence-flame interactions in carbon-burning thermonuclear flames in Type Ia supernovae. In this study, we consider turbulence-flame interactions in the trailing oxygen flames. The two aims of the paper are to examine the response of the inductive oxygen flame to intense levels of turbulence, and to explore the possibility of transition to detonation in the oxygen flame. Scaling arguments analogous to the carbon flames are presented and then compared against...
Source: http://arxiv.org/abs/1107.2424v1
Arxiv.org
by A M Cooper-Sarkar
texts

eye 61

favorite 0

comment 0

The PDF4LHC group has benchmarked six modern PDF sets and used them to make predictions for W,Z and Higgs production at the LHC. The reasons why predictions differ are examined and recent updates to the PDFs and their predictions are presented
Source: http://arxiv.org/abs/1107.5170v1
Arxiv.org
by A. -M. S. Tremblay
texts

eye 202

favorite 0

comment 0

Even at weak to intermediate coupling, the Hubbard model poses a formidable challenge. In two dimensions in particular, standard methods such as the Random Phase Approximation are no longer valid since they predict a finite temperature antiferromagnetic phase transition prohibited by the Mermin-Wagner theorem. The Two-Particle-Self-Consistent (TPSC) approach satisfies that theorem as well as particle conservation, the Pauli principle, the local moment and local charge sum rules. The self-energy...
Source: http://arxiv.org/abs/1107.1534v2
Arxiv.org
by A. -M. Uimonen; E. Khosravi; A. Stan; G. Stefanucci; S. Kurth; R. van Leeuwen; E. K. U. Gross
texts

eye 109

favorite 0

comment 0

We study time-dependent electron transport through an Anderson model. The electronic interactions on the impurity site are included via the self-energy approximations at Hartree-Fock (HF), second Born (2B), GW, and T-Matrix level as well as within a time-dependent density functional (TDDFT) scheme based on the adiabatic Bethe-Ansatz local density approximation (ABALDA) for the exchange correlation potential. The Anderson model is driven out of equilibrium by applying a bias to the leads and its...
Source: http://arxiv.org/abs/1107.0162v2
Arxiv.org
by A. -S. F. Obada; D. A. M. Abo-Kahla; N. Metwally; M. Abdel-Aty
texts

eye 71

favorite 0

comment 0

The speed of computations is investigated by means of the orthogonality speed for a charged qubit interacting with a single cavity field prepared initially in a Fock state or Binomial state. We observe that the rate of the computational speed is related to the number of photons inside the cavity. Moreover, we show that the qubit-field coupling plays an opposite role, where the speed of computations is decreased as the coupling is increased. We suggest using the number of photons in the field as...
Source: http://arxiv.org/abs/1107.1781v1
Arxiv.org
by A. A. Abdo; K. S. Wood; M. E. DeCesar; F. Gargano; F. Giordano; P. S. Ray; D. Parent; A. K. Harding; M. Coleman Miller; D. L. Wood; M. T. Wolff
texts

eye 138

favorite 0

comment 0

One of the main results of the Fermi Gamma-Ray Space Telescope is the discovery of {\gamma}-ray selected pulsars. The high magnetic field pulsar, PSR J0007+7303 in CTA1, was the first ever to be discovered through its {\gamma}-ray pulsations. Based on analysis of 2 years of LAT survey data, we report on the discovery of {\gamma}-ray emission in the off-pulse phase interval at the ~ 6{\sigma} level. The flux from this emission in the energy range E \geq 100 MeV is F_100 =...
Source: http://arxiv.org/abs/1107.4151v1
Arxiv.org
texts

eye 84

favorite 0

comment 0

We present the third-order contributions to the quark-gluon and gluon-quark timelike splitting functions for the evolution of fragmentation functions in perturbative QCD. These quantities have been derived by studying physical evolution kernels for photon- and Higgs-exchange structure functions in deep inelastic scattering and their counterparts in semi-inclusive annihilation, together with constraints from the momentum sum rule and the supersymmetric limit. For this purpose we have also...
Source: http://arxiv.org/abs/1107.2263v1
Arxiv.org
by A. A. Bruen; J. W. P. Hirschfeld; D. L. Wehlau
texts

eye 83

favorite 0

comment 0

Some geometry on non-singular cubic curves, mainly over finite fields, is surveyed. Such a curve has 9,3,1 or 0 points of inflexion, and cubic curves are classified accordingly. The group structure and the possible numbers of rational points are also surveyed. A possible strengthening of the security of elliptic curve cryptography is proposed using a `shared secret' related to the group law. Cubic curves are also used in a new way to construct sets of points having various combinatorial and...
Source: http://arxiv.org/abs/1107.4387v1
Arxiv.org
by A. A. Grib; Yu. V. Pavlov
texts

eye 55

favorite 0

comment 0

Different models of the role of creation of superheavy particles in the early Friedmann Universe with their subsequent decay on light particles are investigated. The observable numbers of baryon and entropy are predicted. The possible role of superheavy particles in creation of cold dark matter is discussed.
Source: http://arxiv.org/abs/gr-qc/0009071v2
Arxiv.org
by A. A. Kaverzin; A. S. Mayorov; A. Shytov; D. W. Horsell
texts

eye 66

favorite 0

comment 0

We experimentally study the effect of different scattering potentials on the flicker noise observed in graphene devices on silica substrates. The noise in nominally identical devices is seen to behave in two distinct ways as a function of carrier concentration, changing either monotonically or nonmonotonically. We attribute this to the interplay between long- and short-range scattering mechanisms. Water is found to significantly enhance the noise magnitude and change the type of the noise...
Source: http://arxiv.org/abs/1107.3488v1
Arxiv.org
by A. A. Krutov; A. P. Martynenko
texts

eye 55

favorite 0

comment 0

We present new investigation of the Lamb shift (2P_{1/2}-2S_{1/2}) in muonic deuterium (mu d) atom using the three-dimensional quasipotential method in quantum electrodynamics. The vacuum polarization, nuclear structure and recoil effects are calculated with the account of contributions of orders alpha^3, alpha^4, alpha^5 and alpha^6. The results are compared with earlier performed calculations. The obtained numerical value of the Lamb shift 202.4139 meV can be considered as a reliable estimate...
Source: http://arxiv.org/abs/1107.3080v4
Arxiv.org
texts

eye 84

favorite 0

comment 0

For various one-dimensional quantum liquids in the framework of the Luttinger model (bosonization) we establish the relations between the coefficients before the power-law asymptotics of the correlators (prefactors) and the formfactors of the corresponding local operators. The derivation of these relations in the framework of the bosonization procedure allows to substantiate the prediction for the formfactors corresponding to the low-lying particle-hole excitations. We present an explicit...
Source: http://arxiv.org/abs/1107.4295v3
Arxiv.org
texts

eye 60

favorite 0

comment 0

Self-adjoint boundary problems for the equation $y^{(4)}-\lambda\rho y=0$ with generalized derivative $\rho\in W_2^{-1}[0,1]$ of self-similar Cantor type function as a weight are considered. Using the oscillating properties of the eigenfunctions, the spectral asymptotics are made more precise then in previous papers.
Source: http://arxiv.org/abs/1107.4791v1
Arxiv.org
by A. Abada; A. J. R. Figueiredo; J. C. Romao; A. M. Teixeira
texts

eye 72

favorite 0

comment 0

We study the impact of a type-I SUSY seesaw concerning lepton flavour violation (LFV) both at low-energies and at the LHC. The study of the di-lepton invariant mass distribution at the LHC allows to reconstruct some of the masses of the different sparticles involved in a decay chain. In particular, the combination with other observables renders feasible the reconstruction of the masses of the intermediate sleptons involved in $ \chi_2^0\to \tilde \ell \,\ell \to \ell \,\ell\,\chi_1^0$ decays....
Source: http://arxiv.org/abs/1007.4833v2
Arxiv.org
texts

eye 72

favorite 0

comment 0

This paper presents a new classifier combination technique based on the Dempster-Shafer theory of evidence. The Dempster-Shafer theory of evidence is a powerful method for combining measures of evidence from different classifiers. However, since each of the available methods that estimates the evidence of classifiers has its own limitations, we propose here a new implementation which adapts to training data so that the overall mean square error is minimized. The proposed technique is shown to...
Source: http://arxiv.org/abs/1107.0018v1
Arxiv.org
by A. Alexandrov
texts

eye 41

favorite 0

comment 0

We derive exact matrix integral representations for different sums over partitions. The characteristic feature of all obtained matrix models is the presence of logarithmic (or, vice versa, exponential) terms in the potential. Our derivation is based on the application of the higher Casimir operators. The Toda lattice integrability of the basic sums over partitions can be easily derived from the matrix model representation.
Source: http://arxiv.org/abs/1005.5715v3
Arxiv.org
by A. Alvarez-Candal; N. Pinilla-Alonso; J. Licandro; J. Cook; E. Mason; T. Roush; D. Cruikshank; F. Gourgeot; E. Dotto; D. Perna
texts

eye 58

favorite 0

comment 0

X-Shooter is the first second-generation instrument for the ESO-VLT. It as a spectrograph covering the 300 - 2480 nm spectral range at once with a high resolving power. These properties enticed us to observe (136199) Eris during the science verification of the instrument. The target has numerous absorption features in the optical and near-infrared domain which has been observed by different authors, showing differences in their positions and strengths. We attempt at constraining the existence...
Source: http://arxiv.org/abs/1107.1708v1
Arxiv.org
texts

eye 53

favorite 0

comment 0

We present first comparisons between Light Element Primary Process (LEPP) abundances observed in some ultra metal poor (UMP) stars and nucleosynthesis calculations based on long-time hydrodynamical simulations of core-collapse supernovae and their neutrino-driven wind. UMP star observations indicate Z>38 elements include the contributions of at least two nucleosynthesis components: r-process nuclei that are synthesized by rapid neutron capture in a yet unknown site and LEPP elements (mainly...
Source: http://arxiv.org/abs/1007.1275v2
Arxiv.org
by A. B. Goncharov
texts

eye 51

favorite 0

comment 0

The Hodge Galois group is the Tannakian Galois group of the category of real mixed Hodge structures. It has a subgroup, called the twistor Galois group, which is the Galois group of the category of mixed twistor structures, defined by C. Simpson. It is isomorphic to a semidirect product of C* and the unipotent radical of the Hodge Galois group. We define a natural action of the twistor Galois group by A-infinity autoequivalences of the derived category of complexes of sheaves with smooth...
Source: http://arxiv.org/abs/1107.5710v1
Arxiv.org
by A. Balocchi; J. Renard; C. T. Nguyen; B. Gayral; T. Amand; H. Mariette; B. Daudin; G. Tourbot; X. Marie
texts

eye 101

favorite 0

comment 0

We report on the exciton spin dynamics of nanowire embedded GaN/AlN Quantum Dots (QDs) investigated by time-resolved photoluminescence spectroscopy. Under a linearly polarized quasiresonant excitation we evidence the quenching of the exciton spin relaxation and a temperature insensitive degree of the exciton linear polarization, demonstrating the robustness of the optical alignment of the exciton spin in these nanowire embedded QDs. A detailed examination of the luminescence polarization...
Source: http://arxiv.org/abs/1107.5644v1
Arxiv.org
by A. Balocchi; Q. H. Duong; P. Renucci; B. Liu; C. Fontaine; T. Amand; D. Lagarde; X. Marie
texts

eye 39

favorite 0

comment 0

The electron spin dynamics in (111)-oriented GaAs/AlGaAs quantum wells is studied by timeresolved photoluminescence spectroscopy. By applying an external field of 50 kV/cm a two-order of magnitude increase of the spin relaxation time can be observed reaching values larger than 30 ns; this is a consequence of the electric field tuning of the spin-orbit conduction band splitting which can almost vanish when the Rashba term compensates exactly the Dresselhaus one. The measurements under transverse...
Source: http://arxiv.org/abs/1107.5642v1
Arxiv.org
by A. Barreira; P. P. Avelino
texts

eye 45

favorite 0

comment 0

In this paper we compare the performances of the chi-square and median likelihood analysis in the determination of cosmological constraints using type Ia supernovae data. We perform a statistical analysis using the 307 supernovae of the Union 2 compilation of the Supernova Cosmology Project and find that the chi-square statistical analysis yields tighter cosmological constraints than the median statistic if only supernovae data is taken into account. We also show that when additional...
Source: http://arxiv.org/abs/1107.3971v1
Arxiv.org
by A. Bartl; H. Eberl; B. Herrmann; K. Hidaka; W. Majerotto; W. Porod
texts

eye 51

favorite 0

comment 0

We study the effect of squark generation mixing on squark production and decays at LHC in the Minimal Supersymmetric Standard Model (MSSM). We show that the effect can be very large despite the very strong constraints on quark flavour violation (QFV) from experimental data on B mesons. We find that the two lightest up-type squarks su_{1,2} can have large branching ratios for the decays into 'c-quark + neutralino_1' and 't-quark + neutralino_1' at the same time due to squark generation mixing,...
Source: http://arxiv.org/abs/1007.5483v2
Arxiv.org
by A. Bartl; H. Eberl; E. Ginina; B. Herrmann; K. Hidaka; W. Majerotto; W. Porod
texts

eye 79

favorite 0

comment 0

We study the effect of squark generation mixing on gluino production and decays at LHC in the Minimal Supersymmetric Standard Model (MSSM) for the case that the gluino is lighter than all squarks and dominantly decays into three particles, $gl -> q qbar neut_k, gl -> q qbar' char_l$. We assume mixing between the second and the third squark generations in the up-type and down-type squark sectors. We show that this mixing can lead to very large branching ratios of the quark-flavour...
Source: http://arxiv.org/abs/1107.2775v2
Arxiv.org
texts

eye 103

favorite 0

comment 0

We present results on the chiral and deconfinement properties of the QCD transition at finite temperature. We performed calculations using asqtad and HISQ/tree actions using lattices with temporal extent N_tau=6, 8 and 12 allowing to control the approach to the continuum limit. We analyze the chiral transition in terms of universal O(N) scaling functions. From peaks in the scaling functions we perform a simultaneous continuum extrapolation for HISQ/tree and asqtad to derive the critical...
Source: http://arxiv.org/abs/1107.5027v1
Arxiv.org
by A. Belhaj; M. Benhamza; S. E. Ennadifi; S. Nassiri; E. H. Saidi
texts

eye 98

favorite 0

comment 0

Using instanton effects, we discuss the problem of fermion mass hierarchies in an MSSM-like Type IIA orientifolded model with U(3)xSp(1)xU(1)xU(1) gauge symmetry obtained from intersecting D6-branes. In the corresponding four-stack quiver, the different scales of the generated superpotential couplings offer a partial solution to fermion mass hierarchies. Using the known data with neutrino masses m_{v_{\tau}}\lesssim 2 eV, we give the magnitudes of the relevant scales.
Source: http://arxiv.org/abs/1107.0872v1
Arxiv.org
by A. Belhaj; N-E. Fahssi; E. H. Saidi; A. Segui
texts

eye 112

favorite 0

comment 0

We engineer U(1)^n Chern-Simons type theories describing fractional quantum Hall solitons (QHS) in 1+2 dimensions from M-theory compactified on eight dimensional hyper-K\"{a}hler manifolds as target space of N=4 sigma model. Based on M-theory/Type IIA duality, the systems can be modeled by considering D6-branes wrapping intersecting Hirzebruch surfaces F_0's arranged as ADE Dynkin Diagrams and interacting with higher dimensional R-R gauge fields. In the case of finite Dynkin quivers, we...
Source: http://arxiv.org/abs/1007.4485v2
Arxiv.org
by A. Ben-Yair; A. Felner; S. Kraus; N. Netanyahu; R. Stern
texts

eye 169

favorite 0

comment 0

We address the problem of finding the shortest path between two points in an unknown real physical environment, where a traveling agent must move around in the environment to explore unknown territory. We introduce the Physical-A* algorithm (PHA*) for solving this problem. PHA* expands all the mandatory nodes that A* would expand and returns the shortest path between the two points. However, due to the physical nature of the problem, the complexity of the algorithm is measured by the traveling...
Source: http://arxiv.org/abs/1107.0041v1
Arxiv.org
texts

eye 104

favorite 0

comment 0

We present a semi-classical analysis of the opening of superchannels in gated mesoscopic SNS junctions. For perfect junctions (i.e. hard-wall potential), this was considered by Chtchelkatchev, Lesovik and Blatter in the framework of scattering matrices. Here we allow for imperfections in the junction, so that the complex order parameter continues as a smooth function, which is a constant in the superconducting banks, and vanishes rapidly inside the lead. We obtain quantization rules for...
Source: http://arxiv.org/abs/1107.0673v1
Arxiv.org
by A. Beraudo; J. G. Milhano; U. A. Wiedemann
texts

eye 103

favorite 0

comment 0

The suppression of high-pT single-hadron spectra in heavy-ion collisions is usually interpreted as due to parton energy-loss of high-momentum quarks and gluons propagating in the plasma. Here, we discuss to what extent this partonic picture must be complemented by a picture of medium-modified hadronization. In particular, we show how color-exchange with the medium modifies the properties of color singlet-clusters arising from the parton branchings, producing a softening of the hadron spectra.
Source: http://arxiv.org/abs/1107.1080v1
Arxiv.org
by A. Bermudez; F. Jelezko; M. B. Plenio; A. Retzker
texts

eye 79

favorite 0

comment 0

We propose a scheme enabling controlled quantum coherent interactions between separated nitrogen-vacancy centers in diamond in the presence of strong magnetic fluctuations. The proposed scheme couples nuclear qubits employing the magnetic dipole-dipole interaction between the electron spins and, crucially, benefits from the suppression of the effect of environmental magnetic field fluctuations thanks to a strong microwave driving. This scheme provides a basic building block for a full-scale...
Source: http://arxiv.org/abs/1107.2617v2
Arxiv.org
by A. Bertoldi; S. Bernon; T. Vanderbruggen; A. Landragin; P. Bouyer
texts

eye 94

favorite 0

comment 0

We report the precise characterization of the optical potential obtained by injecting a distributed-feedback erbium-doped fiber laser (DFB EDFL) at 1560 nm to the transversal modes of a folded optical cavity. The optical potential was mapped in situ using cold rubidium atoms, whose potential energy was spectrally resolved thanks to the strong differential light shift induced by the 1560 nm laser on the two levels of the probe transition. The optical potential obtained in the cavity is suitable...
Source: http://arxiv.org/abs/1007.2721v2
Arxiv.org
by A. Bonafede; K. Dolag; F. Stasyszyn; G. Murante; S. Borgani
texts

eye 138

favorite 0

comment 0

Magnetic fields in the intra-cluster medium of galaxy clusters have been studied in the past years through different methods. In the next years the up-coming generation of radio telescopes is going to provide new data that have the potential of setting constraints on the properties of magnetic fields in galaxy clusters. Here we present zoomed-in simulations for a set of massive galaxy clusters (M_v > 10^15 M_sun/h). This is an ideal sample to study the evolution of magnetic field during the...
Source: http://arxiv.org/abs/1107.0968v1
Arxiv.org
by A. Borodin; R. El-Yaniv; V. Gogan
texts

eye 75

favorite 0

comment 0

A novel algorithm for actively trading stocks is presented. While traditional expert advice and "universal" algorithms (as well as standard technical trading heuristics) attempt to predict winners or trends, our approach relies on predictable statistical relations between all pairs of stocks in the market. Our empirical results on historical markets provide strong evidence that this type of technical trading can "beat the market" and moreover, can beat the best stock in the...
Source: http://arxiv.org/abs/1107.0036v1
Arxiv.org
by A. C. Aguilar; D. Binosi; J. Papavassiliou
texts

eye 108

favorite 0

comment 0

In this article we derive the integral equation that controls the momentum dependence of the effective gluon mass in the Landau gauge. This is accomplished by means of a well-defined separation of the corresponding "one-loop dressed" Schwinger-Dyson equation into two distinct contributions, one associated with the mass and one with the standard kinetic part of the gluon. The entire construction relies on the existence of a longitudinally coupled vertex of nonperturbative origin, which...
Source: http://arxiv.org/abs/1107.3968v1
Arxiv.org
texts

eye 43

favorite 0

comment 0

We propose to address in a natural manner, the modular variable concept explicitly in a Schr\"odinger picture. The idea of Modular Variables was introduced in 1969 by Aharonov, Pendleton and Petersen to explain certain non-local properties of quantum mechanics. Our approach to this subject is based on Schwinger's finite quantum kinematics and it's continuous limit.
Source: http://arxiv.org/abs/1007.1685v3
Arxiv.org
by A. Caciolli; C. Mazzocchi; V. Capogrosso; D. Bemmerer; C. Broggini; P. Corvisiero; H. Costantini; Z. Elekes; A. Formicola; Zs. Fulop; G. Gervino; A. Guglielmetti; C. Gustavino; Gy. Gyurky; G. Imbriani; M. Junker; A. Lemut; M. Marta; R. Menegazzo; S. Palmerini; P. Prati; V. Roca; C. Rolfs; C. Rossi Alvarez; E. Somorjai; O. Straniero; F. Strieder; F. Terrasi; H. P. Trautvetter; A. Vomiero
texts

eye 48

favorite 0

comment 0

The NO cycle takes place in the deepest layer of a H-burning core or shell, when the temperature exceeds T {\simeq} 30 {\cdot} 106 K. The O depletion observed in some globular cluster giant stars, always associated with a Na enhancement, may be due to either a deep mixing during the RGB (red giant branch) phase of the star or to the pollution of the primordial gas by an early population of massive AGB (asymptotic giant branch) stars, whose chemical composition was modified by the hot bottom...
Source: http://arxiv.org/abs/1107.4514v1
Arxiv.org
by A. Campillo; F. Delgado; S. M. Gusein-Zade
texts

eye 31

favorite 0

comment 0

We offer a new approach to a definition of an equivariant version of the Poincar\'e series. This Poincar\'e series is defined not as a power series, but as an element of the Grothendieck ring of $G$-sets with an additional structure. We compute this Poincar\'e series for natural filtrations on the ring of germs of functions on the plane $(\C^2,0)$ with a finite group representation.
Source: http://arxiv.org/abs/1005.5656v2
Arxiv.org
texts

eye 143

favorite 0

comment 0

For curved projective manifolds we introduce a notion of a normal tractor frame field, based around any point. This leads to canonical systems of (redundant) coordinates that generalise the usual homogeneous coordinates on projective space. These give preferred local maps to the model projective space that encode geometric contact with the model to a level that is optimal, in a suitable sense. In terms of the trivialisations arising from the special frames, normal solutions of classes of...
Source: http://arxiv.org/abs/1005.2246v2
Arxiv.org
by A. Carmona; G. van der Plas; M. E. van den Ancker; M. Audard; L. B. F. M Waters; D. Fedele; B. Acke; E. Pantin
texts

eye 109

favorite 0

comment 0

We report on a sensitive search for H2 1-0 S(1), 1-0 S(0) and 2-1 S(1) ro-vibrational emission at 2.12, 2.22 and 2.25 micron in a sample of 15 Herbig Ae/Be stars employing CRIRES, the ESO-VLT near-infrared high-resolution spectrograph, at R~90,000. We detect the H2 1-0 S(1) line toward HD 100546 and HD 97048. In the other 13 targets, the line is not detected. The H2 1-0 S(0) and 2-1 S(1) lines are undetected in all sources. This is the first detection of near-IR H2 emission in HD 100546. The H2...
Source: http://arxiv.org/abs/1107.1994v1
Arxiv.org
by A. Cavalleri; G. Ciani; R. Dolesi; A. Heptonstall; M. Hueller; D. Nicolodi; S. Rowan; D. Tombolato; S. Vitale; P. J. Wass; W. J. Weber
texts

eye 103

favorite 0

comment 0

We report on residual gas damping of the motion of a macroscopic test mass enclosed in a nearby housing in the molecular flow regime. The damping coefficient, and thus the associated thermal force noise, is found to increase significantly when the distance between test mass and surrounding walls is smaller than the test mass itself. The effect has been investigated with two torsion pendulums of different geometry and has been modelled in a numerical simulation whose predictions are in good...
Source: http://arxiv.org/abs/1107.2520v1
Arxiv.org
by A. Chiuri; V. Rosati; G. Vallone; S. Pádua; H. Imai; S. Giacomini; C. Macchiavello; P. Mataloni
texts

eye 47

favorite 0

comment 0

We present the experimental realization of the optimal estimation protocol for a Pauli noisy channel. The method is based on the generation of 2-qubit Bell states and the introduction of quantum noise in a controlled way on one of the state subsystems. The efficiency of the optimal estimation, achieved by a Bell measurement, is shown to outperform quantum process tomography.
Source: http://arxiv.org/abs/1107.0888v2
Arxiv.org
by A. Costa; U. Becciani; P. Massimino; M. Krokos; G. Caniglia; C. Gheller; A. Grillo; F. Vitello
texts

eye 45

favorite 0

comment 0

This article presents a newly developed Web portal called VisIVOWeb that aims to provide the astrophysical community with powerful visualization tools for large-scale data sets in the context of Web 2.0. VisIVOWeb can effectively handle modern numerical simulations and real-world observations. Our open-source software is based on established visualization toolkits offering high-quality rendering algorithms. The underlying data management is discussed with the supported visualization interfaces...
Source: http://arxiv.org/abs/1107.3053v1
Arxiv.org
texts

eye 91

favorite 0

comment 0

We revisit the standard procedure to match non-perturbative models to perturbative QCD, using experimental data. The strong coupling constant plays a central role in the QCD evolution of parton densities. We will extend this procedure with a non-perturbative generalization of the QCD running coupling and use this new development to understand why perturbative treatments are working reasonably well in the context of hadronic models. Vice versa, this new procedure broadens the ways of analyzing...
Source: http://arxiv.org/abs/1107.4880v1
Arxiv.org
by A. Cucchiara; S. B. Cenko; J. S. Bloom; A. Melandri; A. Morgan; S. Kobayashi; R. J. Smith; D. A. Perley; W. Li; J. L. Hora; R. L. da Silva; J. X. Prochaska; P. A. Milne; N. R. Butler; B. Cobb; G. Worseck; C. G. Mundell; I. A. Steele; A. V. Filippenko; M. Fumagalli; C. R. Klein; A. Stephens; A. Bluck; R. Mason
texts

eye 163

favorite 0

comment 0

Understanding the origin and diversity of emission processes responsible for Gamma-ray Bursts (GRBs) remains a pressing challenge. While prompt and contemporaneous panchromatic observations have the potential to test predictions of the internal-external shock model, extensive multiband imaging has been conducted for only a few GRBs. We present rich, early-time, multiband datasets for two \swift\ events, GRB 110205A and GRB 110213A. The former shows optical emission since the early stages of the...
Source: http://arxiv.org/abs/1107.3352v2
Arxiv.org
by A. Cuoco; A. Sellerholm; J. Conrad; S. Hannestad
texts

eye 134

favorite 0

comment 0

We perform a detailed study of the sensitivity to the anisotropies related to Dark Matter (DM) annihilation in the Isotropic Gamma-Ray Background (IGRB) as measured by the Fermi Large Area Telescope (Fermi-LAT). For the first time, we take into account the effects of the Galactic foregrounds and use a realistic representation of the Fermi-LAT. We consider DM anisotropies of extra-galactic origin and of Galactic origin (which can be generated through annihilation in the Milky Way sub-structures)...
Source: http://arxiv.org/abs/1005.0843v2
Arxiv.org
texts

eye 57

favorite 0

comment 0

The Big Bang predicted theoretically by Friedmann could not be discovered in the 1920th, since global cosmological distances (more than 300-1000 Mpc) were not available for observations at that time. In 1927-29, Lema\^itre and Hubble studied receding motions of galaxies at local distances of less than 20-30 Mpc and found that the motions followed the (nearly) linear velocity-distance relation, known now as Hubble's law. For decades, the real nature of this phenomenon has remained a mystery, in...
Source: http://arxiv.org/abs/1107.5695v1
Arxiv.org
texts

eye 43

favorite 0

comment 0

MAP is the problem of finding a most probable instantiation of a set of variables given evidence. MAP has always been perceived to be significantly harder than the related problems of computing the probability of a variable instantiation Pr, or the problem of computing the most probable explanation (MPE). This paper investigates the complexity of MAP in Bayesian networks. Specifically, we show that MAP is complete for NP^PP and provide further negative complexity results for algorithms based on...
Source: http://arxiv.org/abs/1107.0024v1
Arxiv.org
by A. De Cia; R. L. C. Starling; K. Wiersema; A. J. van der Horst; P. M. Vreeswijk; G. Björnsson; A. de Ugarte Postigo; P. Jakobsson; A. J. Levan; E. Rol; S. Schulze; N. R. Tanvir
texts

eye 96

favorite 0

comment 0

GRB 070125 is among the most energetic bursts detected and the most extensively observed so far. Nevertheless, unresolved issues are still open in the literature on the physics of the afterglow and on the GRB environment. In particular, GRB 070125 was claimed to have exploded in a galactic halo environment, based on the uniqueness of the optical spectrum and the non-detection of an underlying host galaxy. In this work we collect all publicly available data and address these issues by modelling...
Source: http://arxiv.org/abs/1107.3748v1
Arxiv.org
texts

eye 147

favorite 0

comment 0

The electronic properties of a graphene monolayer in a magnetic and a strain-induced pseudo-magnetic field are studied in the presence of spin-orbit interactions (SOI) that are artificially enhanced, e.g., by suitable adatom deposition. For the homogeneous case, we provide analytical results for the Landau level eigenstates for arbitrary intrinsic and Rashba SOI, including also the Zeeman field. The edge states in a semi-infinite geometry are studied in the absence of the Rashba term. For a...
Source: http://arxiv.org/abs/1107.3961v2
Arxiv.org
by A. Dechant; E. Lutz; E. Barkai; D. A. Kessler
texts

eye 73

favorite 0

comment 0

We investigate the diffusion of particles in an attractive one-dimensional potential that grows logarithmically for large $|x|$ using the Fokker-Planck equation. An eigenfunction expansion shows that the Boltzmann equilibrium density does not fully describe the long time limit of this problem. Instead this limit is characterized by an infinite covariant density. This non-normalizable density yields the mean square displacement of the particles, which for a certain range of parameters exhibits...
Source: http://arxiv.org/abs/1107.0884v1
Arxiv.org
by A. Deltuva
texts

eye 67

favorite 0

comment 0

Bosonic dimer-dimer scattering is studied near the unitary limit using momentum-space equations for the four-particle transition operators. The impact of the Efimov effect on the dimer-dimer scattering observables is explored and a number of universal relations is established with high accuracy. The rate for the creation of Efimov trimers via dimer-dimer collisions is calculated.
Source: http://arxiv.org/abs/1107.3956v1
Arxiv.org
by A. Denner; S. Heinemeyer; I. Puljak; D. Rebuzzi; M. Spira
texts

eye 132

favorite 0

comment 0

We present an update of the branching ratios for Higgs-boson decays in the Standard Model. We list results for all relevant branching ratios together with corresponding uncertainties resulting from input parameters and missing higher-order corrections. As sources of parametric uncertainties we include the masses of the charm, bottom, and top quarks as well as the QCD coupling constant. We compare our results with other predictions in the literature.
Source: http://arxiv.org/abs/1107.5909v2
Arxiv.org
by A. Depperschmidt; N. Ketterer; P. Pfaffelhuber
texts

eye 39

favorite 0

comment 0

We study a model for the translocation of proteins across membranes through a nanopore using a ratcheting mechanism. When the protein enters the nanopore it diffuses in and out of the pore according to a Brownian motion. Moreover, it is bound by ratcheting molecules which hinder the diffusion of the protein out of the nanopore, i.e. the Brownian motion is reflected such that no ratcheting molecule exits the pore. New ratcheting molecules bind at rate gamma. Extending our previous approach...
Source: http://arxiv.org/abs/1107.5219v1
Arxiv.org
by A. Dinesh Kumar; Ambedkar Dukkipati
texts

eye 126

favorite 0

comment 0

Low density parity-check (LDPC) codes are a class of linear block codes that are decoded by running belief propagation (BP) algorithm or log-likelihood ratio belief propagation (LLR-BP) over the factor graph of the code. One of the disadvantages of LDPC codes is the onset of an error floor at high values of signal to noise ratio caused by trapping sets. In this paper, we propose a two stage decoder to deal with different types of trapping sets. Oscillating trapping sets are taken care by the...
Source: http://arxiv.org/abs/1107.2867v1
Arxiv.org
texts

eye 95

favorite 0

comment 0

An observable that can be used to better constrain the mechanism responsible for the parton energy loss is the elliptic azimuthal event anisotropy, $v_2$. We report on measurements of $v_2$ for inclusive and identified charged particles in Pb-Pb collisions at $\sqrt{s_{NN}} = 2.76$ TeV recorded by the ALICE experiment at the LHC. $v_2$ is presented for a wide range of particle transverse momentum up to $p_T=20$ GeV/c. The particle $v_2$ is finite, positive and approximately constant for...
Source: http://arxiv.org/abs/1107.0454v1
Arxiv.org
by A. Donini; J. J. Gomez Cadenas; D. Meloni
texts

eye 64

favorite 0

comment 0

We study the contribution of $\nu_e \to \nu_\tau \to \tau \to \mu$ transitions to the wrong-sign muon sample of the {\em golden} channel of the Neutrino Factory. Muons from tau decays are not really a background, since they contain information from the oscillation signal, and represent a small fraction of the sample. However, if not properly handled they introduce serious systematic error, in particular if the detector/analysis are sensitive to muons of low energy. This systematic effect is...
Source: http://arxiv.org/abs/1005.2275v2
Arxiv.org
by A. E. Kaloshin; V. P. Lomov
texts

eye 186

favorite 0

comment 0

We suggest simple method to solve wave equation for Rarita--Schwinger field without additional constraints. This method based on use of off-shell projection operators allows to diagonalize spin-1/2 sector of the field.
Source: http://arxiv.org/abs/1107.4445v1
Arxiv.org
by A. E. Kyprianou; R. -L. Liu; A. Murillo-Salas; Y. -X. Ren
texts

eye 90

favorite 0

comment 0

We consider the classical problem of existence, uniqueness and asymptotics of monotone solutions to the travelling wave equation associated to the parabolic semi-group equation of a super-Brownian motion with a general branching mechanism. Whilst we are strongly guided by the probabilistic reasoning of Kyprianou (2004) for branching Brownian motion, the current paper offers a number of new insights. Our analysis incorporates the role of Seneta-Heyde norming which, in the current setting, draws...
Source: http://arxiv.org/abs/1005.3659v2
Arxiv.org
by A. E. Rodin; Ding Chen
texts

eye 49

favorite 0

comment 0

An algorithm is proposed for constructing a group (ensemble) pulsar time based on the application of optimal Wiener filters. This algorithm makes it possible to separate the contributions of variations of the atomic time scale and of the pulsar rotation to barycentric residual deviations of the pulse arrival times. The method is applied to observations of the pulsars PSR B1855+09 and PSR B1937+21, and is used to obtain corrections to UTC relative to the group pulsar time PT$_{\rm ens}$. Direct...
Source: http://arxiv.org/abs/1107.4263v2
Arxiv.org
by A. El Amili; V. Pal; F. Goldfarb; R. Ghosh; M. Alouini; I. Sagnes; F. Bretenaker
texts

eye 89

favorite 0

comment 0

We present an experimental observation of phase locking effects in the intensity noise spectrum of a semiconductor laser. These noise correlations are created in the medium by coherent carrier-population oscillations induced by the beatnote between the lasing and non-lasing modes of the laser. This phase locking leads to a modification of the intensity noise profile at around the cavity free-spectral-range value. The noise correlations are evidenced by varying the relative phase shift between...
Source: http://arxiv.org/abs/1107.5912v1
Arxiv.org
by A. Elmaslı; L. Fossati; C. P. Folsom; B. Albayrak; H. Izumiura
texts

eye 52

favorite 0

comment 0

The Ursa Major group is a nearby stellar supercluster which, while not gravitationally bound, is defined by co-moving members. DD UMa is a $\delta$ Scuti star whose membership in the Ursa Major group is unclear. The objective of this study is to confirm the membership of DD UMa in the Ursa Major group, as well as perform a detailed spectral analysis of the star. Since DD UMa is a low-amplitude $\delta$ Scuti star, we performed a frequency analysis. We determined fundamental parameters, chemical...
Source: http://arxiv.org/abs/1107.4856v1
Arxiv.org
by A. Endo; P. van der Werf; R. M. J. Janssen; P. J. de Visser; T. M. Klapwijk; J. J. A. Baselmans; L. Ferrari; A. M. Baryshev; S. J. C. Yates
texts

eye 61

favorite 0

comment 0

An integrated filterbank (IFB) in combination with microwave kinetic inductance detectors (MKIDs), both based on superconducting resonators, could be used to make broadband submillimeter imaging spectrographs that are compact and flexible. In order to investigate the possibility of adopting an IFB configuration for DESHIMA (Delft SRON High-redshift Mapper), we study the basic properties of a coplanar-waveguide-based IFB using electromagnetic simulation. We show that a coupling efficiency...
Source: http://arxiv.org/abs/1107.3333v1
Arxiv.org
texts

eye 85

favorite 0

comment 0

Stellar activity induces apparent radial velocity (RV) variations in late-type main-sequence stars that may hamper the detection of low-mass planets and the measurement of their mass. We use simultaneous measurements of the active planet host star HD189733 with high-precision optical photometry by the MOST satellite and high-resolution spectra by SOPHIE. We apply on this unique dataset a spot model to predict the activity-induced RV variations and compare them with the observed ones. The model...
Source: http://arxiv.org/abs/1107.4864v1
Arxiv.org
texts

eye 110

favorite 0

comment 0

The Parker model for coronal heating is investigated through a high resolution simulation. An inertial range is resolved where fluctuating magnetic energy E_M (k_perp) \propto k_\perp^{-2.7} exceeds kinetic energy E_K (k_\perp) \propto k_\perp^{-0.6}. Increments scale as \delta b_\ell \simeq \ell^{-0.85} and \delta u_\ell \simeq \ell^{+0.2} with velocity increasing at small scales, indicating that magnetic reconnection plays a prime role in this turbulent system. We show that spectral energy...
Source: http://arxiv.org/abs/1005.1640v2
Arxiv.org
by A. Fabricio Albuquerque; Nicolas Laflorencie; Jean-David Picon; Frédéric Mila
texts

eye 43

favorite 0

comment 0

We investigate the competition between spin-supersolidity and phase separation in a frustrated spin-half model of weakly coupled dimers. We start by considering systems of hard-core bosons on the square lattice, onto which the low-energy physics of the herein investigated spin model can be mapped, and devise a criterion for gauging the interplay between supersolid order and domain wall formation based on strong coupling arguments. Effective bosonic models for the spin model are derived via the...
Source: http://arxiv.org/abs/1005.0638v3
Arxiv.org
by A. Felner; S. Hanan; R. E. Korf
texts

eye 72

favorite 0

comment 0

We explore a method for computing admissible heuristic evaluation functions for search problems. It utilizes pattern databases, which are precomputed tables of the exact cost of solving various subproblems of an existing problem. Unlike standard pattern database heuristics, however, we partition our problems into disjoint subproblems, so that the costs of solving the different subproblems can be added together without overestimating the cost of solving the original problem. Previously, we...
Source: http://arxiv.org/abs/1107.0050v1
Arxiv.org
texts

eye 109

favorite 0

comment 0

Detectors at a high-energy muon collider must be protected from the decay products of beam muons by installing shielding material around the beam pipe. In this article, the impact of these blind detector regions on new-physics signatures with invisible final-state particles is shown by studying the production of sleptons, the superpartners of leptons. Special attention is given to large backgrounds from two-photon collisions. It is demonstrated how the influence of these backgrounds can be...
Source: http://arxiv.org/abs/1107.3853v1
Arxiv.org
texts

eye 67

favorite 0

comment 0

The common lore in the literature of neutrino mass generation is that the canonical see-saw mechanism beautifully offers an explanation for the tiny neutrino mass but at the cost of introducing right-handed neutrinos at a scale that is out of range for the current experiments. The inverse see-saw mechanism is an interesting alternative to the canonical one once it leads to tiny neutrino masses with the advantage of being testable at TeV scale. However, this last mechanism suffers from an issue...
Source: http://arxiv.org/abs/1107.0739v3
Arxiv.org
by A. G. Kuhn; M. Bahriz; O. Ducloux; C. Chartier; O. Le Traon; T. Briant; P. -F. Cohadon; A. Heidmann; C. Michel; L. Pinard; R. Flaminio
texts

eye 112

favorite 0

comment 0

We present a new micromechanical resonator designed for cavity optomechanics. We have used a micropillar geometry to obtain a high-frequency mechanical resonance with a low effective mass and a very high quality factor. We have coated a 60-$\mu$m diameter low-loss dielectric mirror on top of the pillar and are planning to use this micromirror as part of a high-finesse Fabry-Perot cavity, to laser cool the resonator down to its quantum ground state and to monitor its quantum position...
Source: http://arxiv.org/abs/1107.3828v1
Arxiv.org
by A. Gerschenfeld; B. Derrida
texts

eye 104

favorite 0

comment 0

The ABC model is a simple diffusive one-dimensional non-equilibrium system which exhibits a phase transition. Here we show that the cumulants of the currents of particles through the system become singular near the phase transition. At the transition, they exhibit an anomalous dependence on the system size (an anomalous Fourier's law). An effective theory for the dynamics of the single mode which becomes unstable at the transition allows one to predict this anomalous scaling.
Source: http://arxiv.org/abs/1107.2323v1
Arxiv.org
by A. Goasduff; S. Courtin; F. Haas; D. Lebhertz; D. G. Jenkins; C. Beck; J. Fallis; C. Ruiz; D. A. Hutcheon; P. -A. Amandruz; C. Davis; U. Hager; D. Ottewell; G. Ruprecht
texts

eye 84

favorite 0

comment 0

We have performed a heavy ion radiative capture reaction between two light heavy ions, $^{12}$C and $^{16}$O, leading to $^{28}$Si. The present experiment has been performed below Coulomb barrier energies in order to reduce the phase space and to try to shed light on structural effects. Obtained $\gamma$-spectra display a previously unobserved strong feeding of intermediate states around 11 MeV at these energies. This new decay branch is not fully reproduced by statistical nor semi-statistical...
Source: http://arxiv.org/abs/1107.1124v1
Arxiv.org
by A. Gonzalez-Tudela; D. Martin-Cano; E. Moreno; L. Martin-Moreno; F. J. Garcia-Vidal; C. Tejedor
texts

eye 145

favorite 0

comment 0

We exploit the qubit-qubit coupling induced by plasmon-polariton modes in a one-dimensional nanowaveguide to obtain various two-qubit entanglement situations. Firstly, we observe three phenomena occurring when preparing the initial state of the system and leaving it freely relax: spontaneous formation of entanglement, sudden birth and revival. Then, we show that plugging a laser to each of the qubit, the system arrives to an steady state which, depending on their inter-qubit distance, can also...
Source: http://arxiv.org/abs/1107.0584v2
Arxiv.org
by A. Gordillo-Guerrero; R. Kenna; J. J. Ruiz-Lorenzo
texts

eye 48

favorite 0

comment 0

We use a high-precision Monte Carlo simulation to determine the universal specific-heat amplitude ratio A+/A- in the three-dimensional Ising model via the impact angle \phi of complex temperature zeros. We also measure the correlation-length critical exponent \nu from finite-size scaling, and the specific-heat exponent \alpha through hyperscaling. Extrapolations to the thermodynamic limit yield \phi = 59.2(1.0) degrees, A+/A- = 0.56(3), \nu = 0.63048(32) and \alpha = 0.1086(10). These results...
Source: http://arxiv.org/abs/1107.1186v3
Arxiv.org
by A. Gutierrez-Rodriguez; Javier Peressutti; O. A. Sampayo
texts

eye 93

favorite 0

comment 0

We analyzed the double production and the triple self-coupling of the standard model Higgs boson at future $\gamma \gamma$ collider energies, with the reactions $\gamma\gamma \rightarrow f \bar f HH$ $(f=b, t)$. We evaluated the total cross section for $f\bar fHH$ and calculated the total number of events considering the complete set of Feynman diagrams at tree-level and for different values of the triple coupling $\kappa\lambda_{HHH}$. We have also analyzed the sensitivity for the considered...
Source: http://arxiv.org/abs/1107.0245v1
Arxiv.org
by A. Gynther; K. Landsteiner; F. Pena-Benitez; A. Rebhan
texts

eye 28

favorite 0

comment 0

We calculate anomaly induced conductivities from a holographic gauge theory model using Kubo formulas, making a clear conceptual distinction between thermodynamic state variables such as chemical potentials and external background fields. This allows us to pinpoint ambiguities in previous holographic calculations of the chiral magnetic conductivity. We also calculate the corresponding anomalous current three-point functions in special kinematic regimes. We compare the holographic results to...
Source: http://arxiv.org/abs/1005.2587v2
Arxiv.org
texts

eye 112

favorite 0

comment 0

We consider the "Method of particular solutions" for numerically computing eigenvalues and eigenfunctions of the Laplacian $\Delta$ on a smooth, bounded domain Omega in RR^n with either Dirichlet or Neumann boundary conditions. This method constructs approximate eigenvalues E, and approximate eigenfunctions u that satisfy $\Delta u=Eu$ in Omega, but not the exact boundary condition. An inclusion bound is then an estimate on the distance of E from the actual spectrum of the Laplacian,...
Source: http://arxiv.org/abs/1107.2172v1
Arxiv.org
by A. H. W. Kuepper; Th. Maschberger; P. Kroupa; H. Baumgardt
texts

eye 34

favorite 0

comment 0

By analysing models of the young massive cluster R136 in 30 Doradus, set-up using the herewith introduced and publicly made available code McLuster, we investigate and compare different methods for detecting and quantifying mass segregation and substructure in non-seeing limited N-body data. For this purpose we generate star cluster models with different degrees of mass segregation and fractal substructure and analyse them. We quantify mass segregation by measuring, from the projected 2d model...
Source: http://arxiv.org/abs/1107.2395v2
Arxiv.org
texts

eye 141

favorite 0

comment 0

Context. Low-mass star-forming cores differ from their surrounding molecular cloud in turbulence, shape, and density structure. Aims. We aim to understand how dense cores form out of the less dense cloud material by studying the connection between these two regimes. Methods. We observed the L1517 dark cloud in C18O(1-0), N2H+(1-0), and SO(JN=32-21) with the FCRAO 14m telescope, and in the 1.2mm dust continuum with the IRAM 30m telescope. Results. Most of the gas in the cloud lies in four...
Source: http://arxiv.org/abs/1107.0971v2
Arxiv.org
by A. Herzog; P. Horsch; A. M. Oles; J. Sirker
texts

eye 41

favorite 0

comment 0

Ferromagnetic, in contrast to antiferromagnetic, Heisenberg chains can undergo a Spin-Peierls dimerization only at finite temperatures. They show reentrant behavior as a function of temperature, which might play a role for systems with small effective elastic constants as, for example, monatomic chains on surfaces. We investigate the physical properties of the dimerized ferromagnetic Heisenberg chain using a modified spin-wave theory. We calculate the exponentially decaying spin and dimer...
Source: http://arxiv.org/abs/1107.2772v1
Arxiv.org
by A. Hietanen; B. Lucini
texts

eye 72

favorite 0

comment 0

We propose a general method (based on the Wang-Landau algorithm) to compute numerically free energies that are obtained from the logarithm of the ratio of suitable partition functions. As an application, we determine with high accuracy the order-order interface tension of the four-state Potts model in three dimensions on cubic lattices of linear extension up to L=56. The infinite volume interface tension is then extracted at each beta from a fit of the finite volume interface tension to a known...
Source: http://arxiv.org/abs/1107.1637v2
Arxiv.org
by A. Humphrey; M. Zeballos; I. Aretxaga; D. H. Hughes; M. S. Yun; R. Cybulski; Grant W. Wilson; J. Austermann; H. Ezawa; R. Kawabe; K. Kohno; T. Perera; K. Scott; D. Sánchez-Arguelles; R. Gutermuth
texts

eye 49

favorite 0

comment 0

We present 1.1 mm observations for a sample of 16 powerful radio galaxies at 0.5
Source: http://arxiv.org/abs/1107.3120v1
Arxiv.org
by A. I. Agafonov; E. A. Manykin
texts

eye 81

favorite 0

comment 0

We point out that the free single-fermion propagator which is used in the QFT equations for two-fermion systems, has a bosonic structure, transforms to the single-boson propagator for the Klein-Gordon equation in the nonrelativistic limit, and, therefore, does not satisfy the Lehmann spectral representation for fermions. Proceeding from the Lippmann-Schwinger integral equation, we obtain a two-fermion relativistic wave equation in which the free two-fermion equal-time propagator satisfying the...
Source: http://arxiv.org/abs/math-ph/9906016v2
Arxiv.org
texts

eye 83

favorite 0

comment 0

The critical indices alpha', beta, gamma' and delta of the Quark Gluon Bags with Surface Tension Model with the tricritical and critical endpoint are calculated as functions of the usual parameters of this model and two newly introduced parameters (indices). The critical indices are compared with that ones of other models. The universality class of the present model with respect to values of the model parameters is discussed. The scaling relations for the found critical exponents are verified...
Source: http://arxiv.org/abs/1107.1423v1
Arxiv.org
by A. I. Molev
texts

eye 53

favorite 0

comment 0

We show that the Pfaffian of a generator matrix for the affine Kac--Moody algebra hat o_{2n} is a Segal--Sugawara vector. Together with our earlier construction involving the symmetrizer in the Brauer algebra, this gives a complete set of Segal--Sugawara vectors in type D.
Source: http://arxiv.org/abs/1107.5417v1
We {characterize the multipartite entanglement in a quantum system by the quantity} which vanishes if only the quantum system may be decomposed into two weakly entangled subsystems, unlike measures of multipartite entanglement introduced before. We refer to this {quantity} as the minimal entanglement of bipartite decompositions (MEBD). Big MEBD means that the system may not be decomposed into two weakly entangled subsystems. MEBD allows one to define, for instance, whether the given quantum...
Source: http://arxiv.org/abs/1005.5531v2
We introduce a measure of quantum correlations in the $N$-qubit quantum system which is invariant with respect to the $SU(2^N)$ group of transformations of this system. This measure is a modification of the quantum discord introduced earlier and is referred to as the unitary or $SU(2^N)$-invariant discord. Since the evolution of a quantum system is equivalent to the proper unitary transformation, the introduced measure is an integral of motion and is completely defined by eigenvalues of the...
Source: http://arxiv.org/abs/1107.4743v3
Arxiv.org
texts

eye 97

favorite 0

comment 0

We present a detailed discussion of the solution of Nambu-Gor'kov equations in superfluid nuclei, which provide a consistent framework to deal with the interplay between particle-hole and particle- particle channel, including the effects of the fragmentation of the quasiparticle strength and of the pairing interaction induced by the exchange of collective vibrations. The coupling between quasiparticle and vibrations is determined from the experimental polarizability of the low-lying collective...
Source: http://arxiv.org/abs/1107.0251v1
Arxiv.org
texts

eye 87

favorite 0

comment 0

Analytical calculations of phase transitions in AdS3 Maxwell-scalar system, modeling a holographic superconductor, are performed in the probe limit of BTZ black hole background. Estimated values of the phase transition critical temperature and of the scalar boundary operator are compared with that obtained in numerical simulations. We discuss extensions of the model to topologically massive QED3 and to inclusion of external magnetic field. The latter becomes possible through the Barnett-London...
Source: http://arxiv.org/abs/1107.2909v1
Arxiv.org
by A. J. Penner; N. Andersson; L. Samuelsson; I. Hawke; D. I. Jones
texts

eye 103

favorite 0

comment 0

We discuss the response of neutron stars to the tidal interaction in a compact binary system, as encoded in the Love number associated with the induced deformation. This problem is of interest for gravitational-wave astronomy as there may be a detectable imprint on the signal from the late stages of binary coalescence. Previous work has focussed on simple barotropic neutron star models, providing an understanding of the role of the stellar compactness and overall density profile. We add realism...
Source: http://arxiv.org/abs/1107.0669v1
Arxiv.org
by A. J. W. Hilton; E. R. Vaughan
texts

eye 85

favorite 0

comment 0

Hall's Condition is a necessary condition for a partial latin square to be completable. Hilton and Johnson showed that for a partial latin square whose filled cells form a rectangle, Hall's Condition is equivalent to Ryser's Condition, which is a necessary and sufficient condition for completability. We give what could be regarded as an extension of Ryser's Theorem, by showing that for a partial latin square whose filled cells form a rectangle, where there is at most one empty cell in each...
Source: http://arxiv.org/abs/1107.2639v1
Arxiv.org
by A. Jain; L. Louahadj; J. Peiro; J. C. Le Breton; C. Vergnaud; A. Barski; C. Beigné; L. Notin; A. Marty; V. Baltz; S. Auffret; E. Augendre; H. Jaffrès; J. M. George; M. Jamet
texts

eye 172

favorite 0

comment 0

In this letter, we report on successful electrical spin injection and detection in \textit{n}-type germanium-on-insulator (GOI) using a Co/Py/Al$_{2}$O$_{3}$ spin injector and 3-terminal non-local measurements. We observe an enhanced spin accumulation signal of the order of 1 meV consistent with the sequential tunneling process via interface states in the vicinity of the Al$_{2}$O$_{3}$/Ge interface. This spin signal is further observable up to 220 K. Moreover, the presence of a strong...
Source: http://arxiv.org/abs/1107.3510v1
Arxiv.org
by A. Johansen; I. Simonsen
texts

eye 122

favorite 0

comment 0

It is demonstrated that the US economy has on the long-term in reality been governed by the Keynesian approach to economics independent of the current official economical policy. This is done by calculating the two-point correlation function between the fluctuations of the DJIA and the US public debt. We find that the origin of this condition is mainly related to the wars that the USA has fought during the time period investigated. Wars mean a large influx of public money into the economy, thus...
Source: http://arxiv.org/abs/1107.3095v1
Arxiv.org
texts

eye 82

favorite 0

comment 0

In this work, the PLECHDE model with Granda-Oliveros (G-O) IR-cutoff is studied. The evolution of dark energy density, deceleration and EoS parameters are calculated. I demonstrate that under a condition, our universe can accelerate near the phantom barrier at present time. We calculate these parameters also in PLECHDE at Ricci scale, when when $\alpha=2$ and $\beta=1$, and at last a comparison between Ricci scale, G-O cutoff and non-corrected HDE without matter field with G-O cutoff is done....
Source: http://arxiv.org/abs/1107.5455v2
Arxiv.org
by A. Kobayashi; Y. Suzumura; F. Piéchon; G. Montambaux
texts

eye 71

favorite 0

comment 0

We re-examine the band structure of the stripe charge ordered state of $\alpha$-(BEDT-TTF)$_2$I$_3$ under pressure by using an extended Hubbard model within the Hartree mean-field theory. By increasing pressure, we find a topological transition from a conventional insulator with a single-minimum in the dispersion relation at the M-point in the Brillouin zone, towards a new phase which exhibits a double-minimum. This transition is characterized by the appearance of a pair of Dirac electrons with...
Source: http://arxiv.org/abs/1107.4841v1
Arxiv.org
by A. Kotzinian; M. Anselmino; V. Barone
texts

eye 57

favorite 0

comment 0

We shortly describe the leading twist formalism of spin and transverse-momentum dependent fracture functions recently developed and present results for the production of spinless hadrons in the target fragmentation region (TFR) of SIDIS. In this case not all fracture functions can be accessed and only a Sivers-like single spin azimuthal asymmetry shows up at LO cross-section. Then, we demonstrate that the measurement of spin dependent azimuthal asymmetries in double hadron production in...
Source: http://arxiv.org/abs/1107.2292v1
Arxiv.org
by A. Kumar; N. Samkharadze; M. J. Manfra; G. A. Csathy; L. N. Pfeiffer; K. W. West
texts

eye 78

favorite 0

comment 0

We report the first unambiguous observation of a fractional quantum Hall state in the Landau level of a two-dimensional hole sample at the filling factor $\nu=8/3$. We identified this state by a quantized Hall resistance and an activated temperature dependence of the longitudinal resistance and found an energy gap of 40 mK. To our surprise the particle-hole conjugate state at filling factor $\nu=7/3$ in our sample does not develop down to 6.9 mK. This observation is contrary to that in electron...
Source: http://arxiv.org/abs/1007.1504v2
Arxiv.org
by A. L. Marchant; S. Haendel; T. P. Wiles; S. A. Hopkins; C. S. Adams; S. L. Cornish
texts

eye 210

favorite 0

comment 0

We present a simple technique for stabilization of a laser frequency off resonance using the Faraday effect in a heated vapor cell with an applied magnetic field. In particular we demonstrate stabilization of a 780 nm laser detuned up to 14 GHz from the 85Rb D2 5 2S_1/2 F = 2 to 5 2P_3/2 F' = 3 transition. Control of the temperature of the vapor cell and the magnitude of the applied magnetic field allows locking ~6-14 GHz red and blue detuned from the atomic line. We obtain an rms fluctuation...
Source: http://arxiv.org/abs/1007.2531v2
Treating a realistic problem in any field of reaction kinetics raises a series of problems: we review these illustrated with examples using ReactionKinetics, a Mathematica based package.
Source: http://arxiv.org/abs/1107.3098v1