April 2009 arXiv papers — page 2

Andrzej J. Buras

We summarize briefly the CKM picture of flavour and CP violation that governs the models with minimal flavour violation (MFV). We then describe how this framework can be efficiently tested through particle-antiparticle mixing and rare $K$ and B decays. In particular we provide a list of theoretically clean tests that the simplest version of the MFV framework

S. Ramelow, L. Ratschbacher, A. Fedrizzi, N. K. Langford

Although frequency multiplexing of information has revolutionized the field of classical communications, the color degree of freedom (DOF) has been used relatively little for quantum applications. We experimentally demonstrate a new hybrid quantum gate that transfers polarization entanglement of non-degenerate photons onto the color DOF. We create, for the f

B. Hunt, E. Pratt, V. Gadagkar, M. Yamashita

Although solid helium-4 (4He) may be a supersolid it also exhibits many phenomena unexpected in that context. We studied relaxation dynamics in the resonance frequency f(T) and dissipation D(T) of a torsional oscillator containing solid 4He. With the appearance of the "supersolid" state, the relaxation times within f(T) and D(T) began to increase rap

Harry J. Lipkin

Final states produced by a decay have a much broader energy spectrum than the natural line width at times much shorter than the decay lifetime. This tends to render impossible the use for neutrino detection of the high value of the resonance absorption cross section at the peak of the resonance.

Xiaoli Tang, Tong Lin, Steve Jiang

We propose a novel approach for potential on-line treatment verification using cine EPID (Electronic Portal Imaging Device) images for hypofractionated lung radiotherapy based on a machine learning algorithm. Hypofractionated radiotherapy requires high precision. It is essential to effectively monitor the target to ensure that the tumor is within the beam ap

Michael T. Goodrich

In this paper, we study the algorithmic complexity of the Mastermind game, where results are single-color black pegs. This differs from the usual dual-color version of the game, but better corresponds to applications in genetics. We show that it is NP-complete to determine if a sequence of single-color Mastermind results have a satisfying vector. We also sho

M. Gharbi, Z. H. Sun, P. Sharma, K. White

Metals exhibit a size-dependent hardening when subject to indentation. Mechanisms for this phenomenon have been intensely researched in recent times. Does such a size-effect also exist in the electromechanical behavior of ferroelectrics?--if yes, what are the operative mechanisms? Our experiments on BaTiO3 indeed suggest an electromechanical size-effect. We

Chandreyee Sengupta, K. S. Dwarakanath, D. J. Saikia

We present the results of Giant Metrewave Radio Telescope (GMRT) observations of the interacting system Arp86 in both neutral atomic hydrogen, HI, and in radio continuum at 240, 606 and 1394 MHz. In addition to HI emission from the two dominant galaxies, NGC7752 and NGC7753, these observations show a complex distribution of HI tails and bridges due to tidal

Konstantin V. Getman, Eric D. Feigelson, Kevin L. Luhman, Aurora Sicilia-Aguilar

The Cepheus B (CepB) molecular cloud and a portion of the nearby CepOB3b OB association, one of the most active regions of star formation within 1 kpc, have been observed with the IRAC detector on board the Spitzer Space Telescope. The goals are to study protoplanetary disk evolution and processes of sequential triggered star formation in the region. Out of

P. Kalmus, K. C. Cannon, S. Marka, B. J. Owen

Soft gamma repeaters (SGRs) have unique properties that make them intriguing targets for gravitational wave (GW) searches. They are nearby, their burst emission mechanism may involve neutron star crust fractures and excitation of quasi-normal modes, and they burst repeatedly and sometimes spectacularly. A recent LIGO search for transient GW from these source

Johannes Walcher

We study normal functions capturing D-brane superpotentials on several one- and two-parameter Calabi-Yau hypersurfaces and complete intersections in weighted projective space. We calculate in the B-model and interpret the results using mirror symmetry in the large volume regime, albeit without identifying the precise A-model geometry in all cases. We identif

K. A. Bronnikov, O. B. Zaslavskii

For arbitrary static space-times, it is shown that an equilibrium between a Killing horizon and matter is only possible for some discrete values of the parameter $w = p_1/ρ$, where $ρ$ is the density and $p_1$ is pressure in the direction normal to the horizon. In the generic situation of a simple (non-extremal) horizon and the slowest possible density decre

Miquel Payaró, Daniel P. Palomar

The design of the precoder the maximizes the mutual information in linear vector Gaussian channels with an arbitrary input distribution is studied. Precisely, the precoder optimal left singular vectors and singular values are derived. The characterization of the right singular vectors is left, in general, as an open problem whose computational complexity is

J. M. Densmore, P. Das, K. Rovira, T. D. Blasius

We present studies of the magnetic field distribution around the vortices in LuNi2B2C. Small-angle neutron scattering measurements of the vortex lattice (VL) in this material were extended to unprecedentedly large values of the scattering vector q, obtained both by using high magnetic fields to decrease the VL spacing and by using higher order reflections. A

E. Bogomolny, O. Giraud, C. Schmit

A method to generate new classes of random matrix ensembles is proposed. Random matrices from these ensembles are Lax matrices of classically integrable systems with a certain distribution of momenta and coordinates. The existence of an integrable structure permits to calculate the joint distribution of eigenvalues for these matrices analytically. Spectral s

A Marshall Stoneham, A H Harker, Gavin W Morley

We assess routes to a diamond-based quantum computer, where we specifically look towards scalable devices, with at least 10 linked quantum gates. Such a computer should satisfy the deVincenzo rules and might be used at convenient temperatures. The specific examples we examine are based on the optical control of electron spins. For some such devices, nuclear

J. Martin Camalich, L. Alvarez-Ruso, L. S. Geng, M. J. Vicente Vacas

We report a calculation of the baryon magnetic moments using covariant chiral perturbation theory within the extended-on-mass-shell renormalization scheme including intermediate octet and decuplet contributions. By fitting the two available low-energy constants, we improve the Coleman-Glashow description of the data when we include the leading SU(3) breaking

Elena F. Sheka

The reactions of fullerene C60 with atomic fluorine have been studied by unrestricted broken spin-symmetry Hartree-Fock (UBS HF) approach implemented in semiempirical codes based on AM1 technique. The calculations were focused on a sequential addition of fluorine atom to the fullerene cage following indication of the cage atom highest chemical susceptibility

G. L. Klimchitskaya, E. V. Blagov, V. M. Mostepanenko

Problems in the Lifshitz theory of atom-wall interaction arise when the dc conductivity of dielectric wall is included into the model of the dielectric response. We review the low-temperature behavior of the free energy and entropy of dispersion interaction for both dielectric and metallic walls. Consistency of the obtained results with thermodynamics and ex

A. N. Chantis, R. C. Albers, A. Svane, N. E. Christensen

We present results for the electronic structure of plutonium by using a recently developed quasiparticle self-consistent $GW$ method (\qsgw). We consider a paramagnetic solution without spin-orbit interaction as a function of volume for the face-centered cubic (fcc) unit cell. We span unit-cell volumes ranging from 10% greater than the equilibrium volume of

Veronica M. Sanchez, Mariela Sued, Damian A. Scherlis

Continuum solvent models have become a standard technique in the context of electronic structure calculations, yet, no implementations have been reported capable to perform molecular dynamics at solid-liquid interfaces. We propose here such a continuum approach in a DFT framework, using plane-waves basis sets and periodic boundary conditions. Our work stems

Dmitry Bolotov

In this note we construct a closed 4-manifold having torsion-free fundamental group and whose universal covering is of macroscopic dimension 3. This yields a counterexample to Gromov's conjecture about the falling of macroscopic dimension.

Korinna Zapp, Johanna Stachel, Urs Achim Wiedemann

The Monte Carlo model JEWEL 1.0 (Jet Evolution With Energy Loss) simulates parton shower evolution in the presence of a dense QCD medium. In its current form medium interactions are modelled as elastic scattering based on perturbative matrix elements and a simple prescription for medium induced gluon radiation. The parton shower is interfaced with a hadronis

Hiroshi Itoyama, Reiji Yoshioka

Effects of matrix orientifolding that preserves supersymmetries are considered in the IIB matrix model with regard to its effective dynamics generated for diagonal elements. Taking the case of maximal supersymmetries and the long distance expansion of the one-loop effective action as well as cases where the size of the matrices is small, we demonstrate that

A. Lyashenko, A. Breskin, R. Chechik, T. H. V. T. Dias

The operation of visible-sensitive gaseous- and, to some extent, vacuum-photomultipliers is critically affected by secondary electrons originating from ion impact on the photocathode. A simple method for indirect measurement of the effective ion-induced secondary-electron emission (IISEE) coefficient from the photocathode into a gas medium, $γ_+^{eff}$ was d

Sandro Mereghetti

Several observations obtained in the last few years indicate that Soft Gamma-ray Repeaters (SGRs) and Anomalous X-ray Pulsars (AXPs) are basically a single class of isolated neutron stars. Their properties are well explained by the magnetar model, based on neutron stars powered by magnetic fields as high as 10^14 -10^15 G. Here I report some recent results o

Alan Coley, Sigbjorn Hervik, Nicos Pelavas

In this paper we investigate four dimensional Lorentzian spacetimes with constant curvature invariants ($CSI$ spacetimes). We prove that if a four dimensional spacetime is $CSI$, then either the spacetime is locally homogeneous or the spacetime is a Kundt spacetime for which there exists a frame such that the positive boost weight components of all curvature

C. Kuckein, R. Centeno, V. Martinez Pillet, R. Casini

We study the vector magnetic field of a filament observed over a compact Active Region Neutral Line. Spectropolarimetric data acquired with TIP-II (VTT, Tenerife, Spain) of the 10830 Åspectral region provide full Stokes vectors which were analyzed using three different methods: magnetograph analysis, Milne-Eddington inversions and PCA-based atomic polarizati

Pedro Ruiz-Femenia

The dominant contribution of the next-to-leading order perturbative QCD corrections to the Upsilon -> X gamma photon energy spectrum for photon energies w ~ m_b alpha_s can be obtained trivially from the knowledge of the corresponding O(alpha) correction to the positronium decay spectrum in the same region. The latter can be obtained from the NRQED computati

Mario A. T. Figueiredo, Jose M. Bioucas-Dias, Manya V. Afonso

We propose a new fast algorithm for solving one of the standard formulations of frame-based image deconvolution: an unconstrained optimization problem, involving an $\ell_2$ data-fidelity term and a non-smooth regularizer. Our approach is based on using variable splitting to obtain an equivalent constrained optimization formulation, which is then addressed w

L. Czekaj, J. K. Korbicz, R. W. Chhajlany, P. Horodecki

We study classical capacity regions of quantum Gaussian multiple access channels (MAC). In classical variants of such channels, whilst some capacity superadditivity-type effects such as the so called {\it water filling effect} may be achieved, a fundamental classical additivity law can still be identified, {\it viz.} adding resources to one sender is never a

Mario A. T. Figueiredo, Jose M. Bioucas-Dias

Although much research has been devoted to the problem of restoring Poissonian images, namely in the fields of medical and astronomical imaging, applying the state of the art regularizers (such as those based on wavelets or total variation) to this class of images is still an open research front. This paper proposes a new image deconvolution approach for ima

M. Mocak, E. Mueller, A. Weiss, K. Kifonidis

We describe and discuss hydrodynamic simulations of the core helium flash using an initial model of a 1.25 M_sol star with a metallicity of 0.02 near at its peak. Past research concerned with the dynamics of the core helium flash is inconclusive. Its results range from a confirmation of the standard picture, where the star remains in hydrostatic equilibrium

A. S. Alexandrov, I. O. Thomas

Kinetic energy driven phase transitions in Bose superfluids occur at low values of the repulsion when the values of the next-to-nearest and next-to-next-to-nearest hopping term attain certain critical values, resulting in alterations in the wave vector of the condensate. We map out the space of possible phases allowed by particular forms of the single-partic

Giuseppe Bimonte, Enrico Calloni, Giampiero Esposito, George M. Napolitano

We review and assess a part of the recent work on Casimir apparatuses in the weak gravitational field of the Earth. For a free, real massless scalar field subject to Dirichlet or Neumann boundary conditions on the parallel plates, the resulting regularized and renormalized energy-momentum tensor is covariantly conserved, while the trace anomaly vanishes if t

A. Pouquet, J. Baerenzung, J. Pietarila Graham, P. Mininni

We present two models for turbulent flows with periodic boundary conditions and with either rotation, or a magnetic field in the magnetohydrodynamics (MHD) limit. One model, based on Lagrangian averaging, can be viewed as an invariant-preserving filter, whereas the other model, based on spectral closures, generalizes the concepts of eddy viscosity and eddy n

G. Handler

We carried out a multi-colour time-series photometric study of six stars claimed as "hybrid" p and g mode pulsators in the literature. Gamma Peg was confirmed to show short-period oscillations of the Beta Cep type and simultaneous long-period pulsations typical of Slowly Pulsating B (SPB) stars. From the measured amplitude ratios in the Stromgren uvy

Saeed Nasseh, Massoud Tousi

Avramov and Buchweitz proved that for finitely generated modules $M$ and $N$ over a complete intersection local ring $R$, $\Ext^i_R(M,N)=0$ for all $i\gg 0$ implies $\Ext^i_R(N,M)=0$ for all $i\gg 0$. In this note we give some generalizations of this result. Indeed we prove the above mentioned result when (1) $M$ is finitely generated and $N$ is arbitrary, (

P. Osland, A. A. Pankov, N. Paver, A. V. Tsytrinov

Heavy resonances appearing in the clean Drell-Yan channel may be the first new physics to be observed at the proton-proton CERN LHC. If a new resonance is discovered at the LHC as a peak in the dilepton invariant mass distribution, the characterization of its spin and couplings will proceed via measuring production rates and angular distributions of the deca

N. Didier, A. Minguzzi, F. W. J. Hekking

We develop a generalized harmonic-fluid approach, based on a regularization of the effective low-energy Luttinger-liquid Hamiltonian, for a one-dimensional Bose gas with repulsive contact interactions. The method enables us to compute the complete series corresponding to the large-distance, off-diagonal behavior of the one-body density matrix for any value o

S. Bauch, M. Bonitz

Electrons colliding with spatially fixed ions in strong laser fields are investigated by solving the time-dependent Schrödinger equation. Considering first simple one-dimensional model systems, the mechanisms and energy spectra of fast electrons are analyzed, starting from collisions on a single ion. By using these electrons as projectiles for a second and t

Douglas C. Heggie, Mirek Giersz

M4 and NGC 6397 are two very similar galactic globular clusters, which differ mainly in their surface brightness profile. M4 has a classic King-like profile, whereas NGC 6397 has a more concentrated profile, which is often interpreted as that of a post-core collapse cluster. Heggie & Giersz (2008), however, found that M4 is also a post-core collapse cluster,

Nikolaos Fountoulakis, Anna Huber, Konstantinos Panagiotou

Broadcasting algorithms are of fundamental importance for distributed systems engineering. In this paper we revisit the classical and well-studied push protocol for message broadcasting. Assuming that initially only one node has some piece of information, at each stage every one of the informed nodes chooses randomly and independently one of its neighbors an

Jorge Kurchan, Dov Levine

Crystals and quasicrystals can be characterized by an order that is a purely geometric property of an instantaneous configuration, independent of particle dynamics or interactions. Glasses, on the other hand, are ostensibly amorphous arrangements of particles. A natural and long-standing question has been whether they too have, albeit in a hidden way, some f

D. C. Hannikainen, R. W. Hunstead, K. Wu, V. McIntyre

We revisit the discovery outburst of the X-ray transient XTE J1550-564 during which relativistic jets were observed in 1998 September, and review the radio images obtained with the Australian Long Baseline Array, and lightcurves obtained with the Molonglo Observatory Synthesis Telescope and the Australia Telescope Compact Array. Based on HI spectra, we const

A. Gonzalez-Tudela, E. del Valle, C. Tejedor, F. P. Laussy

We compare the observed splitting in the PL spectrum of a strongly coupled light-matter system, with the splitting of its dressed modes. In the presence of non-negligible decoherence, the two may differ considerably. Whereas the dressed mode splitting has a simple expression, the observed splitting has no general analytical expression in terms of radicals of

Decio Levi, Christian Scimiterna

In this article we show that the complex Burgers and the Kundu--Eckhaus equations are related by a Miura transformation. We use this relation to discretize the Kundu--Eckhaus equation.

Gunnar Boldhaus, Konstantin Klemm

The functioning of a living cell is largely determined by the structure of its regulatory network, comprising non-linear interactions between regulatory genes. An important factor for the stability and evolvability of such regulatory systems is neutrality - typically a large number of alternative network structures give rise to the necessary dynamics. Here w

Lee Smolin

A quantization of unimodular gravity is described, which results in a quantum effective action which is also unimodular, ie a function of a metric with fixed determinant. A consequence is that contributions to the energy momentum tensor of the form of the metric times a spacetime constant, whether classical or quantum, are not sources of curvature in the equ

Richard Lieu, T. W. B. Kibble

We suggest here a mechanism for the seeding of the primordial density fluctuations. We point out that a process like reheating at the end of inflation will inevitably generate perturbations, even on superhorizon scales, by the local diffusion of energy. Provided that the reheating temperature is of order the GUT scale, the density contrast $δ_R$ for spheres

Klaus Lange

Two constructed prime number subsets (called prime brother & sisters and prime cousins) lead to a third one (called isolated primes) so that all three disjoint subsets together generate the prime number set. It should be suggested how the subset of isolated primes give a new approach to expand the set theory by using virtual subsets.

Pierre-Emmanuel Chaput, Nicolas Perrin

This paper gathers results obtained with a software written in Java. For exceptional minuscule, quasi-minuscule, cominuscule or adjoint homogeneous spaces, the Schubert cells are expressed as polynomials in the generators of the quantum cohomology algebra.

Nikolaos Mavridis, Shervin Emami, Chandan Datta, Wajahat Kamzi

Our project aims at supporting the creation of sustainable and meaningful longer-term human-robot relationships through the creation of embodied robots with face recognition and natural language dialogue capabilities, which exploit and publish social information available on the web (Facebook). Our main underlying experimental hypothesis is that such relatio

Petr Seba

During the attempt to line up into a dense traffic people have necessarily to share a limited space under turbulent conditions. From the statistical point view it generally leads to a probability distribution of the distances between the traffic objects (cars or pedestrians). But the problem is not restricted on humans. It comes up again when we try to descr

Daniel Heißelmann, Jürgen Blum, Kristin Wolling

In this work, we report on microgravity studies of particle ensembles simulating ice-particle collisions in Saturn's dense main rings. We have developed an experimental method to study the energy dissipation in a many-body system consisting of approx. one hundred cm-sized glass spheres. The temporal development of the mean particle velocity, ranging from

N. G. Parker, M. J. W. Povey

Acoustics provides a powerful modality with which to 'see' the mechanical properties of a wide range of elastic materials. It is particularly adept at probing soft materials where excellent contrast and propagation distance can be achieved. We have constructed a scanning acoustic microscope capable of mapping the microstructure of such materials. We

J. R. Persson

A new method for determining the hyperfine anomaly, without knowing the nuclear magnetic moment, is used for the first time on a series of unstable isotopes. The relative large number of experimental data in Eu makes it possible to determine the hyperfine anomaly for a number of unstable isotopes. Calculations of the Bohr-Weisskopf effect and hence the hyper

Zhi-Qiang Jiang, Fei Ren, Gao-Feng Gu, Qun-Zhao Tan

Massive multiplayer online role-playing games (MMORPGs) are very popular in past few years. The profit of an MMORPG company is proportional to how many users registered, and the instant number of online avatars is a key factor to assess how popular an MMORPG is. We use the on-off-line logs on an MMORPG server to reconstruct the instant number of online avata

J. Cáceres, C. Hernando, M. Mora, M. L. Puertas

A set of vertices $S$ \emph{resolves} a graph $G$ if every vertex is uniquely determined by its vector of distances to the vertices in $S$. The \emph{metric dimension} of a graph $G$ is the minimum cardinality of a resolving set. In this paper we study the metric dimension of infinite graphs such that all its vertices have finite degree. We give necessary co

C. J. Wareing, R. Hollerbach

Electron magnetohydrodynamic (EMHD) turbulence in two dimensions is studied via high-resolution numerical simulations with a normal diffusivity. The resulting energy spectra asymptotically approach a $k^{-5/2}$ law with increasing $R_B$, the ratio of the nonlinear to linear timescales in the governing equation. No evidence is found of a dissipative cutoff, c

Pierre-Emmanuel Chaput, Nicolas Perrin

We study the quantum cohomology of quasi-minuscule and quasi-cominuscule homogeneous spaces. The product of any two Schubert cells does not involve powers of the quantum parameter higher than 2. With the help of the quantum to classical principle we give presentations of the quantum cohomology algebras. These algebras are semi-simple for adjoint non coadjoin

S. Ivashyn, A. Korchin

The features of the Resonance Chiral Theory (RChT) related to the description of the lightest scalar resonances, sigma, f0(980) and a0(980), are discussed. Major attention is paid to the fits of the invariant mass distributions in the radiative decays of the phi(1020) meson. The study of the scalar sector in RChT is motivated by the success of the theory pre

Pavel V. Shevchenko

Option written on several foreign exchange rates (FXRs) depends on correlation between the rates. To evaluate the option, historical estimates for correlations can be used but usually they are not stable. More significantly, pricing of the option using these estimates is usually inconsistent to the traded vanilla contracts. To price options written on severa

N. Sandschneider, W. Nolting

We study the behaviour of the magnetization in a half-metallic ferromagnet/nonmagnetic insulator/ferromagnetic metal/paramagnetic metal (FM1/NI/FM2/PM) tunnel junction. It is calculated self-consistently within the nonequilibrium Keldysh formalism. The magnetic regions are treated as band ferromagnets and are described by the single-band Hubbard model. We de

T. Aushev

We report measurements of the branching fractions for the decays B->D_s1(2536)+ anti-D(*), where anti-D(*) is anti-D0, D- or D*-, and study of B->X(3872) K with X(3872) decaying to D*0 anti-D0 using a sample of 657 million B anti-B pairs recorded at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider.

Vadim E. Levit, Eugen Mandrescu

If alpha=alpha(G) is the maximum size of an independent set and s_{k} equals the number of stable sets of cardinality k in graph G, then I(G;x)=s_{0}+s_{1}x+...+s_{alpha}x^{alpha} is the independence polynomial of G. In this paper we prove that: 1. I(T;-1) equels either -1 or 0 or 1 for every tree T; 2. I(G;-1)=0 for every connected well-covered graph G of g

Dong Pyo Chi, Kabgyun Jeong, Taewan Kim, Kyungjin Lee

Dür [Phys. Rev. Lett. {\bf 87}, 230402 (2001)] constructed $N$-qubit bound entangled states which violate a Bell inequality for $N\ge 8$, and his result was recently improved by showing that there exists an $N$-qubit bound entangled state violating the Bell inequality if and only if $N\ge 6$ [Phys. Rev. A {\bf 79}, 032309 (2009)]. On the other hand, it has b

C. J. Cotter, G. A. Pavliotis

The problem of estimating the eddy diffusivity from Lagrangian observations in the presence of measurement error is studied in this paper. We consider a class of incompressible velocity fields for which is can be rigorously proved that the small scale dynamics can be parameterised in terms of an eddy diffusivity tensor. We show, by means of analysis and nume

G. Surcis, A. Tarchi, C. Henkel, J. Ott

Recently, a relationship between the water maser detection rate and far infrared (FIR) flux densities has been established as a result of two 22 GHz maser surveys in a complete sample of galaxies (Dec>-30 degree) with 100 micron flux densities of > 50 Jy and > 30 Jy. This survey has been extended to the southern galaxies in order to discover new maser source

Nicolau C. Saldanha, Carlos Tomei

We define cut-and-paste, a construction which, given a quadriculated disk obtains a disjoint union of quadriculated disks of smaller total area. We provide two examples of the use of this procedure as a recursive step. Tilings of a disk $\Delta$ receive a parity: we construct a perfect or near-perfect matching of tilings of opposite parities. Let $B_\Delta$

Lorenzo Zaninetti

The image of planetary nebulae is made by three different physical processes. The first process is the expansion of the shell that can be modeled by the canonical laws of motion in the spherical case and by the momentum conservation when gradients of density are present in the interstellar medium. The second process is the diffusion of particles that radiate

E. O. Kahya, V. K. Onemli, R. P. Woodard

For many quantum field theory computations in cosmology it is not possible to use the flat space trick of obtaining full, interacting states by evolving free states over infinite times. State wave functionals must be specified at finite times and, although the free states suffice to obtain the lowest order effects, higher order corrections necessarily involv

Giovanni Barontini, Michele Modugno

We investigate the stability of Bloch waves for a Bose-Einstein condensate moving through a periodic lattice created by another condensate modulated by an optical lattice. We show that the coupling of phonon-antiphonon modes of the two species give rise to a very rich structure of the regimes for dynamical instability, with significant differences with respe

Changhoon Lee, Erjun Kan, Myung-Hwan Whangbo

LaCu3Fe4O12 undergoes a phase transition at 393 K involving the spin order (SO) of the Fe sites and the charge order (CO) resulting in Cu-Fe intersite charge transfer. On the basis of density functional calculations, we show that this simultaneous CO/SO phenomenon is a consequence of two electronic effects, namely, the competition between the Fe-Fe and Fe-Cu

Alexandre I. Danilenko

It is shown that each subset of positive integers that contains 2 is realizable as the set of essential values of the multiplicity function for the Koopman operator of some weakly mixing transformation.

M. Tay, Y. H. Wu, G. C. Han, Y. B. Chen

Despite a considerable effort aiming at elucidating the nature of ferromagnetism in ZnO-based magnetic semiconductor, its origin still remains debatable. Although the observation of above room temperature ferromagnetism has been reported frequently in the literature by magnetometry measurement, so far there has been no report on correlated ferromagnetism in

W. H. T. Vlemmings, S. Goedhart, M. J. Gaylard

(Abridged) Recently, the magnetic field induced Zeeman splitting was measured for the strongest known 6.7 GHz methanol maser, which arises in the massive star forming region G09.62+0.20. This maser is one of a handful of periodically flaring methanol masers. The 100-m Effelsberg telescope was used to monitor the 6.7 GHz methanol masers of G09.62+0.20. With t

Ishwaree P Neupane

The gravity/gauge theory duality has provided us a way of studying QCD at short distances from straightforward calculations in classical general relativity. Among numerous results obtained so far, one of the most striking is the universality of the ratio of the shear viscosity to the entropy density. For all gauge theories with Einstein gravity dual, this ra

E. Oset, P. Gonzalez, M. J. Vicente Vacas, A. Ramos

We present the results of the first calculations involving the interaction of vector mesons with baryons, by means of which one generates a large amount of dynamically generated resonances, many of which can be associated to known resonances, while others represent predictions for new states.

Eric Benoit, Laurent Foulloy

If the main use of colour measurement is the metrology, it is now possible to find industrial control applications which uses this information. Using colour in process control leads to specific problems where human perception has to be replaced by colour sensors. This paper relies on the fuzzy representation of colours that can be taken into account by fuzzy

Takafumi Hatano, Teruya Ishihara, Sergei G. Tikhodeev, Nikolay A. Gippius

We discovered that when circularly polarized light is obliquely incident on a two-dimensional metallic photonic crystal slabs, electrical voltage is induced perpendicularly to the incident plane. Signal sign is reversed by changing the sense of polarization or incident angle. The origin of this transverse photo-induced voltage is explained in terms of the fo

Germano D'Abramo

A young Prince decides to explore the Father's Kingdom and aims to reach its furthermost boundaries. He starts from the City with a Caravan and seven fast and strong Messengers. They have the task to maintain the communications between the Caravan and the City during the exploration, going back and forth between the Caravan and the City while the Caravan

B. Ekta, Simon A. Pustilnik, Jayaram N. Chengalur

We present Giant Metrewave Radio Telescope (GMRT), HI 21cm observations of SBS 0335-052E and SBS 0335-052W, a close pair of dwarf galaxies, which are further unusual in being the most metal-poor star-forming galaxies known. We present images at several angular resolutions, ranging from ~40 to 4 arcsec. These images show that SBS 0335-052 is a strongly intera

N. Kida, Y. Takahashi, J. S. Lee, R. Shimano

Recent spectroscopic studies at terahertz frequencies for a variety of multiferroics endowed with both ferroelectric and magnetic orders have revealed the possible emergence of a new collective excitation, frequently referred to as electromagnon. It is magnetic origin, but becomes active in response to the electric field component of light. Here we give an o

J. Vrabec, G. K. Kedia, U. Buchhauser, R. Meyer-Pittroff

For the design and optimization of CO2 recovery from alcoholic fermentation processes by distillation, models for vapor-liquid equilibria (VLE) are needed. Two such thermodynamic models, the Peng-Robinson equation of state (EOS) and a model based on Henry's law constants, are proposed for the ternary mixture N2+O2+CO2. Pure substance parameters of the Pe

T. Schnabel, J. Vrabec, H. Hasse

noindent Henry's law constants of the solutes methane, nitrogen, oxygen and carbon dioxide in the solvent ethanol are predicted by molecular simulation. The molecular models for the solutes are taken from previous work. For the solvent ethanol, a new rigid anisotropic united atom molecular model based on Lennard-Jones and Coulombic interactions is develo

I. V. Maznichenko, A. Ernst, M. Bouhassoune, J. Henk

The structural phase transitions and the fundamental band gaps of Mg(x)Zn(1-x)O alloys are investigated by detailed first-principles calculations in the entire range of Mg concentrations x, applying a multiple-scattering theoretical approach (Korringa-Kohn-Rostoker method). Disordered alloys are treated within the coherent potential approximation (CPA). The

Vasil Michev, Naoum Karchev

We consider the two-band double exchange model for manganites with Jahn-Teller (JT) coupling and explore the suppression of the ferromagnetism because of the JT distortion. The localized spins of the $\emph{t}_{2g}$ electrons are represented in terms of the Schwinger bosons, and two spin-singlet Fermion operators are introduced instead of the $e_{g}$ electro

Houda Chafnaji, Tarik Ait-Idir, Samir Saoudi, Athanasios V. Vasilakos

In this paper, we consider high-speed wireless packet access using code division multiple access (CDMA) and multiple-input multiple-output (MIMO). Current wireless standards, such as high speed packet access (HSPA), have adopted multi-code transmission and hybrid-automatic repeat request (ARQ) as major technologies for delivering high data rates. The key tec

N. Mukunda, S. Chaturvedi, R. Simon

We present a new approach to Hamilton's theory of turns for the groups SO(3) and SU(2) which renders their properties, in particular their composition law, nearly trivial and immediately evident upon inspection. We show that the entire construction can be based on binary rotations rather than mirror reflections.

Alain Klotz, B. Gendre, J. L. Atteia, Michel Boër

We present an analysis of time-resolved optical emissions observed from the gamma-ray burst GRB 081126 during the prompt phase. The analysis employed time-resolved photometry using optical data obtained by the TAROT telescope, using BAT data from the Swift spacecraft, and time-resolved spectroscopy at high energies from the GBM instrument onboard the Fermi s

Claudia Eberlein, Robert Zietal

We derive the fully retarded energy shift of a neutral atom in two different geometries useful for modelling etched microstructures. First we calculate the energy shift due to a reflecting cylindrical wire, and then we work out the energy shift due to a semi-infinite reflecting half-plane. We analyze the results for the wire in various limits of the wire rad

G. Santangelo, L. Testi, L. Gregorini, S. Leurini

The rate of star formation both in the Galaxy and in external galaxies should be related to the physical properties of the molecular clouds from which stars form. This is expected for the starbursts found both in irregular galaxies and in some mergers. The dwarf galaxy Henize 2-10 is particularly interesting in this context as it shows a number of newly form

Jianmin Tao, Xianlong Gao, G. Vignale, I. V. Tokatly

We develop the continuum mechanics of quantum many-body systems in the linear response regime. The basic variable of the theory is the displacement field, for which we derive a closed equation of motion under the assumption that the time-dependent wave function in a locally co-moving reference frame can be described as a geometric deformation of the ground-s

Durgesh Tripathi, Bernhard Kliem, Helen E. Mason, Peter Young

Multi-wavelength observations of a sigmoidal (S-shaped) solar coronal source by the EUV Imaging Spectrometer and the X-ray Telescope aboard the Hinode spacecraft and by the EUV Imager aboard STEREO are reported. The data reveal the coexistence of a pair of J-shaped hot arcs at temperatures T>2 MK with an S-shaped structure at somewhat lower temperatures T~1.

Nicolas Vuillerme, Nicolas Pinsault

Impaired postural control has been reported in patients with chronic neck pain of both traumatic and non-traumatic etiologies, but whether painful stimulation of neck muscle per se can affect balance control during quiet standing in humans remains unclear. The purpose of the present experiment was thus to investigate the effect of experimental neck muscle pa

A. C. Selden

A series of benchmark tests of slow light in saturable absorbers is proposed. Stage I concerns experimental tests of saturable absorption, which can mimic slow light in saturable media. Stage II outlines the more demanding requirements for practical observation of spectral hole-burning in the absorption line, which is responsible for the reduction in group v

Claus Lämmerzahl, Patricia Rademaker

Interactions are explored through the observation of the dynamics of particles. On the classical level the basic underlying assumption in that scheme is that Newton's second law holds. Relaxing the validity of this axiom by, e.g., allowing for higher order time derivatives in the equations of motion would allow for a more general structure of interaction

R. Chakrabarti, S. Mukhopadhyay Krishichayan, A. Chakraborty, A. Ghosh

We report the first observation of high-spin states in nuclei in the vicinity of the "island of inversion", populated via the 18O+18O fusion reaction at an incident beam energy of 34 MeV. The fusion reaction mechanism circumvents the limitations of non-equilibrated reactions used to populate these nuclei. Detailed spin-parity measurements in these di

R. P. Mignani, A. De Luca, S. Mereghetti, P. A. Caraveo

X-ray observations reveiled a group of radio-silent isolated neutron stars (INSs) at the centre of young supernova remnants (SNRs), dubbed central compact objects or CCOs, with properties different from those of classical rotation-powered pulsars. In at least three cases, evidence points towards CCOs being low-magnetized INSs, born with slow rotation periods