October 2010 arXiv papers — page 60

J. R. Kuhn, B Geiss, D. M. Harrington

Sensitive measurements of the linearly polarized spectra of stars can be used to deduce geometric properties of their otherwise unresolved circumstellar environments. This paper describes some of the evidence for optical pumping and absorptive linear polarization and explores some interesting applications of linear spectropolarimetry for obtaining spatial in

K. Y. Cheong, Min-Hsiu Hsieh, Takeshi Koshiba

Due to the commonly known impossibility results, information theoretic security is considered impossible for oblivious transfer (OT) in both the classical and the quantum world. In this paper, we proposed a weak version of the all-or-nothing OT. In our protocol the honest parties do not need long term quantum memory, entanglements, or sophisticated quantum c

P A S Autreto, S B Legoas, M Z S Flores, D S Galvao

Recently, Lagos et al. (Nature Nanotechnology 4, 149 (2009)) reported the discovery of the smallest possible silver square cross-section nanotube. A natural question is whether similar carbon nanotubes can exist. In this work we report ab initio results for the structural, stability and electronic properties for such hypothetical structures. Our results show

Beverly J. Smith, Curtis Struck

We compare the UV-optical colors of a well-defined set of optically-selected pre-merger interacting galaxy pairs with those of normal spirals. The shorter wavelength colors show a larger dispersion for the interacting galaxies than for the spirals. This result can best be explained by higher star formation rates on average in the interacting galaxies, combin

I. Cabrera-Munguia, V. S. Manko, E. Ruiz

The general analysis of the relations between masses and angular momenta in the configurations composed of two balancing extremal Kerr particles is made on the basis of two exact solutions arising as extreme limits of the well-known double-Kerr spacetime. We show that the inequality M^2 >= |J| characteristic of an isolated Kerr black hole is verified by all

Masoud Abbaszadeh, Horacio J. Marquez

In this paper, a new method of H_infinity observer design for Lipschitz nonlinear systems is proposed in the form of an LMI optimization problem. The proposed observer has guaranteed decay rate (exponential convergence) and is robust against unknown exogenous disturbance. In addition, thanks to the linearity of the proposed LMIs in the admissible Lipschitz c

Jianhui Wang, H. A. Fertig, Ganpathy Murthy, L. Brey

We study excitonic effects in two-dimensional massless Dirac fermions with Coulomb interactions by solving the ladder approximation to the Bethe-Salpeter equation. It is found that the general 4-leg vertex has a power law behavior with the exponent going from real to complex as the coupling constant is increased. This change of behavior is manifested in the

Masaki Asano, Hyung Do Kim, Ryuichiro Kitano, Yasuhiro Shimizu

If the minimal supersymmetric standard model is the solution to the hierarchy problem, the scalar top quark (stop) and the Higgsino should weigh around the electroweak scale such as 200 GeV. A low messenger scale, which results in a light gravitino, is also suggested to suppress the quantum corrections to the Higgs mass parameters. Therefore the minimal mode

Nicola Tamanini, Carlo R. Contaldi

We examine the generation of primordial perturbations during an inflationary epoch in generalised theories of gravity when the equations of motion are derived using the Palatini variational principle. Both f(R) and Scalar-Tensor theories are considered and we compare our results with those obtained under the conventional metric formalism. Non-linear generali

J. Patrick Henry, Mara Salvato, Alexis Finoguenov, Nicolas Bouche

We have discovered an X-ray selected galaxy cluster with a spectroscopic redshift of 1.753. The redshift is of the brightest cluster galaxy (BCG), which is coincident with the peak of the X-ray surface brightness. We also have concordant photometric redshifts for seven additional candidate cluster members. The X-ray luminosity of the cluster is 3.68 +/- 0.70

A. L. Chies-Santos, S. S. Larsen, E. M. Wehner, H. Kuntschner

Context: The combination of optical and near-infrared (NIR) colours has the potential to break the age/metallicity degeneracy and offers a better metallicity sensitivity than optical colours alone. Previous studies of extragalactic globular clusters (GCs) with this colour combination, however, have suffered from small samples or have been restricted to a few

Walter Van Herck

In arXiv:0909.0508 D-particle degeneracies were calculated using novel methods. By analysing this refined computation of the index in the setting of the topological B model, a correspondence is found between flow trees in the supergravity description and B-branes in the topological theory. This enables us to use the same refinement also for single flows. A c

Geoffrey Compère, Wei Song, Amitabh Virmani

We show that the spinning magnetic one-brane in minimal five-dimensional supergravity admits a decoupling limit that interpolates smoothly between a self-dual null orbifold of AdS_3 \times S^2 and the near-horizon limit of the extremal Kerr black hole times a circle. We use this interpolating solution to understand the field theory dual to spinning M5 branes

Alessandro Ridolfo, Rocco Vilardi, Omar Di Stefano, Stefano Portolan

We study the all-optical time-control of the strong coupling between a single cascade three-level quantum emitter and a microcavity. We find that only specific arrival-times of the control pulses succeed in switching-off the Rabi oscillations. Depending on the arrival times of control pulses, a variety of exotic non-adiabatic cavity quantum electrodynamics e

Kelly Foyle, Hans-Walter Rix, Fabian Walter, Adam Leroy

We investigate the relationship between spiral arms and star formation in the grand-design spirals NGC 5194 and NGC 628 and in the flocculent spiral NGC 6946. Filtered maps of near-IR (3.6 micron) emission allow us to identify "arm regions" that should correspond to regions of stellar mass density enhancements. The two grand-design spirals show a cle

Wiphu Rujopakarn, George H. Rieke, Daniel J. Eisenstein, Stephanie Juneau

We show that the star-forming regions in high-redshift luminous and ultraluminous infrared galaxies (LIRGs and ULIRGs) and submillimeter galaxies (SMGs) have similar physical scales to those in local normal star-forming galaxies. To first order, their higher infrared (IR) luminosities result from higher luminosity surface density. We also find a good correla

Jeffrey Berger, Anna Stasto

Nonlinear evolution equation at small x with impact parameter dependence is analyzed numerically. Saturation scales and the radius of expansion in impact parameter are extracted as functions of rapidity. Running coupling is included in this evolution, and it is found that the solution is sensitive to the infrared regularization. Kinematical effects beyond le

D. A. Abanin, D. A. Pesin

We study collective behavior of magnetic adatoms randomly distributed on the surface of a topological insulator. As a consequence of the spin-momentum locking on the surface, the RKKY-type interactions of two adatom spins depend on the direction of the vector connecting them, thus interactions of an ensemble of adatoms are frustrated. We show that at low tem

P. A. Fridman

A method of radio frequency interference (RFI) suppression in radio astronomy spectral observations is described based on the analysis of the probability distribution of an instantaneous spectrum. This method allows the separation of the gaussian component due to the natural radio source and the non-gaussian RFI signal. Examples are presented in the form of

L. E. Young S., L. Salasnich, S. K. Adhikari

We present effective reduced equations for the study of a binary Bose-Einstein condensate (BEC), where the confining potentials of the two BEC components have distinct asymmetry so that the components belong to different space dimensions as in a recent experiment [G. Lamporesi et al., Phys. Rev. Lett. 104, 153202 (2010)]. Starting from a binary three-dimensi

Philip T. Gressman

This paper is concerned with establishing uniform weighted $L^p$-$L^q$ estimates for a class of operators generalizing both Radon-like operators and sublevel set operators. Such estimates are shown to hold under general circumstances whenever a scalar inequality holds for certain associated measures (the inequality is of the sort studied by Oberlin, relating

Daniel F. Santavicca, Joel D. Chudow, Daniel E. Prober, Meninder S. Purewal

We characterize the energy loss of the non-equilibrium electron system in individual metallic single-walled carbon nanotubes at low temperature. Using Johnson noise thermometry, we demonstrate that, for a nanotube with ohmic contacts, the dc resistance at finite bias current directly reflects the average electron temperature. This enables a straightforward d

J. R. Petta, H. Lu, A. C. Gossard

Rapid coherent control of electron spin states is required for implementation of a spin-based quantum processor. We demonstrate coherent control of electronic spin states in a double quantum dot by sweeping an initially prepared spin singlet state through a singlet-triplet anti-crossing in the energy level spectrum. The anti-crossing serves as a beam splitte

Yang-Hui He

The examination of roots of constrained polynomials dates back at least to Waring and to Littlewood. However, such delicate structures as fractals and holes have only recently been found. We study the space of roots to certain integer polynomials arising naturally in the context of Calabi-Yau spaces, notably Poincare and Newton polynomials, and observe vario

Filomena Volino, Olaf Wucknitz, John P. McKean, Michael A. Garrett

The 8 o'clock arc is a gravitationally lensed Lyman Break Galaxy (LBG) at redshift z=2.73 that has a star-formation rate (SFR) of 270 solar-mass/year (derived from optical and near-infrared spectroscopy). Taking the magnification of the system ~12 and the SFR into account, the expected flux density of any associated radio emission at 1.4 GHz is predicted

Michelle Effros, Tracey Ho, Shirin Jalali

One major open problem in network coding is to characterize the capacity region of a general multi-source multi-demand network. There are some existing computational tools for bounding the capacity of general networks, but their computational complexity grows very quickly with the size of the network. This motivates us to propose a new hierarchical approach

Vladimir Kovalevsky

The paper presents a new set of axioms of digital topology, which are easily understandable for application developers. They define a class of locally finite (LF) topological spaces. An important property of LF spaces satisfying the axioms is that the neighborhood relation is antisymmetric and transitive. Therefore any connected and non-trivial LF space is i

A. V. Ershov

In the present paper we study a bordism theory related to pairs $(M,\, ξ),$ where $M$ is a closed smooth oriented manifold with a stably trivial normal bundle and $ξ$ is a virtual $\SU$-bundle of virtual dimension 1 over $M$. The main result is the calculation of the corresponding ring modulo torsion and the explicit description of its generators.

The QUBIC collaboration, E. Battistelli, A. Baù, D. Bennett

One of the major challenges of modern cosmology is the detection of B-mode polarization anisotropies in the CMB. These originate from tensor fluctuations of the metric produced during the inflationary phase. Their detection would therefore constitute a major step towards understanding the primordial Universe. The expected level of these anisotropies is howev

Nicholas S. Manton, Nuno M. Romão

We investigate the geometry of the moduli space of N-vortices on line bundles over a closed Riemann surface of genus g > 1, in the little explored situation where 1 =< N < g. In the regime where the area of the surface is just large enough to accommodate N vortices (which we call the dissolving limit), we describe the relation between the geometry of the mod

Zheng Wang, Jie Luo

A new channel coding approach was proposed in [1] for random multiple access communication over the discrete-time memoryless channel. The coding approach allows users to choose their communication rates independently without sharing the rate information among each other or with the receiver. The receiver will either decode the message or report a collision d

Hsiao-Ping Hsu, Wolfgang Paul, Kurt Binder

When the local intrinsic stiffness of a polymer chain varies over a wide range, one can observe both a crossover from rigid-rod-like behavior to (almost) Gaussian random coils and a further crossover towards self-avoiding walks in good solvents. Using the pruned-enriched Rosenbluth method (PERM) to study self-avoiding walks of up to $N_b=50000$ steps and var

Marc van der Sluys, Michael Politano, Ronald E. Taam

We present basic properties of primary stars that initiate a common envelope (CE) in a binary, while on the giant branch. We use the population-synthesis code described in Politano et al. (2010) and follow the evolution of a population of binary stars up to the point where the primary fills its Roche lobe and initiates a CE. We then collect the properties of

A. Crisanti, C. De Dominicis

We study the spectrum of the Hessian of the Sherrington-Kirkpatrick model near T=0, whose eigenvalues are the masses of the bare propagators in the expansion around the mean-field solution. In the limit $T\ll 1$ two regions can be identified. The first for $x$ close to 0, where $x$ is the Parisi replica symmetry breaking scheme parameter. In this region the

David B. Cline

We briefly review the constraints on the search for low mass wimps (< 15 GeV) and the various experimental methods. These experiments depend on the response of detectors to low energy signals (less than 15 KeV equivalent energy). We then describe recent fits to the data and attempt to determine Leff, the energy response at low energy. We find that the use of

Julio F. Fernandez

By tempered Monte Carlo simulations, an Almeida-Thouless (AT) phase-boundary line in site-diluted Ising spin systems is searched for. Spins interact only through dipolar fields and occupy a small fraction of lattice sites. The spin-glass susceptibility of these systems and of the Sherrington-Kirkpatrick model are compared. The correlation length as a functio

G. D&#39;Agostini

This paper reviews the basic ideas behind a Bayesian unfolding published some years ago and improves their implementation. In particular, uncertainties are now treated at all levels by probability density functions and their propagation is performed by Monte Carlo integration. Thus, small numbers are better handled and the final uncertainty does not rely on

A. Szameit, Y. Shechtman, H. Dana, S. Steiner

We present the experimental reconstruction of sub-wavelength features from the far-field of sparse optical objects. We show that it is sufficient to know that the object is sparse, and only that, and recover 100 nm features with the resolution of 30 nm, for an illuminating wavelength of λ=532 nm. Our technique works in real-time, requires no scanning, and ca

Petteri Mannersalo, Georgios S. Paschos, Lazaros Gkatzikis

This paper focuses on a particular transmission scheme called local network coding, which has been reported to provide significant performance gains in practical wireless networks. The performance of this scheme strongly depends on the network topology and thus on the locations of the wireless nodes. Also, it has been shown previously that finding the encodi

Matteo Dell&#39;Amico, Pietro Michiardi, Yves Roudier

Correlation in user connectivity patterns is generally considered a problem for system designers, since it results in peaks of demand and also in the scarcity of resources for peer-to-peer applications. The other side of the coin is that these connectivity patterns are often predictable and that, to some extent, they can be dealt with proactively. In this wo

Michael Albrow

I discuss Double Pomeron Exchange processes from their first observation at the CERN Intersecting Storage Rings, focusing on glueball searches, through the observations of exclusive chi_c, photon-photon, and di-jets at the Tevatron, to prospects at the LHC for exclusive Higgs boson production.

Gabriel H. Tucci, Philip A. Whiting

This paper centers on the limit eigenvalue distribution for random Vandermonde matrices with unit magnitude complex entries. The phases of the entries are chosen independently and identically distributed from the interval $[-π,π]$. Various types of distribution for the phase are considered and we establish the existence of the empirical eigenvalue distributi

Daniel R. Phillips

I discuss the conditions under which the application of chiral perturbation theory to the NN potential gives reliable results for NN scattering phase shifts. ChiPT also yields a convergent expansion for the deuteron charge operator. For cutoffs < 1 GeV, this produces precise predictions for deuterium&#39;s quadrupole and charge form factors in the range Q^2

Richard L. Hall, Nasser Saad, Ozlem Yesiltas

We present a supersymmetric analysis for the d-dimensional Schroedinger equation with the generalized isotonic nonlinear-oscillator potential V(r)={B^2}/{r^{2}}+ω^{2} r^{2}+2g{(r^{2}-a^{2})}/{(r^{2}+a^{2})^{2}}, B\geq 0. We show that the eigenequation for this potential is exactly solvable provided g=2 and (ωa^2)^2 = B^2 +(\ell +(d-2)/2)^2. Under these condi

J. Silva Lobo

The Skyrme crystal, a solution of the Skyrme model, is the lowest energy-per-charge configuration of skyrmions seen so far. Our numerical investigations show that, as the period in various space directions is changed, one obtains various other configurations, such as a double square wall, and parallel vortex-like solutions. We also show that there is a sudde

Yifang Fan, Yubo Fan, Zhiyu Lin, Changsheng Lv

Bone surface mapping technique is proposed on the bases of two kinds of uniqueness of bone in vivo, (i) magnitude of the principal moments of inertia, (ii) the direction cosines of principal axes of inertia relative to inertia reference frame. We choose the principal axes of inertia as the bone coordinate system axes. The geographical marks such as the prime

L. Chemin, C. Soubiran, F. Crifo, G. Jasniewicz

A new full-sky catalog of Radial Velocity standard stars is being built for the determination of the Radial Velocity Zero Point of the RVS on board of Gaia. After a careful selection of 1420 candidates matching well defined criteria, we are now observing all of them to verify that they are stable enough over several years to be qualified as reference stars.

F. Crifo, G. Jasniewicz, C. Soubiran, D. Katz

The calibration of the Radial Velocity Spectrometer (RVS) onboard the ESA Gaia satellite (to be launched in 2012) requires a list of standard stars with a radial velocity (RV) known with an accuracy of at least 300 m/s. The IAU Commission 30 lists of RV standard stars are too bright and not dense enough. We describe the selection criteria due to the RVS cons

J. -F. Desmurs, A. Baudry, P. Sivagnanam, C. Henkel

The aim of this study is to investigate the physical properties of molecular envelopes of planetary nebulae in their earliest stages of evolution. Using the 100m telescope at Effelsberg, we have undertaken a high sensitivity discrete source survey for the first excited state of OH maser emission (J=5/2, 2PI3/2 at 6GHz) in the direction of planetary and proto

P. S. Burada, G. Schmid

We propose a new mechanism to alter the nature of the potential barriers when a biased Brownian particle under goes a constrained motion in narrow, periodic channel. By changing the angle of the external bias, the nature of the potential barriers changes from purely entropic to energetic which in turn effects the diffusion process in the system. At an optimu

Ewan O&#39;Sullivan, Simona Giacintucci, Laurence P. David, Jan M. Vrtilek

We use a Chandra observation of the poor cluster AWM4 to map the temperature and abundance of the intra-cluster medium, so as to examine the influence of the central radio galaxy on its environment. While the cluster core is generally enriched to near-solar abundances, we find evidence of super-solar abundances correlated with the radio jets, extending ~35 k

George Theodorakopoulos, Jean-Yves Le Boudec, John S. Baras

An epidemic spreading in a network calls for a decision on the part of the network members: They should decide whether to protect themselves or not. Their decision depends on the trade-off between their perceived risk of being infected and the cost of being protected. The network members can make decisions repeatedly, based on information that they receive a

Aruna N. Ramanayaka, R. G. Mani

Transport measurements indicate strong oscillations in the Hall-,$R_{xy}$, and the diagonal-, $R_{xx}$, resistances and exhibit Hall plateaus at the lowest temperatures, in three-dimensional Highly Oriented Pyrolytic Graphite (HOPG). At the same time, a comparative Shubnikov-de Haas-oscillations-based Berry&#39;s phase analysis indicates that graphite is unl

S Satheesh, E Sandhya

The notion of random self-decomposability is generalized further. The notion is then extended to non-negative integer-valued distributions.

Thomas L. Marzetta, Gabriel H. Tucci, Steven H. Simon

In many practical situations we would like to estimate the covariance matrix of a set of variables from an insufficient amount of data. More specifically, if we have a set of $N$ independent, identically distributed measurements of an $M$ dimensional random vector the maximum likelihood estimate is the sample covariance matrix. Here we consider the case wher

Sergey Neshveyev

We give a description of traces on C(X)\rtimes G in terms of measurable fields of traces on the C*-algebras of the stabilizers of the action of G on X.

Marcelo Laca, Sergey Neshveyev

We complete the analysis of KMS-states of the Toeplitz algebra of the affine semigroup over the natural numbers, recently studied by Raeburn and the first author, by showing that for every inverse temperature beta in the critical interval [1,2], the unique KMS_beta-state is of type III_1. We prove this by reducing the type classification from the Toeplitz al

Arnaud Dupays, Carlo Rizzo, Bignami Giovanni Fabrizio

In this letter we show that Quantum Vacuum Friction (QVF) should play an important role in neutron star evolution. Taking into account this effect we show that magnetars could be understood as a natural evolution of standard pulsars. For the Crab pulsar, of which the characteristic age is known, we present the first completely coherent time evolution for its

Angel Alastuey

The study of quantum Coulomb systems at equilibrium is important for understanding properties of matter in many physical situations. Screening, recombination and van der Waals forces are basic phenomena which result from the interplay of Coulomb interactions, collective effects and quantum mechanics. Those phenomena are introduced in the first part of this l

R. J. Samworth, M. P. Wand

We study kernel estimation of highest-density regions (HDR). Our main contributions are two-fold. First, we derive a uniform-in-bandwidth asymptotic approximation to a risk that is appropriate for HDR estimation. This approximation is then used to derive a bandwidth selection rule for HDR estimation possessing attractive asymptotic properties. We also presen

Pratim Kumar Chattaraj, Sateesh Bandaru, Sukanta Mondal

Structure, stability and reactivity of clathrate hydrates with or without hydrogen encapsulation are studied using standard density functional calculations. Conceptual density functional theory based reactivity descriptors and the associated electronic structure principles are used to explain the hydrogen storage properties of clathrate hydrates. Different t

Tanja Branz, Raquel Molina, Eulogio Oset

We study the radiative decay properties of the charmonium-like X, Y and Z mesons generated dynamically from vector meson-vector meson interaction in the framework of a unitarized hidden-gauge formalism. In the present work we calculate the one- and two-photon decay widths of the hidden-charm Y(3940), Z(3930) (or X(3915)) and X(4160) mesons in the framework o

Oriol T. Valls, Matthew Bryan, Igor Zutic

Studies of the superconducting proximity effect in normal conductor/superconductor $(N/S)$ junctions almost universally assume no effective electron-electron coupling in the $N$ region. While such an approximation leads to a simple description of the proximity effect, it is unclear how it could be rigorously justified. We reveal a much more complex picture o

B. Hatsukade, K. Kohno, I. Aretxaga, J. E. Austermann

We present results of a 1.1 mm deep survey of the AKARI Deep Field South (ADF-S) with AzTEC mounted on the Atacama Submillimetre Telescope Experiment (ASTE). We obtained a map of 0.25 sq. deg area with an rms noise level of 0.32-0.71 mJy. This is one of the deepest and widest maps thus far at millimetre and submillimetre wavelengths. We uncovered 198 sources

R. A. Anikin, A. V. Kuznetsov, N. V. Mikheev

We analyze the influence of neutrino helicity conversion, $ν_L \to ν_R$, on the neutrino flux from a supernova caused by the interaction of the Dirac neutrino magnetic moment with a magnetic field. We show that if the neutrino has a magnetic moment in the interval $10^{-13} \, μ_{\rm B} < μ_ν< 10^{-12} \, μ_{\rm B}$ and provided that a magnetic field of $\si

A. V. Kuznetsov, N. V. Mikheev, A. V. Serghienko

The width of the neutrino decay into the electron and $W$ boson in a strong external magnetic field is obtained from the imaginary part of the neutrino self-energy. This result corrects the formulae existing in the literature. The mean free path of an ultra-high energy neutrino in a strong magnetic field is calculated. An energy cutoff for neutrinos propagat

Andriy Norets

This paper shows that large nonparametric classes of conditional multivariate densities can be approximated in the Kullback--Leibler distance by different specifications of finite mixtures of normal regressions in which normal means and variances and mixing probabilities can depend on variables in the conditioning set (covariates). These models are a special

Guo-Chin Liu, Mark Birkinshaw, Jiun-Huei Proty Wu, Paul T. P. Ho

We investigate the contamination of the Sunyaev--Zel&#39;dovich (SZ) effect for six galaxy clusters, A1689, A1995, A2142, A2163, A2261, and A2390, observed by the Y. T. Lee Array for Microwave Background Anisotropy during 2007. With the range of baselines used, we find that the largest effect (of order 13%-50% of the central SZ flux density) comes from prima

Guo-Chin Liu, Kin-Wang Ng, Ue-Li Pen

Integrated Sachs-Wolfe (ISW) effect can be estimated by cross-correlating Cosmic Microwave Background (CMB) sky with tracers of the local matter distribution. At late cosmic time, the dark energy induced decay of gravitation potential generates a cross-correlation signal on large angular scales. The dominant noise are the intrinsic CMB anisotropies from the

I W Martin, R Bassiri, R Nawrodt, M M Fejer

Thermal noise arising from mechanical dissipation in dielectric reflective coatings is expected to critically limit the sensitivity of precision measurement systems such as high-resolution optical spectroscopy, optical frequency standards and future generations of interferometric gravitational wave detectors. We present measurements of the effect of post-dep

M. Bendele, P. Babkevich, S. Katrych, S. N. Gvasaliya

The superconducting and magnetic properties of Fe$_{y}$Se$_{0.25}$Te$_{0.75}$ single crystals ($0.9\leq y \leq1.1$) were studied by means of x-ray diffraction, SQUID magnetometry, muon spin rotation, and elastic neutron diffraction. The samples with $y<1$ exhibit coexistence of bulk superconductivity and incommensurate magnetism. The magnetic order remains i

G. Brodin, M. Marklund, J. Zamanian, M. Stefan

We give a short review of a number of different models for treating magnetization effects in plasmas. In particular, the transition between kinetic models and fluid models is discussed. We also give examples of applications of such theories. Some future aspects are discussed.

Floris Reurings, Filip Tuomisto, Chad S. Gallinat, Gregor Koblmüller

The authors have applied positron annihilation spectroscopy to study the effect of different growth conditions on vacancy formation in In- and N-polar InN grown by plasma-assisted molecular beam epitaxy. The results suggest that the structural quality of the material and limited diffusion of surface adatoms during growth dictate the In vacancy formation in l

Alexander A. Kovalevsky

We give examples of $L^{1}$-functions that are essentially unbounded on every nonempty open subset of their domains of definition. We obtain such functions as limits of weighted sums of functions with the unboundedly increasing number of singular points lying at the nodes of standard compressible periodic grids in $\Bbb R^n$. Moreover, we prove that the latt

Stefano Frixione, Fabian Stoeckli, Paolo Torrielli, Bryan R. Webber

We present the calculations necessary to obtain next-to-leading order QCD precision with the Herwig++ event generator using the MC@NLO approach, and implement them for all the processes that were previously available from Fortran HERWIG with MC@NLO. We show a range of results comparing the two implementations. With these calculations and recent developments

Marc Burger, Narutaka Ozawa, Andreas Thom

We study $ε$-representations of discrete groups by unitary operators on a Hilbert space. We define the notion of Ulam stability of a group which loosely means that finite-dimensional $ε$-represendations are uniformly close to unitary representations. One of our main results is that certain lattices in connected semi-simple Lie groups of higher rank are Ulam

P. Mandal, M. Mukherjee

An entangled state prepared in a decoherence free sub-space together with a Ramsey type measurement can probe parity violation in heavy alkali ions like Ba+ or Ra+. Here we propose an experiment with Ba+ as an example to measure the small parity violating effect in this system. It has been shown that a measurement on a maximally correlated system will reduce

S. Gluzman, V. I. Yukalov

The problem is addressed of defining the values of functions, whose variables tend to infinity, from the knowledge of these functions at asymptotically small variables close to zero. For this purpose, the extrapolation by means of different types of self-similar approximants is employed. Two new variants of such an extrapolation are suggested. The methods ar

Somayeh Abdi, Hossein Pedram, Somayeh Mohamadi

In data-intensive applications data transfer is a primary cause of job execution delay. Data access time depends on bandwidth. The major bottleneck to supporting fast data access in Grids is the high latencies of Wide Area Networks and Internet. Effective scheduling can reduce the amount of data transferred across the internet by dispatching a job to where t

Bernhard Haeupler

We give a new technique to analyze the stopping time of gossip protocols that are based on random linear network coding (RLNC). Our analysis drastically simplifies, extends and strengthens previous results. We analyze RLNC gossip in a general framework for network and communication models that encompasses and unifies the models used previously in this contex

Andrew Adamatzky, Genaro J. Martinez, Sergio V. Chapa-Vergara, Rene Asomoza-Palacio

Plasmodium of Physarum polycephalum is a single cell visible by unaided eye. During its foraging behavior the cell spans spatially distributed sources of nutrients with a protoplasmic network. Geometrical structure of the protoplasmic networks allows the plasmodium to optimize transport of nutrients between remote parts of its body. Assuming major Mexican ci

Victor Abrashkin, Ruth Jenni

The field-of-norms functor is applied to deduce explicit reciprocity formulae for the Hilbert symbol in the mixed characteristic case from the explicit formula for the Witt symbol in characteristic p > 2 in the context of higher local fields. Is is shown that a &#34;very special case&#34; of this construction gives Vostokov&#39;s explicit formula

Rolf Kappl, Michael Ratz, Martin Wolfgang Winkler

We discuss the possibility of light dark matter in a general singlet extension of the MSSM. Singlino LSPs with masses of a few GeV can explain the signals reported by the CRESST, CoGeNT and possibly also DAMA experiments. The interactions between singlinos and nuclei are mediated by a scalar whose properties coincide with those of the SM Higgs up to two cruc

W. Beyn, B. Gess, P. Lescot, M. Röckner

We prove new $L^2$-estimates and regularity results for generalized porous media equations &#34;shifted by&#34; a function-valued Wiener path. To include Wiener paths with merely first spatial (weak) derivates we introduce the notion of &#34;$ζ$-monotonicity&#34; for the non-linear function in the equation. As a consequence we prove that stochastic porous me

S. Chattopadhyay, S. K. Neogi, A. Sarkar, M. D. Mukadam

Single phase Mn doped (2 at %) ZnO samples have been synthesized by solid-state reaction technique. Before the final sintering at 500 C, the mixed powders have been milled for different milling periods (6, 24, 48 and 96 hours). The grain sizes of the samples are very close to each other (~ 32 \pm 4 nm). However, the defective state of the samples is differen

Andreas Heithausen, Christoph Böttner

The association of young T Tauri stars, MBM12A, indicates that L1457 was forming stars not too long ago. With our study we want to find out whether or not there are still signs for ongoing star formation in that cloud. Using the Max-Planck-Millimeter-Bolometer MAMBO at the IRAM 30m telescope we obtained a map of about 8&#39; by 8&#39; centered on L1457 in th

Venkata Aditya Cherikuri, B. G. Sidharth

We consider the Proca equation which is the Maxwell equation of electromagnetism for a massive particle, in the ultra relativistic limit using Snyder-Sidharth Hamiltonian. There is now an extra parity non-conserving term and we investigate the consequence both for the Proca equation and the Maxwell equation.

Emma Teresa Whelan, Francesca Bacciotti, Tom Ray, Catherine Dougados

Recently it has become apparent that proto-stellar-like outflow activity extends to the brown dwarf (BD) mass regime. While the presence of accretion appears to be the common ingredient in all objects known to drive jets fundamental questions remain unanswered. The more prominent being the exact mechanism by which jets are launched, and whether this mechanis

G. Cortiana

The search for first top-quark pair candidate events and the related background studies using data-driven techniques are reported for about 300 inverse nb of 7 TeV proton-proton collision data delivered by the Large Hadron Collider (LHC) and collected with the ATLAS detector. Selected events are characterized by the presence of high-pT isolated charged lepto

Lev P. Pitaevskii

It is shown that the violation of the positiveness of the entropy due to the Casimir-Lifshitz interaction claimed in several papers is an artifact related to an improper interpretation of the &#34;Casimir entropy&#34;, which actually is a difference of two positive terms. It is explained that at definite condition this &#34;Casimir entropy&#34; must be negat

Amy Novick-Cohen, Andrey Shishkov

In this paper, we focus on the thin film equation with lower order &#34;backwards&#34; diffusion which can describe, for example, the evolution of thin viscous films in the presence of gravity and thermo-capillary effects, or the thin film equation with a &#34;porous media cutoff&#34; of van der Waals forces. We treat in detail the equation $$u_t + \{u^n(u_{

Sanjay Gosain

We study the distribution of magnetic shear in an emerging flux region using the high-resolution Hinode/SOT SP observations. The distribution of mean magnetic shear angle across the active region shows large values near region of flux emergence i.e., in the middle of existing bipolar region and decreases while approaching the periphery of the active region.

Kazuma Nakamura, Ryotaro Arita, Hiroaki Ikeda

We present a systematic ab initio study based on density-functional calculations to understand impurity effects in iron-based superconductors. Effective tight-binding Hamiltonians for the d-bands of LaFeAsO with various transition-metal impurities such as Mn, Co, Ni, Zn, and Ru are constructed using maximally-localized Wannier orbitals. Local electronic stru

Sanjay Gosain, P. Venkatakrishnan

We study the evolution of magnetic shear angle in a flare productive active region NOAA 10930. The magnetic shear angle is defined as the deviation in the orientation of the observed magnetic field vector with respect to the potential field vector. The shear angle is measured in horizontal as well as vertical plane. The former is computed by taking the diffe

Daniel M. Oberlin

We prove a Fourier restriction result, uniform over a certain collection of reference measures, for some indices in the Stein-Tomas range.

Jae-Hyeon Parq, Jaejun Yu, Gunn Kim

Using density functional calculations, we investigate the structural and magnetic properties of ultrathin Gd and Gd-carbide nanowires (NWs) encapsulated in narrow carbon nanotubes (CNTs). The equilibrium geometry of an encapsulated (2 \times 2) Gd-NW is markedly different from that of bulk Gd crystals. The charge-density analysis shows pronounced spin-depend

E. S. Annibale, O. Fialko, K. Ziegler

We study a mixture of two light spin-1/2 fermionic atoms and two heavy atoms %in a Mott state in a double well potential. Inelastic scattering processes between both atomic species excite the heavy atoms and renormalize the tunneling rate and the interaction of the light atoms (polaron effect). The effective interaction of the light atoms changes its sign an

J. Yamagata-Sekihara, L. Roca, E. Oset

We show that the $K^*_2(1430)$, $K^*_3(1780)$, $K^*_4(2045)$, $K^*_5(2380)$ and a not yet discovered $K_6^*$ resonance are basically molecules made of an increasing number of $ρ(770)$ and one $K^*(892)$ mesons. The idea relies on the fact that the vector-vector interaction in s-wave with spins aligned is very strong both for $ρρ$ and $K^*ρ$. We extend a rece

Tom Britton, Pieter Trapman

We consider two classes of random graphs: $(a)$ Poissonian random graphs in which the $n$ vertices in the graph have i.i.d.\ weights distributed as $X$, where $\mathbb{E}(X) = μ$. Edges are added according to a product measure and the probability that a vertex of weight $x$ shares and edge with a vertex of weight $y$ is given by $1-e^{-xy/(μn)}$. $(b)$ A thi

Valerio Scarani

I review the ideas and main results in the derivation of security bounds in quantum key distribution for keys of finite length. In particular, all the detailed studies on specific protocols and implementations indicate that no secret key can be extracted if the number of processed signals per run is smaller than 10^5-10^6. I show how these numbers can be rec