May 2009 arXiv papers — page 34

Agnieszka B. Malinowska, Delfim F. M. Torres

We introduce the notion of strong local minimizer for the problems of the calculus of variations on time scales. Simple examples show that on a time scale a weak minimum is not necessarily a strong minimum. A time scale form of the Weierstrass necessary optimality condition is proved, which enables to include and generalize in the same result both continuous

D. R. Heath-Brown

It is shown, subject to the abc-conjecture, that \[\sum_{n\le N}\exp(2πiαn^3)\ll_{ε,α}N^{5/7+ε}\] for any $ε>0$ and any quadratic irrational $α$.

V. Hung Nguyen, V. Nam Do, A. Bournel, V. Lien Nguyen

Using the non-equilibrium Green's functions formalism in a tight binding model, the spin-dependent transport in armchair graphene nanoribbon (GNR) structures controlled by a ferromagnetic gate is investigated. Beyond the oscillatory behavior of conductance and spin polarization with respect to the barrier height, which can be tuned by the gate voltage, w

Jeremy Shears, David Boyd, Tut Campbell, Shawn Dvorak

We report photometry of V358 Lyr during its 2008 November outburst, the first confirmed outburst since 1965. At its brightest the star was V=15.9 and the outburst amplitude was at least 7.3 magnitudes and lasted at least 23 days. The first 4 days of the outburst corresponded to the plateau phase and the star then faded at 0.13 mag/d over the next 7 days. The

Koji Tsumura

In this paper, we examine the optimal quantization of signals for system identification. We deal with memoryless quantization for the output signals and derive the optimal quantization schemes. The objective functions are the errors of least squares parameter estimation subject to a constraint on the number of subsections of the quantized signals or the expe

Fabrizio Colombo, Graziano Gentili, Irene Sabadini, Daniele C. Struppa

In this paper we prove a new representation formula for slice regular functions, which shows that the value of a slice regular function $f$ at a point $q=x+yI$ can be recovered by the values of $f$ at the points $q+yJ$ and $q+yK$ for any choice of imaginary units $I, J, K.$ This result allows us to extend the known properties of slice regular functions defin

Franz Lehner

Noncommutative invariant theory is a generalization of the classical invariant theory of the action of $SL(2,\IC)$ on binary forms. The dimensions of the spaces of invariant noncommutative polynomials coincide with the numbers of certain noncrossing partitions. We give an elementary combinatorial explanation of this fact by constructing a noncrossing basis o

J. West

The time dilation of non-inertial travelers in circular and polygonal closed paths are well known. In both cases observers completing a round trip will age less than an observer at rest with respect to the circle / polygon. This rapid aging is contrary to the slow aging that would be documented by temporarily comoving inertial observers who might also move a

Jos Zwanikken, René van Roij

Within a modified Poisson-Boltzmann theory we study the effect of Bjerrum pairs on the typical length scale $1/\barκ$ over which electric fields are screened in electrolyte solutions, taking into account a simple association-dissociation equilibrium between free ions and Bjerrum pairs. At low densities of Bjerrum pairs, this length scale is well approximated

Irapuan Rodrigues, Horacio Dottori, Ruben J. Diaz, Maria P. Aguero

Two-dimensional kinematics of the central region of M 83 (NGC 5236) were obtained through three-dimensional NIR spectroscopy with Gemini South telescope. The spatial region covered by the integral field unit (~5" x 13" or ~90 x 240 pc), was centered approximately at the center of the bulge isophotes and oriented SE-NW. The Pa_beta emission at half ar

G. I. G. Jozsa, M. A. Garrett, T. A. Oosterloo, H. Rampadarath

We present multi-wavelength radio observations in the direction of the spiral galaxy IC 2497 and the neighbouring emission nebula known as "Hanny's Voorwerp". Our WSRT continuum observations at 1.4 GHz and 4.9 GHz, reveal the presence of extended emission at the position of the nebulosity, although the bulk of the emission remains unresolved at t

L. Tolos, D. Gamermann, R. Molina, E. Oset

Charmed mesons in hot and dense matter are studied within a self-consistent coupled-channel approach for the experimental conditions of density and temperature expected at the CBM experiment at FAIR/GSI. The $D$ meson spectral function broadens with increasing density with an extended tail towards lower energies due to $Λ_c(2593) N^{-1}$ and $Σ_c(2800) N^{-1

Chuan-Jia Shan, Wei-Wen Cheng, Ji-Bing Liu, Tang-Kun Liu

Jordan-Wigner transformation and Bogolyubov transformation are the main steps of the diagonalization of Hamiltonian and paly an important role in the statistical mechanics calculations for one-dimensional Heisenberg spin chain model. Many methods can be exploited as a tool to detect quantum phase transition, regions of criticality and scaling behavior in the

St. Raetz, M. Vanko, M. Mugrauer, T. O. B. Schmidt

We report on observations of the eclipsing binary 2MASS 19090585+4911585 with the 25 cm auxiliary telescope of the University Observatory Jena. We show that a nearby brighter star (2MASS 19090783+4912085) was previously misclassified as the eclipsing binary and find 2MASS 19090585+4911585 to be the true source of variation. We present photometric analysis of

St. Raetz, M. Mugrauer, T. O. B. Schmidt, T. Roell

We report on observations of several transit events of the transiting planet TrES-2 obtained with the Cassegrain-Teleskop-Kamera at the University Observatory Jena. Between March 2007 and November 2008 ten different transits and almost a complete orbital period were observed. Overall, in 40 nights of observation 4291 exposures (in total 71.52 h of observatio

V. D'Orazi, S. Randich, E. Flaccomio, F. Palla

Determining the metal content of low-mass members of young associations provides a tool that addresses different issues, such as triggered star formation or the link between the metal-rich nature of planet-host stars and the early phases of planet formation. The Orion complex is a well known example of possible triggered star formation and is known to host a

A. Koeltzsch, M. Mugrauer, St. Raetz, T. O. B. Schmidt

We report on observation and determination of rotational periods of ten weak-line T Tauri stars in the Cepheus-Cassiopeia star-forming region. Observations were carried out with the Cassegrain-Teleskop-Kamera (CTK) at University Observatory Jena between 2007 June and 2008 May. The periods obtained range between 0.49 d and 5.7 d, typical for weak-line and pos

Zhenhua Yu, Georg M. Bruun, Gordon Baym

We relate short-range correlations in ultracold atomic Fermi gases to the entropy of the system over the entire temperature, $T$, vs. coupling strength, $-1/k_Fa$, plane. In the low temperature limit the entropy is dominated by phonon excitations and the correlations increase as $T^4$. In the BEC limit, we calculate a boson model within the Bogoliubov approx

Valentina D'Orazi, Sofia Randich

Galactic open clusters have been long recognized as one of the best tools to investigate the chemical content of Galactic disk and its time evolution. In the last decade, many efforts have been directed to chemically characterize the old and intermediate age population; surprisingly, the chemical content of the younger and close counterpart remains largely u

Almut Burchard, Marina Chugunova

We study the problem of finding the instability index of certain non-selfadjoint fourth order differential operators that appear as linearizations of coating and rimming flows, where a thin layer of fluid coats a horizontal rotating cylinder. The main result reduces the computation of the instability index to a finite-dimensional space of trigonometric polyn

St. Raetz, M. Mugrauer, T. O. B. Schmidt, T. Roell

We report on observations of transit events of the transiting planets XO-1b and TrES-1 with a 25 cm telescope of the University Observatory Jena. With the transit timings for XO-1b from all 50 available XO, SuperWASP, Transit Light Curve (TLC)-Project- and Exoplanet Transit Database (ETD)-data, including our own I-band photometry obtained in March 2007, we f

F. F. Wilson

I report on recent measurements from the Belle and BaBar collaborations on the decay of the B-meson to hadronic final states without a charm quark.

Frederic Lechenault, Karen E. Daniels

Understanding granular and other athermal systems requires the identification of state variables which consistently predict their bulk properties. A promising approach has been to draw on the techniques of equilibrium statistical mechanics, but to consider alternate conserved quantities in place of energy. The Edwards ensemble, based on volume conservation,

Taha Sochi

In this article we report the release of a new program for batch processing and visualization of powder diffraction data. The program, which is free-of-charge for non-commercial use and can be obtained with its detailed documentation from our website www.scienceware.net, is currently in use by a number of researchers in University College London, University

Juan A. Bonachela, Miguel A. Munoz

We study two different types of systems with many absorbing states (with and without a conservation law) and scrutinize the effect of walls/boundaries (either absorbing or reflecting) into them. In some cases, non-trivial structured absorbing configurations (characterized by a background field) develop around the wall. We study such structures using a mean-f

S. K. Gorny, C. Chiappini, G. Stasinska, F. Cuisinier

We present a homogeneous set of spectroscopic measurements secured with 4-meter class telescopes for a sample of 90 planetary nebulae (PNe) located in the direction of the Galactic bulge. We derive their plasma parameters and chemical abundances. For half of the objects this is done for the first time. We discuss the accuracy of these data and compare it wit

Eduardo Esteves, Patricia Nogueira

Let C be a projective Gorenstein curve over an algebraically closed field of characteristic 0. A generalized linear system on C is a pair (I,f) consisting of a torsion-free, rank-1 sheaf I on C and a map of vector spaces f to the space of global sections of I. If the system is nondegenerate on every irreducible component of C, we associate to it a 0-cycle W,

Thierry Barbot, Francesco Bonsante, Jean-Marc Schlenker

We investigate 3-dimensional globally hyperbolic AdS manifolds containing "particles", i.e., cone singularities along a graph $Γ$. We impose physically relevant conditions on the cone singularities, e.g. positivity of mass (angle less than $2π$ on time-like singular segments). We construct examples of such manifolds, describe the cone singularities t

C Morgan, M Baxendale

We report the electrical responses of thin and thick single-walled carbon nanotube (SWNT) networks to N2 and O2 adsorption. In the surface desorbed state exposure to N2 and O2 provide an increase in conductance of thin and thick SWNT networks. The increase in conductance of both thin and thick networks is of a greater magnitude during O2 exposure rather than

Velleda Baldoni, Nicole Berline, Michèle Vergne

This document is a companion for the Maple program \textbf{Summing a polynomial function over integral points of a polygon}. It contains two parts. First, we see what this programs does. In the second part, we briefly recall the mathematical background.

J. Danon, Yu. V. Nazarov

We study electron transport in a double quantum dot in the Pauli spin blockade regime, in the presence of strong spin-orbit coupling. The effect of spin-orbit coupling is incorporated into a modified interdot tunnel coupling. We elucidate the role of the external magnetic field, the nuclear fields in the dots, and spin relaxation. We find qualitative agreeme

J. Vijande, A. Valcarce

In this letter we present a solution to describe simultaneously the light isoscalar and isovector vector mesons in constituent quark models. In Ref. [1] the $q\bar q$ spectrum was studied in a generalized constituent quark model constrained by the $NN$ phenomenology and the baryon spectrum. An overall good fit to the available experimental data was obtained.

S. Masson, K. -L. Klein, R. Buetikofer, E. Flueckiger

The origin of relativistic solar protons during large flare/CME events has not been uniquely identified so far.We perform a detailed comparative analysis of the time profiles of relativistic protons detected by the worldwide network of neutron monitors at Earth with electromagnetic signatures of particle acceleration in the solar corona during the large part

M. Consoli, L. Pappalardo

In the data of the ether-drift experiments there might be sizable fluctuations superposed on the smooth sinusoidal modulations due to the Earth's rotation and orbital revolution. These fluctuations might reflect the stochastic nature of the underlying "quantum ether" and produce vanishing averages for all vectorial quantities extracted from a nai

Larisza D. Krista, Peter T. Gallagher

We identify coronal holes using a histogram-based intensity thresholding technique and compare their properties to fast solar wind streams at three different points in the heliosphere. The thresholding technique was tested on EUV and X-ray images obtained using instruments onboard STEREO, SOHO and Hinode. The full-disk images were transformed into Lambert eq

T. Dudok de Wit, J. Watermann

The Sun provides the main energy input to the terrestrial atmosphere, and yet the impact of solar variability on long-term changes remains a controversial issue. Direct radiative forcing is the most studied mechanism. Other much weaker mechanisms, however, can have a significant leverage, but the underlying physics is often poorly known. We review the main m

T. Dudok de Wit, M. Kretzschmar, J. Lilensten, T. Woods

Solar UV emission has a profound impact on the upper terrestrial atmosphere. Because of instrumental constraints, however, solar proxies often need to be used as substitutes for the solar spectral variability. Finding proxies that properly reproduce specific spectral bands or lines is an ongoing problem. Using daily observations from 2003 to 2008 and a multi

R. Neuhaeuser, A. Koeltzsch, St. Raetz, T. O. B. Schmidt

We report new photometric observations of the 200000 year old naked weak-line run-away T Tauri star Par 1724, located north of the Trapezium cluster in Orion. We observed in the broad band filters B, V, R, and I using the 90cm Dutch telescope on La Silla, the 80cm Wendelstein telescope, and a 25cm telescope of the University Observatory Jena in Grossschwabha

Florian Freistetter, Áron Süli, Barbara Funk

The TrES-2 system harbors one planet which was discovered with the transit technique. In this work we investigate the dynamical behavior of possible additional, lower-mass planets. We identify the regions where such planets can move on stable orbits and show how they depend on the initial eccentricity and inclination. We find, that there are stable regions i

Moira I. Dolz, Alejandro B. Kolton, Hernan Pastoriza

We study finite-size effects at the onset of the irreversible magnetic behaviour of micron-sized Bi$_2$Sr$_2$CaCu$_2$O$_{8+δ}$ single crystals by using silicon micro-oscillators. We find an irreversibility line appearing well below the thermodynamic Bragg-glass melting line at a magnetic field which increases both with increasing the sample radius and with d

Maria Chiara Brambilla, Daniele Faenzi

By the description due to Mukai and Iliev, a smooth prime Fano threefold X of genus 9 is associated to a surface P(V), ruled over a smooth plane quartic Gamma. We use Kuznetsov's integral functor to study rank-2 stable sheaves on X with odd determinant. For each c_2 \geq 7, we prove that a component of their moduli space M_X(2,1,c_2) is birational to a B

Ritabrata Biswas, Subenoy Chakraborty

In the present work we study (i) charged black hole in Einstein-Gauss-Bonnet (EGB) theory, known as Einstein-Maxwell-Gauss-Bonnet (EMGB) black hole and (ii) black hole in EGB gravity with Yang-Mills field. The thermodynamic geometry of these two black hole solutions has been investigated, using the modified entropy in Gauss-Bonnet theory.

Luigi Corgnier

Mathematical proofs are presented concerning the existence of solutions of the Maxwell equations with suitable boundary conditions. In particular it is stated that the well known "delayed potentials" provide effective solutions of the equations, under reasonable conditions on the sources of the fields.

Jane H. Sheeba, V. K. Chandrasekar, M. Lakshmanan

We have identified the existence of globally clustered chimera states in delay coupled oscillator populations and find that these states can breathe periodically, aperiodically and become unstable depending upon the value of coupling delay. We also find that the coupling delay induces frequency suppression in the desynchronized group. We provide numerical ev

Dagfinn F. Vatne

We describe the endomorphism rings of maximal rigid objects in the cluster categories of tubes. Moreover, we show that they are gentle and have Gorenstein dimension 1. We analyse their representation theory and prove that they are of finite type. Finally, we study the relationship between the module category and the cluster tube via the Hom-functor.

Luo-Luo Jiang, Ming Zhao, Han-Xin Yang, Joseph Wakeling

In this paper, the total payoff of each agent is regulated to reduce the heterogeneity of the distribution of the total payoffs. It is found there is an optimal regulation strength where the fraction of cooperation is prominently promoted, too weak or too strong of the strength will have little effects or result in the disappearance of the cooperators. It is

Anindita Banerjee, Anirban Pathak

It is shown that the fault testing for quantum circuits does not follow conventional classical techniques. If probabilistic gate like Hadamard gate is included in a circuit then the classical notion of test vector is shown to fail. We have reported several new and distinguishing features of quantum fault and also presented a general methodology for detection

Helge Krueger

A variant of multiscale analysis for ergodic Schrödinger operators is developed. This enables us to prove positivity of Lyapunov exponents given initial scale estimates and an initial Wegner estimate. This is then applied to high dimensional skew-shifts at small coupling, where initial conditions are checked using the Pastur--Figotin formalism. Furthermore,

Wu Nan, Xuan Zuxing

This paper is devoted to investigate the singular directions of mero- morphic functions in some angular domains. We will confirm the existence of Hayman T directions in some angular domains. This is a continuous work of Yang [Yang L., Borel directions of meromorphic functions in an angular domain, Science in China, Math. Series(I)(1979), 149-163.] and Zheng

S. Bravina, N. Morozovsky, E. Dogheche, D. Remiens

The results of the investigation of impact of pulse humidity changes on the parameters of dynamic current-voltage loops and charge-voltage loops, and also dynamic transient currents for Pt/LiNbO3-film/Pt:Ti/SiO2/Si and porous Si/Si structures are presented. The peculiarities of current-voltage loops and transient currents curves are characteristic for poling

Alain Cournier, Swan Dubois, Vincent Villain

A snap-stabilizing algorithm ensures that it always behaves according to its specifications whenever it starts from an arbitrary configuration. In this paper, we interest in the message forwarding problem in a message-switched network. We must manage network ressources in order to deliver messages to any processor of the network. In this goal, we need inform

J. L. Liu, S. S. Zhang, Z. Cao, H. H. He

A tau lepton can be produced in a charged current interaction by cosmic ray tau neutrino with material inside a mountain. If it escapes from the mountain, it will decay and initiate a shower in the air, which can be detected by an air shower fluorescence/Cherenkov light detector. Designed according to such a principle, the Cosmic Ray Tau Neutrino Telescope (

Sakie Suzuki

A bottom tangle is a tangle in a cube consisting of arc components whose boundary points are on a line in the bottom square of the cube. A ribbon bottom tangle is a bottom tangle whose closure is a ribbon link. For every n-component ribbon bottom tangle T, we prove that the universal invariant J_T of T associated to the quantized enveloping algebra U_h(sl_2)

S. M. Gusein-Zade, I. Luengo, A. Melle Hernandez

In previous papers the authors gave formulae for generating series of classes (in the Grothendieck ring of complex quasi-projective varieties) of Hilbert schemes of zero-dimensional subschemes on smooth varieties and on orbifolds in terms of certain local data and the, so called, power structure over the corresponding ring. Here we give an analogue of these

Salah A. Aly, Ahmed E. Kamal

Link and node failures are common two fundamental problems that affect operational networks. Hence, protection of communication networks is essential to increase their reliability, performance, and operations. Much research work has been done to protect against link and node failures, and to provide reliable solutions based on pre-defined provision or dynami

Ritabrata Biswas, Subenoy Chakraborty

This paper deals with five-dimensional black hole solutions in (a) Einstein-Yang-Mills-Gauss-Bonnet theory and (b)Einstein-Maxwell-Gauss-Bonnet theory with a cosmological constant for spherically symmetric space time. The geometry of the black hole thermodynamics has been studied for both the black holes.

O. Ronsin, C. Caroli, T. Baumberger

We show that the aging of the mechanical relaxation of a gelatin gel exhibits the same scaling phenomenology as polymer and colloidal glasses. Besides, gelatin is known to exhibit logarithmic structural aging (stiffening). We find that stress accelerates this process. However, this effect is definitely irreducible to a mere age shift with respect to natural

Yong Zhang, Sun Kwok, Jun-ichi Nakashima

We present the results of a molecular line survey of the extreme carbon star CRL 3068. The observations were carried out with the Arizona Radio Observatory (ARO) 12m telescope and the Heinrich Hertz Submillimeter Telescope (SMT) at the 2mm and 1.3mm atmospheric windows. The observations cover the frequency bands from 130--162 GHz and 219.5--267.5 GHz. The ty

B. S. Wang, P. Tong, Y. P. Sun, X. Luo

We report the observation of large magnetocaloric effect near room temperature in antipervoskite SnCMn3. The maximal magnetic entropy change at the first-order ferrimagnetic-paramagnetic transition temperature (TC 279 K) is about 80.69mJ/cm3 K and 133mJ/cm3 K under the magnetic field of 20 kOe and 48 kOe, respectively. These values are close to those of typi

Mustafa Kulenovic, Orlando Merino

Let $T$ be a competitive map on a rectangular region $\mathcal{R}\subset \mathbb{R}^2$, and assume $T$ is $C^1$ in a neighborhood of a fixed point $\bar{\rm x}\in \mathcal{R}$. The main results of this paper give conditions on $T$ that guarantee the existence of an invariant curve emanating from $\bar{\rm x}$ when both eigenvalues of the Jacobian of $T$ at $

B. Vollmer

Based on a comparison of dynamical models with observations of the interstellar gas in 6 Virgo cluster spiral galaxies a first complete ram pressure stripping time sequence has been established. The observational characteristics of the different stages of ram pressure stripping are presented. The dynamical models yield the 3D velocity vectors of the galaxies

Pabitra Pal Choudhury, Sudhakar Sahoo, Sk Sarif Hasssan, Satrajit Basu

This paper presents a classification of Cellular Automata rules based on its properties at the nth iteration. Elaborate computer program has been designed to get the nth iteration for arbitrary 1-D or 2-D CA rules. Studies indicate that the figures at some particular iteration might be helpful for some specific application. The hardware circuit implementatio

L Assoud, F Ebert, P Keim, R Messina

We examine binary mixtures of superparamagnetic colloidal particles confined to a two-dimensional water-air interface both by real-space experiments and Monte-Carlo computer simulations at high coupling strength. In the simulations, the interaction is modelled as a pairwise dipole-dipole repulsion. While the ratio of magnetic dipole moments is fixed, the int

Roby Cherian, Priya Mahadevan, Clas Persson

Mn doping in dilute III-V alloys has been examined as a route to enhance ferromagnetic stability. Strong valence band bowing is expected at the dilute limit, implying a strong modification of the ferromagnetic stability upon alloying, with even an increase in some cases. Using first principle electronic structure calculations we show that while codoping with

R. N. Karasev

We consider billiard trajectories in a smooth convex body in $\mathbb R^d$ and estimate the number of distinct periodic trajectories that make exactly $p$ reflections per period at the boundary of the body. In the case of prime $p$ we obtain the lower bound $(d-2)(p-1)+2$, which is much better than the previous estimates.

Lei Zhao

For a type I basic classical Lie superalgebra $\mathfrak{g}=\mathfrak{g}_{\bar{0}} \oplus \mathfrak{g}_{\bar{1}}$, we establish an equivalence between typical blocks of categories of $U_χ(\mathfrak{g})$-modules and $U_χ(mathfrak{g}_{\bar{0})$-modules. We then deduce various consequences from the equivalence.

Tomohide Terasoma

In this paper, we proved that the F_p completioin of fundamental group of an F_p shceme can be computed by the bar complex of Artien-Schreier differential graded algebra. Artin-Schreier differential graded algebra is obtained by a relation diagram of identity map and frobenius map by Kats' theorem.

Prasun Dutta, Ayesha Begum, Somnath Bharadwaj, Jayaram N. Chengalur

We estimate the power spectrum of HI intensity fluctuations for a sample of 8 galaxies (7 dwarf and one spiral). The power spectrum can be fitted to a power law P_HI(U) = A U^αfor 6 of these galaxies, indicating turbulence is operational. The estimated best fit value for the slope ranges from ~ -1.5 (AND IV, NGC 628, UGC 4459 and GR 8) to ~ -2.6 (DDO 210 and

Raymond Chi-Wing Wong, Ada Wai-Chee Fu, Ke Wang, Yabo Xu

Group based anonymization is the most widely studied approach for privacy preserving data publishing. This includes k-anonymity, l-diversity, and t-closeness, to name a few. The goal of this paper is to raise a fundamental issue on the privacy exposure of the current group based approach. This has been overlooked in the past. The group based anonymization ap

Takahiro Tsushima

The Grothendieck-Ogg-Shafarevich formula calculates the l-adic Euler-Poincare number of an l-adic sheaf on a curve by an invariant produced by the wild ramification of the l-adic sheaf named Swan class. A. Abbes, K. Kato and T. Saito generalize this formula to any dimensional scheme. In this paper, assuming the strong resolution of singularities we prove a l

Robert J. Ducharme

The quantum constraint equations for a relativistic three-dimensional harmonic oscillator are shown to find concise expression in terms of Lorentz covariant ladder operators. These ladder operators consist of two conjugate 4-vectors that are each constrained to generate three linearly independent combinations of ladder operator components for raising and low

J. G. Robertson, J. Davis, M. J. Ireland, P. G. Tuthill

The University of Sydney has a long history in optical stellar interferometry. The first project, in the 1960s, was the Narrabri Stellar Intensity Interferometer, which measured the angular diameters of 32 hot stars and established the temperature scale for spectral classes O - F. That instrument was followed by the Sydney University Stellar Interferometer (

Lara B. Anderson, James Gray, Andre Lukas, Burt Ovrut

We study the sub-structure of the heterotic Kahler moduli space due to the presence of non-Abelian internal gauge fields from the perspective of the four-dimensional effective theory. Internal gauge fields can be supersymmetric in some regions of the Kahler moduli space but break supersymmetry in others. In the context of the four-dimensional theory, we inve

Chin-Fei Lee, Naomi Hirano, Aina Palau, Paul T. P. Ho

HH 211 is a nearby young protostellar system with a highly collimated jet. We have mapped it in 352 GHz continuum, SiO (J=8-7), and HCO+ (J=4-3) emission at up to ~ 0.2" resolution with the Submillimeter Array (SMA). The continuum source is now resolved into two sources, SMM1 and SMM2, with a separation of ~ 84 AU. SMM1 is seen at the center of the jet,

Tiangao Gou, Syed A. Jafar

The N+1 user, 1 x N single input multiple output (SIMO) Gaussian interference channel where each transmitter has a single antenna and each receiver has N antennas is studied. The symmetric capacity within O(1) is characterized for the symmetric case where all direct links have the same signal-to-noise ratio (SNR) and all undesired links have the same interfe

Fahad Saeed, Ashfaq Khokhar

Multiple Sequences Alignment (MSA) of biological sequences is a fundamental problem in computational biology due to its critical significance in wide ranging applications including haplotype reconstruction, sequence homology, phylogenetic analysis, and prediction of evolutionary origins. The MSA problem is considered NP-hard and known heuristics for the prob

M. Kawashima

In this paper, we compute the fundamental group of the complement of linear torus curves of maximal contact and we show that it is isomorphic that of generic linear torus curves.

Fang Wu, Dennis M. Wilkinson, Bernardo A. Huberman

A significant percentage of online content is now published and consumed via the mechanism of crowdsourcing. While any user can contribute to these forums, a disproportionately large percentage of the content is submitted by very active and devoted users, whose continuing participation is key to the sites' success. As we show, people's propensity to

Hitoshi Murayama, Jing Shu

Kibble mechanism drastically underestimates the production of topological defects, as confirmed recently in atomic and condensed matter systems. If non-thermally produced, they can be cosmological dark matter of mass 1-10 PeV. If thermalized, skyrmion of mass 1-10 TeV is also a viable dark matter candidate, whose decay may explain $e^\pm$ spectra in cosmic r

Kfir Blum, Cédric Delaunay, Yonit Hochberg

We study the stability of the Higgs potential in the framework of the effective Lagrangian beyond the MSSM. While the leading nonrenormalizable operators can shift the Higgs boson mass above the experimental bound, they also tend to render the scalar potential unbounded from below. The destabilization is correlated with the Higgs mass increase, so that if qu

J. S. Bagla, Abraham Loeb

We explore the prospects of using the hyperfine transition of 3He+ as a probe of the intergalactic medium. The emission signal from ionized regions during reionization is expected to be anti-correlated with 21cm maps. The predicted emission signal from Lyman-alpha blobs at lower redshifts is detectable with future radio observatories.

Stephen F. King, Christoph Luhn

We argue that the projective special linear group PSL(2,7), also known as Sigma(168), has unique features which make it the most suitable discrete family symmetry for describing quark and lepton masses and mixing in the framework of SO(10) type unified models. In such models flavon fields in the sextet representation of PSL(2,7) play a crucial role both in o

Predrag R. Jelenkovic, Mariana Olvera-Cravioto

We study the situations when the solution to a weighted stochastic recursion has a power law tail. To this end, we develop two complementary approaches, the first one extends Goldie's (1991) implicit renewal theorem to cover recursions on trees; and the second one is based on a direct sample path large deviations analysis of weighted recursive random sum

Xiangyun Fu, Puxun Wu, Hongwei Yu

We study the linear growth of matter perturbations in the DGP model with the growth index $γ$ as a function of redshift. At the linear approximation: $γ(z)\approxγ_0+γ_0^\prime z $, we find that, for $0.2\leqΩ_{m,0}\leq0.35$, $γ_0$ takes the value from 0.658 to 0.671, and $γ_0^\prime$ ranges from 0.035 to 0.042. With three low redshift observational data of

Parker E. Lowrey

We begin by discussing various ways autoequivalences and stability conditions associated to triangulated categories can interact. Once an appropriate definition of compatibility is formulated, we derive a sufficiency criterion for this compatibility. We next apply this criterion to derived categories associated to Galois covers of the Weierstrass nodal cubic

Efrain J. Ferrer, Vivian de la Incera

In this paper we investigate the non-perturbative generation of an anomalous magnetic moment for massless fermions in the presence of an external magnetic field. In the context of massless QED in a magnetic field, we prove that the phenomenon of magnetic catalysis of chiral symmetry breaking, which has been associated in the literature with dynamical mass ge

Roland Vergnioux

We study existence, uniqueness and triviality of path cocycles in the quantum Cayley graph of universal discrete quantum groups. In the orthogonal case we find that the unique path cocycle is trivial, in contrast with the case of free groups where it is proper. In the unitary case it is neither bounded nor proper. From this geometrical result we deduce the v

Kentaro Nagamine

We examine the past and current work on the star formation (SF) histories of dwarf galaxies in cosmological hydrodynamic simulations. The results obtained from different numerical methods are still somewhat mixed, but the differences are understandable if we consider the numerical and resolution effects. It remains a challenge to simulate the episodic nature

Piotr W. Klamut, Tomasz Plackowski, Marcin Matusiak

The temperature dependencies of the resistivity for the superconducting ruthenocuprates of nominal compositions RuSr2GdCu2O8, Ru0.98Sr2GdCu2O8 and Ru0.5Sr2GdCu2.5O8-d were examined for the magnetic field dependent characteristics of the superconducting transitions. The effect of the insignificant diminishing of the Ru/Cu ratio in parent RuSr2GdCu2O8 was conf

D. H. Correa, C. A. S. Young

We identify the leading finite-size (Luscher-type) correction to the energy of open strings ending on maximal giant gravitons. In particular we obtain the leading finite size correction at weak 't Hooft coupling and in the planar limit to the energy of very short vacuum states. These results are shown to agree with certain 1, 2, 3 and 4-loop dual gauge t

Tsz Yan Lam, Ravi K. Sheth

We show how the excursion set moving barrier model for halo abundances may be generalized to the local non-Gaussian f_{nl} model. Our estimate assumes that the distribution of step sizes depends on f_{nl}, but that they are otherwise uncorrelated. Our analysis is consistent with previous results for the case of a constant barrier, and highlights some implici

M. G. Kozlov

$Λ$-doublet spectra of light diatomic radicals have high sensitivity to the possible variations of the fine structure constant alpha and electron-to-proton mass ratio beta. For molecules OH and CH sensitivity is further enhanced because of the J-dependent decoupling of the electron spin from the molecular axis, where J is total angular momentum of the molecu

Tsz Yan Lam, Ravi K. Sheth, Vincent Desjacques

We generalize Doroshkevich's celebrated formulae for the eigenvalues of the initial shear field associated with Gaussian statistics to the local non-Gaussian f_{nl} model. This is possible because, to at least second order in f_{nl}, distributions at fixed overdensity are unchanged from the case f_{nl}=0. We use this generalization to estimate the effect

Xuesong Li, Weiwei Cai, Jinho An, Seyoung Kim

Graphene has been attracting great interest because of its distinctive band structure and physical properties. Today, graphene is limited to small sizes because it is produced mostly by exfoliating graphite. We grew large-area graphene films of the order of centimeters on copper substrates by chemical vapor deposition using methane. The films are predominant

Gia Dvali, Michele Redi

We postulate an exact permutation symmetry acting on 10^32 Standard Model copies as the largest possible symmetry extension of the Standard Model. This setup automatically lowers the fundamental gravity cutoff down to TeV, and thus, accounts for the quantum stability of the weak scale. We study the phenomenology of this framework and show that below TeV ener

Hui Zhai, Fa Wang, Dung-Hai Lee

The iron pnictides and the cuprates represent two families of materials, where strong antiferromagnetic correlation drives three other distinct ordering tendencies: (1) superconducting pairing, (2) Fermi surface distortion, and (3) orbital current order. We propose that (1)-(3) and the antiferromagnetic correlation are the hallmarks of a class of strongly co

V. S. Shchesnovich

It is shown that for a $N$-boson system the parity of $N$ can be responsible for a qualitative difference in the system response to variation of a parameter. The nonlinear boson model is considered, which describes tunneling of boson pairs between two distinct modes $X_{1,2}$ of the same energy and applies to a Bose-Einstein condensate in an optical lattice.

P. Forn-Diaz, R. N. Schouten, W. A. den Braver, J. E. Mooij

We fabricated and tested a squelch circuit consisting of a copper powder filter with an embedded Josephson junction connected to ground. For small signals (squelch-ON), the small junction inductance attenuates strongly from DC to at least 1 GHz, while for higher frequencies dissipation in the copper powder increases the attenuation exponentially with frequen

Weicheng Lv, Jiansheng Wu, Philip Phillips

We attribute the structural phase transition (SPT) in the parent compounds of the iron pnictides to orbital ordering. Due to the anisotropy of the $d_{xz}$ and $d_{yz}$ orbitals in the $xy$ plane, a ferro-orbital ordering makes the orthorhombic structure more energetically favorable, thus inducing the SPT. In this orbital-ordered system, the sites with orbit

Cheng-Wei Qiu, Andrey Novitsky, Hua Ma, Shaobo Qu

An analytical method of electromagnetic wave interactions with a general radially anisotropic cloak is established. It is able to deal with arbitrary parameters ($ε_r(r)$, $μ_r(r)$, $ε_t(r)$ and $μ_t(r)$) of a radially anisotropic inhomogeneous shell. The general cloaking condition is proposed from the wave relations for the first time. We derive the paramet