arXiv papers from September 2011

Nikodem J. Poplawski

We derive a relation between the two polarization modes of a plane, linear gravitational wave in the second-order approximation. Since these two polarizations are not independent, an initially monochromatic gravitational wave loses its periodic character due to the nonlinearity of the Einstein field equations. Accordingly, real gravitational waves may differ

C. Slezak, K. M. Koenig, R. J. Endorf, G. A. Braun

This paper examines the educational impact of the implementation of "Changes in Energy and Momentum" from the Tutorials in Introductory Physics in five different instructional settings. These settings include (1) a completely computer-based learning environment and (2) use of cooperative learning groups with varying levels of instructor support. Pre- and pos

Yongyao Li, Boris A. Malomed, Jianxiong Wu, Wei Pang

We study large-amplitude one-dimensional solitary waves in photonic crystals featuring competition between linear and nonlinear lattices, with minima of the linear potential coinciding with maxima of the nonlinear pseudopotential, and vice versa (inverted nonlinear photonic crystals, INPhCs), in the case of the saturable self-focusing nonlinearity. Such crys

Niharika Ranjan

The angular distributions of Upsilon(1S) to mu+ mu- decays are analyzed using a sample of Upsilon(1S) mesons in 2.9 fb^{-1} of data collected at sqrt{s} = 1.96TeV. The results of the one-dimensional angular analysis suggest that Upsilon(1S) may be longitudinal polarized at high transverse momentum. This observation is largely inconsistent with NRQCD predicti

Elizabeth Rivers, Alex Markowitz, Richard Rothschild

We have analyzed 16 months of sustained monitoring observations of Cen A from the Rossi X-ray Timing Explorer to search for changes in the absorbing column in the line of sight to the central nucleus. We present time-resolved spectroscopy which indicates that a discrete clump of material transited the line of sight to the central illuminating source over the

Kotaro Tsugawa

We prove the local well-posedness for the Cauchy problem of the Korteweg-de Vries equation in a quasi periodic function space. The function space contains functions such that f=f_1+f_2+...+f_N where f_j is in the Sobolev space of order s>-1/2N of a_j periodic functions. Note that f is not a periodic function when the ratio of periods a_i/a_j is irrational. T

Takayoshi Katase, Soshi Iimura, Hidenori Hiramatsu, Toshio Kamiya

Electron doping of a 122-type iron pnictide BaFe2As2 by substituting the Ba site with an aliovalent ion (indirect doping), which had been unsuccessful by conventional solid-state synthesis methods, was achieved by a non-equilibrium film growth process. The substitution with La was substantiated by a systematic shrinkage of the c-axis lattice parameter due to

V. Ziegler

We present studies in bottomonium spectroscopy carried out with samples of $(98\pm1)$ million $\Upsilon(2S)$ and $(121\pm1)$ million $\Upsilon(3S)$ events recorded with the BaBar detector at the PEP-II asymmetric-energy $e^+ e^-$ collider at SLAC. Precise measurements of the branching fractions for $\chi_{b1,2}(1P, 2P)\rightarrow \gamma \Upsilon(1S)$ and $\c

Wensong Wu, Edsel A. Peña

This paper deals with the problem of simultaneously making many (M) binary decisions based on one realization of a random data matrix X. M is typically large and X will usually have M rows associated with each of the M decisions to make, but for each row the data may be low dimensional. A Bayesian decision-theoretic approach for this problem is implemented w

Chanwoo Kim, Seok-Bae Yun

In rotationally symmetric domains, the Boltzmann equation with specular reflection boundary condition has a special type of equilibrium states called the rotational local Maxwellian which, unlike the uniform Maxwellian, has an additional term related to the angular momentum of the gas. In this paper, we consider the initial boundary value problem of the Bolt

Jerzy Matyjasek, Katarzyna Zwierzchowska

The perturbative solutions to the semiclassical Einstein field equations describing spherically-symmetric and static lukewarm black hole are constructed. The source term is composed of the (classical) stress-energy tensor of the electromagnetic field and the renormalized stress-energy tensor of the quantized massive scalar field in a large mass limit. We use

Wystan Benbow

The VERITAS array of 12-m atmospheric-Cherenkov telescopes is used in an intensive observation program focused on the discovery of VHE (E > 100 GeV) gamma-ray-emitting blazars. Since VERITAS began full-scale operation in 2007, more than 1000 hours of observation, on ~90 targets, have been devoted to the VHE blazar discovery effort and to timely follow-up in

H. S. Kohler

The Busch-formula relates the energy-spectrum of two point-like particles interacting in a 3-D isotropic Harmonic Oscillator trap to the free scattering phase-shifts of the particles. This formula is used to find an expression for the \it shift \rm in the spectrum from the unperturbed (non-interacting) spectrum rather than the spectrum itself. This shift is

Wystan Benbow

The VERITAS array of 12-m atmospheric-Cherenkov telescopes in southern Arizona began full-scale operations in 2007, and it is one of the world's most sensitive detectors of astrophysical VHE (E > 100 GeV) gamma rays. Forty-one blazars are known to emit VHE photons, and observations of blazars are one of the VERITAS Collaboration's Key Science Projects (KSPs)

Henning Bruhn

We prove that every stability two unit disk graph has chromatic number at most 3/2 times its clique number.

Emilio Elizalde, Pedro J. Silva

Ho\v{r}ava-Lifshitz gravity is shown to exhibit a peculiar behavior, when scattering amplitudes are considered. At low energies it seems to classicalize i.e. the effective size of the interaction grows as a function of the $s$-parameter, with BHs forming part of the spectrum; but when the probing energy is increased such that higher order operators become im

Patrick Hennebelle, Gilles Chabrier

We present an analytical determination of the star formation rate (SFR) in molecular clouds, based on a time-dependent extension of our analytical theory of the stellar initial mass function (IMF). The theory yields SFR's in good agreement with observations, suggesting that turbulence {\it is} the dominant, initial process responsible for star formation. In

Charles L. Epstein, Rafe Mazzeo

We analyze a class of partial differential equations that arise as "backwards Kolmogorov operators" in infinite population limits of the Wright-Fisher models in population genetics and in mathematical finance. These are degenerate elliptic operators defined on manifolds with corners. The classical example is the Kimura diffusion operator, which acts on funct

Marco Cicalese, Emanuele Spadaro

We give a detailed description of the geometry of single droplet patterns in a nonlocal isoperimetric problem. In particular we focus on the sharp interface limit of the Ohta-Kawasaki free energy for diblock copolymers, regarded as a paradigm for those energies modeling physical systems characterized by a competition between short and a long-range interactio

Saman Gharib, Kalle Karu

CORRECTION. One of the main results in this paper contains a fatal error. We cannot conclude the existence of nontrivial vector bundles on X from the nontriviality of its K-group. The K-group that is computed here is the Grothendieck group of perfect complexes and not vector bundles. Since the varieties are not quasi-projective, existence of nontrivial perfe

M. Surdeanu, L. Marquez, X. Carreras, P. R. Comas

This paper introduces and analyzes a battery of inference models for the problem of semantic role labeling: one based on constraint satisfaction, and several strategies that model the inference as a meta-learning problem using discriminative classifiers. These classifiers are developed with a rich set of novel features that encode proposition and sentence-le

C. Guestrin, M. Hauskrecht, B. Kveton

Efficient representations and solutions for large decision problems with continuous and discrete variables are among the most important challenges faced by the designers of automated decision support systems. In this paper, we describe a novel hybrid factored Markov decision process (MDP) model that allows for a compact representation of these problems, and

J. Pineau, G. Gordon, S. Thrun

The Partially Observable Markov Decision Process has long been recognized as a rich framework for real-world planning and control problems, especially in robotics. However exact solutions in this framework are typically computationally intractable for all but the smallest problems. A well-known technique for speeding up POMDP solving involves performing valu

B. Faltings, P. Pu, P. Viappiani

We consider interactive tools that help users search for their most preferred item in a large collection of options. In particular, we examine example-critiquing, a technique for enabling users to incrementally construct preference models by critiquing example options that are presented to them. We present novel techniques for improving the example-critiquin

N. Nisan, A. Ronen

A major achievement of mechanism design theory is a general method for the construction of truthful mechanisms called VCG (Vickrey, Clarke, Groves). When applying this method to complex problems such as combinatorial auctions, a difficulty arises: VCG mechanisms are required to compute optimal outcomes and are, therefore, computationally infeasible. However,

S. F. Smith, M. J. Streeter

We characterize the search landscape of random instances of the job shop scheduling problem (JSP). Specifically, we investigate how the expected values of (1) backbone size, (2) distance between near-optimal schedules, and (3) makespan of random schedules vary as a function of the job to machine ratio (N/M). For the limiting cases N/M approaches 0 and N/M ap

L. Liu, M. Truszczynski

We study properties of programs with monotone and convex constraints. We extend to these formalisms concepts and results from normal logic programming. They include the notions of strong and uniform equivalence with their characterizations, tight programs and Fages Lemma, program completion and loop formulas. Our results provide an abstract account of proper

Alessandro Mirizzi, Pasquale D. Serpico

The usual description of self-induced flavor conversions for neutrinos (\nu's) in supernovae is based on the simplified assumption that all the \nu's of the different species are emitted "half-isotropically" by a common neutrinosphere, in analogy to a blackbody emission. However, realistic supernova simulations show that \nu angular distributions at decoupli

Sven Apel, Hendrik Speidel, Philipp Wendler, Alexander von Rhein

A software product line is a set of software products that are distinguished in terms of features (i.e., end-user--visible units of behavior). Feature interactions ---situations in which the combination of features leads to emergent and possibly critical behavior--- are a major source of failures in software product lines. We explore how feature-aware verifi

Ö. Yılmaz, A. C. C. Say

It was recently proved that a sound and complete qualitative simulator does not exist, that is, as long as the input-output vocabulary of the state-of-the-art QSIM algorithm is used, there will always be input models which cause any simulator with a coverage guarantee to make spurious predictions in its output. In this paper, we examine whether a meaningfull

Sumin Tang, Jonathan Grindlay, Maxwell Moe, Jerome Orosz

We present photometric and spectroscopic observations of a peculiar variable (designated DASCH J075731.1+201735 or J0757) discovered from our DASCH project using the digitized Harvard College Observatory archival photographic plates. It brightened by about 1.5 magnitudes in B within a year starting in 1942, and then slowly faded back to its pre-outburst brig

Oleg N. Kirillov

With perfectly balanced gain and loss, dynamical systems with indefinite damping can obey the exact PT-symmetry being marginally stable with a pure imaginary spectrum. At an exceptional point where the symmetry is spontaneously broken, the stability is lost via passing through a non-semisimple 1:1 resonance. In the parameter space of a general dissipative sy

Gongjie Li, Charlie Conroy, Abraham Loeb

We investigate the evolution of the MBH-{\sigma} relation by examining the relationship between the intrinsic scatter in the MBH-{\sigma} relation and galaxy bolometric nuclear luminosity, the latter being a probe of the accretion rate of the black hole (BH). Our sample is composed of galaxies with classical bulges when possible, of which 38 have dynamically

S. Bethke, A. H. Hoang, S. Kluth, J. Schieck

These are the proceedings of the "Workshop on Precision Measurements of alphas" held at the Max-Planck-Institute for Physics, Munich, February 9-11, 2011. The workshop explored in depth the determination of alphas(mZ) in the MS-bar scheme from the key categories where high precision measurements are currently being made, including DIS and global PDF fits, ta

Jounghun Lee, Marco Baldi

It has been recently shown that the observed morphological properties of the Bullet Cluster can be accurately reproduced in hydrodynamical simulations only when the infall pairwise velocity V_{c} of the system exceeds 3000km/s (or at least possibly 2500 km/s) at the pair separation of 2R_{vir}, where R_{vir} is the virial radius of the main cluster, and that

Motoi Endo, Sho Iwamoto

The dijet signature at the LHC is studied in new physics models for the top forward-backward asymmetry at the Tevatron. In the t-mediator models, flavor-changing interactions contribute to the dijet production cross section as well as the asymmetry at least at the one-loop level. It is found that the LHC dijet measurements at 36pb^(-1) have constrained the Z

M. E. Putman, D. R. Saul, E. Mets

A head-tail high-velocity cloud (HVC) is a neutral hydrogen halo cloud that appears to be interacting with the diffuse halo medium as evident by its compressed head trailed by a relatively diffuse tail. This paper presents a sample of 116 head-tail HVCs across the southern sky (d < 2 deg) from the HI Parkes All Sky Survey (HIPASS) HVC catalog, which has a sp

Michael Smy

Super-Kamiokande is sensitive to neutrino interactions between 4 and 100MeV via elastic scattering and inverse beta decay. I will present Super-Kamiokande's ongoing measurements of solar neutrinos and its searches for supernova neutrinos.

Aleksandra Foltynowicz, Ticijana Ban, Piotr Maslowski, Florian Adler

We achieve a quantum-noise-limited absorption sensitivity of 1.7/times10$^{-12}$ cm$^{-1}$ per spectral element at 400 s of acquisition time with cavity-enhanced frequency comb spectroscopy, the highest demonstrated for a comb-based technique. The system comprises a frequency comb locked to a high-finesse cavity and a fast-scanning Fourier transform spectrom

John D. Jakeman, Stephen G. Roberts

In this paper we present a locally and dimension-adaptive sparse grid method for interpolation and integration of high-dimensional functions with discontinuities. The proposed algorithm combines the strengths of the generalised sparse grid algorithm and hierarchical surplus-guided local adaptivity. A high-degree basis is used to obtain a high-order method wh

Louigi Addario Berry, Colin McDiarmid, Bruce Reed

A class A of labelled graphs is bridge-addable if for all graphs G in A and all vertices u and v in distinct connected components of G, the graph obtained by adding an edge between u and u is also in A; the class A is monotone if for all G in A and all subgraphs H of G, H is also in A. We show that for any bridge-addable, monotone class A whose elements have

L. Trouille, A. J. Barger, C. Tremonti

The Baldwin, Phillips, and Terlevich emission-line ratio diagnostic ([OIII]/H{\beta} versus [NII]/H{\alpha}, hereafter BPT diagram) efficiently separates galaxies whose signal is dominated by star formation <BPT-SF> from those dominated by AGN activity (BPT-AGN). Yet this BPT diagram is limited to z < 0.5, the redshift at which [NII]{\lambda}6584 leaves the

Johanna Erdmenger, Patrick Kerner, Hansjörg Zeller

We study transport phenomena in p-wave superfluids in the context of gauge/gravity duality. Due to the spacetime anisotropy of this system, the tensorial structure of the transport coefficients is non-trivial in contrast to the isotropic case. In particular, there is an additional shear mode which leads to a non-universal value of the shear viscosity even in

Dan Hooper, Tim Linden

The region surrounding the center of the Milky Way is both astrophysically rich and complex, and is predicted to contain very high densities of dark matter. Utilizing three years of data from the Fermi Gamma Ray Space Telescope (and the recently available Pass 7 ultraclean event class), we study the morphology and spectrum of the gamma ray emission from this

James E. Geach

We present an application of unsupervised machine learning - the self-organised map (SOM) - as a tool for visualising, exploring and mining the catalogues of large astronomical surveys. Self-organisation culminates in a low-resolution representation of the 'topology' of a parameter volume, and this can be exploited in various ways pertinent to astronomy. Usi

Andrew Hornig, Christopher Lee, Jonathan R. Walsh, Saba Zuberi

We derive the leading non-global logarithms (NGLs) of ratios of jet masses m_{1,2} and a jet energy veto \Lambda due to soft gluons splitting into regions in and out of jets. Such NGLs appear in any exclusive jet cross section with multiple jet measurements or with a veto imposed on additional jets. Here, we consider back-to-back jets of radius R produced in

James C. Green, Cynthia S. Froning, Steve Osterman, Dennis Ebbets

The Cosmic Origins Spectrograph (COS) is a moderate-resolution spectrograph with unprecedented sensitivity that was installed into the Hubble Space Telescope (HST) in May 2009, during HST Servicing Mission 4 (STS-125). We present the design philosophy and summarize the key characteristics of the instrument that will be of interest to potential observers. For

Asher Auel, Marcello Bernardara, Michele Bolognesi

Let X -> Y be a fibration whose fibers are complete intersections of two quadrics. We develop new categorical and algebraic tools---a theory of relative homological projective duality and the Morita invariance of the even Clifford algebra under quadric reduction by hyperbolic splitting---to study semiorthogonal decompositions of the bounded derived category

Chi-kwan Chan, Dhrubaditya Mitra, Axel Brandenburg

In two-dimensional forced Navier-Stokes turbulence, energy cascades to the largest scales in the system to form a pair of coherent vortices known as the Bose condensate. We show, both numerically and analytically, that the energy condensation saturates and the system reaches a statistically stationary state. The time scale of saturation is inversely proporti

Sophie Zhang

We study the directional dependence of the angular two-point correlation function in maps of the cosmic microwave background (CMB). We propose two new statistics, one which measures the correlation of each point in the sky with a ring of points separated angle theta away, and a second that measures the missing angular correlation above 60 degrees as a functi

M. Klintenberg, O. Eriksson

We report here the completion of the electronic structure of the majority of the known stoichiometric inorganic compounds, as listed in the International Crystal Structure Data-base (ICSD). We make a detailed comparison of the electronic structure, crystal geometry and chemical bonding of cuprate high temperature superconductors, with the calculated over six

Álvaro Gómez-León, Gloria Platero

We investigate electron localization and dynamical spin locking induced by ac magnetic fields in double quantum dots. We demonstrate that by tuning the ac magnetic fields parameters, i.e., the field intensity, frequency, and the phase difference between the fields within each dot, coherent destruction of tunneling (and thus charge localization) can be achiev

E. Diehl

The ATLAS muon spectrometer is designed to measure muon momenta with a resolution of 4% @ 100 GeV/c rising to 10% @ 1 TeV/c track momentum. The spectrometer consists of precision tracking and trigger chambers embedded in a 2T magnetic field generated by three large air-core superconducting toroids. The precision detectors provide 50 micron tracking resolutio

Noel D'Souza, Jayasimha Atulasimha, Supriyo Bandyopadhyay

A circular magnetic disk with biaxial magnetocrystalline anisotropy has four stable magnetization states which can be used to encode a pixel's shade in a black/gray/white image. By solving the Landau-Lifshitz- Gilbert equation, we show that if moderate noise deflects the magnetization slightly from a stable state, it always returns to the original state, the

M. Mihalkovic, C. L. Henley

By fitting to a database of ab-initio forces and energies, we can extract pair potentials for alloys, with a simple six-parameter analytic form including Friedel oscillations, which give a remarkably faithful account of many complex intermetallic compounds. Furthermore, such potentials are combined with a method of discovering complex zero-temperature struct

Peng Wang, Houwen Wu, Haitang Yang

In this letter, we propose that the recent measurement of superluminal neutrinos in OPERA could be explained by the existence of a domain wall which is left behind after the phase transition of some scalar field in the universe. The scalar field couples to the neutrino and photon field with different effective couplings. It causes different effective metrics

J. E. Padilha, Matheus P. Lima, A. J. R. da Silva, A. Fazzio

We study the electronic transport properties of a dual-gated bilayer graphene nanodevice via first principles calculations. We investigate the electric current as a function of gate length and temperature. Under the action of an external electrical field we show that even for gate lengths up 100 Ang., a non zero current is exhibited. The results can be expla

R. Michael Barnett

There are many varied programs of education and outreach in particle physics. This report for the Division of Particles and Fields of the American Physical Society 2001 meeting reviews the impact of these programs in general, and also gives several examples of ongoing programs with a primary focus on those in the US.

G. Redlinger

This is a brief and limited review of searches for physics beyond the Standard Model from the ATLAS, CDF, CMS and D0 experiments, as of the end of July 2011. Priority is given to the most recent results and to those with the largest integrated luminosity analyzed.

Dirk Beyer, Thomas A. Henzinger, M. Erkan Keremoglu, Philipp Wendler

Software model checking, as an undecidable problem, has three possible outcomes: (1) the program satisfies the specification, (2) the program does not satisfy the specification, and (3) the model checker fails. The third outcome usually manifests itself in a space-out, time-out, or one component of the verification tool giving up; in all of these failing cas

C. P. J. Adolphs, P. Berenbrink

In this paper we consider neighborhood load balancing in the context of selfish clients. We assume that a network of n processors and m tasks is given. The processors may have different speeds and the tasks may have different weights. Every task is controlled by a selfish user. The objective of the user is to allocate his/her task to a processor with minimum

Simone S. Alexandre, A. D. Lucio, A. H. Castro Neto, R. W. Nunes

Ab initio calculations indicate that while the electronic states introduced by grain boundaries in graphene are only partially confined to the defect core, a domain boundary introduces states near the Fermi level that are very strongly confined to the core of the defect, and that display a ferromagnetic ground state. The domain boundary is fully immersed wit

David Pérez-Suárez, Paul A. Higgins, D. Shaun Bloomfield, R. T. James McAteer

The solar surface and atmosphere are highly dynamic plasma environments, which evolve over a wide range of temporal and spatial scales. Large-scale eruptions, such as coronal mass ejections, can be accelerated to millions of kilometres per hour in a matter of minutes, making their automated detection and characterisation challenging. Additionally, there are

David A. Buote, Philip J. Humphrey

This is the first of two papers investigating the deprojection and spherical averaging of ellipsoidal galaxy clusters. We specifically consider applications to hydrostatic X-ray and Sunyaev-Zel'dovich (SZ) studies, though many of the results also apply to isotropic dispersion-supported stellar dynamical systems. Here we present analytical formulas for galaxy

A. Farhoodfar, R. J. Gooding, W. A. Atkinson

We have studied the effects of interactions on persistent currents in half-filled and quarter-filled Hubbard models with weak and intermediate strength disorder. Calculations are performed using a variational Gutzwiller ansatz that describes short range correlations near the Mott transition. We apply an Aharonov-Bohm magnetic flux, which generates a persiste

Marek Korkusinski, Oleksandr Voznyy, Pawel Hawrylak

We present a theory of highly excited interacting carriers confined in a semiconductor nanostructure, incorporating Auger coupling between excited states with different number of excitations. The Coulomb matrix elements connecting exciton, bi-exciton and tri-exciton complexes are derived and an intuitive picture of breaking neutral multi-exction complexes in

Pramod Dominic, Prasanta K. Tripathy

In this paper we examine the stability of non-supersymmetric attractors in type IIA supergravity compactified on a Calabi-Yau manifold, in the presence of sub-leading corrections to the N=$ pre-potential. We study black hole configurations carrying D0-D6 and D0-D4 charges. We consider the O(1) corrections to the pre-potential given by the Euler number of the

M. Larouche, F. W. Lemire, J. Patera

In the paper we present a new, uniform and comprehensive description of centralizers of the maximal regular subgroups in compact simple Lie groups of all types and ranks. The centralizer is either a direct product of finite cyclic groups, a continuous group of rank 1, or a product, not necessarily direct, of a continuous group of rank 1 with a finite cyclic

Jolanta Borysiuk, Jakub Sołtys, Rafal Bożek, Jacek Piechota

Principal structural defects in graphene layers, synthesized on a carbon-terminated face, i.e. the SiC(000) face of a 4H-SiC substrate, are investigated using microscopic methods. Results of high-resolution transmission electron microscopy (HRTEM) reveal their atomic arrangement. Mechanism of such defects creation, directly related to the underlying crystall

Zhiwei Yang

The LHC timing signals are broadcast to various destinations in the subsequent experiments. And all of them could be delayed to time in the ATLAS sub-detectors by using the Corde board and the RF2TTC module. The ATLAS BPTX detectors and monitoring system could guarantee the demanded sychronization of the beam in the futher collision.

Filippo Del Tedesco, Sebastian Hunt, David Sands

We consider the problem of logical data erasure, contrasting with physical erasure in the same way that end-to-end information flow control contrasts with access control. We present a semantic hierarchy for erasure policies, using a possibilistic knowledge-based semantics to define policy satisfaction such that there is an intuitively clear upper bound on wh

E. Aguayo, J. E. Fast, E. W. Hoppe, M. E. Keillor

A brief review of the history and neutrino physics of double beta decay is given. A description of the MAJORANA DEMONSTRATOR research and development program including background reduction techniques is presented in some detail. The application of point contact (PC) detectors to the experiment is discussed, including the effectiveness of pulse shape analysis

B. K. Mani, Dilip Angom

We examine the contributions from triple excitation cluster operators in the relativistic coupled-cluster theory in atoms and ions. For this, we propose a tensor representation of the triple cluster operator. Based on this representaion and using diagrammatic analysis, we derive the linearized coupled-cluster equations for single, double and triple excitatio

W. Pan, N. Masuhara, N. S. Sullivan, K. W. Baldwin

We compare the energy gap of the \nu=5/2 fractional quantum Hall effect state obtained in conventional high mobility modulation doped quantum well samples with those obtained in high quality GaAs transistors (heterojunction insulated gate field-effect transistors). We are able to identify the different roles that long range and short range disorders play in

Adrien Allain, Zheng Han, Vincent Bouchiat

Graphene is a sturdy and chemically inert material exhibiting an exposed two-dimensional electron gas of high mobility. These combined properties enable the design of graphene composites either based on covalent or non- covalent coupling of adsorbates, or on multilayered structures. These systems have exhibited novel tunable electronic properties such as ban

Sebastıan Martınez Bustos, Jorgen Vitting Andersen, Michel Miniconi, Andrzej Nowak

Human decision making by professionals trading daily in the stock market can be a daunting task. It includes decisions on whether to keep on investing or to exit a market subject to huge price swings, and how to price in news or rumors attributed to a specific stock. The question then arises how professional traders, who specialize in daily buying and sellin

Gilberto Bini, Fabio Felici, Margarida Melo, Filippo Viviani

We investigate GIT quotients of polarized curves. More specifically, we study the GIT problem for the Hilbert and Chow schemes of curves of degree d and genus g in a projective space of dimension d-g, as the ratio v:=d/(2g-2) decreases. We prove that the first three values of v at which the GIT quotients change are given by v=4, 3.5, 2. We show that, for v>4

J. Ristein, S. Mammadov, Th. Seyller

We explain the robust p-type doping observed for quasi-free standing graphene on hexagonal silicon carbide by the spontaneous polarization of the substrate. This mechanism is based on a bulk property of SiC, unavoidable for any hexagonal polytype of the material and independent of any details of the interface formation. We show that sign and magnitude of the

Jens D. Baltrusch, Cecilia Cormick, Gabriele De Chiara, Tommaso Calarco

A procedure is discussed for creating coherent superpositions of motional states of ion strings. The motional states are across the structural transition linear-zigzag, and their coherent superposition is achieved by means of spin-dependent forces, such that a coherent superposition of the electronic states of one ion evolves into an entangled state between

N. D. Richardson, D. R. Gies, N. D. Morrison, G. Schaefer

We report on the preliminary results of a three-year monitoring campaign of Galactic and Magellanic LBVs with both moderate and high resolution spectroscopy. We have collected more than 500 moderate-resolution spectra of 20 stars in the red portion of the optical spectrum, which includes the wind-sensitive transitions of H$\alpha$ and He I 5876 and 6678 Angs

Florian Preis, Anton Rebhan, Andreas Schmitt

We discuss the effect of baryonic matter on the zero-temperature chiral phase transition at finite chemical potential in the presence of a background magnetic field. The main part of our study is done in the deconfined geometry of the Sakai-Sugimoto model, i.e., at large N_c and strong coupling, with non-antipodal separation of the flavor branes. We find tha

Srijeeta Talukder, Pinaki Chaudhury, Ralf Metzler, Suman K Banik

We suggest that the thermodynamic stability parameters (nearest neighbor stacking and hydrogen bonding free energies) of double-stranded DNA molecules can be inferred reliably from time series of the size fluctuations (breathing) of local denaturation zones (bubbles). On the basis of the reconstructed bubble size distribution, this is achieved through stocha

James D. Aldous, Christopher W. Burrows, Ana M. Sánchez, Richard Beanland

Epitaxial films including bulk-like cubic and wurtzite polymorphs of MnSb have been grown by molecular beam epitaxy on GaAs via careful control of the Sb4/Mn flux ratio. Nonzero-temperature density functional theory was used to predict ab initio the spin polarization as a function of reduced magnetization for the half-metals NiMnSb and cubic MnSb. In both ca

J. Alimena

We report on a search for charged massive long-lived particles (CMLLPs), based on 5.2 fb$^{-1}$ of data collected with the D0 detector at the Fermilab Tevatron $p\bar{p}$ collider. CMLLPs are predicted in many theories of physics beyond the standard model. We look for events in which one or more particles are reconstructed as muons but have speed and ionizat

Mario S. Cardaci, Paolo Cea, Leonardo Cosmai, Rossella Falcone

We analyze the distribution of the chromoelectric field generated by a static quark-antiquark pair in the SU(3) vacuum. We find that the transverse profile of the flux tube resembles the dual version of the Abrikosov vortex field distribution and give an estimate of the London penetration length in the confined vacuum.

E. H. El Abdalaoui, A. Messaoudi

We extend the Killeen-Taylor study in \cite{KT} by investigating in different Banach spaces ($\ell^\alpha(\N), c_0(\N),c_c(\N)$) the point, continuous and residual spectra of stochastic perturbations of the shift operator associated to the stochastic adding machine in base 2 and in Fibonacci base. For the base 2, the spectra are connected to the Julia set of

J. Flipse, F. L. Bakker, A. Slachter, F. K. Dejene

The Peltier coefficient describes the amount of heat that is carried by an electrical current when it passes through a material. Connecting two materials with different Peltier coefficients causes a net heat flow towards or away from the interface, resulting in cooling or heating at the interface - the Peltier effect. Spintronics describes the transport of c

V. I. Klyukhin, D. Campi, B. Curé, A. Gaddi

Flux loops have been installed on selected segments of the magnetic flux return yoke of the 4 T superconducting coil of the Compact Muon Solenoid (CMS) detector under construction at CERN. Voltages induced in the loops during discharge of the solenoid will be sampled online during the entire discharge and integrated offline to provide a measurement of the in

E. F. Keane, M. A. McLaughlin, .

Over the past several years, it has become apparent that some radio pulsars demonstrate significant variability in their single pulse amplitude distributions. The Rotating Radio Transients (RRATs), pulsars discovered through their single, isolated pulses, are one of the more extreme manifestations of this variability. Nearly 70 of these objects have been fou

L. J. Salazar, D. A. Guzmán, F. J. Rodríguez, L. Quiroga

The dependence of the excitonic two-photon absorption on the quantum correlations (entanglement) of exciting biphotons by a semiconductor quantum well is studied. We show that entangled photon absorption can display very unusual features depending on space-time-polarization biphoton parameters and absorber density of states for both bound exciton states as w

S. Khoroshkin, O. Ogievetsky

We establish the absence of zero divisors in the reduction algebra of a Lie algebra g with respect to its reductive Lie sub-algebra k. The class of reduction algebras include the Lie algebras (they arise when k is trivial) and the Gelfand--Kirillov conjecture extends naturally to the reduction algebras. We formulate the conjecture for the diagonal reduction

Julianne J. Dalcanton, Benjamin F. Williams, Jason L. Melbourne, Léo Girardi

We present near-infrared (NIR) color-magnitude diagrams (CMDs) for the resolved stellar populations within 26 fields of 23 nearby galaxies (<4 Mpc), based on F110W and F160W images from Wide Field Camera 3 (WFC3) on the Hubble Space Telescope (HST). The CMDs sample both old dormant and young star-forming populations. We match key NIR CMD features with their

I. Pillitteri, H. M. Guenther, S. J. Wolk, V. Kashyap

We report on the follow-up XMM-Newton observation of the planet-hosting star HD 189733 we obtained in April 2011. We observe a flare just after the secondary transit of the hot Jupiter. This event shares the same phase and many of the characteristics of the flare we observed in 2009. We suggest that a systematic interaction between planet and stellar magneti

N. Jafari, A. Shariati

A class of projective actions of the orthogonal group on the projective space is being studied. It is shown that the Fock--Lorentz, and Magueijo--Smolin transformations known as Doubly Special Relativity are such transformations. The formalism easily lead to new type transformations.

R. Narayanan

Large N gauge theories with adjoint matter can be numerically studied using lattice techniques. Eguchi-Kawai reductions holds for this theory and one can reduce the lattice model to a single site. Hybrid Monte Carlo algorithm can be used to simulate this model. One can either perform an exact computation of the "fermionic force" or use pseudo fermions as par

M. Reshetnyak, D. Sokoloff

Fluctuations of the alpha-effect which break equatorial symmetry of the flow in the kinematic Parker's dynamo are considered. We show, that even small (a few percents) fluctuation can leed to the substantial assymmetry of the magnetic field in the hemispheres as well as the propagation of the dynamo wave through the equator plane. We also consider how change

P. Petit, F. Lignières, G. A. Wade, M. Aurière

We present the result of a highly sensitive spectropolarimetric study dedicated to intermediate mass stars. We report the detection of sub-gauss surface magnetic fields on the normal, rapidly-rotating A-type star Vega and on the moderately-rotating Am star Sirius A. These magnetic detections constitute the first evidence that tepid stars that do not belong t

Easwar Magesan, Jay M. Gambetta, Joseph Emerson

We describe and expand upon the scalable randomized benchmarking protocol proposed in Phys. Rev. Lett. 106, 180504 (2011) which provides a method for benchmarking quantum gates and estimating the gate-dependence of the noise. The protocol allows the noise to have weak time and gate-dependence, and we provide a sufficient condition for the applicability of th

Amit Goyal, Francesco Bonchi, Laks V. S. Lakshmanan

Influence maximization is the problem of finding a set of users in a social network, such that by targeting this set, one maximizes the expected spread of influence in the network. Most of the literature on this topic has focused exclusively on the social graph, overlooking historical data, i.e., traces of past action propagations. In this paper, we study in

Jens Krueger, Changkyu Kim, Martin Grund, Nadathur Satish

Read-optimized columnar databases use differential updates to handle writes by maintaining a separate write-optimized delta partition which is periodically merged with the read-optimized and compressed main partition. This merge process introduces significant overheads and unacceptable downtimes in update intensive systems, aspiring to combine transactional