Research archive

arXiv papers from July 2012

The most recent 100 records published that month. Open any paper for its original abstract, citation metadata, related research, and reading tools.

  1. Friedwardt Winterberg

    A deuterium-tritium (DT) nuclear pulse propulsion concept for fast interplanetary transport is proposed utilizing almost all the energy for thrust and without the need for a large radiator: 1. By letting the thermonuclear micro-explosion take place in the center of a liquid hydrogen sphere with the radius of the sphere large enough to slow down and absorb th

  2. Alicia Lopez, Alice Rogers

    Extending phase space to include time and it canonical conjugate energy as well as the usual momentum and position variables, and then introducing the constraint which sets energy equal to the Hamiltonian, gives a symplectic action of the additive group R which corresponds to time translation along the solutions to the equations of motion. This allows the BR

  3. Sutanay Choudhury, Lawrence Holder, George Chin, John Feo

    Graph pattern matching involves finding exact or approximate matches for a query subgraph in a larger graph. It has been studied extensively and has strong applications in domains such as computer vision, computational biology, social networks, security and finance. The problem of exact graph pattern matching is often described in terms of subgraph isomorphi

  4. JunZe Han, Xiang-Yang Li

    For mobile devices, communication via cellular networks consumes more energy, and has a lower data rate than WiFi networks, and suffers an expensive limited data plan. However the WiFi network coverage range and density are smaller than those of the cellular networks. In this work, we present a behavior-aware and preference-based approach to prefetch news we

  5. Micha Sharir, Adam Sheffer, Joshua Zahl

    We establish an improved upper bound for the number of incidences between m points and n circles in three dimensions. The previous best known bound, originally established for the planar case and later extended to any dimension $\ge 2$, is $O*(m^{2/3}n^{2/3} + m^{6/11}n^{9/11}+m+n)$, where the $O*(\cdot)$ notation hides sub-polynomial factors. Since all the

  6. Yuanyue Liu, Xiaolong Zou, Boris I. Yakobson

    A new dislocation structure-square-octagon pair (4|8) is discovered in two-dimensional boron nitride (h-BN), via first-principles calculations. It has lower energy than corresponding pentagon-heptagon pairs (5|7), which contain unfavorable homo-elemental bonds. Based on the structures of dislocations, grain boundaries (GB) in BN are investigated. Depending o

  7. P. D. T. A. Elliott, Jonathan Kish

    A method of estimating sums of multiplicative functions braided with Dirichlet characters is demonstrated, leading to a taxonomy of the characters for which such sums are large.

  8. Rolando Dünner, Matthew Hasselfield, Tobias A. Marriage, Jon Sievers

    We present a description of the data reduction and mapmaking pipeline used for the 2008 observing season of the Atacama Cosmology Telescope (ACT). The data presented here at 148 GHz represent 12% of the 90 TB collected by ACT from 2007 to 2010. In 2008 we observed for 136 days, producing a total of 1423 hours of data (11 TB for the 148 GHz band only), with a

  9. Maria Grazia Pia, Georg Weidenspointner

    Monte Carlo simulation is an essential component of experimental particle physics in all the phases of its life-cycle: the investigation of the physics reach of detector concepts, the design of facilities and detectors, the development and optimization of data reconstruction software, the data analysis for the production of physics results. This note briefly

  10. M. Zeppenfeld, B. G. U. Englert, R. Glöckner, A. Prehn

    The rich internal structure and long-range dipole-dipole interactions establish polar molecules as unique instruments for quantum-controlled applications and fundamental investigations. Their potential fully unfolds at ultracold temperatures, where a plethora of effects is predicted in many-body physics, quantum information science, ultracold chemistry, and

  11. Florian Dörfler, Michael Chertkov, Francesco Bullo

    The emergence of synchronization in a network of coupled oscillators is a fascinating topic in various scientific disciplines. A coupled oscillator network is characterized by a population of heterogeneous oscillators and a graph describing the interaction among them. It is known that a strongly coupled and sufficiently homogeneous network synchronizes, but

  12. Tina Lund, Annop Wongwathanarat, Hans-Thomas Janka, Ewald Müller

    We study supernova neutrino flux variations in the IceCube detector, using 3D models based on a simplified neutrino transport scheme. The hemispherically integrated neutrino emission shows significantly smaller variations compared with our previous study of 2D models, largely because of the reduced SASI activity in this set of 3D models which we interpret as

  13. Kyle Lawson

    If the dark matter of our galaxy is composed of nuggets of quarks or antiquarks in a colour superconducting phase there will be a small but non-zero flux of these objects through the Earth's atmosphere. A nugget of quark matter will deposit only a small fraction of its kinetic energy in the atmosphere and is unlikely to be detectable. If however the impactin

  14. Robert Raussendorf, Tzu-Chieh Wei

    Quantum computation is a novel way of information processing which allows, for certain classes of problems, exponential speedups over classical computation. Various models of quantum computation exist, such as the adiabatic, circuit and measurement-based models. They have been proven equivalent in their computational power, but operate very differently. As s

  15. C. R. Gwinn, M. D. Johnson, J. E. Reynolds, D. L. Jauncey

    We present measurements of the linear diameter of the emission region of the Vela pulsar at observing wavelength lambda=18 cm. We infer the diameter as a function of pulse phase from the distribution of visibility on the Mopra-Tidbinbilla baseline. As we demonstrate, in the presence of strong scintillation, finite size of the emission region produces a chara

  16. C. R. Gwinn, M. D. Johnson, J. E. Reynolds, D. L. Jauncey

    We compare the noise in interferometric measurements of the Vela pulsar from ground- and space-based antennas with theoretical predictions. The noise depends on both the flux density and the interferometric phase of the source. Because the Vela pulsar is bright and scintillating, these comparisons extend into both the low and high signal-to-noise regimes. Fu

  17. Olaf Hohm, Alasdair Routh, Paul K. Townsend, Baocheng Zhang

    We present a "Chern-Simons-like" action for the "general massive gravity" model propagating two spin-2 modes with independent masses in three spacetime dimensions (3D), and we use it to find a simple Hamiltonian form of this model. The number of local degrees of freedom, determined by the dimension of the physical phase space, agrees with a linearized analys

  18. Carlos A. Jimenez-Hoyos, R. Rodriguez-Guzman, Gustavo E. Scuseria

    Mean-field methods such as Hartree-Fock (HF) or Hartree-Fock-Bogoliubov (HFB) constitute the building blocks upon which more elaborate many-body theories are based on. The HF and HFB wavefunctions are built out of independent quasi-particles resulting from a unitary linear canonical transformation of the elementary fermion operators. Here, we discuss the pos

  19. Yukio Tomozawa

    The author has suggested that the knee phenomenon in the cosmic ray energy spectrum at 3 PeV can be explained as a split between a radiation-dominated expansion and a matter-dominated expansion of an expanding heat bath. The model proposed in 1985, in fact, predicted that high energy cosmic rays are emitted from AGN, massive black holes, in agreement with re

  20. Salvatore Greco, Fabio Rindone

    In decision analysis and especially in multiple criteria decision analysis, several non additive integrals have been introduced in the last years. Among them, we remember the Choquet integral, the Shilkret integral and the Sugeno integral. In the context of multiple criteria decision analysis, these integrals are used to aggregate the evaluations of possible

  21. Kyoungchul Kong

    This note summarizes a pedagogical tutorial on CalcHEP and PYTHIA that was given at TASI 2011 program.

  22. Lee A. Rozema, Ardavan Darabi, Dylan H. Mahler, Alex Hayat

    While there is a rigorously proven relationship about uncertainties intrinsic to any quantum system, often referred to as "Heisenberg's Uncertainty Principle," Heisenberg originally formulated his ideas in terms of a relationship between the precision of a measurement and the disturbance it must create. Although this latter relationship is not rigorously pro

  23. Camilo Delgado-Correal, José E. García

    By using the satelital information of Earth observation unloaded by a station constructed in the country and reflectances measurements of the soil, we found the total radiation attenuation of the atmosphere for a small region of the Colombian territory. It was necessary to use the Fourier's theory that describes the ideal filters of signals to find the trans

  24. Gary Steigman

    According to the standard models of particle physics and cosmology, there should be a background of cosmic neutrinos in the present Universe, similar to the cosmic microwave photon background. The weakness of the weak interactions renders this neutrino background undetectable with current technology. The cosmic neutrino background can, however, be probed ind

  25. Andreas Nink, Martin Reuter

    We identify a simple physical mechanism which is at the heart of Asymptotic Safety in Quantum Einstein Gravity (QEG) according to all available effective average action-based investigations. Upon linearization the gravitational field equations give rise to an inverse propagator for metric fluctuations comprising two pieces: a covariant Laplacian and a curvat

  26. Lance J. Nelson, Fei Zhou, Gus L. W. Hart, Vidvuds Ozolins

    The widely-accepted intuition that the important properties of solids are determined by a few key variables underpins many methods in physics. Though this reductionist paradigm is applicable in many physical problems, its utility can be limited because the intuition for identifying the key variables often does not exist or is difficult to develop. Machine le

  27. Tobias Reichenbach, Aleksandra Stefanovic, Fumiaki Nin, A. J. Hudspeth

    Sound is detected and converted into electrical signals within the ear. The cochlea not only acts as a passive detector of sound, however, but can also produce tones itself. These otoacoustic emissions are a striking manifestation of the cochlea's mechanical active process. A controversy remains of how these mechanical signals propagate back to the middle ea

  28. Eric Marchand, William E. Strawderman

    For estimating a lower bounded parametric function in the framework of Marchand and Strawderman (2006), we provide through a unified approach a class of Bayesian confidence intervals with credibility $1-\alpha$ and frequentist coverage probability bounded below by $\frac{1-\alpha}{1+\alpha}$. In cases where the underlying pivotal distribution is symmetric, t

  29. Pavan Hosur

    Weyl semimetals harbor unusual surface states known as Fermi arcs, which are essentially disjoint segments of a two dimensional Fermi surface. We describe a prescription for obtaining Fermi arcs of arbitrary shape and connectivity by stacking alternate two dimensional electron and hole Fermi surfaces and adding suitable interlayer coupling. Using this prescr

  30. Amir H. Rezaeian

    The forthcoming LHC measurements in proton-nucleus (pA) collisions at forward rapidities can discriminate between the color glass condensate (CGC) and alternative approaches including standard collinear factorization one. We report some of our recent predictions based on gluon saturation/CGC formalism for pA collisions at the LHC including the charged hadron

  31. Mark Dukes, Yvan Le Borgne

    We classify recurrent configurations of the sandpile model on the complete bipartite graph K_{m,n} in which one designated vertex is a sink. We present a bijection from these recurrent configurations to decorated parallelogram polyominoes whose bounding box is a m*n rectangle. Several special types of recurrent configurations and their properties via this bi

  32. Charles Ci Wen Lim, Christopher Portmann, Marco Tomamichel, Renato Renner

    Device-independent quantum key distribution (DIQKD) in its current design requires a violation of Bell's inequality between two honest parties, Alice and Bob, who are connected by a quantum channel. However, in reality, quantum channels are lossy, and this can be exploited for attacks based on the detection loophole. Here, we propose a novel approach to DIQK

  33. Kyle S. Dawson, David J. Schlegel, Christopher P. Ahn, Scott F. Anderson

    The Baryon Oscillation Spectroscopic Survey (BOSS) is designed to measure the scale of baryon acoustic oscillations (BAO) in the clustering of matter over a larger volume than the combined efforts of all previous spectroscopic surveys of large scale structure. BOSS uses 1.5 million luminous galaxies as faint as i=19.9 over 10,000 square degrees to measure BA

  34. Iftikhar Ahmad

    We investigate the analytical behavior of many scalar fields working collectively, where {\phi} i is the ith scalar field. Furthermore, we evaluate its parameter values by applying certain constraints on our model parameters, and then compare these values with current observational data from Observational data of CMB, BAO and H 0 . Through our results, we de

  35. David S. Berman, Edvard T. Musaev, Daniel C. Thompson

    We consider the reduction of the duality invariant approach to M-theory by a U-duality group valued Scherk-Schwarz twist. The result is to produce potentials for gauged supergravities that are normally associated with non-geometric compactifications. The local symmetry reduces to gauge transformations with the gaugings exactly matching those of the embedding

  36. L. Basso, K. Mimasu, S. Moretti

    In the attempt to fully profile a $Z'$ boson accessible at the Large Hadron Collider (LHC), we study the sensitivity of di-lepton (for the electron, muon and tauon cases) and di-quark (for the case of the heavy flavours, $t$ and, possibly, $b$) samples to the nature of the new gauge state, for a one-dimensional class of non-exotic $Z'$ bosons. Assuming reali

  37. M. P. M. Dean, R. S. Springell, C. Monney, K. J. Zhou

    The dynamics of S=1/2 quantum spins on a 2D square lattice lie at the heart of the mystery of the cuprates \cite{Hayden2004,Vignolle2007,Li2010,LeTacon2011,Coldea2001,Headings2010,Braicovich2010}. In bulk cuprates such as \LCO{}, the presence of a weak interlayer coupling stabilizes 3D N\'{e}el order up to high temperatures. In a truly 2D system however, the

  38. Carmen Cortázar, Marta Garcia-Huidobro, Cecilia Yarur

    In this paper we establish the existence of bound state solutions of any given order to $$ \Delta_m u +f(u)=0, x\in R^N, N\ge m>1, (P) $$ where $\Delta_m u=\nabla\cdot(|\nabla u|^{m-2}\nabla u)$ using the same techniques as in [GST] to establish the existence of a ground state solution to (P). Since our solutions change sign, we assume f is continuous in R.

  39. Eugenio Bottacini, Marco Ajello, Jochen Greiner

    The super-massive black-holes in the centers of Active Galactic Nuclei (AGNs) are surrounded by obscuring matter that can block the nuclear radiation. Depending on the amount of blocked radiation, the flux from the AGN can be too faint to be detected by currently flying hard X-ray (above 15 keV) missions. At these energies only ~1% of the intensity of the Co

  40. Wade DeGottardi, Diptiman Sen, Smitha Vishveshwara

    We present a unified study of the effect of periodic, quasiperiodic and disordered potentials on topological phases that are characterized by Majorana end modes in 1D p-wave superconducting systems. We define a topological invariant derived from the equations of motion for Majorana modes and, as our first application, employ it to characterize the phase diag

  41. Astrid Eichhorn, Holger Gies, Dietrich Roscher

    We study the renormalization flow of axion electrodynamics, concentrating on the non-perturbative running of the axion-photon coupling and the mass of the axion (like) particle. Due to a non-renormalization property of the axion-photon vertex, the renormalization flow is controlled by photon and axion anomalous dimensions. As a consequence, momentum-independ

  42. Alessio Marrani, Cong-Xin Qiu, Sheng-Yu Darren Shih, Anthony Tagliaferro

    We present a novel gauge field theory, based on the Freudenthal Triple System (FTS), a ternary algebra with mixed symmetry (not completely symmetric) structure constants. The theory, named Freudenthal Gauge Theory (FGT), is invariant under two (off-shell) symmetries: the gauge Lie algebra constructed from the FTS triple product and a novel global non-polynom

  43. Tigran Kalaydzhyan

    In this paper we argue that the strongly coupled quark-gluon plasma can be considered as a chiral superfluid. The "normal" component of the fluid is the thermalized matter in common sense, while the "superfluid" part consists of long wavelength (chiral) fermionic states moving independently. We use several nonperturbative techniques to demonstrate that. Firs

  44. Richard J. Parker

    In this contribution I present a review of star formation in clusters. I begin by discussing the various definitions of what constitutes a star cluster, and then compare the outcome of star formation (IMF, multiplicity, mass segregation and structure and morphology) in different star-forming regions. I also review recent numerical models of star formation in

  45. Yang-Ting Chien, Randall Kelley, Matthew D. Schwartz, Hua Xing Zhu

    A method is developed for calculating the jet mass distribution at hadron colliders using an expansion about the kinematic threshold. In particular, we consider the mass distribution of jets of size R produced in association with a hard photon at the Large Hadron Collider. Expanding around the kinematic threshold, where all the energy goes into the jet and t

  46. Sean Tulin, Hai-Bo Yu, Kathryn M. Zurek

    Recently, there have been hints for dark matter (DM) annihilation in the galactic center to one or more photon lines. In order to achieve the observed photon line flux, DM must have a relatively large effective coupling to photons, typically generated radiatively from large couplings to charged particles. When kinematically accessible, direct annihilation of

  47. Xi Kang, Andrea V. Macciò, Aaron A. Dutton

    In this paper we combine high resolution N-body simulations with a semi analytical model of galaxy formation to study the effects of a possible Warm Dark Matter (WDM) component on the observable properties of galaxies. We compare three WDM models with a dark matter mass of 0.5, 0.75 and 2.0 keV, with the standard Cold Dark Matter case. For a fixed set of par

  48. Krzysztof Nalewajko, Mitchell C. Begelman

    We perform a local (short-wavelength) linear stability analysis of an axisymmetric column of magnetized plasma with a nearly toroidal magnetic field and a smooth poloidal velocity shear by perturbing the equations of relativistic magnetohydrodynamics. We identify two types of unstable modes, which we call 'exponential' and 'overstable', respectively. The exp

  49. Ido Reiss, Uri Keshet

    Tangential discontinuities, seen as X-ray edges known as cold fronts (CFs), are ubiquitous in cool-core galaxy clusters. We analyze all 17 deprojected CF thermal profiles found in the literature, including three new CFs we tentatively identify (in clusters A2204 and 2A0335). We discover small but significant thermal pressure drops below all nonmerger CFs, an

  50. Richard J. Parker, Thomas Maschberger, Catarina Alves de Oliveira

    We apply two different algorithms to search for mass segregation to a recent observational census of the rho Ophiuchi star forming region. Firstly, we apply the Lambda_MSR method, which compares the minimum spanning tree (MST) of a chosen subset of stars to MSTs of random subsets of stars in the cluster, and determine the mass segregation ratio, Lambda_MSR.

  51. M. A. Nowak, A. Paizis, J. Rodriguez, S. Chaty

    IGR J18179-1621 is an obscured accreting X-ray pulsar discovered by INTEGRAL on 2012 February 29. We report on our 20 ksec Chandra-High Energy Transmission Gratings Spectrometer observation of the source performed on 2012 March 17, on two short contemporaneous Swift observations, and on our two near-infrared (K_s, H_n, and J_n) observations performed on 2012

  52. Thomas Bilitewski, Ralph Schönrich

    We study the effects of radial flows on Galactic chemical evolution. A simple analytic scheme is developed prescribing the coupling of infall from the intergalactic medium and radial flows within the disc based on angular momentum conservation. We show that model parameters are tightly constrained by the observed [Fe/H]-abundance gradient in the Galactic dis

  53. G. Stinson, C. Brook, A. V. Macciò, J. Wadsley

    We introduce the Making Galaxies in a Cosmological Context (MaGICC) program of smoothed particle hydrodynamics (SPH) simulations. We describe a parameter study of galaxy formation simulations of an L* galaxy that uses early stellar feedback combined with supernova feedback to match the stellar mass--halo mass relationship. While supernova feedback alone can

  54. A. Iovan, M. Fischer, R. Lo Conte, V. Korenivski

    Colloidal lithography [1] is how patterns are reproduced in a variety of natural systems and is used more and more as an efficient fabrication tool in bio-, opto-, and nano-technology. Nanoparticles in the colloid are made to form a mask on a given material surface, which can then be transferred via etching into nano-structures of various sizes, shapes, and

  55. José R. Espinosa, Christophe Grojean, Verónica Sanz, Michael Trott

    We perform a global fit to Higgs signal-strength data in the context of light stops in Natural SUSY. In this case, the Wilson coefficients of the higher dimensional operators mediating g g -> h and h -> \gamma \gamma, given by c_g, c_\gamma, are related by c_g = 3 (1 + 3 \alpha_s/(2 \pi)) c_\gamma/8. We examine this predictive scenario in detail, combining H

  56. D. J. Summers, L. M. Cremaldi, A. Datta, M. Duraisamy

    A decade ago, a cost analysis was conducted to bore a 233 km circumference Very Large Hadron Collider (VLHC) tunnel passing through Fermilab. Here we outline implementations of $e^+e^-$, $p \bar{p}$, and $\mu^+ \mu^-$ collider rings in this tunnel using recent technological innovations. The 240 and 500 GeV $e^+e^-$ colliders employ Crab Waist Crossings, ultr

  57. Matthew Neal, Bernard Russo

    A necessary and sufficient condition for an operator space to support a multiplication making it completely isometric and isomorphic to a unital operator algebra is proved. The condition involves only the holomorphic structure of the Banach spaces underlying the operator space.

  58. Lupin C. C. Lin, Jumpei Takata, Albert K. H. Kong, C. Y. Hui

    We report on an 105 ks Suzaku observation of the supernova remnant CTA 1 (G119.5+10.2). The Suzaku soft X-ray observation was carried out with both timing mode and imaging mode. A ~ 10' extended feature, which is interpreted as a bow-shock component of the pulsar wind nebula (PWN), is revealed in this deep observation for the first time. The nebular spectrum

  59. Carlos P. Ortiz, Robert Riehn, Karen E. Daniels

    We observe the formation of heaps of repulsive microspheres, created by flowing a colloidal microsphere suspension towards a flat-topped ridge placed within a quasi two-dimensional microfluidic channel. This configuration allows for both shear and normal forces on the microspheres in contact with the ridge. The heaps, which form against the ridge, are charac

  60. Roman G. Smirnov, Amelia L. Yzaguirre

    We employ joint invariants of Killing two-tensors defined in the Euclidean plane to characterize the Smorodinsky-Winternitz potential and explain the geometric meaning of its arbitrary parameters. In addition, we verify for which values of the arbitrary parameter $k$ the Tremblay-Turbiner-Winternitz potential is multi-separable.

  61. James G. Puckett, Karen E. Daniels

    Although jammed granular systems are athermal, several thermodynamic-like descriptions have been proposed which make quantitative predictions about the distribution of volume and stress within a system and provide a corresponding temperature-like variable. We perform experiments with an apparatus designed to generate a large number of independent, jammed, tw

  62. Timothy R. Waters, Daniel Proga

    A simple 1D dynamical model of thermally driven disc winds is proposed, based on the results of recent, 2.5D axi-symmetric simulations. Our formulation of the disc wind problem is in the spirit of the original Parker (1958) and Bondi (1952) problems, namely we assume an elementary flow configuration consisting of an outflow following pre-defined trajectories

  63. Steven S. Y. Lu, De-Qi Zhang

    Let X be a complex projective variety and D a reduced divisor on X. Under a natural minimal condition on the singularities of the pair (X, D), which includes the case of smooth X with simple normal crossing D, we ask for geometric criteria guaranteeing various positivity conditions for the log-canonical divisor K_X+D. By adjunction and running the log minima

  64. Haimin Wang, Chang Liu

    Solar flare emissions in the chromosphere often appear as elongated ribbons on both sides of the magnetic polarity inversion line (PIL), which has been regarded as evidence of a typical configuration of magnetic reconnection. However, flares having a circular ribbon have rarely been reported, although it is expected in the fan--spine magnetic topology involv

  65. Ronnie Sebastian

    Voevodsky has conjectured that numerical and smash equivalence coincide on a smooth projective variety. We prove the conjecture for one dimensional cycles on an arbitrary product of curves. As a consequence we get that numerically trivial 1-cycles on an abelian variety are smash nilpotent.

  66. S. Van Loo, T. W. Hartquist, S. A. E. G. Falle

    Research performed in the 1950s and 1960s by Leon Mestel on the roles of magnetic fields in star formation established the framework within which he and other key figures have conducted subsequent investigations on the subject. This short tribute to Leon contains a brief summary of some, but not all, of his ground breaking contributions in the area. It also

  67. Wolfhard Hansen, Ivan Netuka

    A champagne subdomain of a connected open set $U\ne\emptyset$ in $R^d$, $d\ge 2$, is obtained omitting pairwise disjoint closed balls $\bar{B}(x,r_x)$, $x\in X$, the bubbles, where $X$ is an infinite, locally finite set in $U$. The union $A$ of these balls may be unavoidable, that is, Brownian motion, starting in $U\setminus A$ and killed when leaving $U$, m

  68. Zhong Wang, Binghai Yan

    We propose the concept of `topological Hamiltonian' for topological insulators and superconductors in interacting systems. The eigenvalues of topological Hamiltonian are significantly different from the physical energy spectra, but we show that topological Hamiltonian contains the information of gapless surface states, therefore it is an exact tool for topol

  69. David Viennot, José Lages

    We study a kind of geometric phases for entangled quantum systems, and particularly a spin driven by a magnetic field and entangled with another spin. The new kind of geometric phase is based on an analogy between open quantum systems and dissipative quantum systems which uses a C\ast-module structure. We show that the system presents from the viewpoint of t

  70. Pierre-Philippe Dechant

    In this paper, we show that via a novel construction every rank-3 root system induces a root system of rank 4. Via the Cartan-Dieudonn\'e theorem, an even number of successive Coxeter reflections yields rotations that in a Clifford algebra framework are described by spinors. In three dimensions these spinors themselves have a natural four-dimensional Euclide

  71. Alex Dugas

    Let T be a Hom-finite triangulated Krull-Schmidt category over a field k. Inspired by a definition of Koenig and Liu, we say that a family S of pairwise orthogonal objects in T with trivial endomorphism rings is a simple-minded system if its closure under extensions is all of T. We construct torsion pairs in T associated to any subset X of a simple-minded sy

  72. Larry R. Nittler, Eric Gaidos

    We review current observational and theoretical constraints on the Galactic chemical evolution (GCE) of oxygen isotopes in order to explore whether GCE plays a role in explaining the lower 17O/18O ratio of the Sun, relative to the present-day interstellar medium, or the existence of distinct 16O-rich and 16O-poor reservoirs in the Solar System. Although the

  73. Moez Daoulatli

    In this paper we study the behaviors of the energy of solutions of the wave equations with localized nonlinear damping in exterior domains.

  74. D. G. C. McKeon

    A non-Abelian gauge field with a topological action is coupled to a spin 3/2 Majorana spinor. The symmetries of this model are analyzed using the Dirac constraint formalism. These symmetries include a Fermionic symmetry and the algebra of these symmetries closes; it is not the algebra of supergravity. The action is invariant without the need to introduce aux

  75. Andrew Dougherty

    We report measurements for the initial stages of sidebranching during the dendritic growth of ammonium chloride from supersaturated aqueous solution. The earliest sidebranches are approximately periodic; they are first evident about $36 \rho$ behind the tip, where $\rho$ is the tip radius, and have an average initial spacing of about $5 \rho$, though both va

  76. Henry Arellano-P., J. Orlando Rangel-CH

    Two methods of exploratory spatial data analysis (ESDA), analysis of spatial heterogeneity and dependence (auto-correlation), - - were applied to the cover patterns from ten paramo localities in the Central and Eastern cordilleras of Colombia. Among the localities studied, the high montane region of the Serrania de Perija, the paramo region of the Los Nevado

  77. Adela Vásquez, Henry Arellano

    We estimated the aerial biomass and stored carbon in twelve types of forests in the department of C\'ordoba with annual rain fall ranging from 3000 mm (super humid climates) to 1300 mm (semi-humid climate). Biomass was estimated based on structural aspects of the vegetation (diameter at breast height, total height, and wood specific weight). We tested nine a

  78. Kwok-Kun Kwong

    In this paper, we obtain a positivity result of a quasi-local mass integral as proposed by Shi and Tam in general dimensions. The main argument is based on the monotonicity of a mass integral in a foliation of quasi-spherical metrics and a positive mass type theorem which was proved by Wang and Yau in the three dimensional case, and is shown here in higher d

  79. Colin Adams

    A triple crossing is a crossing in a projection of a knot or link that has three strands of the knot passing straight through it. A triple crossing projection is a projection such that all of the crossings are triple crossings. We prove that every knot and link has a triple crossing projection and then investigate c_3(K), which is the minimum number of tripl

  80. Hannu Holopainen, Pasi Huovinen

    In hydrodynamical modeling of the ultrarelativistic heavy-ion collisions the freeze-out is typically performed at a constant temperature or density. In this work we apply a dynamical freeze-out criterion, which compares the hydrodynamical expansion rate with the pion scattering rate. Recently many calculations have been done using event-by-event hydrodynamic

  81. Paolo Guasoni, Johannes Muhle-Karbe

    Recent progress in portfolio choice has made a wide class of problems involving transaction costs tractable. We review the basic approach to these problems, and outline some directions for future research.

  82. Camilo Delgado-Correal, José E. García

    It does a revision about the physical principles involved in digital processing of satellite images, more specifically in radiometric calibration of them. It shows a conceptual description of the interaction between radiation and atmosphere and radiation and soil in order to help the reader understand in more detail which means the information contained in s

  83. Federico R. Urban, Tomi K. Koivisto

    We reconsider magnetogenesis in the context of three-form inflation, and its backreaction. In particular, we focus on first order perturbation theory during inflation and subsequent radiation era: we discuss the consistency of the perturbative approach, and elaborate on the possible non-Gaussian signatures of the model.

  84. Adam Bzdak, Volker Koch, Jinfeng Liao

    We provide a phenomenological analysis of present experimental searches for local parity violation manifested through the Chiral Magnetic Effect. We introduce and discuss the relevant correlation functions used for the measurements. Our analysis of the available data from both RHIC and LHC shows that the present experimental evidence for the Chiral Magnetic

  85. Adam S. Bolton, David J. Schlegel, Eric Aubourg, Stephen Bailey

    (abridged) We describe the automated spectral classification, redshift determination, and parameter measurement pipeline in use for the Baryon Oscillation Spectroscopic Survey (BOSS) of the Sloan Digital Sky Survey III (SDSS-III) as of Data Release 9, encompassing 831,000 moderate-resolution optical spectra. We give a review of the algorithms employed, and d

  86. Michael Gutperle, Joshua Samani

    Solutions of $(d+1)$-dimensional gravity coupled to a scalar field are obtained, which holographically realize interface and boundary CFTs. The solution utilizes a Janus-like $\mathrm{AdS}_d$ slicing ansatz and corresponds to a deformation of the CFT by a spatially-dependent coupling of a relevant operator. The BCFT solutions are singular in the bulk, but ph

  87. Orlando Oliveira, Paulo J. Silva

    We study the Landau gauge gluon propagator at zero and finite temperature using lattice simulations. Particular attention is given to the finite size effects and to the infrared behaviour.

  88. L. Ya. Glozman, C. B. Lang, M. Schröck

    Chiral symmetry breaking in Quantum Chromodynamics is associated with the low lying spectral modes of the Dirac operator according to the Banks-Casher relation. Here we study how removal of a variable number of low lying modes from the valence quark sector affects the masses of the ground states and first excited states of baryons and mesons in two flavor la

  89. Jelena Klinovaja, Peter Stano, Daniel Loss

    We study hybrid superconducting-semiconducting nanowires in the presence of Rashba spin-orbit interaction as well as helical magnetic fields. We show that the interplay between them leads to a competition of phases with two topological gaps closing and reopening, resulting in unexpected reentrance behavior. Besides the topological phase with localized Majora

  90. Mohsen Bayati, Marc Lelarge, Andrea Montanari

    We consider a class of nonlinear mappings $\mathsf{F}_{A,N}$ in $\mathbb{R}^N$ indexed by symmetric random matrices $A\in\mathbb{R}^{N\times N}$ with independent entries. Within spin glass theory, special cases of these mappings correspond to iterating the TAP equations and were studied by Bolthausen [Comm. Math. Phys. 325 (2014) 333-366]. Within information

  91. D. Haranath, Sonal Sahai, Mushahid Husain, Savvi Mishra

    We present a novel, cost-effective and facile technique, wherein multi-walled carbon nano-tubes (CNTs) were used to transform a photoluminescent material to exhibit stable and efficient electroluminescence (EL) at low-voltages. As a case study, a commercially available ZnS:Cu phosphor (P-22G) was combined with a very low concentration of CNTs dispersed in et

  92. Paul Meuffels, Rohit Soni

    In 2008, researchers at the Hewlett-Packard (HP) laboratories claimed to have found an analytical physical model for a genuine memristor device [1]. The model is considered for a thin TiO_2 film containing a region which is highly self-doped with oxygen vacancies and a region which is less doped, i.e., a single-phase material with a built-in chemical inhomog

  93. Francisco Guinea, Bruno Uchoa

    Vertical graphene heterostructures made up of graphene layers separated by BN spacers allow for novel ways of tuning the interactions between electrons. We study the possibility of electron pairing mediated by modified repulsive interactions. Long range intravalley and short range intervalley interactions give rise to different anisotropic phases. We show th

  94. S. Albeverio, S. V. Kozyrev

    We introduce a lattice model of protein conformations which is able to reproduce second structures of proteins (alpha--helices and beta--sheets). This model is based on the following two main ideas. First, we model backbone parts of amino acid residues in a peptide chain by edges in the cubic lattice which are not parallel to the coordinate axes. Second, we

  95. D. A. Johnston, M. S. Stringer

    We investigate the partially asymmetric exclusion process (PASEP) with open boundaries when the reverse hopping rate of particles q=-1, using a representation of the PASEP algebra related to the al-Salam Chihara polynomials. When q=-1 the representation is two-dimensional, which allows for straightforward calculation of the normalization, current and density

  96. O. Buchmueller, R. Cavanaugh, M. Citron, A. De Roeck

    We make a frequentist analysis of the parameter space of the CMSSM and NUHM1, using a Markov Chain Monte Carlo (MCMC) with 95 (221) million points to sample the CMSSM (NUHM1) parameter spaces. Our analysis includes the ATLAS search for supersymmetric jets + MET signals using ~ 5/fb of LHC data at 7 TeV, which we apply using PYTHIA and a Delphes implementatio

  97. Andreas Svedin, Milena C. Cuellar, Axel Brandenburg

    We show how the 3DVAR data assimilation methodology can be used in the astrophysical context of a two-dimensional convection flow. We study the way this variational approach finds best estimates of the current state of the flow from a weighted average of model states and observations. We use numerical simulations to generate synthetic observations of a verti

  98. Vesselin I. Dimitrov

    The problem of assigning probabilities when little is known is analized in the case where the quanities of interest are physical observables, i.e. can be measured and their values expressed by numbers. It is pointed out that the assignment of probabilities based on observation is a process of inference, involving the use of Bayes' theorem and the choice of a

  99. N. G. Almarza, J. M. Tavares, M. M. Telo da Gama

    We investigate the nature of the ordered phase and the orientational correlations between adjacent layers of the confined three-dimensional self-assembled rigid rod model, on the cubic lattice. We find that the ordered phase at finite temperatures becomes uniaxial in the thermodynamic limit, by contrast to the ground state (partial) order where the orientati

  100. Marco Piazzi, Luca Croin, Ettore Vittone, Giampiero Amato

    The outstanding electrical and mechanical properties of graphene make it very attractive for several applications, Nanoelectronics above all. However a reproducible and non destructive way to produce high quality, large-scale area, single layer graphene sheets is still lacking. Chemical Vapour Deposition of graphene on Cu catalytic thin films represents a pr