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May 2009 arXiv papers — page 7

Showing 601700 of 5,084 papers

  1. Min-Su Shin, Jeremiah P. Ostriker, Luca Ciotti

    By using high-resolution 1D hydrodynamical simulations, we investigate the effects of purely mechanical feedback from super massive black holes (SMBHs) in the evolution of elliptical galaxies for a broad range of feedback efficiencies and compare the results to four major observational constraints. In particular, we focus on 1) the central black hole to stel

  2. J. Aldegunde, Hong Ran, Jeremy M. Hutson

    We calculate the microwave spectra of ultracold KRb alkali metal dimers, including hyperfine interactions and in the presence of electric and magnetic fields. We show that microwave transitions may be used to transfer molecules between different hyperfine states, but only because of the presence of nuclear quadrupole interactions. Hyperfine splittings may al

  3. J. D. Hague, B. R. Becker, M. S. Gold, J. A. J. Matthews

    The two-point angular correlation function is a traditional method used to search for deviations from expectations of isotropy. In this paper we develop and explore a statistically descriptive three-point method with the intended application being the search for deviations from isotropy in the highest energy cosmic rays. We compare the sensitivity of a two-p

  4. Pawel Sosna

    We show that there exist a complex projective K3 surface $X$ and an automorphism of the complex numbers $σ$ such that the conjugate K3 surface $X^σ$ is a non-isomorphic Fourier-Mukai partner of $X$.

  5. Shuai Dong, Rong Yu, J. -M. Liu, Elbio Dagotto

    The phase diagram of quarter-hole-doped perovskite manganites is investigated using the doubleexchange model. An exotic striped type-II multiferroic phase, where 25% of the nearest-neighbor spin couplings are orthogonal to each other, is found in the narrow-bandwidth region. Comparing with the spiral-spin ordering phase of undoped manganites, the multiferroi

  6. Sang-Bum Lee, Juhee Yang, Songky Moon, Soo-Young Lee

    We present spectroscopic observation of an exceptional point or the transition point between diabatic crossing and avoided crossing of neighboring quasi-eigenmodes in a chaotic optical microcavity with a large size parameter. The transition to the avoided crossing was impeded until the degree of deformation exceeded a threshold deformation owing to the syste

  7. J. Scott Carter, Masahico Saito

    An algebraic system is proposed that represent surface cobordisms in thickened surfaces. Module and comodule structures over Frobenius algebras are used for representing essential curves. The proposed structure gives a unified algebraic view of states of categorified Jones polynomials in thickened surfaces and virtual knots. Constructions of such system are

  8. Joseph D. Meiring, James T. Lauroesch, Varsha P. Kulkarni, Celine Peroux

    We have combined the results from our recent observations of Damped and sub-Damped Lyman-alpha systems with the MIKE and UVES spectrographs on the Magellan Clay and VLT Kueyen telescopes with ones from the literature to determine the N(HI)-weighted mean metallicity of these systems based both on Fe, a depleted element in QSO absorbers and the local ISM, and

  9. Mukund Rangamani

    We discuss recent developments in the hydrodynamic description of strongly coupled conformal field theories using the AdS/CFT correspondence. In particular, we review aspects of the fluid-gravity correspondence which provides a map between a class of inhomogeneous, dynamical, black hole solutions in asymptotically AdS spacetimes and arbitrary fluid flows in

  10. Maria B. Lifshits, Michel I. Dyakonov

    We introduce a previously unknown spin-related transport phenomenon, consisting in a transformation (swapping) of spin currents, in which the spin direction and the direction of flow are interchanged. Swapping is due to the spin-orbit interaction in scattering. It originates from the correlation between the spin rotation and the scattering angle. This effect

  11. Bert Schroer

    It is shown that certain kinds of behavior, which hitherto were expected to be characteristic for classical gravity and quantum field theory in curved spacetime, as the infinite dimensional Bondi-Metzner-Sachs symmetry, holography on event horizons and an area proportionality of entropy, have in fact an unnoticed presence in Minkowski QFT. This casts new lig

  12. S. Groote, J. G. Körner, J. A. Leyva

    We provide analytical results for the $O(α_s)$ corrections to the polar angle dependence of the longitudinal spin-spin correlation asymmetry in $e^+e^-\to q\bar q$. For top quark pair production the $O(α_s)$ corrections to the longitudinal spin-spin asymmetry are strongly polar angle dependent and can amount up to $4\%$ in the $q^2$-range from above $t\bar t

  13. Y. -M. Xu, P. Richard, K. Nakayama, T. Kawahara

    High-temperature superconductivity in iron-arsenic materials (pnictides) near an antiferromagnetic phase raises the possibility of spin-fluctuation-mediated pairing. However, the interplay between antiferromagnetic fluctuations and superconductivity remains unclear in the underdoped regime, which is closer to the antiferromagnetic phase. Here we report that

  14. V. Shary

    An overview of the recent measurements of the top antitop quark pair production cross section in proton antiproton collisions at \sqrt{s}=1.96 TeV in lepton + jets and dilepton final states is presented. These measurements are based on 1 -- 2.8 fb^{-1} of data collected with the D0 and CDF experiments at the Fermilab Tevatron collider. The cross section is m

  15. C. Balázs, N. Sahu, A. Mazumdar

    We extract the positron and electron fluxes in the energy range 10 - 100 GeV by combining the recent data from PAMELA and Fermi LAT. The {\it absolute positron and electron} fluxes thus obtained are found to obey the power laws: $E^{-2.65}$ and $E^{-3.06}$ respectively, which can be confirmed by the upcoming data from PAMELA. The positron flux appears to ind

  16. Colin Morningstar

    Progress in extracting the spectrum of excited hadron resonances in lattice QCD Monte Carlo calculations is reviewed and the key issues and challenges in such computations are outlined. The importance of multi-hadron states as simulations with lighter pion masses are done is discussed, and the need for all-to-all quark propagators is emphasized.

  17. Serena Bradde, Ginestra Bianconi

    Correlations are known to play a crucial role in determining the structure of complex networks. Here we study how their presence affects the computation of the percolation threshold in random hypergraphs. In order to mimic the correlation in real network, we build hypergraphs from a generalized hidden variable ensembles and we study the percolation transitio

  18. C. Sauvan, J. P. Hugonin, P. Lalanne

    Different mirror geometries in two-dimensional photonic crystal slabs are studied with fully-vectorial calculations. We compare their optical properties and, in particular, we show that, for heterostructure mirrors, the penetration length associated with the delay induced by distributed reflection is not correlated to the characteristic damping length of the

  19. Joel Ekstrand, Reimundo Heluani, Johan Kallen, Maxim Zabzine

    We propose a physical interpretation of the chiral de Rham complex as a formal Hamiltonian quantization of the supersymmetric non-linear sigma model. We show that the chiral de Rham complex on a Calabi-Yau manifold carries all information about the classical dynamics of the sigma model. Physically, this provides an operator realization of the non-linear sigm

  20. Oscar Marmon

    The so-called determinant method was developed by Bombieri and Pila in 1989 for counting integral points of bounded height on affine plane curves. In this paper we give a generalization of that method to varieties of higher dimension, yielding a proof of Heath-Brown's 'Theorem 14' by real-analytic considerations alone.

  21. Otfried Cheong, Antoine Vigneron, Juyoung Yon

    Reverse nearest neighbor queries are defined as follows: Given an input point-set P, and a query point q, find all the points p in P whose nearest point in P U {q} \ {p} is q. We give a data structure to answer reverse nearest neighbor queries in fixed-dimensional Euclidean space. Our data structure uses O(n) space, its preprocessing time is O(n log n), and

  22. Oliver Bär, Willi Rath, Ulli Wolff

    We investigate the discrete chiral transformation of a Majorana fermion on a torus. Depending on the boundary conditions the integration measure can change sign. Taking this anomalous behavior into account we define a chiral order parameter as a ratio of partition functions with differing boundary conditions. Then the lattice realization of the Gross-Neveu m

  23. Kazim Buyukboduk

    In this paper we prove a formula, much in the spirit of one due to Rubin, which expresses the leading coefficients of various p-adic L-functions in the presence of an exceptional zero in terms of Nekovar's p-adic height pairings on his extended Selmer groups. In a particular case, the Rubin-style formula we prove recovers a p-adic Kronecker limit formula

  24. S. Kasahara, T. Shibauchi, K. Hashimoto, K. Ikada

    The normal-state charge transport is studied systematically in high-quality single crystals of BaFe$_2$(As$_{1-x}$P$_x$)$_2$ ($0 \leq x \leq 0.71$). By substituting isovalent P for As, the spin-density-wave (SDW) state is suppressed and the dome-shaped superconducting phase ($T_c \lesssim 31$ K) appears. Near the SDW end point ($x\approx0.3$), we observe str

  25. D. Faccio, S. Cacciatori, V. Gorini, V. G. Sala

    Ultrashort laser pulse filaments in dispersive nonlinear Kerr media induce a moving refractive index perturbation which modifies the space-time geometry as seen by co-propagating light rays. We study the analogue geometry induced by the filament and show that one of the most evident features of filamentation, namely conical emission, may be precisely reconst

  26. A. Chepurnov, A. Lazarian

    We use the data of Wisconsin H$α$ Mapper (WHAM) to test the hypothesis of whether the amplitudes and spectrum of density fluctuations measured by WHAM can be matched to the data obtained for interstellar scintillations and scattering. To do this, first of all, we adjusted the mean level of signal in the adjacent patches of the data. Then, assuming that the s

  27. Andreas Eberle, Carlo Marinelli

    We introduce a class of time-inhomogeneous transition operators of Feynman-Kac type that can be considered as a generalization of symmetric Markov semigroups to the case of a time-dependent reference measure. Applying weighted Poincaré and logarithmic Sobolev inequalities, we derive L^p-L^p and L^p-L^q estimates for the transition operators. Since the operat

  28. D. C. Bell, M. C. Lemme, L. A. Stern, J. R. Williams

    We report nanoscale patterning of graphene using a helium ion microscope configured for lithography. Helium ion lithography is a direct-write lithography process, comparable to conventional focused ion beam patterning, with no resist or other material contacting the sample surface. In the present application, graphene samples on Si/SiO2 substrates are cut us

  29. M. C. Lemme, D. C. Bell, J. R. Williams, L. A. Stern

    We report on the etching of graphene devices with a helium ion beam, including in situ electrical measurement during lithography. The etching process can be used to nanostructure and electrically isolate different regions in a graphene device, as demonstrated by etching a channel in a suspended graphene device with etched gaps down to about 10 nm. Graphene d

  30. M. Grigorescu

    The basic elements of the geometric approach to a consistent quantization formalism are summarized, with reference to the methods of the old quantum mechanics and the induced representations theory of Lie groups. A possible relationship between quantization and discretization of the configuration space is briefly discussed.

  31. E. Vitali, M. Rossi, L. Reatto, D. E. Galli

    We have extracted information about real time dynamics of 4He systems from noisy imaginary time correlation functions f(tau) computed via Quantum Monte Carlo (QMC): production and falsification of model spectral functions s(omega) are obtained via a survival-to-compatibility with f(tau) evolutionary process, based on Genetic Algorithms. Statistical uncertain

  32. Sergiu I. Vacaru

    We model pseudo-Finsler geometries, with pseudo-Euclidean signatures of metrics, for two classes of four dimensional nonholonomic manifolds: a) tangent bundles with two dimensional base manifolds and b) pseudo-Riemannian/ Einstein manifolds. Such spacetimes are enabled with nonholonomic distributions and associated nonlinear connection structures and theirs

  33. Kausik Pal, Subhrajyoti Biswas, Abhee K. Dutt-Mazumder

    We calculate the ground state energy of cold and dense spin polarized quark matter with corrections due to correlation energy $(E_{corr})$. Expressions for $E_{corr}$ both in the non-relativistic and ultra-relativistic regimes have been derived and compared with the exchange and kinetic term present in the perturbation series. It is observed that the inclusi

  34. Roberto Chignola, Marcello Farina, Alessio Del Fabbro, Edoardo Milotti

    Tumor Necrosis Factor alpha (TNF) initiates a complex series of biochemical events in the cell upon binding to its type R1 receptor (TNF-R1). Recent experimental work has unravelled the molecular regulation of the recruitment of initial signaling complexes that lead either to cell survival or death. Survival signals are activated by direct binding of TNF to

  35. M. M. Glazov, E. L. Ivchenko

    We develop a theory of effects of electron-electron collisions on the Dyakonov-Perel' spin relaxation in multi-valley quantum wells. It is shown that the electron-electron scattering rate which governs the spin relaxation is different from that in a single-valley system. The theory is applied to Si/SiGe (001)-grown quantum wells where two valleys are sim

  36. Michael Rowan-Robinson, Ivan Valtchanov, Kirpal Nandra

    We have combined the CLASXS Chandra survey in Lockman with the Spitzer SWIRE survey data to study the X-ray-infrared connection for AGN. The sample consists of 401 X-ray-sources, of which 306 are detected by Spitzer, and a further 257 AGN candidates detected through their dust torus, but not by Chandra. For X-ray sources the X-ray hardness ratio has been mod

  37. Carla Novelli, Gianluca Occhetta

    We prove that Generalized Mukai Conjecture holds for Fano manifolds $X$ of pseudoindex $i_X \ge (\dim X +3)/3$. We also give different proofs of the conjecture for Fano fourfolds and fivefolds.

  38. Nikita Semenov

    Let G be a group of type E8 of compact type over the field of rational numbers, let K be a field of characteristic 0, and q the 5-fold Pfister form which is the sum of 32 squares. J-P. Serre posed in a letter to M. Rost written on June 23, 1999 the following problem: Is it true that G is split over K if and only if q is hyperbolic over K? In the present arti

  39. Zvika Ben-Haim, Yonina C. Eldar

    The goal of this paper is to characterize the best achievable performance for the problem of estimating an unknown parameter having a sparse representation. Specifically, we consider the setting in which a sparsely representable deterministic parameter vector is to be estimated from measurements corrupted by Gaussian noise, and derive a lower bound on the me

  40. J. Schnack

    Investigations of molecular magnets are driven both by prospective applications in future storage technology or quantum computing as well as by fundamental questions. Nowadays numerical simulation techniques and computer capabilities make it possible to investigate spin Hamiltonians with realistic arrangements of local anisotropy tensors. In this contributio

  41. Jorge V. Rocha

    We consider a massless, minimally coupled scalar field propagating through the geometry of a black 3-brane in an asymptotically $AdS_5 \times S^5$ space. The wave equation for modes traveling purely in the holographic direction reduces to a Heun equation and the corresponding greybody factor is obtained numerically. Approximations valid in the low- and high-

  42. Alessandro Conflitti, Ricardo Mamede

    We present an explicit bijection between noncrossing and nonnesting partitions of Coxeter systems of type D which preserves openers, closers and transients.

  43. Roy A. Lacey, Arkadij Taranenko, Rui Wei

    Recent hexadecapole (v4) and elliptic (v2) flow measurements are used to constrain estimates for the degree of local equilibrium, mean free path $λ$, and the viscosity to entropy density ratio (eta/s) of the plasma produced in Au+Au collisions at RootS = 200 GeV. The eccentricity-scaled flow coefficients v2/e2 and v4/e4 indicate that the plasma achieves a de

  44. Samuel Boissiere, Alessandra Sarti

    We give a necessary and sufficient condition for an automorphism of the Hilbert scheme of points on a K3 surface (non necessarily algebraic) to be induced by an automorphism of the surface. We prove furthermore that the group of birational transformations of a projective irreducible holomorphic symplectic manifold is finitely generated.

  45. S. Campbell, M. Paternostro

    The ability to teleport entanglement through maximally entangled mixed states as defined by concurrence and linear entropy is studied. We show how the teleported entanglement depends on the quality of the quantum channel used, as defined through its entanglement and mixedness, as well as the form of the target state to be teleported. We present new results b

  46. Xavier Bardina, David Bascompte

    We consider two independent Gaussian processes that admit a representation in terms of a stochastic integral of a deterministic kernel with respect to a standard Wiener process. In this paper we construct two families of processes, from a unique Poisson process, the finite dimensional distributions of which converge in law towards the finite dimensional dist

  47. H. R. Schmidt

    ALICE at CERN-LHC is an experiment dedicated to the study of high-energy heavy-ion collision. In this paper we will briefly describe the experimental layout and give an overview on the installation status of the ALICE detector components including an outlook towards the completion of the staged detector setup. We will review the commissioning of the detector

  48. Kuan Yen Tan, Kok Wai Chan, Mikko Möttönen, Andrea Morello

    We have developed nano-scale double-gated field-effect-transistors for the study of electron states and transport properties of single deliberately-implanted phosphorus donors. The devices provide a high-level of control of key parameters required for potential applications in nanoelectronics. For the donors, we resolve transitions corresponding to two charg

  49. Stéphane Faure, Christelle Brimont, Thierry Guillet, T. Bretagnon

    The strong coupling regime in a ZnO microcavity is investigated through room temperature photoluminescence and reflectivity experiments. The simultaneous strong coupling of excitons to the cavity mode and the first Bragg mode is demonstrated at room temperature. The polariton relaxation is followed as a function of the excitation density. A relaxation bottle

  50. Xavier Guitart

    This paper investigates the fields of definition up to isogeny of the abelian varieties called building blocks. A result of Ribet characterizes the fields of definition of these varieties together with their endomorphisms, in terms of a Galois cohomology class canonically attached to them. However, when the building blocks have quaternionic multiplication, t

  51. Brett Altschul

    Some deviations from special relativity--especially isotropic effects--are most efficiently constrained using particles with velocities very close to 1. While there are extremely tight bounds on some of the relevant parameters coming from astrophysical observations, many of these rely on our having an accurate understanding of the dynamics of high-energy sou

  52. R. Louvot

    The data sample recorded with the Belle detector at the KEKB B factory (Tsukuba, Japan) operating at the Y(5S) energy provides interesting and new results about the Bs0 mesons and the Y(5S) resonance. Recent analyses, based on data samples collected at the Y(5S) resonance (23.6 /fb) or near it (7.9 /fb), are presented with a special focus on the final result

  53. P. Karmakar, S. Bhattacharjee, V. Naik, A. K. Sinha

    We have studied multiply charged Arq+ ion induced potential sputtering of a unique system comprising of coexisting Silicon and Silicon oxide surfaces. Such surfaces are produced by oblique angle oxygen ion bombardment on Si(100), where ripple structures are formed and one side of each ripple gets more oxidized. It is observed that higher the potential energy

  54. Makoto Ozawa

    We introduce two numerical invariants, the waist and the trunk of knots. The waist of a closed incompressible surface in the complement of a knot is defined as the minimal intersection number of all compressing disks for the surface in the 3-sphere and the knot. Then the waist of a knot is defined as the maximal waist of all closed incompressible surfaces in

  55. Ari Stern

    We present a discrete analog of the recently introduced Hamilton-Pontryagin variational principle in Lagrangian mechanics. This unifies two, previously disparate approaches to discrete Lagrangian mechanics: either using the discrete Lagrangian to define a finite version of Hamilton's action principle, or treating it as a symplectic generating function. This

  56. Sangheon Yun

    In this note, we apply a special metric ansatz to simplify the equations of motion for gravitational systems. Then we construct charged brane solutions in $D=n+p+2$ dimensions which have spherical symmetry of $S^n$ and translational symmetry along $p$ directions. They are characterized by mass density, uniform tension and electric/magnetic charges, and nonsi

  57. Shun-Fang Liu, Zhen-Yu Wu, Xiao-Bin Zhang, Jiang-Hua Wu

    We report the results of a time-series CCD photometric survey of variable stars in the field of the open cluster NGC 2126. In about one square degree field covering the cluster, a total number of 21 variable candidates are detected during this survey, of which 16 are newly found. The periods, classifications and spectral types of 14 newly discovered variable

  58. David Solomon

    We introduce a new ideal {\mathfrak D} of the p-adic Galois group-ring associated to a real abelian field and a related ideal {\mathfrak J} for imaginary abelian fields. Both result from an equivariant, Kummer-type pairing applied to Stark units in a Z_p-tower of abelian fields and {\mathfrak J} is linked by explicit reciprocity to a third ideal {\mathfrak S

  59. R. Liptser

    We consider a classical model related to an empirical distribution function $ F_n(t)=\frac{1}{n}\sum_{k=1}^nI_{\{ξ_k\le t\}}$ of $(ξ_k)_{i\ge 1}$ -- i.i.d. sequence of random variables, supported on the interval $[0,1]$, with continuous distribution function $F(t)=\mathsf{P}(ξ_1\le t)$. Applying ``Stopping Time Techniques'', we give a proof of Kolmog

  60. Mikhail Gorchtein

    Virtual Compton scattering off the nucleon (VCS) is studied in the regime of low energy of the outgoing real photon. This regime allows one to directly access the generalized polarizabilities of the nucleon in a VCS experiment. In the derivation of the low energy theorem for VCS that exists in the literature, the low energy limit taken for virtual initial ph

  61. Bijan Bagchi, Toshiaki Tanaka

    Type A N-fold supercharge admits a one-parameter family of factorizations into product of N first-order linear differential operators due to an underlying GL(2,C) symmetry. As a consequence, a type A N-fold supersymmetric system can have different intermediate Hamiltonians corresponding to different factorizations. We derive the necessary and sufficient cond

  62. Tomohiro Matsuda

    A new scenario of hybrid-like inflation is considered for sneutrino and MSSM fields. Contrary to the usual hybrid inflation model, the direct coupling between a trigger field and the sneutrino/MSSM inflaton field is not necessary for the scenario. The dissipation and the radiation from the sneutrino/MSSM inflaton can be written explicitly by using the Yukawa

  63. Makoto Sakamoto

    We solve a renormalized Wheeler-DeWitt equation for Einstein gravity in D+1 dimensions with D= odd in the strong coupling limit, which is expected to be suited to probe quantum geometry at short distances, in order to test Horava's idea that quantum gravity at short distances will be described by a nonrelativistic system with dynamical critical exponent

  64. Lie-Wen Chen, Bao-Jun Cai, Che Ming Ko, Bao-An Li

    Analytical expressions for the saturation density as well as the binding energy and incompressibility at the saturation density of asymmetric nuclear matter are given exactly up to 4th-order in the isospin asymmetry delta =(rho_n - rho_p)/rho using 11 characteristic parameters defined at the normal nuclear density rho_0. Using an isospin- and momentum-depend

  65. Gavril Giurgiu

    We present recent CDF measurements of mass, lifetime and CP violation properties of B hadrons. The analyzes presented in this paper use up to 2.8/fb of data. CDF has already accumulated close to 5/fb of data which promises significant improvements of these analyzes in the near future.

  66. Jiulin Du

    The dynamical property of the Tsallis distribution is studied from a Fokker-Planck equation. For the Langevin dynamical system with an arbitrary potential function, Markovian friction and Gaussian white noise, we show that no possible nonequilibrium dynamics can use the Tsallis distribution for the statistical description. The current form of the Tsallis dis

  67. Jonas Azzam

    We prove that there exists $M>0$ such that for any closed rectifiable curve $Γ$ in Hilbert space, almost every point in $Γ$ is contained in a countable union of $M$ chord-arc curves whose total length is no more than $M$ times the length of $Γ$.

  68. Bingbing Wang, Yingchun Guo, Zong-Chao Yan, Panming Fu

    Using the frequency-domain theory, the high-order above threshold ionization (HATI) of a molecule is treated as a two-step transition: an above threshold ionization (ATI) followed by a laser-assisted collision (LAC). It is found that the HATI spectrum carries three pieces of information: the fingerprint of the molecular wave function lying in the ATI transit

  69. H. Ohldag, P. Esquinazi, E. Arenholz, D. Spemann

    We present a x-ray dichroism study of graphite surfaces that addresses the origin and magnitude of ferromagnetism in metal-free carbon. We find that, in addition to carbon $π$ states, also hydrogen-mediated electronic states exhibit a net spin polarization with significant magnetic remanence at room temperature. The observed magnetism is restricted to the to

  70. Kaoru Hagiwara, Qiang Li, Kentarou Mawatari

    Higgs boson and massive-graviton productions in association with two jets via vector-boson fusion (VBF) processes and their decays into a vector-boson pair at hadron colliders are studied. They include scalar and tensor boson production processes via weak-boson fusion in quark-quark collisions, gluon fusion in quark-quark, quark-gluon and gluon-gluon collisi

  71. Sadaharu Uehara

    The X(3872) and Z(4430) are candidates of tetraquark state with a ccbar pair. We present results from Belle recently updated for the mass, branching fractions etc. in different production/decay processes of the X(3872). Results from a Dalitz analysis for B --> Z(4430) K --> psi' pi^+- K are also presented.

  72. Filipe B. Abdalla, Chris Blake, Steve Rawlings

    We use two independent methods to forecast the dark energy measurements achievable by combining future galaxy redshift surveys based on the radio HI emission line with Cosmic Microwave Background (CMB) data from the {\sl Planck} satellite. In the first method we focus on the `standard ruler' provided by the baryon acoustic oscillation (BAO) length scale.

  73. Rui Liu, Yan Xu, Haimin Wang

    We revisit the flare on 1992 January 13, which is now universally termed the "Masuda flare". The revisit is motivated not only by its uniqueness despite accumulating observations of \hxr coronal emission, but also by the improvement of Yohkoh hard X-ray imaging, which was achieved after the intensive investigations on this celebrated event. Through a

  74. Paul M. B. Vitanyi

    Unlimited asynchronism is intolerable in real physically distributed computer systems. Such systems, synchronous or not, use clocks and timeouts. Therefore the magnitudes of elapsed absolute time in the system need to satisfy the axiom of Archimedes. Under this restriction of asynchronicity logically time-independent solutions can be derived which are noneth

  75. The BABAR Collaboration, B. Aubert

    We search for evidence of a light scalar boson in the radiative decays of the Upsilon(2S) and Upsilon(3S) resonances: Upsilon(2S,3S)-> gamma A0, A0 -> mu^+ mu^-. Such a particle appears in extensions of the Standard Model, where a light CP-odd Higgs boson naturally couples strongly to b-quarks. We find no evidence for such processes in the mass range 0.212<=

  76. Hans-Jurgen Bandelt, Victor Chepoi, David Eppstein

    Squaregraphs were originally defined as finite plane graphs in which all inner faces are quadrilaterals (i.e., 4-cycles) and all inner vertices (i.e., the vertices not incident with the outer face) have degrees larger than three. The planar dual of a finite squaregraph is determined by a triangle-free chord diagram of the unit disk, which could alternatively

  77. Abebe Kebede, Terrel Dial

    Structural, electrical and magnetic measurements of 115 single crystals of PrIn$_5$ are reported. It has a tetragonal structure and has slightly lower cell volume than its isomorphic counter part CeCoIn_5. The resistivity saturates for T\geq 10K. Analysis of the resistivity for 10K<T< 60K indicates a regular fermi liquid behavior. It does not exhibit superco

  78. Geng Tian, Luoyi Shi, Sen Zhu, Bingzhe Hou

    As well-known, the concept &#34;hypercyclic&#34; in operator theory is the same as the concept &#34;transitive&#34; in dynamical system. Now the class of hypercyclic operators is well studied. Following the idea of research in hypercyclic operators, we consider classes of operators with some kinds of chaotic properties in this article. First of all, the clos

  79. Mariusz P. Dabrowski, Janusz Garecki

    The superenergy of the universe is a tensorial quantity and it is a general relativistic analogue of the Appell's energy of acceleration in classical mechanics. We propose the measurement of this quantity by the observational parameters such as the Hubble parameter, the deceleration parameter, the jerk and the snap (kerk) known as statefinders. We show that

  80. Sankaran Viswanath

    We study $t$-analogs of string functions for integrable highest weight representations of the affine Kac-Moody algebra $A_1^{(1)}$. We obtain closed form formulas for certain $t$-string functions of levels 2 and 4. As corollaries, we obtain explicit identities for the corresponding affine Hall-Littlewood functions, as well as higher-level generalizations of

  81. Arjun Dey, the NDWFS/MIPS Collaboration

    A simple mid-infrared-to-optical color criterion of R-[24]>14 Vega mag results in a robust selection of approximately half of the redshift 2 ultraluminous infrared galaxy (ULIRG) population. These `Dust-Obscured Galaxies&#39;, or DOGs, have many properties that suggest that they are good candidates for systems in a transition phase between gas-rich mergers a

  82. Carlos Maquera, Carlos Biasi

    We show that if $N$, an open connected $n$-manifold with finitely generated fundamental group, is $C^{2}$ foliated by closed planes, then $π_{1}(N)$ is a free group. This implies that if $π_{1}(N)$ has an Abelian subgroup of rank greater than one, then $\mathcal{F}$ has at least a non closed leaf. Next, we show that if $N$ is three dimensional with fundament

  83. Rosalind E. Skelton, Eric F. Bell, Rachel S. Somerville

    We investigate the effect of dry merging on the color-magnitude relation (CMR) of galaxies and find that the amount of merging predicted by a hierarchical model results in a red sequence that compares well with the observed low-redshift relation. A sample of 29,000 early-type galaxies selected from the Sloan Digital Sky Survey Data Release 6 shows that the b

  84. Ajay S. Panwar, Mark A. Kelly, Buddhapriya Chakrabarti, M. Muthukumar

    We explore the mechanical response of a single polyelectrolyte chain under tension in good and poor solvents using a combination of simulation and theory. In poor solvents, where the equilibrium state of the chain is a collapsed globule, we find that the chain undergoes a globule-coil transition, as the magnitude of the force is increased beyond a critical v

  85. A. E. Glassgold, R. Meijerink, J. R. Najita

    The gas-phase chemistry of water in protoplanetary disks is analyzed with a model based on X-ray heating and ionization of the disk atmosphere. Several uncertain processes appear to play critical roles in generating the column densities of warm water that are detected from disks at infrared wavelengths. The dominant factors are the reactions that form molecu

  86. Guillaume Lutter

    The neutrino flavour oscillations hypothesis has been confirmed by several experiments, all are based on the observation of the disappearance of a given neutrino flavour. The long baseline neutrino experiment OPERA (Oscillation Project with Emulsion tRacking Apparatus) aims to give the first direct proof of the tau neutrino appearance in a pure muon neutrino

  87. Lennard F. Bakker, Tiancheng Ouyang, Skyler Simmons, Duokui Yan

    We apply the analytic-numerical method of Roberts to determine the linear stability of time-reversible periodic simultaneous binary collision orbits in the symmetric collinear four body problem with masses 1, m, m, 1, and also in a symmetric planar four-body problem with equal masses. For the collinear problem, this verifies the earlier numerical results of

  88. Steven Dale Cutkosky, Samar ElHitti

    Suppose that $R$ is a local domain essentially of finite type over a field of characteristic 0, and $ν$ a valuation of the quotient field of $R$ which dominates $R$. The rank of such a valuation often increases upon extending the valuation to a valuation dominating $\hat R$, the completion of $R$. When the rank of $ν$ is 1, Cutkosky and Ghezzi handle this ph

  89. Sunil Abraham, Greg Brockman, Stephanie Sapp, Anant P. Godbole

    An {\it Omnibus Sequence} of length $n$ is one that has each possible &#34;message&#34; of length $k$ embedded in it as a subsequence. We study various properties of Omnibus Sequences in this paper, making connections, whenever possible, to the classical coupon collector problem.

  90. M. V. T. Machado

    In this contribution, we present a study of the coherent and incoherent nuclear DVCS process in the small-$x$ regime within the color dipole formalism. Predictions for the nuclear DVCS cross section at photon level in the collider kinematics are presented.

  91. Bryan K. Clark, Michele Casula, D. M. Ceperley

    We study the Wigner crystal melting in a two dimensional quantum system of particles interacting via the 1/r Coulomb potential. We use quantum Monte Carlo methods to calculate its phase diagram, locate the Wigner crystal region, and analyze its instabilities towards the liquid phase. We discuss the role of quantum effects in the critical behavior of the syst

  92. Jon Gonzalez-Sanchez, Thomas S. Weigel

    A finite group $G$ is called {\it $p^i$-central of height $k$} if every element of order $p^i$ of $G$ is contained in the $k^{th}$-term $ζ_k(G)$ of the ascending central series of $G$. If $p$ is odd such a group has to be $p$-nilpotent (Thm. A). Finite $p$-central $p$-groups of height $p-2$ can be seen as the dual analogue of finite potent $p$-groups, i.e.,

  93. Upendra Harbola, Alexandre Rosas, Massimiliano Esposito, Katja Lindenberg

    We study pulse propagation in one-dimensional tapered chains of spherical granules. Analytic results for the pulse velocity and other pulse features are obtained using a binary collision approximation. Comparisons with numerical results show that the binary collision approximation provides quantitatively accurate analytic results for these chains.

  94. Daniel J. H. Chung, Bjorn Garbrecht, Michael J. Ramsey-Musolf, Sean Tulin

    We investigate the impact of the tau and bottom Yukawa couplings on the transport dynamics for electroweak baryogenesis in supersymmetric extensions of the Standard Model. Although it has generally been assumed in the literature that all Yukawa interactions except those involving the top quark are negligible, we find that the tau and bottom Yukawa interactio

  95. Gregory Rudnick, Anja von der Linden, Roser Pello, Alfonso Aragon-Salamanca

    We present the rest-frame optical luminosity function (LF) of red sequence galaxies in 16 clusters at 0.4<z<0.8 drawn from the ESO Distant Cluster Survey (EDisCS). We compare our clusters to an analogous sample from the Sloan Digital Sky Survey (SDSS) and match the EDisCS clusters to their most likely descendants. We measure all LFs down to M M* + (2.5 - 3.5

  96. A. S. Cohen, H. J. A. Röttgering

    High resolution (~1 arcminute) astronomical imaging at low frequency (below 150 MHz) has only recently become practical with the development of new calibration algorithms for removing ionospheric distortions. In addition to opening a new window in observational astronomy, the process of calibrating the ionospheric distortions also probes ionospheric structur

  97. Ian J. Parrish, Eliot Quataert, Prateek Sharma

    We examine the long-standing cooling flow problem in galaxy clusters with 3D MHD simulations of isolated clusters including radiative cooling and anisotropic thermal conduction along magnetic field lines. The central regions of the intracluster medium (ICM) can have cooling timescales of ~200 Myr or shorter--in order to prevent a cooling catastrophe the ICM

  98. V. Gurarie

    We study small oscillations of the order parameter in weakly and strongly paired superconductors driven slightly out of equilibrium, in the collisionless approximation. While it was known for quite some time that the amplitude of the oscillations in a weakly paired superconductor decays as 1/t^(1/2), we show that in a superconductor sufficiently strongly pai

  99. Mark I Frost, Jason Surace, Leonidas A Moustakas, Jessica Krick

    We have undertaken a systematic search for candidate supernovae from high-redshift Population III stars in a field that has been observed with repeated imaging on a cadence of 2-3 weeks over a 2.2 year baseline, the Spitzer/IRAC Dark Field. The individual epochs reach a typical 5-sigma depth of 1 uJy in IRAC Channel 1 (3.6 um). Requiring a minimum of four ep

  100. Jeppe Johansen, Brian Julsgaard, Søren Stobbe, Jørn M. Hvam

    The spin-flip rate that couples dark and bright excitons in self-assembled quantum dots is obtained from time-resolved spontaneous emission measurements in a modified local density of optical states. Employing this technique, we can separate effects due to non-radiative recombination and unambiguously record the spin-flip rate. The dependence of the spin-fli