November 2011 arXiv papers — page 4
Showing 301–400 of 7,304 papers
Martin Lemoine, Guy Pelletier
Relativistic sources, e.g. gamma-ray bursts, pulsar wind nebulae and powerful active galactic nuclei produce relativistic outflows that lead to the formation of collisionless shock waves, where particle acceleration is thought to take place. Our understanding of relativistic shock acceleration has improved in the past decade, thanks to the combination of ana
Jingchao Chen, Rongqing Zhang, Lingyang Song, Zhu Han
In this paper, we investigate joint relay and jammer selection in two-way cooperative networks, consisting of two sources, a number of intermediate nodes, and one eavesdropper, with the constraints of physical layer security. Specifically, the proposed algorithms select two or three intermediate nodes to enhance security against the malicious eavesdropper. T
Approximating fixed points of asymptotically nonexpansive mappings in Banach spaces by metric projections
math.FAHossein Dehghan
In this paper, a strong convergence theorem for asymptotically nonexpansive mappings in a uniformly convex and smooth Banach space is proved by using metric projections. This theorem extends and improves the recent strong convergence theorem due to Matsushita and Takahashi [ Appl. Math. Comput. 196 (2008) 422-425] which was established for nonexpansive mappi
On Bayesian "central clustering": Application to landscape classification of Western Ghats
stat.APSabyasachi Mukhopadhyay, Sourabh Bhattacharya, Kajal Dihidar
Landscape classification of the well-known biodiversity hotspot, Western Ghats (mountains), on the west coast of India, is an important part of a world-wide program of monitoring biodiversity. To this end, a massive vegetation data set, consisting of 51,834 4-variate observations has been clustered into different landscapes by Nagendra and Gadgil [Current Sc
L. Zhang, Lingyang Song, M. Ma, B. Jiao
In this paper, we consider a general multiple input multiple output (MIMO) system with channel state information (CSI) feedback over time-correlated Rayleigh block-fading channels. Specifically, we first derive the closed-form expression of the minimum differential feedback rate to achieve the maximum erdodic capacity in the presence of channel estimation er
Experimental scaling law for the sub-critical transition to turbulence in plane Poiseuille flow
physics.flu-dynGrégoire Lemoult, Jean-Luc Aider, José-Eduardo Wesfreid
We present an experimental study of transition to turbulence in a plane Poiseuille flow. Using a well-controlled perturbation, we analyse the flow using extensive Particule Image Velocimetry and flow visualisation (using Laser Induced Fluorescence) measurements and use the deformation of the mean velocity profile as a criterion to characterize the state of t
Lingyang Song, Zhu Han, Zhongshan Zhang, Bingli Jiao
It has been well recognized that channel state information (CSI) feedback is of great importance for dowlink transmissions of closed-loop wireless networks. However, the existing work typically researched the CSI feedback problem for each individual mobile station (MS), and thus, cannot efficiently model the interactions among self-interested mobile users in
Offer Kella
The goal is to identify the class of distributions to which the distribution of the maximum of a Lévy process with no negative jumps and negative mean (equivalently, the stationary distribution of the reflected process) belongs. An explicit new distributional identity is obtained for the case where the Lévy process is an independent sum of a Brownian motion
Yuriy Mishchenko, Liam Paninski
Monte Carlo approaches have recently been proposed to quantify connectivity in neuronal networks. The key problem is to sample from the conditional distribution of a single neuronal spike train, given the activity of the other neurons in the network. Dependencies between neurons are usually relatively weak; however, temporal dependencies within the spike tra
Arka Majumdar, Michal Bajcsy, Armand Rundquist, Erik Kim
We present experimental results showing phonon-mediated coupling between two quantum dots embedded inside a photonic crystal microcavity. With only one of the dots being spectrally close to the cavity, we observe both frequency up-conversion and down-conversion of the pump light via a $\sim1.2$ THz phonon. We demonstrate this process for both weak and strong
Multifractal analysis of the electronic states in the Fibonacci superlattice under weak electric fields
cond-mat.mes-hallMaciej Woloszyn, Bartlomiej J. Spisak
Influence of the weak electric field on the electronic structure of the Fibonacci superlattice is considered. The electric field produces a nonlinear dynamics of the energy spectrum of the aperiodic superlattice. Mechanism of the nonlinearity is explained in terms of energy levels anticrossings. The multifractal formalism is applied to investigate the effect
Gan Zheng, Symeon Chatzinotas, Bjorn Ottersten
Multibeam systems with hundreds of beams have been recently deployed in order to provide higher capacities by employing fractional frequency reuse. Furthermore, employing full frequency reuse and precoding over multiple beams has shown great throughput potential in literature. However, feeding all this data from a single gateway is not feasible based on the
V. Kobelev
The history of structural optimization as an exact science begins possibly with the celebrated Lagrange problem: to find a curve which by its revolution about an axis in its plane determines the rod of greatest efficiency. The Lagrange hypothesis, that the optimal rod possesses the constant cross-section was abandoned for Euler buckling problem. In this Arti
Juliette Blanchet, Anthony C. Davison
The spatial modeling of extreme snow is important for adequate risk management in Alpine and high altitude countries. A natural approach to such modeling is through the theory of max-stable processes, an infinite-dimensional extension of multivariate extreme value theory. In this paper we describe the application of such processes in modeling the spatial dep
Semiparametric modeling of autonomous nonlinear dynamical systems with application to plant growth
stat.APDebashis Paul, Jie Peng, Prabir Burman
We propose a semiparametric model for autonomous nonlinear dynamical systems and devise an estimation procedure for model fitting. This model incorporates subject-specific effects and can be viewed as a nonlinear semiparametric mixed effects model. We also propose a computationally efficient model selection procedure. We show by simulation studies that the p
Felipe J. Llanes-Estrada, Olga I. Pavlova, Richard Williams
Within pNRQCD we compute the masses of spin-averaged triply heavy baryons using the now-available NNLO pNRQCD potentials and three-body variational approach. We focus in particular on the role of the purely three-body interaction in perturbation theory. This we find to be reasonably small and of the order 25 MeV Our prediction for the Omega_ccc baryon mass i
Kalpana Bora
LBNE (Longbaseline Neutrino Oscillation Experiments) provide a powerful experimental setup to study sensitivities and exlcusion limits in neutrino oscillation parameter space. A longbaseline experiment is being planned, at USA, from FNAL (Fermilab National Accelerator Laboratory) to an underground laboratory at Homestake in South Dakota, at an angle of 5.84
Failed Gamma-Ray Bursts: Thermal UV/Soft X-ray Emission Accompanied by Peculiar Afterglows
astro-ph.HEM. Xu, S. Nagataki, Y. -F. Huang, S. -H. Lee
We show that the photospheres of "failed" Gamma-Ray Bursts (GRBs), whose bulk Lorentz factors are much lower than 100, can be outside of internal shocks. The resulting radiation from the photospheres is thermal and bright in UV/Soft X-ray band. The photospheric emission lasts for about one thousand seconds with luminosity about several times 10^46 er
Identified-particle production and spectra with the ALICE detector in pp and Pb-Pb collisions at the LHC
hep-exRoberto Preghenella
Thanks to its unique capabilities the ALICE experiment can measure the production of identified particles and resonances over a wide momentum range both in pp and Pb-Pb collisions at the LHC. In this report, particle-identification detectors and techniques, as well as achieved performance, are shortly reviewed. The current results on hadron transverse moment
Importance of grain boundary Josephson junctions in the electron-doped infinite-layer cuprate superconductor Sr$_{1-x}$La$_x$CuO$_2$
cond-mat.supr-conJochen Tomaschko, Victor Leca, Teresa Selistrovski, Reinhold Kleiner
Grain boundary bicrystal Josephson junctions of the electron-doped infinite-layer superconductor Sr$_{1-x}$La$_x$CuO$_2$ ($x = 0.15$) were grown by pulsed laser deposition. BaTiO$_3$-buffered $24\,^\circ$ [001]-tilt symmetric SrTiO$_3$ bicrystals were used as substrates. We examined both Cooper pair (CP) and quasiparticle (QP) tunneling by electric transport
Joint Relay Selection and Analog Network Coding using Differential Modulation in Two-Way Relay Channels
cs.ITLingyang Song, Hong Guo, Bingli Jiao, Merouane Debbah
In this paper, we consider a general bi-directional relay network with two sources and N relays when neither the source nodes nor the relays know the channel state information (CSI). A joint relay selection and analog network coding using differential modulation (RS-ANC-DM) is proposed. In the proposed scheme, the two sources employ differential modulations
Lingyang Song
In this paper, we propose a relay selection amplify-and-forward (RS-AF) protocol in general bi-directional relay networks with two sources and $N$ relays. In the proposed scheme, the two sources first transmit to all the relays simultaneously, and then a single relay with a minimum sum symbol error rate (SER) will be selected to broadcast the received signal
Takaaki Monnai
We evaluate the relaxation time to equilibrium, and especially show that it is almost independent from the system size for macroscopic isolated quantum systems. It at most polynomially depends on the system size. This estimation holds when the Hamiltonian is non-integrable, the initial deviation of the quantity of interest is of order its spectral norm, and
Md. Nasim
We present the measurement of elliptic flow ($v_{2}$) as a function of transverse momentum ($p_{T}$) for the $ϕ$-meson in Au+Au collisions at $\sqrt{s_{NN}}$ = 7.7, 11.5 and 39 GeV. At low $p_{T}$ $ϕ$-meson $v_{2}$ decreases with decrease in beam energy. The number of constituent quark ($n_{\rm{cq}}$) scaled $v_{2}$ for $ϕ$-meson vs ($m_{T} - m_{0}$)/$n_{\rm
Sarah J. Schmidt, Adam F. Kowalski, Suzanne L. Hawley, Eric J. Hilton
We present the results of a campaign to monitor active M dwarfs using infrared spectroscopy, supplemented with optical photometry and spectroscopy. We detected 16 flares during nearly 50 hours of observations on EV Lac, AD Leo, YZ CMi, and VB8. The three most energetic flares also showed infrared emission, including the first reported detections of Pβ, Pγ, H
Ansgar Reiners, Subhanjoy Mohanty
Angular momentum evolution in low-mass stars is determined by initial conditions during star formation, stellar structure evolution, and the behaviour of stellar magnetic fields. Here we show that the empirical picture of angular momentum evolution arises naturally if rotation is related to magnetic field strength instead of to magnetic flux, and formulate a
Lingyang Song, Yonghui Li, Anpeng Huang, Bingli Jiao
In this paper, we propose an analog network coding scheme with differential modulation (ANC-DM) using amplify-and-forward protocol for bidirectional relay networks when neither the source nodes nor the relay knows the channel state information (CSI). The performance of the proposed ANC-DM scheme is analyzed and a simple asymptotic bit error rate (BER) expres
Jian Li, Diego F. Torres, Shu Zhang, Daniela Hadasch
From the longest monitoring of LS I +61 303 done to date by the Rossi X-ray Timing Explorer (RXTE) we found evidence for the long-sought, years- long modulation in the X-ray emission of the source. The time evolution of the modulated fraction in the orbital lightcurves can be well fitted with a sinusoidal function having a super-orbital period of 1667 days,
Jan Kisyński
Let $\Mmm$ denote the set of $\mm$ matrices with complex entries, and let $\calG(\partial_1,...,\partial_n)$ be an $\mm$ matrix whose entries are partial differential operators on $\Rn$ with constant complex coefficients. It is proved that $\calG(\partial_1,...,\partial_n)\otimes δ$ is the generating distribution of a smooth one-parameter convolution semigro
Anastasiia Anishchenko, Alexander Blumen, Oliver Muelken
We study the dynamics of continuous-time quantum walks (CTQW) on networks with highly degenerate eigenvalue spectra of the corresponding connectivity matrices. In particular, we consider the two cases of a star graph and of a complete graph, both having one highly degenerate eigenvalue, while displaying different topologies. While the CTQW spreading over the
Parikshit Shah, Venkat Chandrasekaran
Statistical models that possess symmetry arise in diverse settings such as random fields associated to geophysical phenomena, exchangeable processes in Bayesian statistics, and cyclostationary processes in engineering. We formalize the notion of a symmetric model via group invariance. We propose projection onto a group fixed point subspace as a fundamental w
Shijun Lei
We present a new Monte Carlo algorithm applying a history-driven mechanism for the calculation of the density of states for classical statistical models. The new method is as efficient as the Wang-Landau method in sampling through the energy range. With the new method, detailed balance is also naturally satisfied in limit and the estimated density of state c
Spectral transformations in the regime of pulse self-trapping in a nonlinear photonic crystal
physics.opticsDenis Novitsky
We consider interaction of a femtosecond light pulse with a one-dimensional photonic crystal with relaxing cubic nonlinearity in the regime of self-trapping. By use of numerical simulations, it is shown that, under certain conditions, the spectra of reflected and transmitted light possess the properties of narrow-band (quasi-monochromatic) or wide-band (cont
Renormalization Group Analysis of Lattice Theories and Improved Lattice Action. II -- four-dimensional non-abelian SU(N) gauge model
hep-latY. Iwasaki
A new block spin renormalization group transformation for SU(N) gauge models is proposed near the non-trivial fixed point in perturbation theory and thereby the expectation values of various Wilson loops on the renormalized trajectory near the fixed point are explicitly obtained. An improved action is obtained as in a preceding paper and a criterion for the
Design of Image Cryptosystem by Simultaneous VQ-Compression and Shuffling of Codebook and Index Matrix
cs.CRArup Kumar Pal, G. P. Biswas, S. Mukhopadhyay
The popularity of Internet usage although increases exponentially, it is incapable of providing the security for exchange of confidential data between the users. As a result, several cryptosystems for encryption of data and images have been developed for secured transmission over Internet. In this work, a scheme for Image encryption/decryption based on Vecto
Upper critical fields and two-band superconductivity in Sr1-xEux(Fe0.89Co0.11)2As2 (x=0.203 and 0.463)
cond-mat.supr-conRongwei Hu, Eun Deok Mun, M. M. Altarawneh, C. H. Mielke
The upper critical fields, Hc2 of single crystals of Sr1-xEux(Fe0.89Co0.11)2As2(x=0.203 and 0.463) were determined by radio frequency penetration depth measurements in pulsed magnetic fields. Hc2 approaches the Pauli limiting field but shows an upward curvature with an enhancement from the orbital limited field as inferred from Werthamer-Helfand-Hohenberg th
M. V. Medvedev, I. A. Nekrasov, M. V. Sadovskii
We present results of LDA calculations (band structure, densities of states, Fermi surfaces) for possible iron based superconductor BaFe2Se3 (Ba123) in normal (paramagnetic) phase. Results are briefly compared with similar data on prototype BaFe2As2 and (K,Cs)Fe2Se2 superconductors. Without doping this system is antiferromagnetic with T_N^{exp}~250K and rath
Yongseok Oh
The low mass of the $Λ(1405)$ hyperon with $j^P = 1/2^-$, which is higher than the ground state $Λ(1116)$ mass by 290 MeV, is difficult to understand in quark models. We analyze the hyperon spectrum in the bound state approach of the Skyrme model that successfully describes both the $Λ(1116)$ and the $Λ(1405)$. This model predicts that several hyperon resona
Radja Boughezal, Kirill Melnikov, Frank Petriello
We use the known soft and collinear limits of tree- and one-loop scattering amplitudes -- computed over a decade ago -- to explicitly construct a subtraction scheme for next-to-next-to-leading order (NNLO) computations. Our approach combines partitioning of the final-state phase space together with the technique of sector decomposition, following recent sugg
A Universal Gauge for Thermal Conductivity of Silicon Nanowires With Different Cross Sectional Geometries
cond-mat.mes-hallJie Chen, Gang Zhang, Baowen Li
By using molecular dynamics simulations, we study thermal conductivity of silicon nanowires (SiNWs) with different cross sectional geometries. It is found that thermal conductivity decreases monotonically with the increase of surface-to-volume ratio (SVR). More interestingly, a simple universal linear dependence of thermal conductivity on SVR is observed for
Yi-Hsin Liu, J. F. Drake, M. Swisdak
The structure of shocks that form at the exhaust boundaries during collisionless reconnection of anti-parallel fields is studied using particle-in-cell (PIC) simulations and modeling based on the anisotropic magnetohydrodynamic equations. Large-scale PIC simulations of reconnection and companion Riemann simulations of shock development demonstrate that the p
S. Twareque Ali, Mourad E. H. Ismail
We explore in this paper some orthogonal polynomials which are naturally associated to certain families of coherent states, often referred to as nonlinear coherent states in the quantum optics literature. Some examples turn out to be known orthogonal polynomials but in many cases we encounter a general class of new orthogonal polynomials for which we establi
R. Brasser, M. E. Schwamb, P. S. Lykawka, R. S. Gomes
We analyse the origin of three Centaurs with perihelia in the range 15 AU to 30 AU, inclinations above 70 deg and semi-major axes shorter than 100 AU. Based on long-term numerical simulations we conclude that these objects most likely originate from the Oort cloud rather than the Kuiper Belt or Scattered Disc. We estimate that there are currently between 1 a
Roman Glebov
Generalizing a result of Miyakawa, Nozaki, Pogosyan and Rosenberg, we prove that there is a one-to-one correspondence between the set of intersecting antichains in a subset of the lower half of the k-valued n-cube and the set of intersecting antichains in the k-valued (n-1)-cube.
Rongwei Hu, Sheng Ran, S. L. Bud'ko, W. E. Straszheim
We report the single crystal growth of Ca(Fe1-xCox)2As2 (0 <= x <= 0.082) from Sn flux. The temperature-composition phase diagram is mapped out based on the magnetic susceptibility and electrical transport measurements. Phase diagram of Ca(Fe1-xCox)2As2 is qualitatively different from those of Sr and Ba, it could be due to both the charge doping and structur
Philippe De Wilde, Gerard Briscoe
A Multi-Agent System is a distributed system where the agents or nodes perform complex functions that cannot be written down in analytic form. Multi-Agent Systems are highly connected, and the information they contain is mostly stored in the connections. When agents update their state, they take into account the state of the other agents, and they have acces
Zhi Wang, Xiao Hu
Nonlocal entanglement between two quantum dots can be generated through Majorana fermions. The two Majorana fermions at the ends of an one-dimensional topological superconductor form a nonlocal fermion level, coupling to the occupation states of two quantum dots put close to the two ends, and the entire system will come into an entangled state. After introdu
Roman Glebov
In this paper we deal with a Turán-type problem: given a positive integer n and a forbidden graph H, how many edges can there be in a graph on n vertices without a subgraph H? How does a graph look like if it has this extremal edge number? The forbidden graph in this article is a clique-path: a path of length k where each edge is extended to an r-clique, r >
Roman Glebov, Yury Person, Wilma Weps
We study sufficient conditions for Hamiltonian cycles in hypergraphs, and obtain both Turán- and Dirac-type results. While the Turán-type result gives an exact threshold for the appearance of a Hamiltonian cycle in a hypergraph depending only on the extremal number of a certain path, the Dirac-type result yields a sufficient condition relying solely on the m
István Szapudi, Viktor G. Czinner
We present a new approach to cosmological perturbations based on the theory of Lie groups and their representations. After re-deriving the standard covariant formalism from SO(3) considerations, we provide a new expansion of the perturbed Friedmann-Lemaitre-Robertson-Walker (FLRW) metric in terms of irreducible representations of the Lorentz group. The resul
Ilče Georgievski, Alexander Lazovik, Marco Aiello
Hierarchical Task Network (HTN) planning uses task decomposition to plan for an executable sequence of actions as a solution to a problem. In order to reason effectively, an HTN planner needs expressive domain knowledge. For instance, a simplified HTN planning system such as JSHOP2 uses such expressivity and avoids some task interactions due to the increased
Ken Amos, Luciano Canton, Paul Fraser, Steven Karataglidis
The structure of ${}^{17}$C is used to define a nuclear interaction that, when used in a multichannel algebraic scattering theory for the $n+{}^{16}$C system, gives a credible definition of the (compound) excitation spectra. When couplings to the low-lying collective excitations of the ${}^{16}$C-core are taken into account, both sub-threshold and resonant s
Efficient Large Scale Electromagnetics Simulations Using Dynamically Adapted Meshes with the Discontinuous Galerkin Method
physics.comp-phSascha M. Schnepp, Thomas Weiland
A framework for performing dynamic mesh adaptation with the discontinuous Galerkin method (DGM) is presented. Adaptations include modifications of the local mesh step size (h-adaptation) and the local degree of the approximating polynomials (p-adaptation) as well as their combination. The computation of the approximation within locally adapted elements is ba
Combining Lagrangian Decomposition and Excessive Gap Smoothing Technique for Solving Large-Scale Separable Convex Optimization Problems
math.OCTran Dinh Quoc, Carlo Savorgnan, Moritz Diehl
A new algorithm for solving large-scale convex optimization problems with a separable objective function is proposed. The basic idea is to combine three techniques: Lagrangian dual decomposition, excessive gap and smoothing. The main advantage of this algorithm is that it dynamically updates the smoothness parameters which leads to numerically robust perform
Michel De Lara, Eladio Ocana Anaya, Ricardo Oliveros--Ramos, Jorge Tam
The World Summit on Sustainable Development (Johannesburg, 2002) encouraged the application of the ecosystem approach by 2010. However, at the same Summit, the signatory States undertook to restore and exploit their stocks at maximum sustainable yield (MSY), a concept and practice without ecosystemic dimension, since MSY is computed species by species, on th
Jan O. Kleppe
We consider the Hilbert scheme H(d,g) of space curves C with homogeneous ideal I(C):=H_{*}^0(\sI_C) and Rao module M:=H_{*}^1(\sI_C). By taking suitable generizations (deformations to a more general curve) C' of C, we simplify the minimal free resolution of I(C) by e.g. making consecutive free summands (ghost-terms) disappear in a free resolution of I(C&
Ali Kakhbod, Joseph Koo, Demosthenis Teneketzis
We present a simple tatonnement process based on a decomposition method which is simple to implement and achieves the maximal social welfare, under the assumption that the utility function of each [price-taking] individual will be his own private information and need not be known by the designer. At each iteration, very little information needs to be exchang
Tanim Islam
In this paper, a general equation for the evolution of an axisymmetric magnetic field in a Hall plasma is derived, with an integral similar to the Grad-Shafranov equation. Special solutions arising from curvature -- whistler drift modes that propagate along the electron drift as a Burger's shock, and nonlinear periodic and soliton-like solutions to the g
Kenneth A. Marsh, Thomas H. Jarrett
We discuss the optimal detection of point sources from multiwavelength imaging data using an approach, referred to as MDET, which requires no prior knowledge of the source spectrum. MDET may be regarded as a somewhat more general version of the so-called "chi squared" technique. We describe the theoretical basis of the technique, and show examples of
Jarosław Buczyński, J. M. Landsberg
We determine normal forms and ranks of tensors of border rank at most three. We present a differential-geometric analysis of limits of secant planes in a more general context. In particular there are at most four types of points on limiting trisecant planes for cominuscule varieties such as Grassmannians. We also show the singular locus of the first two seca
Yellow supergiants as supernova progenitors: an indication of strong mass loss for red supergiants?
astro-ph.SRCyril Georgy
The increasing observed number of supernova events allows for finding ever more frequently the progenitor star in archive images. In a few cases, the progenitor star is a yellow supergiant star. The estimated position in the Hertzsprung-Russell diagram of these stars is not compatible with the theoretical tracks of classical single star models. According to
James S. Jenkins, Yakiv V. Pavlenko, Oleksiy Ivanyuk, Jose Gallardo
We present new ages and abundance measurements for the pre-main sequence star PZ Tel. PZ Tel was recently found to host a young and low-mass companion. Using FEROS spectra we have measured atomic abundances (e.g. Fe and Li) and chromospheric activity for PZ Tel and used these to obtain metallicity and age estimates for the companion. We find PZ Tel to be a r
Julian Gold
We provide an upper bound on the number of ordered Reidemeister moves required to pass between two diagrams of the same link. This bound is in terms of the number of unordered Reidemeister moves required.
Gerard Ben Arous, Kay Kirkpatrick, Benjamin Schlein
We study the many body quantum evolution of bosonic systems in the mean field limit. The dynamics is known to be well approximated by the Hartree equation. So far, the available results have the form of a law of large numbers. In this paper we go one step further and we show that the fluctuations around the Hartree evolution satisfy a central limit theorem.
The WIRCam Deep Survey I: Counts, colours and mass-functions derived from near-infrared imaging in the CFHTLS deep fields
astro-ph.COR. Bielby, P. Hudelot, H. J. McCracken, O. Ilbert
We present a new near-infrared imaging survey in the four CFHTLS deep fields: the WIRCam Deep Survey (WIRDS). WIRDS comprises extremely deep, high quality (FWHM ~0.6") J, H and K imaging covering a total effective area of 2.1 deg^2 and reaching AB 50% completeness limits of ~24.5. We combine our images with the CFHTLS to create a unique eight-band ugrizJ
Anisotropy of Electrical Transport in Pnictide Superconductors Studied Using Monte Carlo Simulations of the Spin-Fermion Model
cond-mat.str-elShuhua Liang, Gonzalo Alvarez, Cengiz Şen, Adriana Moreo
The undoped three-orbital spin fermion model for the Fe-based superconductors is studied via Monte Carlo techniques in two-dimensional clusters. At low temperatures, the magnetic and one-particle spectral properties are in good agreement with neutron and photoemission experiments. Our most important results are the resistance vs. temperature curves that disp
Early type galaxies have been the predominant morphological class for massive galaxies since only z~1
astro-ph.COFernando Buitrago, Ignacio Trujillo, Christopher J. Conselice, Boris Haeussler
Present-day massive galaxies are composed mostly of early-type objects. It is unknown whether this was also the case at higher redshifts. In a hierarchical assembling scenario the morphological content of the massive population is expected to change with time from disk-like objects in the early Universe to spheroid-like galaxies at present. In this paper we
V. V. Filippov, E. Yu. Mychka
Most of the assertions in the theory of well ordered sets are quite simple. However, one of its central statements, Zermelo's theorem, stands out of this rule, for its well-known proofs are rather complicated. The aim of the current paper is to propose a simple proof of this theorem. Please inform us if you ever encountered such a proof.
Kyle Fox
Let G be a graph embedded on a surface of genus g with b boundary cycles. We describe algorithms to compute multiple types of non-trivial cycles in G, using different techniques depending on whether or not G is an undirected graph. If G is undirected, then we give an algorithm to compute a shortest non-separating cycle in 2^O(g) n log log n time. Similar alg
Anthony G. O'Farrell, Dmitri Zaitsev
An element $g$ of a group is called {\em reversible} if it is conjugate in the group to its inverse. This paper is about reversibles in the group $G$ of formally-invertible pairs of formal power series in two variables, with complex coefficients. The main result is a description of the generic reversible elements of $G$. We list two explicit sequences of rev
Dieter Van den Bleeken
We revisit BPS solutions to classical N=2 low energy effective gauge theories. It is shown that the BPS equations can be solved in full generality by the introduction of a Hesse potential, a symplectic analog of the holomorphic prepotential. We explain how for non-spherically symmetric, non-mutually local solutions, the notion of attractor flow generalizes t
Monica Guica
We consider null warped AdS(3) solutions of three-dimensional gravity coupled to a massive vector field. We isolate a certain set of non-propagating solutions to the equations of motion, which we argue are the ones relevant for understanding the stress tensor sector of the dual field theory. We construct a map from these modes to solutions of three-dimension
Carlo Giocoli, Giuseppe Tormen, Ravi K. Sheth
We develop a simple model for estimating the mass growth histories of dark matter halos. The model is based on a fit to the formation time distribution, where formation is defined as the earliest time that the main branch of the merger tree contains a fraction f of the final mass M . Our analysis exploits the fact that the median formation time as a function
Emma Beynon, Marco Baldi, David J. Bacon, Kazuya Koyama
We present non-linear weak lensing predictions for coupled dark energy models using the CoDECS simulations. We calculate the shear correlation function and error covariance expected for these models, for forthcoming ground-based (such as DES) and space-based (Euclid) weak lensing surveys. We obtain predictions for the discriminatory power of a ground-based s
A. Liam Fitzpatrick, Jared Kaplan
We derive a simple relation between the Mellin amplitude for AdS/CFT correlation functions and the bulk S-Matrix in the flat spacetime limit, proving a conjecture of Penedones. As a consequence of the Operator Product Expansion, the Mellin amplitude for any unitary CFT must be a meromorphic function with simple poles on the real axis. This provides a powerfu
R. J. Sewell, M. Koschorreck, M. Napolitano, B. Dubost
We report the generation of spin squeezing and entanglement in a magnetically-sensitive atomic ensemble, and entanglement-enhanced field measurements with this system. A maximal Raman coherence is prepared in an ensemble of 8.5x10^5 laser-cooled Rb-87 atoms in the f=1 hyperfine ground state, and the collective spin is squeezed by synthesized optical quantum
Accelerated Orbital Expansion And Secular Spin Down of the Accreting Millisecond Pulsar SAX J1808.4-3658
astro-ph.HEA. Patruno, P. Bult, A. Gopakumar, J. M. Hartman
The accreting millisecond pulsar SAX J1808.4-3658 has shown a peculiar orbital evolution in the past with an orbital expansion much faster than expected from standard binary evolutionary scenarios. Previous limits on the pulsar spin frequency derivative during transient accretion outbursts were smaller than predicted by standard magnetic accretion torque the
Yusuke Nishida
Whether the Efimov effect is possible, in principle, for p-wave or higher partial-wave interactions is a fundamental question. Recently, there has been a claim that three nonrelativistic particles with resonant p-wave interactions exhibit the Efimov effect. We point out that the assumed p-wave scattering amplitude inevitably causes a negative probability. Th
Francisco del Aguila, Alberto Aparici, Subhaditya Bhattacharya, Arcadi Santamaria
The minimal Standard Model extension with the Weinberg operator does accommodate the observed neutrino masses and mixing, but predicts a neutrinoless double beta ($0νββ$) decay rate proportional to the effective electron neutrino mass, which can be then arbitrarily small within present experimental limits. However, in general $0νββ$ decay can have an indepen
Man-Fung Cheung, Charles B. Chiu
In a recent paper, we have evaluated the $gg\rightarrow gg$ scattering amplitude in the presence of classical color field generated by the colliding protons in the leading order approximation within the pQCD. In this work, we show that this amplitude can be resumed to obtain the classical color field modified $gg \rightarrow gg$ elastic scattering amplitude.
Sorin Popa, Stefaan Vaes
We prove that for any free ergodic probability measure preserving action \F_n \actson (X,μ) of a free group on n generators \F_n, 2 \leq n \leq \infty, the associated group measure space II_1 factor $L^\infty(X) \rtimes \F_n$ has L^\infty(X) as its unique Cartan subalgebra, up to unitary conjugacy. We deduce that group measure space II_1 factors arising from
Christopher J. Wood, Jacob D. Biamonte, David G. Cory
We describe a graphical calculus for completely positive maps and in doing so review the theory of open quantum systems and other fundamental primitives of quantum information theory using the language of tensor networks. In particular we demonstrate the construction of tensor networks to pictographically represent the Liouville-superoperator, Choi-matrix, p
A. N. Rozanov, M. I. Vysotsky
LHCb collaboration measured CPV at the level of one percent in the difference of assymetries in $D^0(\bar D^0)\to π^+ π^-, K^+ K^-$ decays. If confirmed on a larger statistics and final systematics this would mean New Physics manifestation. The fourth quark-lepton generation can be responsible for the observed effect.
APDs as Single-Photon Detectors for Visible and Near-Infrared Wavelenghts down to Hz Rates
physics.ins-detR. Jöhren, R. Berendes, W. Buglak, D. Hampf
For the SPECTRAP experiment at GSI, Germany, detectors with Single-Photon counting capability in the visible and near-infrared regime are required. For the wavelength region up to 1100 nm we investigate the performance of 2x2 mm^2 avalanche photo diodes (APDs) of type S0223 manufactured by Radiation Monitoring Devices. To minimize thermal noise, the APDs are
Man-Fung Cheung, Charles B. Chiu
We present a formalism for gluon-gluon elastic scattering in the presence of the classical color field of the protons in high energy collision. The classical field is obtained by solving the classical Yang-Mills equation in the covariant gauge and treated as a prescribed background for the quantum gluons involved in the scattering process. The interaction be
Christopher Beresford Powell
We report the results on heavy quarkonium production in p+p and Au+Au collisions at midrapidity via the dielectron decay channel at sqrt(s_NN) = 200 GeV from the STAR experiment at RHIC. Results on the J/psi p_T spectra in p+p collisions are presented for 2 < p_T < 10 GeV/c. The B-meson feed-down contribution to the inclusive J/psi yield has been obtained us
Zhiping Li, Xin Li
Building on the principles of quantum electrodynamics and special relativity, we develop a semi-classical QED theory of gravitation. The experiment model for theoretical analysis is the "hyperfine splitting" of the ground energy state of hydrogen atoms. As the verification and validation by Newton's final experiment, Newton's gravity constant
Ellie Nalson, Adam J. Christopherson, Ian Huston, Karim A. Malik
How much does the curvature perturbation change after it leaves the horizon, and when should one evaluate the power spectrum? To answer these questions we study single field inflation models numerically, and compare the evolution of different curvature perturbations from horizon crossing to the end of inflation. In particular we calculate the number of efold
C. R. Das, Joao Pulido
Neutrino non-standard interactions (NSI), previously introduced for the sun, are studied in the supernova context. For normal hierarchy the probability for electron neutrinos and antineutrinos at low energy ($E\lesssim 0.8-0.9 MeV$) is substantially increased with respect to the non-NSI case and joins its value for inverse hierarchy which is constant with en
Efficient Discovery of Association Rules and Frequent Itemsets through Sampling with Tight Performance Guarantees
cs.DSMatteo Riondato, Eli Upfal
The tasks of extracting (top-$K$) Frequent Itemsets (FI's) and Association Rules (AR's) are fundamental primitives in data mining and database applications. Exact algorithms for these problems exist and are widely used, but their running time is hindered by the need of scanning the entire dataset, possibly multiple times. High quality approximations
Complete characterisation of the azimuthal and radial indices of light fields carrying orbital angular momentum
physics.opticsMichael Mazilu, Areti Mourka, Tom Vettenburg, Kishan Dholakia
The direct determination of the complete transversal state of an electromagnetic field and accompanying mode indices is essential for the proper quantification of all light-matter interactions. In particular light fields with cylindrical symmetry such as Laguerre-Gaussian beams can possess orbital angular momentum, central to a wide range of emergent applica
Vladimir A. Zyuzin
In this paper we propose a model of the fractional quantum Hall effect within conventional one-dimensional bosonization. It is shown that in this formalism the resulting bosonized fermion operator corresponding to momenta of Landau gauge wave function is effectively two-dimensional. At special filling factors the bulk gets gapped, and the theory is described
Dario Martelli, James Sparks
We present the gravity dual to a class of three-dimensional N=2 supersymmetric gauge theories on a biaxially squashed three-sphere, with a non-trivial background gauge field. This is described by a 1/2 BPS Euclidean solution of four-dimensional N=2 gauged supergravity, consisting of a Taub-NUT-AdS metric with a non-trivial instanton for the graviphoton field
Armen Sedrakian
I discuss the structure and composition of massive (two solar-mass) neutron stars containing hypernuclear and deconfined quark matter in color superconducting states. Stable configurations featuring such matter are obtained if the equation of state of hadronic matter is stiff above the saturation density, the transition to quark matter takes place at a few t
Krzysztof Kutak, Krzysztof Golec-Biernat, Stanislaw Jadach, Maciej Skrzypek
Motivated by the regime of QCD explored nowadays at LHC, where both the total energy of collision and momenta transfers are high, we investigate evolution equations of high energy factorization. In order to study such effects like parton saturation in final states one is inevitably led to investigate how to combine physics of the BK and CCFM evolution equati
Jack Spielberg
In this paper we describe the C*-algebras associated to the Baumslag-Solitar groups with the ordering defined by the usual presentations. These are Morita equivalent to the crossed product C*-algebras obtained by letting the group act on its directed boundary. We use the method of categories of paths to define the algebras, and to deduce the presentation by
Nicholas Arcolano, Patrick J. Wolfe
Covariance matrix estimates are an essential part of many signal processing algorithms, and are often used to determine a low-dimensional principal subspace via their spectral decomposition. However, exact eigenanalysis is computationally intractable for sufficiently high-dimensional matrices, and in the case of small sample sizes, sample eigenvalues and eig
Jack Spielberg
In this paper we describe a new method of defining C*-algebras from oriented combinatorial data, thereby generalizing the constructions of algebras from directed graphs, higher-rank graphs, and ordered groups. We show that only the most elementary notions of concatenation and cancellation of paths are required to define versions of Cuntz-Krieger and Toeplitz
Giovanni Viglietta
Mastermind is a popular board game released in 1971, where a codemaker chooses a secret pattern of colored pegs, and a codebreaker has to guess it in several trials. After each attempt, the codebreaker gets a response from the codemaker containing some information on the number of correctly guessed pegs. The search space is thus reduced at each turn, and the
K. T. Osman, W. H. Matthaeus, M. Wan, A. F. Rappazzo
Evidence for inhomogeneous heating in the interplanetary plasma near current sheets dynamically generated by magnetohydrodynamic (MHD) turbulence is obtained using measurements from the ACE spacecraft. These coherent structures only constitute 19% of the data, but contribute 50% of the total plasma internal energy. Intermittent heating manifests as elevation