total 203221took 0.12s

Very High Energy gamma-ray emission from RBS 0970Apr 14 2014In this letter I report the Fermi Large Area Telescope (LAT) detection of Very High Energy (VHE; E>100 GeV) gamma-ray emission from the BL Lac object RBS 0970. 5.3 years of LAT observations revealed the presence of 3 VHE photon events within 0.1 degrees ... More

On the prospects of cross-calibrating the Cherenkov Telescope Array with an airborne calibration platformNov 04 2017Recent advances in unmanned aerial vehicle (UAV) technology have made UAVs an attractive possibility as an airborne calibration platform for astronomical facilities. This is especially true for arrays of telescopes spread over a large area such as the ... More

Locating the gamma-ray emission region of the flat spectrum radio quasar PKS 1510-089Jan 31 2013I present a study of the high-energy gamma-ray properties of the flat spectrum radio quasar, PKS 1510-089, based on 3.75 years of observations with the Large Area Telescope (LAT) detector on-board the Fermi gamma-ray Space Telescope. Throughout the observing ... More

Regular Polyhedra of Index Two, IINov 12 2010A polyhedron in Euclidean 3-space is called a regular polyhedron of index 2 if it is combinatorially regular and its geometric symmetry group has index 2 in its combinatorial automorphism group; thus its automorphism group is flag-transitive but its symmetry ... More

On the 2-linearity of the free groupJun 21 2016We construct an action of the free group $F_n$ on the homotopy category of projective modules over a finite dimensional zigzag algebra. The main theorem in the paper is that this action is faithful. We describe the relationship between homotopy classes ... More

Transformation Electromagnetics Devices Based on Printed-Circuit Tensor Impedance SurfacesJul 12 2013A method for designing transformation electromagnetics devices using tensor impedance surfaces (TISs) is presented. The method is first applied to idealized tensor impedance boundary conditions (TIBCs), and later to printed-circuit tensor impedance surfaces ... More

A Littlewood-Richardson rule for the MacDonald inner product and bimodules over wreath productsSep 18 2013We prove a Littlewood-Richardson type formula for $(s_{\lambda/\mu},s_{\nu/\kappa})_{t^k,t}$, the pairing of two skew Schur functions in the MacDonald inner product at $q = t^k$ for positive integers $k$. This pairing counts graded decomposition numbers ... More

Nonholonomic Hamilton-Jacobi equation and IntegrabilityJun 18 2009Dec 18 2009We discuss an extension of the Hamilton-Jacobi theory to nonholonomic mechanics with a particular interest in its application to exactly integrating the equations of motion. We give an intrinsic proof of a nonholonomic analogue of the Hamilton--Jacobi ... More

Pulsar spins from an instability in the accretion shock of supernovaeNov 21 2006Rotation-powered radio pulsars are born with inferred initial rotation periods of order 300 ms (some as short as 20 ms) in core-collapse supernovae. In the traditional picture, this fast rotation is the result of conservation of angular momentum during ... More

Strategies and Networks for State-Dependent Quantum CloningDec 15 1998State-dependent cloning machines that have so far been considered either deterministically copy a set of states approximately, or probablistically copy them exactly. In considering the case of two equiprobable pure states, we derive the maximum global ... More

Quantum State Separation, Unambiguous Discrimination and Exact CloningAug 11 1998Unambiguous discrimination and exact cloning reduce the square-overlap between quantum states, exemplifying the more general type of procedure we term state separation. We obtain the maximum probability with which two equiprobable quantum states can be ... More

High energy gamma-ray properties of the FR I radio galaxy NGC 1275Jan 13 2011We report on our study of the high-energy $\gamma-$ray emission from the FR I radio galaxy NGC 1275, based on two years of observations with the Fermi-LAT detector. Previous Fermi studies of NGC 1275 had found evidence for spectral and flux variability ... More

Regular Polyhedra of Index Two, IMay 26 2010A polyhedron in Euclidean 3-space is called a regular polyhedron of index 2 if it is combinatorially regular but "fails geometric regularity by a factor of 2"; its combinatorial automorphism group is flag-transitive but its geometric symmetry group has ... More

The Spherical Accretion Shock Instability in the Linear RegimeJul 07 2005We use time-dependent, axisymmetric, hydrodynamic simulations to study the linear stability of the stalled, spherical accretion shock that arises in the post-bounce phase of core-collapse supernovae. We show that this accretion shock is stable to radial ... More

Discovery of gamma-ray emission from the Broad Line Radio Galaxy Pictor ADec 29 2011We report the discovery of high-energy \gamma-ray emission from the Broad Line Radio Galaxy (BLRG) Pictor A with a significance of ~5.8\sigma (TS=33.4), based on three years of observations with the Fermi Large Area Telescope (LAT) detector. The three-year ... More

Scalable Extended Dynamic Mode Decomposition using Random Kernel ApproximationOct 27 2017The Koopman operator is a linear, infinite-dimensional operator that governs the dynamics of system observables; Extended Dynamic Mode Decomposition (EDMD) is a data-driven method for approximating the Koopman operator using functions (features) of the ... More

Malmquist Bias and the Distance to the Virgo ClusterApr 18 1997This paper investigates the impact of Malmquist bias on the distance to the Virgo cluster determined by the H_0 Key Project using M100, and consequently on the derived value of H_0. Malmquist bias is a volume-induced statistical effect which causes the ... More

The ANTARES Neutrino Telescope: status and first resultsAug 07 2009Completed in May 2008, the ANTARES neutrino telescope is located in the Mediterranean Sea, 40 km off the coast of Toulon, at a depth of about 2500 m. Consisting of 12 detector lines housing nearly 900 optical modules, the ANTARES telescope is currently ... More

An extension to the theory of controlled Lagrangians using the Helmholtz conditionsNov 19 2017The Helmholtz conditions are necessary and sufficient conditions for a system of second order differential equations to be variational, that is, equivalent to a system of Euler-Lagrange equations for a regular Lagrangian. On the other hand, matching conditions ... More

Optimal Control of Underactuated Nonholonomic Mechanical SystemsOct 01 2005In this paper we use an affine connection formulation to study an optimal control problem for a class of nonholonomic, under-actuated mechanical systems. In particular, we aim at minimizing the norm-squared of the control input to move the system from ... More

Hill's Equation with Random Forcing Parameters: Determination of Growth Rates through Random MatricesFeb 04 2010This paper derives expressions for the growth rates for the random 2 x 2 matrices that result from solutions to the random Hill's equation. The parameters that appear in Hill's equation include the forcing strength and oscillation frequency. The development ... More

Hill's Equation with Random Forcing Parameters: The Limit of Delta Function BarriersJun 10 2009This paper considers random Hill's equations in the limit where the periodic forcing function becomes a Dirac delta function. For this class of equations, the forcing strength $q_k$, the oscillation frequency $\af_k$, and the period are allowed to vary ... More

Complete r-partite graphs determined by their domination polynomialMar 24 2013Apr 02 2013The domination polynomial of a graph is the polynomial whose coefficients count the number of dominating sets of each cardinality. A recent question asks which graphs are uniquely determined (up to isomorphism) by their domination polynomial. In this ... More

Probing Black Hole Microstate Evolution with Networks and Random WalksDec 21 2018We model black hole microstates and quantum tunneling transitions between them with networks and simulate their time evolution using well-established tools in network theory. In particular, we consider two models based on Bena-Warner three-charge multi-centered ... More

The friction of a mesh-like super-hydrophobic surfaceNov 16 2009When a liquid droplet is located above a super-hydrophobic surface, it only barely touches the solid portion of the surface, and therefore slides very easily on it. More generally, super-hydrophobic surfaces have been shown to lead to significant reduction ... More

Development and Initial Validation of a Scale to Measure Instructors' Attitudes toward Concept-Based Teaching of Introductory Statistics in the Health and Behavioral SciencesJul 19 2010Despite more than a decade of reform efforts, students continue to experience difficulty understanding and applying statistical concepts. The predominant focus of reform has been on content, pedagogy, technology and assessment, with little attention to ... More

Localizing the Angular Momentum of Linear GravityOct 02 2012In a previous article [Phys. Rev. D 82 104040 (2010)], we derived an energy-momentum tensor for linear gravity that exhibited positive energy density and causal energy flux. Here we extend this framework by localizing the angular momentum of the linearized ... More

The physical significance of the Babak-Grishchuk gravitational energy-momentum tensorJul 01 2008Jul 15 2008We examine the claim of Babak and Grishchuk [1] to have solved the problem of localising the energy and momentum of the gravitational field. After summarising Grishchuk's flat-space formulation of gravity, we demonstrate its equivalence to General Relativity ... More

Quantum coarse-grained entropy and thermodynamicsJul 31 2017Jan 15 2019We extend classical coarse-grained entropy, commonly used in many branches of physics, to the quantum realm. We find two coarse-grainings, one using measurements of local particle numbers and then total energy, and the second using local energy measurements, ... More

Anything can happen, but only given half a chance: a quantum bound on large fluctuations away from equilibriumJun 23 2018We ask to what extent an isolated quantum system can eventually "contract" to be contained within a given Hilbert subspace. We do this by starting with an initial random state, considering the probability that all the particles will be measured in a fixed ... More

Trees, Forests, and Stationary States of Quantum Lindblad SystemsOct 26 2018In this paper, we study the stationary orbits of quantum Lindblad systems. We show that they can be characterized in terms of trees and forests on a directed graph with edge weights that depend on the Lindblad operators and the eigenbasis of the density ... More

Positioning system of the ANTARES Neutrino TelescopeAug 06 2009Completed in May 2008, the ANTARES neutrino telescope is located 40 km off the coast of Toulon, at a depth of about 2500 m. The telescope consists of 12 detect or lines housing a total of 884 optical modules. Each line is anchored to the seabed and pulled ... More

The iterated auxiliary particle filterNov 19 2015Jun 15 2016We present an offline, iterated particle filter to facilitate statistical inference in general state space hidden Markov models. Given a model and a sequence of observations, the associated marginal likelihood L is central to likelihood-based inference ... More

Electroweak Phase Transition in Two Higgs Doublet ModelsSep 03 1996Aug 23 2007We reexamine the strength of the first order phase transition in the electroweak theory supplemented by an extra Higgs doublet. The finite-temperature effective potential, $V_{eff}$, is computed to one-loop order, including the summation of ring diagrams, ... More

Baryonic Collapse within Dark Matter Halos and the Formation of Gaseous Galactic DisksSep 12 2006This paper constructs an analytic framework for calculating the assembly of galactic disks from the collapse of gas within dark matter halos, with the goal of determining the surface density profiles. Gas parcels (baryons) fall through the potentials ... More

Evolution of Planetary Orbits with Stellar Mass Loss and Tidal DissipationOct 09 2013Intermediate mass stars and stellar remnants often host planets, and these dynamical systems evolve because of mass loss and tides. This paper considers the combined action of stellar mass loss and tidal dissipation on planetary orbits in order to determine ... More

Flag-based Control of Orbit Dynamics in Quantum Lindblad SystemsFeb 20 2016In this paper, we demonstrate that the dynamics of an $n$-dimensional Lindblad control system can be separated into its inter- and intra-orbit dynamics when there is fast controllability. This can be viewed as a control system on the simplex of density ... More

An objective classification of Saturn cloud features from Cassini ISS imagesSep 25 2017A clustering algorithm is applied to Cassini Imaging Science Subsystem continuum and methane band images of Saturns northern hemisphere to objectively classify regional albedo features and aid in their dynamical interpretation. The procedure is based ... More

Colwell's Castle Defence: A Custom Game Using Dynamic Difficulty Adjustment to Increase Player EnjoymentJun 12 2018Dynamic Difficulty Adjustment (DDA) is a mechanism used in video games that automatically tailors the individual gaming experience to match an appropriate difficulty setting. This is generally achieved by removing pre-defined difficulty tiers such as ... More

Computing automorphism groups of shifts using atypical equivalence classesMay 11 2015Feb 01 2017We study the automorphism group of an infinite minimal shift $(X,\sigma)$ such that the complexity difference function, $p(n+1)-p(n)$, is bounded. We give some new bounds on $\mbox{Aut}(X,\sigma)/\langle \sigma \rangle$ and also study the one-sided case. ... More

Viscous Marangoni propulsionDec 05 2012Marangoni propulsion is a form of locomotion wherein an asymmetric release of surfactant by a body located at the surface of a liquid leads to its directed motion. We present in this paper a mathematical model for Marangoni propulsion in the viscous regime. ... More

Geometric transition in friction for flow over a bubble mattressDec 10 2008Laminar flow over a bubble mattress is expected to experience a significant reduction in friction since the individual surfaces of the bubbles are shear-free. However, if the bubbles are sufficiently curved, their protrusion into the fluid and along the ... More

Hydrodynamic friction of fakir-like super-hydrophobic surfacesMay 20 2010A fluid droplet located on a super-hydrophobic surface makes contact with the surface only at small isolated regions, and is mostly in contact with the surrounding air. As a result, a fluid in motion near such a surface experiences very low friction, ... More

Bootstrapping gravity: a consistent approach to energy-momentum self-couplingJun 04 2009Oct 14 2009It is generally believed that coupling the graviton (a classical Fierz-Pauli massless spin-2 field) to its own energy-momentum tensor successfully recreates the dynamics of the Einstein field equations order by order; however the validity of this idea ... More

The central engines of radio-quiet quasarsMay 13 1998Two rival hypotheses have been proposed for the origin of the compact radio flux observed in radio-quiet quasars (RQQs). It has been suggested that the radio emission in these objects, typically some two or three orders of magnitude less powerful than ... More

Wiring Switches to Light BulbsJan 25 2011Given n buttons and n bulbs so that the ith button toggles the ith bulb and at most two other bulbs, we compute the sharp lower bound on the number of bulbs that can be lit regardless of the action of the buttons.

Khovanov's Heisenberg category, moments in free probability, and shifted symmetric functionsOct 14 2016We establish an isomorphism between the center of the Heisenberg category defined by Khovanov and the algebra $\Lambda^*$ of shifted symmetric functions defined by Okounkov-Olshanski. We give a graphical description of the shifted power and Schur bases ... More

Discrete Hamilton-Jacobi TheoryNov 11 2009Jun 08 2011We develop a discrete analogue of Hamilton-Jacobi theory in the framework of discrete Hamiltonian mechanics. The resulting discrete Hamilton-Jacobi equation is discrete only in time. We describe a discrete analogue of Jacobi's solution and also prove ... More

A Review on Recommendation Systems: Context-aware to Social-basedNov 28 2018The number of Internet users had grown rapidly enticing companies and cooperations to make full use of recommendation infrastructures. Consequently, online advertisement companies emerged to aid us in the presence of numerous items and users. Even as ... More

Fermi-LAT high $z$ AGN and the Extragalactic Background LightMay 31 2017Observations of distant gamma-ray sources are hindered by the presence of the extragalactic background light (EBL). In order to understand the physical processes that result in the observed spectrum of sources, it is imperative that a good understanding ... More

Annular Khovanov-Lee homology, braids, and cobordismsDec 18 2016We prove that the Khovanov-Lee complex of an oriented link, L, in a thickened annulus, A x I, has the structure of a bifiltered complex whose filtered chain homotopy type is an invariant of the isotopy class of L in A x I. Using ideas of Ozsvath-Stipsicz-Szabo ... More

Gamma-ray emission from high Galactic latitude globular clustersAug 11 2018Aug 14 2018We analyse 8 years of PASS 8 Fermi-LAT data, in the 60 MeV - 300 GeV energy range, from 30 high Galactic latitude globular clusters. Six of these globular clusters are detected with a TS > 25, with NGC 6254 being detected as gamma-ray bright for the first ... More

Dynamics of Symplectic SubVolumesSep 09 2007In this paper we will explore fundamental constraints on the evolution of certain symplectic subvolumes possessed by any Hamiltonian phase space. This research has direct application to optimal control and control of conservative mechanical systems. We ... More

Very high energy $γ$-ray emission from RBS 0679Oct 07 2014In this paper we report the \textit{Fermi} Large Area Telescope (LAT) detection of Very High Energy (VHE; $E_{\gamma}>100$ GeV) $\gamma$-ray emission from the BL Lac object RBS 0679. $5.3$ years of LAT observations revealed the presence of three VHE photon ... More

$γ$-ray observations of extraterrestrial neutrino track event positionsMay 05 2015In this paper we report the results of a $\gamma$-ray study of IceCube's extraterrestrial neutrino candidates detected as track-like events. Using 70 months of Fermi-LAT observations, a likelihood analysis of all $1-300$ GeV photons within 5 degrees of ... More

Localising the gamma-ray emission region during the June 2014 outburst of 3C 454.3Jan 26 2016In May - July 2014, the flat spectrum radio quasar 3C 454.3 exhibited strong flaring behaviour. Observations with the Large Area Telescope detector on-board the Fermi Gamma-ray Space Telescope captured the $\gamma$-ray flux at energies 0.1 $\leq E_{\gamma}\leq$ ... More

Icosahedral Skeletal Polyhedra Realizing Petrie Relatives of Gordan's Regular MapOct 07 2012Every regular map on a closed surface gives rise to generally six regular maps, its "Petrie relatives", that are obtained through iteration of the duality and Petrie operations (taking duals and Petrie-duals). It is shown that the skeletal polyhedra in ... More

Annular Khovanov homology and knotted Schur-Weyl representationsMay 17 2015Let L be a link in a thickened annulus. We show that its sutured annular Khovanov homology carries an action of the exterior current algebra of the Lie algebra sl_2. When L is an m-framed n-cable of a knot K in the three-sphere, its sutured annular Khovanov ... More

Particle acceleration and magnetic field amplification in the jets of 4C74.26May 08 2015Jun 07 2015We model the multi-wavelength emission in the southern hotspot of the radio quasar 4C74.26. The synchrotron radio emission is resolved near the shock with the MERLIN radio-interferometer, and the rapid decay of this emission behind the shock is interpreted ... More

Restricted Discrete Invariance and Self-Synchronization For Stable Walking of Bipedal RobotsNov 01 2014Jun 10 2016Models of bipedal locomotion are hybrid, with a continuous component often generated by a Lagrangian plus actuators, and a discrete component where leg transfer takes place. The discrete component typically consists of a locally embedded co-dimension ... More

Development of a culturally-oriented website usability evaluationMar 12 2018As the uni-cultural studies of website usability have matured, the paucity of cross-cultural studies of usability become increasingly apparent. Moving toward these cross-cultural studies will require the development of a new tool to assess website usability ... More

Comparing Spatial Regression to Random Forests for Large Environmental Data SetsDec 26 2018Environmental data may be "large" due to number of records, number of covariates, or both. Random forests has a reputation for good predictive performance when using many covariates with nonlinear relationships, whereas spatial regression, when using ... More

The Large-Scale Distribution and Motions of Older Stars in OrionFeb 05 1998Apr 13 1998We review the current knowledge of the population of `older' stars in the Orion OB1 association, specifically those in subgroups 1a and 1b. We briefly outline the history of the subject and then continue with a summary of the present state of knowledge ... More

Parallel resampling in the particle filterJan 17 2013Jun 11 2015Modern parallel computing devices, such as the graphics processing unit (GPU), have gained significant traction in scientific and statistical computing. They are particularly well-suited to data-parallel algorithms such as the particle filter, or more ... More

A Hyperbolic System in a One-Dimensional NetworkSep 09 2002We study a coupled system of Navier-Stokes equation and the equation of conservation of mass in a one-dimensional network. The system models the blood circulation in arterial networks. A special feature of the system is that the equations are coupled ... More

Effects of Turbulence, Eccentricity Damping, and Migration Rate on the Capture of Planets into Mean Motion ResonanceNov 05 2010Pairs of migrating extrasolar planets often lock into mean motion resonance as they drift inward. This paper studies the convergent migration of giant planets (driven by a circumstellar disk) and determines the probability that they are captured into ... More

Eclipses by a Circumstellar Dust Feature in the Pre-Main Sequence Star KH15DMay 23 2001Jun 08 2001Photometry and spectroscopy of the unique pre-main sequence eclipsing object KH15D in the young cluster NGC 2264 are presented. The orbital period is 48.34 days and both the length (~16 d) and depth (~3 mag) of the eclipse have increased with time. A ... More

Uncertainty Quantification for Airfoil Icing using Polynomial Chaos ExpansionsNov 13 2014The formation and accretion of ice on the leading edge of a wing can be detrimental to airplane performance. Complicating this reality is the fact that even a small amount of uncertainty in the shape of the accreted ice may result in a large amount of ... More

Ubiquity of density slope oscillations in the central regions of galaxy and cluster-sized systemsApr 05 2016One usually thinks of a radial density profile as having a monotonically changing logarithmic slope, such as in NFW or Einasto profiles. However, in two different classes of commonly used systems, this is often not the case. These classes exhibit non-monotonic ... More

A variational problem on Stiefel manifoldsSep 01 2006In their paper on discrete analogues of some classical systems such as the rigid body and the geodesic flow on an ellipsoid, Moser and Veselov introduced their analysis in the general context of flows on Stiefel manifolds. We consider here a general class ... More

Improved Volterra Kernel Methods with Applications to the Visual SystemDec 05 2008Volterra analysis and its variants have long been prominent among methods for modeling multi-input non-linear systems. The product of Volterra analysis, the Volterra kernels, are particularly suited to quantifying intra- and inter-input interactions. ... More

Global consensus Monte CarloJul 24 2018For Bayesian inference with large data sets, it is often convenient or necessary to distribute the data across multiple machines. We consider a likelihood function expressed as a product of terms, each associated with a subset of the data. Inspired by ... More

W-algebras from Heisenberg categoriesJan 03 2015The trace (or zeroth Hochschild homology) of Khovanov's Heisenberg category is identified with a quotient of the algebra W_{1+\infty}. This induces an action of W_{1+\infty} on symmetric functions.

Anytime Monte CarloDec 10 2016Jun 07 2017A Monte Carlo algorithm typically simulates some prescribed number of samples, taking some random real time to complete the computations necessary. This work considers the converse: to impose a real-time budget on the computation, so that the number of ... More

ALMA Observations of the Spatial Distribution of three C$_2$H$_4$O$_2$ Isomers towards Sgr B2(N)Dec 17 2018Dec 21 2018The C$_2$H$_4$O$_2$ isomers have been previously investigated primarily via disparate sets of observations involving single dish and array measurements. The only attempt at using a uniform set of observations was performed with the IRAM 30 m observation ... More

Evolution of Planetary Systems with Time Dependent Stellar Mass LossMar 15 2013Observations indicate that intermediate mass stars, binary stars, and stellar remnants often host planets; a complete explanation of these systems requires an understanding of how planetary orbits evolve as their central stars lose mass. Motivated by ... More

Mean Motion Resonances in Exoplanet Systems: An Investigation Into Nodding BehaviorNov 13 2012Motivated by the large number of extrasolar planetary systems that are near mean motion resonances, this paper explores a related type of dynamical behavior known as "nodding". Here, the resonance angle of a planetary system executes libration (oscillatory ... More

CMB lensing and primordial non-GaussianityMay 28 2009Jun 18 2010We study the effects of gravitational lensing on the estimation of non-Gaussianity from the bispectrum of the cosmic microwave background (CMB) temperature anisotropies. We find that the effect of lensing on the bispectrum may qualitatively be described ... More

Non-Renormalization For Non-Supersymmetric Black HolesFeb 27 2017We analyze large logarithmic corrections to 4D black hole entropy and relate them to the Weyl anomaly. We use duality to show that counter-terms in Einstein-Maxwell theory can be expressed in terms of geometry alone, with no dependence on matter terms. ... More

Formation of Chimneys in Mushy Layers: Experiment and SimulationOct 18 2011In this fluid dyanmics video, we show experimental images and simulations of chimney formation in mushy layers. A directional solidification apparatus was used to freeze 25 wt % aqueous ammonium chloride solutions at controlled rates in a narrow Hele-Shaw ... More

Vector Dark Matter through a Radiative Higgs PortalDec 21 2015May 18 2016We study a model of spin-1 dark matter which interacts with the Standard Model predominantly via exchange of Higgs bosons. We propose an alternative UV completion to the usual Vector Dark Matter Higgs Portal, in which vector-like fermions charged under ... More

Evidence for a black hole in a radio-quiet quasar nucleusJun 17 1996We present the first milli-arcsecond resolution radio images of a radio-quiet quasar, detecting a high brightness temperature core with data from the VLBA. On maps made with lower-frequency data from MERLIN and the VLA jets appear to emanate from the ... More

On the joint analysis of CMB temperature and lensing-reconstruction power spectraAug 01 2013Gravitational lensing provides a significant source of cosmological information in modern CMB parameter analyses. It is measured in both the power spectrum and trispectrum of the temperature fluctuations. These observables are often treated as independent, ... More

The Effect of a Light Sterile Neutrino at NO$ν$A and DUNEApr 10 2018Aug 10 2018Now that the NOvA experiment is approaching two years run time and has released some preliminary data, some constraints for the oscillation parameters can be inferred. Currently the best fits for NOvA are three separate results, the reason they are indistinct ... More

Evaluating the Gamma-Ray Evidence for Self-Annihilating Dark Matter from the Virgo ClusterJul 26 2012Oct 09 2012Based on three years of Fermi Large Area Telescope (LAT) gamma-ray data of the Virgo cluster, evidence for an extended emission associated with dark matter pair annihilation in the b b-bar channel has been reported by Han et al. [1]. After an in depth ... More

Latest results from the IceCube ExperimentDec 07 2010The IceCube Collaboration is currently building the world's largest neutrino telescope at the South Pole to observe high energy neutrinos from a variety of astrophysical sources. In this paper we review the current status of the IceCube experiment, highlighting ... More

A Conjectured Integer Sequence Arising From the Exponential IntegralDec 02 2018Dec 15 2018Let $f_0(z) = \exp(z/(1-z))$, $f_1(z) = \exp(1/(1-z))E_1(1/(1-z))$, where $E_1(x) = \int_x^\infty e^{-t}t^{-1}{\,d}t$. Let $a_n = [z^n]f_0(z)$ and $b_n = [z^n]f_1(z)$ be the corresponding Maclaurin series coefficients. We show that $a_n$ and $b_n$ may ... More

A Model of Blood Flow in a Circulation NetworkOct 26 2002We study a mathematical model of a blood circulation network which is a generalization of the coronary model proposed by Smith, Pullan and Hunter. We prove the existence and uniqueness of the solution to the initial-boundary value problem and discuss ... More

Comparative Analysis of RNA Families Reveals Distinct Repertoires for Each Domain of LifeSep 07 2012The RNA world hypothesis, that RNA genomes and catalysts preceded DNA genomes and genetically-encoded protein catalysts, has been central to models for the early evolution of life on Earth. A key part of such models is continuity between the earliest ... More

Gradient flows in the normal and Kähler metrics and triple bracket generated metriplectic systemsAug 30 2012The dynamics of gradient and Hamiltonian flows with particular application to flows on adjoint orbits of a Lie group and the extension of this setting to flows on a loop group are discussed. Different types of gradient flows that arise from different ... More

Out of equilibrium: understanding cosmological evolution to lower-entropy statesAug 01 2011Despite the importance of the Second Law of Thermodynamics, it is not absolute. Statistical mechanics implies that, given sufficient time, systems near equilibrium will spontaneously fluctuate into lower-entropy states, locally reversing the thermodynamic ... More

Dynamics of merging: Post-merger mixing and relaxation of an Illustris galaxyAug 31 2017Feb 14 2018During the merger of two galaxies, the resulting system undergoes violent relaxation and seeks stable equilibrium. However, the details of this evolution are not fully understood. Using Illustris simulation, we probe two physically related processes, ... More

Diagram automorphisms of quiver varietiesSep 03 2013Sep 08 2014We show that the fixed-point subvariety of a Nakajima quiver variety under a diagram automorphism is a disconnected union of quiver varieties for the `split-quotient quiver' introduced by Reiten and Riedtmann. As a special case, quiver varieties of type ... More

Gamma-rays from SS433: evidence for periodicityMar 01 2019In this paper we present our study of the gamma-ray emission from the microquasar SS433. Integrating over 9 years of Fermi-LAT \textsc{pass8} data, we detect SS433 with a significance of ~13$\sigma$ in the 200 to 500 MeV photon energy range, with evidence ... More

Suppression of Reabsorption via Modulation of LightJul 24 2006Jul 24 2006Reabsorption, the multiple scattering of spontaneously emitted photons in optically thick gases, is a major limitation to efficient optical pumping and laser cooling in ultracold gases. We report mitigation of reabsorption using spatial and frequency ... More

Hidden On-Shell Mediators for the Galactic Center Gamma-Ray ExcessApr 25 2014Aug 28 2014We present simplified models for the galactic center gamma-ray excess where Dirac dark matter annihilates into pairs or triplets of on-shell bosonic mediators to the Standard Model. These annihilation modes allow the dark matter mass to be heavier than ... More

The Detection of Fermi AGN above 100 GeV using Clustering AnalysisJun 23 2015Aug 03 2015The density-based clustering algorithm DBSCAN has been applied to the Fermi Large Area Telescope (LAT) dataset of $ E_{\gamma} \geqslant 100$ GeV events with $\lvert b\rvert>10^{\circ}$, in order to search for new very high energy (VHE) $\gamma$-ray sources. ... More

Receiver Operating Characteristics for a Prototype Quantum Two-Mode Squeezing RadarFeb 28 2019We have built and evaluated a prototype quantum radar, which we call a quantum two-mode squeezing radar (QTMS radar), in the laboratory. It operates solely at microwave frequencies; there is no downconversion from optical frequencies. Because the signal ... More

Model Structural Inference using Local Dynamic OperatorsMar 10 2018Jan 31 2019This paper focuses on the problem of quantifying the effects of model-structure uncertainty in the context of time-evolving dynamical systems. This is motivated by multi-model uncertainty in computer physics simulations: developers often make different ... More

Experimental Demonstration of Optimal Unambiguous State DiscriminationJul 19 2000We present the first full demonstration of unambiguous state discrimination between non-orthogonal quantum states. Using a novel free space interferometer we have realised the optimum quantum measurement scheme for two non-orthogonal states of light, ... More