Results for "William B. McKinnon"

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The Pluto System After New HorizonsDec 15 2017The discovery of Pluto in 1930 presaged the discoveries of both the Kuiper Belt and ice dwarf planets, which are the third class of planets in our solar system. From the 1970s to the 19990s numerous fascinating attributes of the Pluto system were discovered, ... More
Search for the $Θ^+$ pentaquark in the reaction $γd \to p K^- K^+ n$Mar 14 2006May 04 2006A search for the \thp in the reaction $\gamma d \to pK^-K^+n$ was completed using the CLAS detector at Jefferson Lab. A study of the same reaction, published earlier, reported the observation of a narrow \thp resonance. The present experiment, with more ... More
Triton's surface age and impactor population revisited in light of Kuiper Belt fluxes: Evidence for small Kuiper Belt objects and recent geological activityOct 24 1999Neptune's largest satellite, Triton, is one of the most fascinating and enigmatic bodies in the solar system. Among its numerous interesting traits, Triton appears to have far fewer craters than would be expected if its surface was primordial. Here we ... More
Linear-response reflection coefficient of the recorder air-jet amplifierFeb 07 2015Dec 09 2015In a duct-flute such as the recorder, steady-state oscillations are controlled by two parameters, the blowing pressure and the frequency of the acoustic resonator. As in most feedback oscillators, the oscillation amplitude is determined by gain-saturation ... More
Crater Density Predictions for New Horizons flyby target 2014 MU69Dec 23 2018Jan 02 2019In preparation for the Jan 1/2019 encounter between the New Horizons spacecraft and the Kuiper Belt object 2014 MU69, we provide estimates of the expected impact crater surface density on the Kuiper Belt object. Using the observed crater fields on Charon ... More
Counting Rational Points on Ruled VarietiesJul 10 2002In this paper, we prove a general result computing the number of rational points of bounded height on a projective variety $V$ which is covered by lines. The main technical result used to achieve this is an upper bound on the number of rational points ... More
Vojta's Conjecture implies the Batyrev-Manin Conjecture for $K3$ surfacesNov 26 2010Vojta's Conjectures are well known to imply a wide range of results, known and unknown, in arithmetic geometry. In this paper, we add to the list by proving that they imply that rational points tend to repel each other on algebraic varieties with nonnegative ... More
A conjecture on rational approximations to rational pointsApr 14 2005Apr 04 2006In this paper, we examine how well a rational point P on an algebraic variety X can be approximated by other rational points. We conjecture that if P lies on a rational curve, then the best approximations to P on X can be chosen to lie along a rational ... More
Counting Rational Points on K3 SurfacesMar 02 1999Mar 04 1999For any algebraic variety $V$ defined over a number field $k$, and ample height function $H$ on $V$, one can define the counting function $N_V(B) = #{P\in V(k) \mid H(P)\leq B}$. In this paper, we calculate the counting function for Kummer surfaces $V$ ... More
Mean radius and shape of Pluto and Charon from New Horizons imagesMar 02 2016Jun 22 2016Approach images taken by the LORRI imaging system during the New Horizons spacecraft encounter have been used to determine the mean radii and shapes of Pluto and Charon. The primary observations are limb locations derived using three independent approaches. ... More
Photoproduction of $Λ$ and $Σ^0$ hyperons using linearly polarized photonsMar 21 2016Jun 14 2016Background: Measurements of polarization observables for the reactions $\vec{\gamma} p \rightarrow K^+ \Lambda$ and $\vec{\gamma} p \rightarrow K^+ \Sigma^0$ have been performed. This is part of a programme of measurements designed to study the spectrum ... More
New Horizons: Anticipated Scientific Investigations at the Pluto SystemSep 26 2007The New Horizons spacecraft will achieve a wide range of measurement objectives at the Pluto system, including color and panchromatic maps, 1.25-2.50 micron spectral images for studying surface compositions, and measurements of Pluto's atmosphere (temperatures, ... More
The LEAP of Pulsars in the Milky WayDec 24 2010The location of objects on the celestial sphere is a fundamental measurement in astronomy, and the distribution of these objects within the Milky Way is important for understanding their evolution as well as the large scale structure of the Galaxy. Here, ... More
Directional Statistics for Polarization Observations of Individual Pulses from Radio PulsarsDec 24 2010Radio polarimetry is a three-dimensional statistical problem. The three-dimensional aspect of the problem arises from the Stokes parameters Q, U, and V, which completely describe the polarization of electromagnetic radiation and conceptually define the ... More
The Analytical Solution to the Temporal Broadening of a Gaussian-Shaped Radio Pulse by Multipath Scattering from a Thin Screen in the Interstellar MediumApr 26 2014The radio pulse from a pulsar can be temporally broadened by multipath scattering in the interstellar medium and by instrumental effects within the radio telescope. The observed pulse shape is a convolution of the intrinsic one with the impulse responses ... More
Ideals of degree one contribute most of the heightJun 07 2011Let $k$ be a number field, $f(x)\in k[x]$ a polynomial over $k$ with $f(0)\neq 0$, and $\O_{k,S}^*$ the group of $S$-units of $k$, where $S$ is an appropriate finite set of places of $k$. In this note, we prove that outside of some natural exceptional ... More
Voltage Induced Hidden Symmetry and Photon Entanglement Generation in a Single, Site-Selected Quantum DotJun 07 2007Present proposals for the realisation of entangled photon pair sources using the radiative decay of the biexciton in semiconductor quantum dots are limited by the need to enforce degeneracy of the two intermediate, single exciton states. We show how this ... More
Great Expectations: Plans and Predictions for New Horizons Encounter with Kuiper Belt Object 2014 MU69 ('Ultima Thule')Aug 06 2018The New Horizons encounter with the cold classical Kuiper Belt object (KBO) 2014 MU69 (informally named 'Ultima Thule,' hereafter Ultima) on 1 January 2019 will be the first time a spacecraft has ever closely observed one of the free-orbiting small denizens ... More
The Transition between Nonorthogonal Polarization Modes in PSR B2016+28 at 1404 MHzJun 03 2003Polarization observations of the radio emission from PSR B2016+28 at 1404 MHz reveal properties that are consistent with two, very different, interpretations of the pulsar's viewing geometry. The pulsar's average polarization properties show a rapid change ... More
Orientation Angles of a Pulsar's Polarization VectorMar 17 2006A statistical model of the polarization of pulsar radio emission is used to derive the general statistics of a polarization vector's orientation angles. The theoretical distributions are compared with orientation angle histograms computed from single-pulse, ... More
Three-Dimensional Statistics of Radio PolarimetryJun 03 2003The measurement of radio polarization may be regarded as a three-dimensional statistical problem because the large photon densities at radio wavelengths allow the simultaneous detection of the three Stokes parameters which completely describe the radiation's ... More
Seshadri constants, Diophantine approximation, and Roth's Theorem for arbitrary varietiesJun 12 2013Apr 27 2015In this paper, we associate an invariant $\alpha_{x}(L)$ to an algebraic point $x$ on an algebraic variety $X$ with an ample line bundle $L$. The invariant $\alpha$ measures how well $x$ can be approximated by rational points on $X$, with respect to the ... More
One-Loop Single-Real-Emission Contributions to $pp\to H + X$ at Next-to-Next-to-Next-to-Leading OrderDec 04 2013Jan 31 2014I compute the contributions of the one-loop single-real-emission amplitudes, $gg\to H g$, $qg\to H q$, etc., to inclusive Higgs boson production through next-to-next-to-next-to-leading order (N^3LO) in the strong coupling $\alpha_s$. The next-to-leading ... More
The Two-Loop Infrared Structure of Amplitudes with Mixed Gauge GroupsAug 05 2013The infrared structure of (multi-loop) scattering amplitudes is determined entirely by the identities of the external particles participating in the scattering. The two-loop infrared structure of pure \qcd\ amplitudes has been known for some time. By ... More
Gluonic Three Jet Production at Next to Leading OrderSep 16 1996I report results from a next-to-leading order event generator of purely gluonic jet production. This calculation, is the first step in the construction of a full next-to-leading order calculation of three jet production at hadron colliders.
The $S^1$-Equivariant Cohomology of Spaces of Long Exact SequencesNov 14 2009Let $S$ denote the graded polynomial ring $\C[x_1,...,x_m]$. We interpret a chain complex of free $S$-modules having finite length homology modules as an $S^1$-equivariant map $\C^m\sm\{0\} \to X$, where $X$ is a moduli space of exact sequences. By computing ... More
Cops and Robbers is EXPTIME-completeSep 20 2013Dec 04 2014We investigate the computational complexity of deciding whether k cops can capture a robber on a graph G. In 1995, Goldstein and Reingold conjectured that the problem is EXPTIME-complete when both G and k are part of the input; we prove this conjecture. ... More
Next to Leading Order Three Jet Production at Hadron CollidersMay 21 1997I present results from a next-to-leading order event generator of purely gluonic jet production. This calculation is the first step in the construction of a full next-to-leading order calculation of three jet production at hadron colliders. Several jet ... More
Anomalous Condensates and the Equivalence TheoremNov 30 1993A recently published report has called into question the validity of the equivalence theorem in dynamically broken gauge theories in which the fermions making up the symmetry breaking condensate lie in an anomalous representation of the broken gauge group. ... More
One-loop Single Real Emission Contributions to Inclusive Higgs Production at NNNLOJul 25 2014Aug 11 2014I discuss the contributions of the one-loop single-real-emission amplitudes, $gg\to H g$, $qg\to H q$, etc. to inclusive Higgs boson production through next-to-next-to-next-to-leading order in the strong coupling.
Regularization Schemes and Higher Order CorrectionsFeb 25 2011Oct 03 2011I apply commonly used regularization schemes to a multi-loop calculation to examine the properties of the schemes at higher orders. I find complete consistency between the conventional dimensional regularization scheme and dimensional reduction, but I ... More
An analogue of Liouville's Theorem and an application to cubic surfacesJun 12 2013We prove a strong analogue of Liouville's Theorem in Diophantine approximation for points on arbitrary algebraic varieties. We use this theorem to prove a conjecture of the first author for cubic surfaces in $\P^3$.
Higgs Boson Production at Hadron CollidersAug 14 2002I report on a calculation of the inclusive Higgs boson production cross section at hadron colliders at next-to-next-to-leading order in QCD. The result is computed as an expansion about the threshold region. By continuing the expansion to very high order, ... More
Bounds on the length of a game of Cops and RobbersJun 26 2017Jun 19 2018In the game of Cops and Robbers, a team of cops attempts to capture a robber on a graph $G$. All players occupy vertices of $G$. The game operates in rounds; in each round the cops move to neighboring vertices, after which the robber does the same. The ... More
The Four Dimensional Helicity Scheme Beyond One LoopMay 17 2012I describe a procedure by which one can transform scattering amplitudes computed in the four dimensional helicity scheme into properly renormalized amplitudes in the 't Hooft-Veltman scheme. I describe a new renormalization program, based upon that of ... More
One-loop Integral Coefficients from Generalized UnitarityNov 30 2007May 12 2008I describe a method for determining the coefficients of scalar integrals for one-loop amplitudes in quantum field theory. The method is based upon generalized unitarity and the behavior of amplitudes when the free parameters of the cut momenta approach ... More
Subtraction Terms for Hadronic Production Processes at Next-to-Next-to-Leading OrderMar 11 2004I describe a subtraction scheme for the next-to-next-to-leading order calculation of single inclusive production at hadron colliders. Such processes include Drell-Yan, W^{+/-}, Z and Higgs Boson production. The key to such a calculation is a treatment ... More
Distinguishing Among Models of Strong W_L W_L Scattering at the LHCOct 16 1996Using a multi-channel analysis of W_L W_L scattering signals, I study the LHC's ability to distinguish among various models of strongly interacting electroweak symmetry breaking sectors.
Polarization Patterns in Pulsar Radio EmissionOct 22 2008A variety of intriguing polarization patterns are created when polarization observations of the single pulses from radio pulsars are displayed in a two-dimensional projection of the Poincare sphere. In many pulsars, the projections produce two clusters ... More
On the Excess Dispersion in the Polarization Position Angle of Pulsar Radio EmissionJan 28 2004The polarization position angles (PA) of pulsar radio emission occupy a distribution that can be much wider than what is expected from the average linear polarization and the off-pulse instrumental noise. Contrary to our limited understanding of the emission ... More
K3 surfaces, rational curves, and rational pointsSep 05 2007Jul 20 2008We prove that for any of a wide class of elliptic surfaces $X$ defined over a number field $k$, if there is an algebraic point on $X$ that lies on only finitely many rational curves, then there is an algebraic point on $X$ that lies on no rational curves. ... More
Number of binomial coefficients divided by a fixed power of a primeOct 08 2007We state a general formula for the number of binomial coefficients $n$ choose $k$ that are divided by a fixed power of a prime $p$, i.e., the number of binomial coefficients divided by $p^j$ and not divided by $p^{j+1}$.
Histogram TomographySep 27 2018In many tomographic imaging problems the data consist of integrals along lines or curves. Increasingly we encounter "rich tomography" problems where the quantity imaged is higher dimensional than a scalar per voxel, including vectors tensors and functions. ... More
The Expanded Very Large ArraySep 08 2009In almost 30 years of operation, the Very Large Array (VLA) has proved to be a remarkably flexible and productive radio telescope. However, the basic capabilities of the VLA have changed little since it was designed. A major expansion utilizing modern ... More
Polynomial Schur and Polynomial Dunford-Pettis PropertiesNov 17 1992A Banach space is {\it polynomially Schur} if sequential convergence against analytic polynomials implies norm convergence. Carne, Cole and Gamelin show that a space has this property and the Dunford-Pettis property if and only if it is Schur. Herein ... More
Far-Field Compression for Fast Kernel Summation Methods in High DimensionsSep 09 2014Feb 13 2015We consider fast kernel summations in high dimensions: given a large set of points in $d$ dimensions (with $d \gg 3$) and a pair-potential function (the {\em kernel} function), we compute a weighted sum of all pairwise kernel interactions for each point ... More
Diffeomorphism-invariant observables and their nonlocal algebraJul 28 2015Jul 15 2016Gauge-invariant observables for quantum gravity are described, with explicit constructions given primarily to leading order in Newton's constant, analogous to and extending constructions first given by Dirac in quantum electrodynamics. These can be thought ... More
Risk aware minimum principle for optimal control of stochastic differential equationsDec 21 2018We present a probabilistic formulation of risk aware optimal control problems for stochastic differential equations. Risk awareness is in our framework captured by objective functions in which the risk neutral expectation is replaced by a risk function, ... More
Bounds on the localization numberJun 13 2018Jul 09 2018We consider the localization game played on graphs, wherein a set of cops attempt to determine the exact location of an invisible robber by exploiting distance probes. The corresponding optimization parameter for a graph $G$ is called the localization ... More
Stochastic dominance-constrained Markov decision processesJun 20 2012We are interested in risk constraints for infinite horizon discrete time Markov decision processes (MDPs). Starting with average reward MDPs, we show that increasing concave stochastic dominance constraints on the empirical distribution of reward lead ... More
The proportional UAP characterizes weak Hilbert spacesDec 31 1990We prove that a Banach space has the uniform approximation property with proportional growth of the uniformity function iff it is a weak Hilbert space.
Complexity Leads to Simplicity: A Consensus Layer V Pyramidal Neuron Can Sustain Interpulse-Interval CodingSep 26 2016In terms of the long-distance communication of a single neuron, interpulse intervals (IPIs) are a possible alternative to rate and binary codes. As a proxy for IPI, the time-to-spike (TTS) for a neuron can be found in the biophysical and experimental ... More
Subspaces of $L_p$ that embed into $L_p(μ)$ with $μ$ finiteJan 17 2013Enflo and Rosenthal proved that $\ell_p(\aleph_1)$, $1 < p < 2$, does not (isomorphically) embed into $L_p(\mu)$ with $\mu$ a finite measure. We prove that if $X$ is a subspace of an $L_p$ space, $1< p < 2$, and $\ell_p(\aleph_1)$ does not embed into ... More
Cops, robbers, and burning bridgesDec 24 2018We consider a variant of Cops and Robbers wherein each edge traversed by the robber is deleted from the graph. The focus is on determining the minimum number of cops needed to capture a robber on a graph $G$, called the {\em bridge-burning cop number} ... More
Universal Non-Completely-Continuous OperatorsApr 13 1995A bounded linear operator between Banach spaces is called {\it completely continuous} if it carries weakly convergent sequences into norm convergent sequences. Isolated is a universal operator for the class of non-completely-continuous operators from ... More
Observables, gravitational dressing, and obstructions to locality and subsystemsJul 04 2016Nov 07 2016Quantum field theory - our basic framework for describing all non-gravitational physics - conflicts with general relativity: the latter precludes the standard definition of the former's essential principle of locality, in terms of commuting local observables. ... More
A Schauder basis for $L_1(0,\infty)$ consisting of non-negative functionsFeb 26 2015We construct a Schauder basis for $L_1$ consisting of non-negative functions and investigate unconditionally basic and quasibasic sequences of non-negative functions in $L_p$, $1\le p < \infty$.
Multiplication operators on L(L_p) and $\ell_p$-strictly singular operatorsAug 03 2007A classification of weakly compact multiplication operators on L(L_p), $1<p<\infty$, is given. This answers a question raised by Saksman and Tylli in 1992. The classification involves the concept of $\ell_p$-strictly singular operators, and we also investigate ... More
Game Brush NumberDec 05 2014Jan 27 2016We study a two-person game based on the well-studied brushing process on graphs. Players Min and Max alternately place brushes on the vertices of a graph. When a vertex accumulates at least as many brushes as its degree, it sends one brush to each neighbor ... More
Fabry-Perot Absorption Line Spectroscopy of the Galactic Bar. II. Stellar MetallicitiesJun 29 2009We measure the Ca II 8542 line strength in 3360 stars along three lines-of-sight in the Galactic bar: (l,b) ~ (+/-5.0,-3.5) and Baade's Window, using Fabry-Perot (FP) absorption line spectroscopy. This is the first attempt to show that reliable absorption ... More
Random constraint sampling and duality for convex optimizationOct 21 2016Nov 27 2016We are interested in solving convex optimization problems with large numbers of constraints. Randomized algorithms, such as random constraint sampling, have been very successful in giving nearly optimal solutions to such problems. In this paper, we combine ... More
Machine Learning for Drug Overdose SurveillanceOct 06 2017We describe two recently proposed machine learning approaches for discovering emerging trends in fatal accidental drug overdoses. The Gaussian Process Subset Scan enables early detection of emerging patterns in spatio-temporal data, accounting for both ... More
Stochastic Approximation for Risk-aware Markov Decision ProcessesMay 11 2018May 16 2018In this paper, we develop a stochastic approximation type algorithm to solve finite state and action, infinite-horizon, risk-aware Markov decision processes. Our algorithm is based on solving stochastic saddle-point problems for risk estimation and doing ... More
Adaptive Path Planning for Depth Constrained Bathymetric Mapping with an Autonomous Surface VesselMar 21 2016Mar 31 2016This paper describes the design, implementation and testing of a suite of algorithms to enable depth constrained autonomous bathymetric (underwater topography) mapping by an Autonomous Surface Vessel (ASV). Given a target depth and a bounding polygon, ... More
Photometric and proper motion study of neglected open cluster NGC 2215May 20 2015Optical UBVRI photometric measurements using the Faulkes Telescope North were taken in early 2011 and combined with 2MASS JHK$_s$ and WISE infrared photometry as well as UCAC4 proper motion data in order to estimate the main parameters of the galactic ... More
Observables, gravitational dressing, and obstructions to locality and subsystemsJul 04 2016Quantum field theory - our basic framework for describing all non-gravitational physics - conflicts with general relativity: the latter precludes the standard definition of the former's essential principle of locality, in terms of commuting local observables. ... More
Computing p-summing norms with few vectorsSep 22 1992It is shown that the p-summing norm of any operator with n-dimensional domain can be well-aproximated using only ``few" vectors in the definition of the p-summing norm. Except for constants independent of n and log n factors, ``few" means n if 1<p<2 and ... More
Maximum Disk Mass Models for Spiral GalaxiesSep 11 2000We present axisymmetric maximum disk mass models for a sample of 74 spiral galaxies taken from the southern sky Fabry-Perot Tully-Fisher survey (Schommer et al. 1993). The sample contains galaxies spanning a large range of morphologies and having rotation ... More
The Complete Continuity Property and Finite Dimensional DecompositionsFeb 02 1993A Banach space $\X$ has the complete continuity property (CCP) if each bounded linear operator from $L_1$ into $\X$ is completely continuous (i.e., maps weakly convergent sequences to norm convergent sequences). The main theorem shows that a Banach space ... More
Gravitational splitting at first order: Quantum information localization in gravityMay 28 2018Sep 26 2018We explore the important fundamental question of how quantum information is localized in quantum gravity, in a perturbative approach. Familiar descriptions of localization of information, such as via tensor factorization of the Hilbert space or a net ... More
Operators which factor through Banach lattices not containing c_0Feb 19 1990In this supplement to [GJ1], [GJ3], we give an intrinsic characterization of (bounded, linear) operators on Banach lattices which factor through Banach lattices not containing a copy of $c_0$ which complements the characterization of [GJ1], [GJ3] that ... More
Closed Form Analytical Model for Airflow around 2-Dimensional Composite Airfoil Via Conformal MappingDec 25 2017This paper presents a method of computing section lift characteristics for a 2-dimensional airfoil with a second 2-dimensional object at a position at or ahead of the leading edge of the airfoil. Since both objects are 2-dimensional, the analysis yields ... More
Remarks on Talagrand's deviation inequality for Rademacher functionsFeb 16 1990Recently Talagrand [T] estimated the deviation of a function on $\{0,1\}^n$ from its median in terms of the Lipschitz constant of a convex extension of $f$ to $\ell ^n_2$; namely, he proved that $$P(|f-M_f| > c) \le 4 e^{-t^2/4\sigma ^2}$$ where $\sigma$ ... More
Implications of Shock Wave Experiments with Precompressed Materials for Giant Planet InteriorsJul 31 2007This work uses density functional molecular dynamics simulations of fluid helium at high pressure to examine how shock wave experiments with precompressed samples can help characterizing the interior of giant planets. In particular, we analyze how large ... More
Random constraint sampling and duality for convex optimizationOct 21 2016We are interested in solving convex optimization problems with large numbers of constraints. Randomized algorithms, such as random constraint sampling, have been very successful in giving nearly optimal solutions to such problems. In this paper, we combine ... More
Two-Loop Virtual Corrections to Drell-Yan Production at order alpha_s alpha^3Jul 24 2011The Drell-Yan mechanism for the production of lepton pairs is one of the most basic processes for physics studies at hadron colliders. It is therefore important to have accurate theoretical predictions. In this work we compute the two-loop virtual mixed ... More
A simple reformulation of Riemann Zeta functionJan 05 2007We rewrite Riemann Zeta function as a sum over the primes. Each term of the sum is a product that depends only on the summation index (a prime) and the primes following it.
The Johnson-Lindenstrauss lemma almost characterizes Hilbert space, but not quiteJul 11 2008Let $X$ be a normed space that satisfies the Johnson-Lindenstrauss lemma (J-L lemma, in short) in the sense that for any integer $n$ and any $x_1,\ldots,x_n\in X$ there exists a linear mapping $L:X\to F$, where $F\subseteq X$ is a linear subspace of dimension ... More
Commutators on $\ell_{\infty}$Apr 20 2009Jul 26 2009The operators on $\ell_{\infty}$ which are commutators are those not of the form $\lambda I + S$ with $\lambda\neq 0$ and $S$ strictly singular.
Embedding Banach spaces into the space of bounded functions with countable supportJul 13 2018We prove that a WLD subspace of the space $\ell_\infty^c(\Gamma)$ consisting of all bounded, countably supported functions on a set $\Gamma$ embeds isomorphically into $\ell_\infty$ if and only if it does not contain isometric copies of $c_0(\omega_1)$. ... More
The Next Generation Very Large Array: A Technical OverviewJun 21 2018The next-generation Very Large Array (ngVLA) is an astronomical observatory planned to operate at centimeter wavelengths (25 to 0.26 centimeters, corresponding to a frequency range extending from 1.2 GHz to 116 GHz). The observatory will be a synthesis ... More
Spin-polarized collision of deuterium and tritium: Relativistic KinematicsFeb 26 2008Apr 17 2008We investigate the relativistic kinematics of the spin-polarized collision of deuterium incident on tritium, producing ${}^4$He and a neutron. Within the context of special relativity, we apply the conservation of four momentum and the conservation of ... More
The Geology of Pluto and Charon Through the Eyes of New HorizonsApr 19 2016NASA's New Horizons spacecraft has revealed the complex geology of Pluto and Charon. Pluto's encounter hemisphere shows ongoing surface geological activity centered on a vast basin containing a thick layer of volatile ices that appears to be involved ... More
Convection in a volatile nitrogen-ice-rich layer drives Pluto's geological vigorMar 13 2019The vast, deep, volatile-ice-filled basin informally named Sputnik Planum is central to Pluto's geological activity[1,2]. Composed of molecular nitrogen, methane, and carbon monoxide ices[3], but dominated by N2-ice, this ice layer is organized into cells ... More
Unscented External Force and Torque Estimation for QuadrotorsMar 09 2016Aug 02 2016In this paper, we describe an algorithm, based on the well-known Unscented Quaternion Estimator, to estimate external forces and torques acting on a quadrotor. This formulation uses a non-linear model for the quadrotor dynamics, naturally incorporates ... More
Bias correction in daily maximum and minimum temperature measurements through Gaussian process modelingMay 25 2018May 29 2018The Global Historical Climatology Network-Daily database contains, among other variables, daily maximum and minimum temperatures from weather stations around the globe. It is long known that climatological summary statistics based on daily temperature ... More
Learn Fast, Forget Slow: Safe Predictive Learning Control for Systems with Unknown and Changing Dynamics Performing Repetitive TasksOct 15 2018Apr 09 2019We present a control method for improved repetitive path following for a ground vehicle that is geared towards long-term operation where the operating conditions can change over time and are initially unknown. We use weighted Bayesian Linear Regression ... More
Theory of Radio Frequency Spectroscopy of Polarized Fermi GasesMar 17 2009We present two exact results for singular features in the radio frequency intensity $I(\omega)$ for ultracold Fermi gases. First, in the absence of final state interactions, $I(\omega)$ has a universal high frequency tail $ C\omega^{-3/2}$ for \emph{all} ... More
$W^+Z$ and $W^+γ^*$ Backgrounds to Strong $W^+W^+$ Scattering at the LHCDec 12 1994Because of inevitable blind spots at high rapidity and low transverse momentum, the process $\overline qq \rightarrow l^+ l^- \ l^{+} \nu$ provides a surprisingly large background to the $W^+W^+ \rightarrow l^+ \nu \ l^+ \nu$ signal associated with strong ... More
Tradeoff between Efficiency and Melting for a High-Performance Electromagnetic Rail GunOct 16 2008Aug 11 2010We estimate the temperature distribution in the rails of an electromagnetic rail gun (EMG) due to the confinement of the current in a narrow surface layer resulting from the skin effect. In order to obtain analytic results, we assume a simple geometry ... More
An efficient Matched Filtering Algorithm for the Detection of Continuous Gravitational Wave SignalsDec 08 1999We describe an efficient method of matched filtering over long (greater than 1 day) time baselines starting from Fourier transforms of short durations (roughly 30 minutes) of the data stream. This method plays a crucial role in the search algorithm developed ... More
Fabry-Perot Absorption-Line Spectroscopy of NGC 7079Sep 17 1999We report on absorption-line Fabry-Perot spectroscopy of the SB0 galaxy NGC 7079. Our data allow us to determine velocity and dispersion maps, which compare well with the results of slit observations. Our goals are to obtain a bar pattern speed and to ... More
Neural computation from first principles: Using the maximum entropy method to obtain an optimal bits-per-joule neuronJun 06 2016Dec 19 2017Optimization results are one method for understanding neural computation from Nature's perspective and for defining the physical limits on neuron-like engineering. Earlier work looks at individual properties or performance criteria and occasionally a ... More
Reconstruction of spatially inhomogeneous dielectric tensors via optical tomographyJun 11 2004Jun 29 2004A method to reconstruct weakly anisotropic inhomogeneous dielectric tensors inside a transparent medium is proposed. The mathematical theory of Integral Geometry is cast into a workable framework which allows the full determination of dielectric tensor ... More
Index-Based Policy for Risk-Averse Multi-Armed BanditSep 14 2018The multi-armed bandit (MAB) is a classical online optimization model for the trade-off between exploration and exploitation. The traditional MAB is concerned with finding the arm that minimizes the mean cost. However, minimizing the mean does not take ... More
Commutators on $L_p$, $1\le p<\infty$Feb 01 2011The operators on $\LP=L_p[0,1]$, $1\leq p<\infty$, which are not commutators are those of the form $\lambda I + S$ where $\lambda\neq 0$ and $S$ belongs to the largest ideal in $\opLP$. The proof involves new structural results for operators on $\LP$ ... More
Angular distribution of thick-target bremsstrahlung produced by electrons with initial energies ranging from 10 to 20-keV incident on AgFeb 20 2013Experimental results are presented comparing the intensity of the bremsstrahlung produced by electrons with initial energies ranging from 10 to 20-keV incident on a thick Ag target, measured at forward angles in the range 0 degrees to 55 degrees. When ... More
Higgs boson production in bottom quark fusion at next-to-next-to-leading orderApr 03 2003Jul 02 2003The total cross section for Higgs production in bottom-quark annihilation is evaluated at next-to-next-to-leading order (NNLO) in QCD. This is the first time that all terms at order alpha_s^2 are taken into account. We find a greatly reduced scale dependence ... More
Next-to-Next-to-Leading Order Higgs Production at Hadron CollidersJan 22 2002May 09 2002The Higgs boson production cross section at pp and p\bar{p} colliders is calculated in QCD at next-to-next-to-leading order (NNLO). We find that the perturbative expansion of the production cross section is well behaved and that scale dependence is reduced ... More
Production of a pseudo-scalar Higgs boson at hadron colliders at next-to-next-to leading orderAug 12 2002Oct 22 2002The production cross section for pseudo-scalar Higgs bosons at hadron colliders is computed at next-to-next-to-leading order (NNLO) in QCD. The pseudo-scalar Higgs is assumed to couple only to top quarks. The NNLO effects are evaluated using an effective ... More