Results for "Donald V. Reames"

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The "FIP Effect" and the Origins of Solar Energetic Particles and of the Solar WindJan 17 2018We find that the element abundances in solar energetic particles (SEPs) and in the slow solar wind (SSW), relative to those in the photosphere, show different patterns as a function of the first ionization potential (FIP) of the elements. Generally, the ... More
Hydrogen and the Abundances of Elements in Impulsive Solar Energetic-Particle EventsJan 14 2019Hydrogen has been almost completely ignored in studies of the abundance patterns of the chemical elements in solar energetic particles (SEPs). We seek to find impulsive events where H fits these abundance patterns and document the events that do not, ... More
Hydrogen and the Abundances of Elements in Gradual Solar Energetic-Particle EventsFeb 08 2019Despite its dominance, hydrogen has been largely ignored in studies of the abundance patterns of the chemical elements in gradual solar energetic-particle (SEP) events; those neglected abundances show a surprising new pattern of behavior. Abundance enhancements ... More
Element Abundances and Source Plasma Temperatures of Solar Energetic ParticlesNov 30 2016Dec 05 2016Thirty years ago Breneman and Stone observed that the enhancement or suppression of element abundances in large solar energetic-particle (SEP) events varies as a power of the mass-to-charge ratio, A/Q, of the elements. Since Q during acceleration or transport ... More
The Streaming Limit of Solar Energetic-Particle IntensitiesDec 06 2014As solar energetic particles (SEPs) stream outward along the interplanetary magnetic field after acceleration by shock waves near the Sun, their intensities are limited by scattering against self-generated Alfv\'en waves, trapping the particles near their ... More
Temperature of the Source Plasma for Impulsive Solar Energetic ParticlesMay 11 2015The steep power-law dependence of element abundance enhancements on the mass-to-charge ratios [A/Q] of the ions in impulsive solar energetic-particle (SEP) events causes these enhancements to reflect the temperature-dependent pattern of Q of the ions ... More
Element Abundances in Solar Energetic Particles and the Solar CoronaJun 10 2013This is a study of abundances of the elements He, C, N, O, Ne, Mg, Si, S, Ar, Ca, and Fe in solar energetic particles (SEPs) in the 2 - 15 MeV amu-1 region measured on the Wind spacecraft during 54 large SEP events occurring between November 1994 and ... More
The Origin of Element Abundance Variations in Solar Energetic ParticlesMar 20 2016Jul 21 2016Abundance enhancements, during acceleration and transport in both gradual and impulsive solar energetic particle (SEP) events, vary approximately as power laws in the mass-to-charge ratio [A/Q] of the ions. Since the Q-values depend upon the electron ... More
Element Abundances and Source Plasma Temperatures of Solar Energetic ParticlesNov 30 2016Thirty years ago Breneman and Stone observed that the enhancement or suppression of element abundances in large solar energetic-particle (SEP) events varies as a power of the mass-to-charge ratio, A/Q, of the elements. Since Q during acceleration or transport ... More
Element abundances in solar energetic particles: two physical processes, two abundance patternsJan 03 2015Abundances of elements comprising solar energetic particles (SEPs) come with two very different patterns. Historically called "impulsive" and "gradual" events, they have been studied for 40 years, 20 years by the Wind spacecraft. Gradual SEP events measure ... More
Variations in Abundance Enhancements in Impulsive Solar Energetic-Particle Events and Related CMEs and FlaresJul 29 2014We study event-to-event variations in the abundance enhancements of the elements He through Pb for Fe-rich impulsive solar energetic-particle (SEP) events, and their relationship with properties of associated coronal mass ejections (CMEs) and solar flares. ... More
Abundance Enhancements in Impulsive Solar Energetic-Particle Events with Associated Coronal Mass EjectionsApr 12 2014We study the abundances of the elements He through Pb in Fe-rich impulsive solar energetic-particle (SEP) events with measurable abundances of ions with atomic number Z>2 observed on the Wind spacecraft, and their relationship with coronal mass ejections ... More
Coronal Sources of Impulsive Fe-Rich Solar Energetic Particle EventsSep 30 2015We review recent work on 111 Fe-rich impulsive solar energetic ($\sim$ 3 MeV/nuc) particle (SEP) events observed from 1994 to 2013. Strong elemental abundance enhancements scale with A/Q, the ion mass-to-charge ratio, as (A/Q)$^{\alpha}$, where 2 $< \alpha ... More
The Design Of Fiber Optic Sensors For Measuring Hydrodynamic ParametersMar 31 2002We present an approximate analytic model that has been developed for examining hydrodynamic flow near the surface of a fiber optic sensor. An analysis of the conservation of momentum, the continuity equation and the Navier-Stokes equation for compressible ... More
RXTE All-Sky Monitor Localization of SGR 1627-41Mar 10 1999May 12 1999The fourth unambiguously identified Soft Gamma Repeater (SGR), SGR1627-41, was discovered with the BATSE instrument on 1998 June 15 (Kouveliotou et al. 1998). Interplanetary Network (IPN) measurements and BATSE data constrained the location of this new ... More
Neutral interstellar helium parameters based on Ulysses/GAS and IBEX-Lo observations: what are the reasons for the differences?Mar 12 2014May 19 2014Recent analysis of the interstellar helium fluxes measured in 2009-2010 at Earth orbit by the Interstellar Boundary Explorer (IBEX) has suggested that the interstellar velocity (both direction and magnitude) is inconsistent with that derived previously ... More
The Redshift of a Lensing Galaxy in PMN J0134-0931Jul 15 2002The Sloan Digital Sky Survey (SDSS) automatically targeted as a quasar candidate the recently discovered, gravitationally lensed, extremely reddened z=2.2 quasar PMN J0134-0931. The SDSS spectrum exhibits Ca II absorption at z=0.76451, which we identify ... More
Detiding DART buoy data for real-time extraction of source coefficients for operational tsunami forecastingMar 03 2014U.S. Tsunami Warning Centers use real-time bottom pressure (BP) data transmitted from a network of buoys deployed in the Pacific and Atlantic Oceans to tune source coefficients of tsunami forecast models. For accurate coefficients and therefore forecasts, ... More
Dwyer-Kan Homotopy Theory of Algebras over Operadic CollectionsAug 05 2016Over suitable monoidal model categories, we construct a Dwyer-Kan model category structure on the category of algebras over an augmented operadic collection. As examples we obtain Dwyer-Kan model category structure on the categories of enriched wheeled ... More
A remark on the genus of the infinite quaternionic projective spaceJun 23 2001Jul 01 2001It is shown that only countably many spaces in the genus of $\hpinfty$, the infinite quaternionic projective space, can admit essential maps from $\cpinfty$, the infinite complex projective space. Examples of countably many homotopically distinct spaces ... More
Cohomology of truncated polynomial lambda-ringsJan 28 2005The lambda-ring cohomology in dimensions 0 and 1 of certain truncated polynomial filtered lambda-rings are computed. The dimension 1 case is related to deformations of lambda-rings.
Photospheric Emission from Collapsar Jets in 3D Relativistic HydrodynamicsNov 11 2015Nov 27 2015We explore the photospheric emission from a relativistic jet breaking out from a massive stellar envelope based on relativistic hydrodynamical simulations and post-process radiation transfer calculations in three dimensions. To investigate the impact ... More
Exponential equilibration by slow cooling in the planar random-anisotropy magnet: experiments and simulationsJul 22 2008Neutron measurements of the equilibration of the staggered magnetization in DyAs(0.35)V(0.65)O4 are compared with Monte Carlo simulations of spin dynamics in a planar random-anisotropy magnet. The simulation results are in agreement with striking observed ... More
Hom-power associative algebrasJul 23 2010A generalization of power associative algebra, called Hom-power associative algebra, is studied. The main result says that a multiplicative Hom-algebra is Hom-power associative if and only if it satisfies two identities of degrees three and four. It generalizes ... More
The Hom-Yang-Baxter equation and Hom-Lie algebrasMay 12 2009Feb 17 2011Motivated by recent work on Hom-Lie algebras, a twisted version of the Yang-Baxter equation, called the Hom-Yang-Baxter equation (HYBE), was introduced by the author in an earlier paper. In this paper, several more classes of solutions of the HYBE are ... More
Hom-bialgebras and comodule Hom-algebrasOct 27 2008Mar 15 2010We study Hom-bialgebras and objects admitting coactions by Hom-bialgebras. In particular, we construct a Hom-bialgebra M representing the functor of 2x2-matrices on Hom-associative algebras. Then we construct a Hom-algebra analogue of the affine plane ... More
Cohomology and deformation of module-algebrasJul 12 2006An algebraic deformation theory of module-algebras over a bialgebra is constructed. The cases of module-coalgebras, comodule-algebras, and comodule-coalgebras are also considered.
Learning compact q-space representations for multi-shell diffusion-weighted MRIJun 17 2018Oct 08 2018Diffusion-weighted MRI measures the direction and scale of the local diffusion process in every voxel through its spectrum in q-space, typically acquired in one or more shells. Recent developments in microstructure imaging and multi-tissue decomposition ... More
Stellar Iron Abundances at the Galactic CenterFeb 02 2000We present measurements of [Fe/H] for six M supergiant stars and three giant stars within 0.5 pc of the Galactic Center (GC) and one M supergiant star within 30 pc of the GC. The results are based on high-resolution (lambda / Delta lambda =40,000) K-band ... More
Upscaled Lattice Boltzmann Method for Simulations of Flows in Heterogeneous Porous MediaDec 01 2013A upscaled lattice Boltzmann method (LBM) for flow simulations in heterogeneous porous media, at both pore and Darcy scales, is proposed in this paper. In the micro-scale simulations, we model flows using LBM with the modified Guo et al. algorithm where ... More
On reconciling quantum mechanics and local realismSep 04 2013A necessary and natural change in our application of quantum mechanics to separated systems is shown to reconcile quantum mechanics and local realism. An analysis of separation and localization justifies the proposed change in application of quantum mechanics. ... More
Right Bousfield Localization and Operadic AlgebrasDec 23 2015It is well known that under some general conditions right Bousfield localization exists. We provide general conditions under which right Bousfield localization yields a monoidal model category. Then we address the questions of when this monoidal model ... More
For objective causal inference, design trumps analysisNov 11 2008For obtaining causal inferences that are objective, and therefore have the best chance of revealing scientific truths, carefully designed and executed randomized experiments are generally considered to be the gold standard. Observational studies, in contrast, ... More
A classification of nullity classes in the derived category of a ringOct 29 2016For a commutative Noetherian ring $R$ with finite Krull dimension, we study the nullity classes in $D^c_{fg}(R)$, the full triangulated subcategory $D^c_{fg}(R)$ of the derived category $D(R)$ consisting of objects which can be represented by cofibrant ... More
A classification of nullity classes in abelian categoriesOct 29 2016Nov 22 2016We give a classification of nullity classes (or torsion classes) in an abelian category by forming a spectrum of equivalence classes of premonoform objects. This is parallel to Kanda's classification of Serre subcategories.
Enumerating lattices of subsetsNov 26 2013Dec 10 2013Given k sets such that no one is contained in another, there is an associated lattice on the power set P([k]) corresponding to inclusion relations among unions of the sets. Two lattices on P([k]) are equivalent if there is a permutation of [k] under which ... More
For which p-adic integers x can Sum_k binomial(x,k)^(-1) be defined?Aug 01 2012Let f(n)= Sum binomial(n,k)^(-1). First, we show that f:N to Q_p is nowhere continuous in the p-adic topology. If x is a p-adic integer, we say that f(x) is p-definable if lim f(x_j) exists in Q_p, where x_j denotes the jth partial sum for x. We prove ... More
Some new nonimmersion results for real projective spacesJan 28 2011We use the spectrum tmf to obtain new nonimmersion results for many real projective spaces RP^n for n as small as 113. The only new ingredient is some new calculations of tmf-cohomology groups. We present an expanded table of nonimmersion results. Our ... More
Diagnosing the Prominence-Cavity ConnectionApr 29 2013Prominences and cavities are ubiquitously observed together, but the physical link between these disparate structures has not been established. We address this issue by using dynamic emission in the extreme ultraviolet (EUV) to probe the connections of ... More
Minimizing Squared Perpendicular ErrorsDec 02 2005The best fit line from minimizing the sum of the squared perpendicular error is given.
Throughput Analysis of Proportional Fair Scheduling For Sparse and Ultra-Dense Interference-Limited OFDMA/LTE NetworksOct 22 2015Jan 27 2016Various system tasks like interference coordination, handover decisions, admission control etc. in current cellular networks require precise mid-term (spanning over a few seconds) performance models. Due to channel-dependent scheduling at the base station, ... More
The Role of Dust in GRB AfterglowsJul 28 2001We show that the clumpy structure of star-forming regions can naturally explain the fact that 50-70% of GRB afterglows are optical``dark.'' We also show that dust echos from the GRB and its afterglow, produced by the clumpy structure of the star-forming ... More
Squark Mass Determination at the Next Generation of Linear $e^+e^-$ CollidersOct 04 1993Current mass limits allow the possibility that squarks may be produced in large numbers at the next generation of linear $e^+e^-$ colliders. In this paper we investigate the prospects for precision studies of squark masses at such colliders. We assume ... More
Large deviations for the Fleming-Viot process with neutral mutation and selectionSep 17 1998Large deviation principles are established for the Fleming-Viot processes with neutral mutation and selection, and the corresponding equilibrium measures as the sampling rate goes to 0. All results are first proved for the finite allele model, and then ... More
A mini-max problem for self-adjoint Toeplitz matricesSep 14 2010Jan 18 2011We study a minimum problem and associated maximum problem for finite, complex, self-adjoint Toeplitz matrices. If $A$ is such a matrix, of size $(N+1)$-by-$(N+1)$, we identify $A$ with the operator it represents on $P_N$, the space of complex polynomials ... More
The topological complexity of the Klein bottle equals 5Dec 08 2016We use obstruction theory to prove that the topological complexity of the Klein bottle equals 5, a new result.
The Formation of a Cavity in a 3D Flux RopeNov 11 2013There are currently no three dimensional numerical models which describe the magnetic and energetic formation of prominences self-consistently. Consequently, there has not been significant progress made in understanding the connection between the dense ... More
Chief factors covered by projectors of soluble Leibniz algebrasOct 10 2011Let F be a saturated formation of soluble Leibniz algebras. Let K be an F-projector and A/B a chief factor of the soluble Leibniz algebra L. It is well-known that if A/B is F-central, then K covers A/B. I prove the converse: if K covers A/B, then A/B ... More
On $\mathfrak F$-hypercentral modules and character clustersAug 03 2016Let $\mathfrak F$ be a saturated formation of soluble Lie algebras over a field $F$ of characteristic $p > 0$ and let ${\mathbb F}_p$ denote the field of $p$ elements. Let $(L,[p])$ be a restricted Lie algebra over $F$ with $z^{$\scriptstyle [p]$}=0$ ... More
On (n+2)-dimensional n-Lie algebrasApr 15 2007I show that an (n+2)-dimensional n-Lie algebra over an algebraically closed field must have a subalgeba of codimension 1.
Character clusters for Lie algebra modules over a field of non-zero characteristicJan 20 2013For a Lie algebra L over an algebraically closed field of non-zero characteristic, every finite-dimensional L-module can be decomposed into a direct sum of submodules such that all composition factors of a summand have the same character. Using the concept ... More
Generalized Fréchet Bounds for Cell Entries in Multidimensional Contingency TablesAug 09 2017Nov 20 2017We consider the lattice, $\mathcal{L}$, of all subsets of a multidimensional contingency table and establish the properties of monotonicity and supermodularity for the marginalization function, $n(\cdot)$, on $\mathcal{L}$. We derive from the supermodularity ... More
Percolation in an ultrametric spaceJun 23 2010May 23 2012We study percolation on the hierarchical lattice of order $N$ where the probability of connection between two points separated by distance $k$ is of the form $c_k/N^{k(1+\delta)},\; \delta >-1$. Since the distance is an ultrametric, there are significant ... More
Theory and practiceNov 01 1991The author argues to Silicon Valley that the most important and powerful part of computer science is work that is simultaneously theoretical and practical. He particularly considers the intersection of the theory of algorithms and practical software development. ... More
A note on digitized anglesApr 01 1990We study the configurations of pixels that occur when two digitized straight lines meet each other.
When Acting as a Reproductive Barrier Leading to Sympatric Speciation, Hybrid Sterility Can Only be PrimaryFeb 06 2018Parental gametes unite to form a zygote that develops into an adult with gonads that, in turn, produce gametes. Interruption of this germinal cycle by prezygotic or postzygotic reproductive barriers can result in two independent cycles, each with the ... More
Robust Low-rank Tensor Recovery: Models and AlgorithmsNov 24 2013Robust tensor recovery plays an instrumental role in robustifying tensor decompositions for multilinear data analysis against outliers, gross corruptions and missing values and has a diverse array of applications. In this paper, we study the problem of ... More
p-adic Stirling numbers of the second kindJul 29 2013Let S(n,k) denote the Stirling numbers of the second kind. We prove that the p-adic limit of S(p^e a + c, p^e b + d) as e goes to infinity exists for all integers a, b, c, and d. We call the limiting p-adic integer S(p^\infty a + c, p^\infty b + d). When ... More
Topological complexity (within 1) of the space of isometry classes of planar n-gons for sufficiently large nAug 30 2016Sep 07 2016Hausmann and Rodriguez classified spaces of isometry classes of planar n-gons according to their genetic code, which is a collection of sets (called genes) containing n. Omitting the n yields what we call gees. We prove that, for a set of gees with largest ... More
v1-Periodic 2-exponents of SU(2^e) and SU(2^e + 1)Sep 22 2011We determine precisely the largest v1-periodic homotopy groups of SU(2^e) and SU(2^e + 1). This gives new results about the largest actual homotopy groups of these spaces. Our proof relies on results about 2-divisibility of restricted sums of binomial ... More
Divisibility by 2 and 3 of certain Stirling numbersJul 16 2008The numbers e_p(k,n) defined as min(nu_p(S(k,j)j!): j >= n) appear frequently in algebraic topology. Here S(k,j) is the Stirling number of the second kind, and nu_p(-) the exponent of p. The author and Sun proved that if L is sufficiently large, then ... More
From Representation Theory to Homotopy GroupsDec 09 1998Bousfield recently gave a formula for the odd-primary v1-periodic homotopy groups of a finite H-space in terms of its K-theory and Adams operations. We apply Bousfield's theorem to give explicit determinations of the v1-periodic homotopy groups of (E8,5) ... More
Duality and Central Charges in Supersymmetric Quantum MechanicsNov 11 2003We identify a class of point-particle models that exhibit a target-space duality. This duality arises from a construction based on supersymmetric quantum mechanics with a non-vanishing central charge. Motivated by analogies to string theory, we are led ... More
Binomial coefficients involving infinite powers of primesJan 26 2013If p is a prime and n a positive integer, let v(n) denote the exponent of p in n, and u(n)=n/p^{v(n)} the unit part of n. If k is a positive integer not divisible by p, we show that the p-adic limit of (-1)^{pke} u((kp^e)!) as e goes to infinity is a ... More
Statistical Implications of the Revenue Transfer Methodology in the Affordable Care ActMar 03 2017Jun 07 2018The Affordable Care Act (ACA) includes a permanent revenue transfer methodology which provides financial incentives to health insurance plans that have higher than average actuarial risk. In this paper, we derive some statistical implications of the revenue ... More
Maximizing a combinatorial expression arising from crowd estimationOct 29 2009We determine, within 1, the value of N for which sum (s1 choose i)(s2 choose N)(s1 choose N-i)(N choose i) achieves its maximum value. Here s1 and s2 are fixed integers. This problem arises in studying the most likely value for the size of the union of ... More
Strong containment of saturated formations of soluble Lie algebrasAug 08 2012Dec 03 2012It is shown that, if H,K are saturated formations of soluble Lie algebras over a field of non-zero characteristic and H strongly contains K non-trivially, then H coincides with the formation generated by the L/N(L) for L in H, and that H is not locally ... More
Engel subalgebras of n-Lie algebrasOct 10 2006Engel subalgebras of finite-dimensional n-Lie algebras are shown to have similar properties to those of Lie algebras. Using these, it is shown that an n-Lie algebra, all of whose maximal subalgebras are ideals, is nilpotent. A primitive 2-soluble n-Lie ... More
Distance Correlation: A New Tool for Detecting Association and Measuring Correlation Between Data SetsAug 14 2017The difficulties of detecting association, measuring correlation, and establishing cause and effect have fascinated mankind since time immemorial. Democritus, the Greek philosopher, underscored well the importance and the difficulty of proving causality ... More
Integral Transform Methods in Goodness-of-Fit Testing, I: The Gamma DistributionsOct 16 2018We apply the method of Hankel transforms to develop goodness-of-fit tests for gamma distributions with given shape parameter and unknown rate parameter, thereby extending results of Baringhaus and Taherizadeh (2010) on the exponential distributions. We ... More
Causal Inference Through Potential Outcomes and Principal Stratification: Application to Studies with "Censoring" Due to DeathDec 27 2006Causal inference is best understood using potential outcomes. This use is particularly important in more complex settings, that is, observational studies or randomized experiments with complications such as noncompliance. The topic of this lecture, the ... More
Does horizon entropy satisfy a Quantum Null Energy Conjecture?Jun 15 2016Nov 03 2016A modern version of the idea that the area of event horizons gives $4G$ times an entropy is the Hubeny-Rangamani Causal Holographic Information (CHI) proposal for holographic field theories. Given a region $R$ of a holographic QFTs, CHI computes $A/4G$ ... More
Flowing Funnels: Heat sources for field theories and the AdS_3 dual of CFT_2 Hawking radiationFeb 23 2012We construct the general 2+1 dimensional asymptotically AdS_3 solution dual to a stationary 1+1 CFT state on a black hole background. These states involve heat transport by the CFT between the 1+1 black hole and infinity (or between two 1+1 black holes), ... More
Multiple Point Criticality, Nonlocality, and Finetuning in fundamental physics: predictions for Gauge Coupling Constants gives $α^{-1}=136._8\pm 9Jul 16 1996The Multiple Point Criticality Principle (MPCP) states that action parameters - in for example a field theory - take on values corresponding to the junction of a maximum number of phases in the phase diagram of a system that undergoes phase transitions. ... More
Right Bousfield Localization and Eilenberg-Moore CategoriesSep 12 2016We compare several recent approaches to studying right Bousfield localization and algebras over monads. We prove these approaches are equivalent, and we apply this equivalence to obtain several new results regarding right Bousfield localizations (some ... More
Topological complexity of some planar polygon spacesApr 03 2015Jul 06 2015Using known results about their mod-2 cohomology ring, we prove that the topological complexity of the space of isometry classes of n-gons in the plane with one side of length r and all others of length 1 equals either 2n-5 or 2n-6, provided that n-r ... More
2-adic Stirling functions and their zerosFeb 03 2014Let $P_n(x)=\frac1{n!}\sum\binom n{2i+1}(2i+1)^x$. This extends to a continuous function on the 2-adic integers, the $n$th 2-adic partial Stirling function. We show that $(-1)^{n+1}P_n$ is the only 2-adically continuous approximation to $S(x,n)$, the ... More
Some new immersion results for complex projective spaceFeb 21 2006We prove the following two new optimal immersion results for complex projective space. First, if n equiv 3 mod 8 but n not equiv 3 mod 64, and alpha(n)=7, then CP^n can be immersed in R^{4n-14}. Second, if n is even and alpha(n)=3, then CP^n can be immersed ... More
Real projective space as a space of planar polygonsJan 12 2015Jan 16 2015We prove that real projective space RP^{n-3} is homeomorphic to the space of all isometry classes of n-gons in the plane with one side of length n-2 and all other sides of length 1. This makes the topological complexity of real projective space more relevant ... More
For which 2-adic integers $x$ can $\sum_k \binom xk^{-1}$ be defined?Jan 11 2013Let $f(n)=\sum_k \binom nk^{-1}$. In a previous paper, we defined for a p-adic integer x that f(x) is p-definable if lim $f(x_j)$ exists in $Q_p$, where $x_j$ denotes the mod $p^j$ reduction of $x$. We proved that if p is odd, then -1 is the only element ... More
Multilevel mutation-selection systems and set-valued dualsJul 10 2015Oct 06 2015A class of measure-valued processes which model multilevel populations undergoing mutation, selection, genetic drift and spatial migration is considered. We investigate the qualitative behaviour of models with multilevel selection and the interaction ... More
Lie algebra F-normalisers are intravariantDec 20 2007Let F be a saturated formation of soluble Lie algebras and let U be an F-normaliser of the soluble Lie algebra L. Then U is intravariant in L.
Minimizing Squared Vertical and Squared Horizontal ErrorsDec 02 2005The slope of the best fit line from minimizing the sum of both the squared vertical errors and the squared horizontal errors is shown to be the root of a fourth degree polynomial.
Extrasolar Planet Transits Observed at Kitt Peak National ObservatoryFeb 13 2012We obtained J-, H- and JH-band photometry of known extrasolar planet transiting systems at the 2.1-m Kitt Peak National Observatory Telescope using the FLAMINGOS infrared camera between October 2008 and October 2011. From the derived lightcurves we have ... More
Evolution of Star-forming Galaxies from z = 0.7 to 1.2 with eBOSS Emission-line GalaxiesOct 12 2018Feb 06 2019We study the evolution of star-forming galaxies with $10^{10} M_\odot<M_*<10^{11.6} M_\odot$ over the redshift range of 0.7<z<1.2 using the emission line galaxies (ELGs) in the extended Baryon Oscillation Spectroscopic Survey (eBOSS). By applying the ... More
Magellan LDSS3 emission confirmation of galaxies hosting metal-rich Lyman-alpha absorption systemsJul 29 2015Mar 01 2016Using the Low Dispersion Survey Spectrograph 3 at the Magellan II Clay Telescope, we target {candidate absorption host galaxies} detected in deep optical imaging {(reaching limiting apparent magnitudes of 23.0-26.5 in $g, r, i,$ and $z$ filters) in the ... More
A Monte Carlo Approach to Evolution of the Far-Infrared Luminosity Function with BLASTOct 06 2010Jul 27 2011We constrain the evolution of the rest-frame far-infrared (FIR) luminosity function out to high redshift, by combining several pieces of complementary information provided by the deep Balloon-borne Large-Aperture Submillimeter Telescope surveys at 250, ... More
Particle spectra and efficiency in nonlinear relativistic shock acceleration: survey of scattering modelsDec 09 2015We include a general form for the scattering mean free path in a nonlinear Monte Carlo model of relativistic shock formation and Fermi acceleration. Particle-in-cell (PIC) simulations, as well as analytic work, suggest that relativistic shocks tend to ... More
Monte Carlo Simulations of Nonlinear Particle Acceleration in Parallel Trans-relativistic ShocksAug 23 2013We present results from a Monte Carlo simulation of a parallel collisionless shock undergoing particle acceleration. Our simulation, which contains parameterized scattering and a particular thermal leakage injection model, calculates the feedback between ... More
Multiscale Sub-grid Correction Method for Time-Harmonic High-Frequency Elastodynamics with Wavenumber Explicit BoundsAug 15 2016The simulation of the elastodynamics equations at high-frequency suffers from the well known pollution effect. The results of this work are two-fold. We present a Petrov--Galerkin multiscale sub-grid correction method that remains pollution free in natural ... More
The 1-line of the K-theory Bousfield-Kan spectral sequence for Spin(2n+1)Sep 21 1999For X a simply-connected finite H-space, there is a Bousfield-Kan spectral sequence which converges to the homotopy of its K-completion. When X=Spin(2n+1), we expect that these homotopy groups equal the v1-periodic homotopy groups in dimension greater ... More
Non-differentiable Skew Convolution Semigroups and Related Ornstein-Uhlenbeck ProcessesJun 24 2006It is proved that a general non-differentiable skew convolution semigroup associated with a strongly continuous semigroup of linear operators on a real separable Hilbert space can be extended to a differentiable one on the entrance space of the linear ... More
Upscaling Singular Sources in Weighted Sobolev Spaces by Sub-Grid CorrectionsFeb 06 2018In this paper, we develop a numerical multiscale method to solve elliptic boundary value problems with heterogeneous diffusion coefficients and with singular source terms. When the diffusion coefficient is heterogeneous, this adds to the computational ... More
Construction of Immigration Superprocesses with Dependent Spatial Motion from One-Dimensional ExcursionsJun 24 2006A superprocess with dependent spatial motion and interactive immigration is constructed as the pathwise unique solution of a stochastic integral equation carried by a stochastic flow and driven by Poisson processes of one-dimensional excursions.
Invasion by rare mutants in a spatial two-type Fisher-Wright system with selectionApr 01 2011We consider a meanfield system of interacting Fisher-Wright diffusions with selection and rare mutation on the geographic space $\{1,2,...,N\}$. The type 1 has fitness 0, type 2 has fitness 1 and (rare) mutation occurs from type 1 to 2 at rate $m...N^{-1}$, ... More
Beyond first-order asymptotics for Cox regressionApr 13 2015To go beyond standard first-order asymptotics for Cox regression, we develop parametric bootstrap and second-order methods. In general, computation of $P$-values beyond first order requires more model specification than is required for the likelihood ... More
Nonimmersions of RP^n implied by tmf, revisitedApr 05 2007In a 2002 paper, the authors and Bruner used the new spectrum tmf to obtain some new nonimmersions of real projective spaces. In this note, we complete/correct two oversights in that paper. The first is to note that in that paper a general nonimmersion ... More
The spectrum of the averaging operator on a network (metric graph)Sep 26 2005A network is a countable, connected graph X viewed as a one-complex, where each edge [x,y]=[y,x] (x,y in X^0, the vertex set) is a copy of the unit interval within the graph's one-skeleton X^1 and is assigned a positive conductance c(xy). A reference ... More
Comments on the Neyman-Fisher Controversy and Its ConsequencesSep 09 2014The Neyman-Fisher controversy considered here originated with the 1935 presentation of Jerzy Neyman's Statistical Problems in Agricultural Experimentation to the Royal Statistical Society. Neyman asserted that the standard ANOVA F-test for randomized ... More
Assessing the Potential Impact of a Nationwide Class-Based Affirmative Action SystemSep 11 2015We examine the possible consequences of a change in law school admissions in the United States from an affirmative action system based on race to one based on socioeconomic class. Using data from the 1991-1996 Law School Admission Council Bar Passage ... More