Results for "Gary R. Goldstein"

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Nucleon Tensor Charge from Exclusive $π^o$ ElectroproductionMay 23 2008Feb 02 2009Exclusive $\pi^o$ electroproduction from nucleons is suggested for extracting the tensor charge and other quantities related to transversity from experimental data. This process isolates C-parity odd and chiral odd combinations of t-channel exchange quantum ... More
Chiral-Odd Generalized Parton Distributions from Exclusive pi^o ElectroproductionJul 12 2008Exclusive $\pi^o$ electroproduction is suggested for extracting both the tensor charge and the transverse anomalous magnetic moment from experimental data. A connection between partonic degrees of freedom, given in terms of Generalized Parton Distributions, ... More
Transversity via Exclusive pi0 ElectroproductionOct 12 2008Oct 20 2008Exclusive pi0 electroproduction from nucleons can be related to transversity, the tensor charge, and other quantities related to transversity. This process isolates C-parity odd and chiral odd combinations of t-channel exchange quantum numbers. In a hadronic ... More
SOFFER'S INEQUALITYJan 13 1995Various issues surrounding a recently proposed inequality among twist-two quark distributions in the nucleon are discussed. We provide a rigorous derivation of the inequality in QCD, including radiative corrections and scale dependence. We also give a ... More
Probing Quark Fragmentation Functions for Spin-1/2 Baryon Production in Unpolarized $e^+e^-$ AnnihilationOct 20 1994We study the measurement of the quark fragmentation functions for spin-1/2 baryon production ($\Lambda$ and $\bar \Lambda$, in particular) in unpolarized $e^+e^-$ annihilation. The spin-dependent fragmentation functions $\hat g_1(z)$ and $\hat h_1(z)$ ... More
$π^o$ Electroproduction and TransversityDec 14 2007Exclusive $\pi^o$ electroproduction and related processes are suggested to investigate the chiral odd transversity distributions of quarks in the transversely polarized nucleon, $h_1(x)$, and its first moment, the tensor charge. The connection between ... More
Flexible Parametrization of Generalized Parton Distributions from Deeply Virtual Compton Scattering ObservablesDec 16 2010Feb 16 2011We present a physically motivated parametrization of the chiral-even generalized parton distributions in the non-singlet sector obtained from a global analysis using a set of available experimental data. Our analysis is valid in the kinematical region ... More
Partonic Picture of Generalized Transverse Momentum DistributionsSep 26 2013We argue that due to parity constraints, the helicity combination of the purely momentum space counterparts of the Wigner distributions -- the generalized transverse momentum distributions -- that describes the configuration of an unpolarized quark in ... More
Identification of Observables for Quark and Gluon Orbital Angular MomentumDec 01 2014A new debate has recently arisen on the subject of orbital angular momentum in QCD, in particular on its observability and on its partonic interpretation. Orbital momentum can be defined in QCD using two different decomposition schemes that yield a kinetic ... More
On the Observability of the Quark Orbital Angular Momentum DistributionOct 18 2013Mar 18 2014We argue that due to Parity constraints, the helicity combination of the purely momentum space counterparts of the Wigner distributions -- the generalized transverse momentum distributions -- that describes the configuration of an unpolarized quark in ... More
Extraction of Generalized Parton Distribution Observables from Deeply Virtual Electron Proton Scattering ExperimentsMar 13 2019We provide the general expression of the cross section for exclusive deeply virtual photon electroproduction from a spin 1/2 target using current parameterizations of the off-forward correlation function in a nucleon for different beam and target polarization ... More
Problems with Fitting to the Power-Law DistributionFeb 11 2004Aug 13 2004This short communication uses a simple experiment to show that fitting to a power law distribution by using graphical methods based on linear fit on the log-log scale is biased and inaccurate. It shows that using maximum likelihood estimation (MLE) is ... More
A Group-Based Yule Model for Bipartite Author-Paper NetworksSep 08 2004This paper presents a novel model for author-paper networks, which is based on the assumption that authors are organized into groups and that, for each research topic, the number of papers published by a group is based on a success-breeds-success model. ... More
A Review Essay: "Lise Meitner and the Dawn of the Nuclear Age", by Patricia RifeJul 05 2000The recently published book, ``Lise Meitner and the Dawn of the Nuclear Age'', by Patricia Rife (Boston: Birkh\"{a}user, 1999) is reviewed in an essay for the lay audience. Meitner was a leading nuclear physicist at the time that the nucleus was the most ... More
Dick Dalitz: Examples of His Contributions to Particle PhysicsApr 30 2007Dick Dalitz produced lasting contributions to particle physics for 50 years. Along with Dalitz pairs, Dalitz plots and CDD poles, he did major work in parity violation, hyperon resonance identification, the quark model, and hypernuclei. These topics will ... More
Polarization of Inclusive $Λ_c$'s in a Hybrid ModelJan 18 2000A hybrid model is presented for hyperon polarization that is based on perturbative QCD subprocesses and the recombination of polarized quarks with scalar diquarks. The updated hybrid model is applied to $p+p\to \Lambda +X$ and successfully reproduces ... More
Polarization of inclusively produced $Λ_c$ in a QCD based hybrid modelJul 30 1999A hybrid model is presented for hadron polarization that is based on perturbative QCD subprocesses and the recombination of polarized quarks to form polarized hadrons. The model, originally applied to polarized $\Lambda$'s that were inclusively produced ... More
Spin Dependent Fragmentation Functions for Heavy Flavor Baryons and Single Heavy Hyperon PolarizationDec 04 2000Spin dependent fragmentation functions for heavy flavor quarks to fragment into heavy baryons are calculated in a quark-diquark model. The production of intermediate spin 1/2 and 3/2 excited states is explicity included. $\Lambda_b$ , $\Lambda_c$ and ... More
Spin Correlations in Top Quark Production and the Top Quark MassNov 12 1996Top-antitop quark pairs produced at the Tevatron have a sizeable spin correlation. That correlation feeds into the angular distribution of the decay products, particularly in the dilepton channel. Including the expected correlation in an overall analysis ... More
Dupin hypersurfaces in Lie sphere geometryMay 20 2014The method of moving frames in Lie sphere geometry has produced significant results in the classification of Dupin hypersurfaces in spheres. What is the secret of its effectiveness? The answer emerges in the classification of nonumbilic isoparametric ... More
Estimates of the Nucleon Tensor ChargeJun 15 2001Jun 18 2001Like the axial vector charges, defined from the forward nucleon matrix element of the axial vector current on the light cone, the nucleon tensor charge, defined from the corresponding matrix element of the tensor current, is essential for characterizing ... More
Hyperon Polarization, Transversity and LHC PhysicsDec 30 2011Jan 23 2012Longstanding puzzles in spin physics can be confronted at the high energies of the LHC. Will large s-quark and c-quark polarization be observed through heavy hyperon production? Top quarks are expected to have significant polarization - single spin asymmetries. ... More
Exclusive meson leptoproduction and spin dependent generalized parton distributionsAug 11 2010Exclusive meson leptoproduction from nucleons in the deeply virtual exchanged boson limit can be described by generalized parton distributions (GPDs). Including spin dependence in the description requires 8 independent quark-parton and gluon-parton functions. ... More
Accessing Generalized Transversity Distributions with Exclusive $π^o$ ElectroproductionAug 15 2009Exclusive $\pi^0$ electroproduction from nucleons at large $Q^2$ can be described by Generalized Parton Distributions (GPDs), particularly the chiral odd subset related to transversity. These GPDs can be accessed experimentally from various cross sections ... More
Antimicrobial resistance and use, and rates of hospitalization associated with bacterial infections, including sepsisMar 19 2018While the mechanisms and quantitative details are complex, few analysts would doubt that antibiotic use increases the prevalence of drug-resistant bacterial pathogens among all bacteria causing disease in a population. The causal connection between antibiotic ... More
Friedel oscillations in disordered quantum wires: Influence of e-e interactions on the localization lengthNov 08 2006The Friedel oscillations caused due to an impurity located at one edge of a disordered interacting quantum wire are calculated numerically. The electron density in the system's ground state is determined using the DMRG method, and the Friedel oscillations ... More
Driving a first order quantum phase transition by coupling a quantum dot to a 1D charge density waveOct 19 2006Feb 18 2007The ground state properties of a one-dimensional system with particle-hole symmetry, consisting of a gate controlled dot coupled to an interacting reservoir, are explored using the numerical DMRG method. It was previously shown that the system's thermodynamic ... More
Electromagnetic Polarizabilities and Charge Radii of the Nucleons in the Diquark-modelNov 05 1994Nov 09 1994The diquark model is used to calculate the electromagnetic polarizabilities and charge radii of the nucleons for three different potentials. Making the scalar diquark lower in mass introduces a mixing angle $\theta $ between the $\left| 56\right\rangle ... More
Top Quark Analysis in the Light Gluino ScenarioAug 19 1997The Fermilab top quark analysis is heavily dependent on the assumption of standard model backgrounds only. In the light gluino scenario, the stop quarks lie near the top in mass and their decays can influence the resulting top quark mass by an amount ... More
Exclusive Pion-production and the Relation to TransversityJul 15 2008Exclusive $\pi^0$ electroproduction from nucleons is suggested for extracting the tensor charge and other quantities related to transversity from experimental data. This process isolates C-parity odd and chiral odd combinations of t-channel exchange quantum ... More
An Alternative String Landscape Cosmology: Eliminating BizarrenessMay 14 2012Dec 13 2012In what has become a standard eternal inflation picture of the string landscape there are many problematic consequences and a difficulty defining probabilities for the occurrence of each type of universe. One feature in particular that might be philosophically ... More
Flavor-Spin Symmetry and the Tensor ChargeJan 27 2002Exploiting an approximate phenomenological symmetry of the $J^{PC}=1^{+-}$ light axial vector mesons and using pole dominance, we calculate the flavor contributions to the nucleon tensor charge. The result depends on the decay constants of the axial vector ... More
Pseudoscalar Meson Electroproduction and TranversitySep 03 2010Exclusive meson leptoproduction from nucleons in the deeply virtual exchanged boson limit can be described by generalized parton distributions (GPDs). Including spin dependence in the description requires 8 independent quark-parton and gluon-parton functions. ... More
Limitations on dispersion relations for Generalized Parton DistributionsAug 16 2009Deeply Virtual Compton Scattering and electroproduction of mesons involve amplitudes that are analytic in energy. Analyticity enables Dispersion Relations (DR's) for such amplitudes, relating real and imaginary parts. Lately it has been suggested that ... More
The Use of Dispersion Relations in Hard Exclusive Processes and the Partonic Interpretation of Deeply Virtual Compton ScatteringMay 28 2009Recently dispersion relations have been applied to hard exclusive processes such as deeply virtual Compton scattering, and a holographic principle was proposed that maps out the generalized parton distributions entering the soft matrix elements for the ... More
Probing Spin Dependent Parton Distributions though Deeply Virtual ProcessesOct 24 2015Spin and transverse momentum dependent parton distributions - Generalized Parton Distributions (GPDs) - are at the interface between the QCD structure of the hadrons and observable quantities. The GPDs are linear superpositions within helicity amplitudes. ... More
A Determination of the Nucleon Tensor ChargeNov 08 2001Exploiting an approximate phenomenological symmetry of the $J^{PC}=1^{+-}$ light axial vector mesons and using pole dominance, we calculate the flavor contributions to the nucleon tensor charge. The result depends on the decay constants of the axial vector ... More
Excited State Contributions to the Heavy Baryon Fragmentation Functions in a Quark-Diquark ModelSep 26 2000Spin dependent fragmentation functions for heavy flavor quarks to fragment into heavy baryons are calculated in a quark-diquark model. The production of intermediate spin 1/2 and 3/2 excited states is explicity included. The resulting $\Lambda_b$ production ... More
Einstein's Equations and a Cosmology with Finite MatterNov 21 2014Apr 25 2015We discuss various space-time metrics which are compatible with Einstein's equations and a previously suggested cosmology with a finite total mass. In this alternative cosmology the matter density was postulated to be a spatial delta function at the time ... More
Partonic Interpretation of Generalized Parton DistributionsJun 01 2010Jun 08 2010Generalized Parton Distributions describe, within QCD factorization, the non perturbative component in the amplitudes for deeply virtual exclusive processes. However, in order for a partonic interpretation to hold, semi-disconnected diagrams should not ... More
Investigating Partons' Transverse Spin with Deep Inelastic Exclusive ExperimentsApr 29 2011We show how deeply virtual pseudoscalar meson production experiments single out the contribution of the four chiral odd quark-proton GPDs which are related to the so far elusive transversity distribution function, $h_1$. Furthermore, in the kinematical ... More
Exclusive Meson Electroproduction: GPDs, Regge and Dispersion RelationsApr 20 2009Exclusive pi0 electroproduction from nucleons at large photon virtuality can be described in terms of Generalized Parton Distributions, particularly the chiral odd subset. Chiral odd GPDs are related to transversity and can be accessed experimentally ... More
The Chiral Odd Nucleon Tensor ChargeNov 21 2001Exploiting the phenomenological symmetry of the $J^{PC}=1^{+-}$ light axial vector mesons and using pole dominance, we calculate the flavor contributions to the nucleon tensor charge.
Transversity and Meson PhotoproductionSep 09 2002Sep 17 2002Both meson photoproduction and semi-inclusive deep inelastic scattering can potentially probe transversity in the nucleon. We explore how that potential can be realized dynamically. The role of rescattering in both exclusive and inclusive meson production ... More
Flavor-Spin Symmetry Estimate of the Nucleon Tensor ChargeJul 16 2001The axial vector and tensor charge, defined as the first moments of the forward nucleon matrix elements of corresponding quark currents, are essential for characterizing the spin structure of the nucleon. However, the transversity distribution and thus ... More
Top Mass Analyses for the Reported Top-Antitop Production and Decay EventsJun 03 1995We have analyzed the available data on $p\bar{p}\,\rightarrow\, t\, \bar{t}$ followed by the decays ($t\rightarrow bW^{+},\: \bar{t}\rightarrow \bar{b}W^{-}$) which lead to $e^{\pm}\mu^{\mp}2 \mathrm{jets}$ or $l^{\pm}4 \mathrm{jets}$ configurations, ... More
Where is Top?Aug 26 1993Possibilities are discussed for determining the top quark mass $m_t$ from observations on the decay processes for top-antitop pairs produced in antiproton-proton collisions, assuming that the $t \to bW^+$ decay channel is dominant and much faster than ... More
Test of Analysis Method for Top-Antitop Production and Decay EventsFeb 04 1998We have carried out Monte Carlo calculations on two sets of randomly generated QCD events due to $p\bar{p} \to t \bar{t}$ with top mass $m_t = 170$ GeV, one set leading to $e^+e^-$ or $e^{\pm}\mu^{\mp}$ or $\mu^+\mu^-$ 2jets (dilepton) and the other leading ... More
Spin Dependent Fragmentation Functions For Baryons in a Diquark ModelDec 21 1996The perturbative QCD calculation of heavy quark fragmentation into a heavy meson is extended to predict fragmentation into heavy flavor baryons. This is accomplished by implementing the quark-diquark model of the baryons. Several diquark form factors ... More
$T$-Odd Effects in Unpolarized Drell-Yan ScatteringJun 14 2005We consider the leading twist $T$-odd contributions as the dominant source of the $\cos 2\phi$ azimuthal asymmetry in unpolarized $p\bar{p}\to \mu\mu^+ X$ dilepton production in Drell-Yan Scattering. This asymmetry contains information on the distribution ... More
Baryons and Mesons with BeautyMay 31 2007Recent experimental findings of several mesons and baryons with "beauty" and "charm" as flavors remind us of the days when strangeness was discovered, and how its inclusion led to SU(3)-flavor symmetry with enormous success in the classification of the ... More
Fragmentation Functions For Baryons in a Quark-Diquark ModelJun 24 1997A perturbative QCD calculation of heavy flavor quark fragmentation into heavy flavor baryons is developed along the lines of corresponding heavy meson models. The non-perturbative formation of the baryon is accomplished by implementing the quark-diquark ... More
Transversity Properties of Quarks and Hadrons in SIDIS and Drell-YanSep 27 2005We consider the leading twist $T$-odd contributions as the dominant source of the azimuthal and transverse single spin asymmetries in SIDIS and dilepton production in Drell-Yan Scattering. These asymmetries contain information on the distribution of quark ... More
Compact surfaces with no Bonnet mateMar 28 2017This note gives sufficient conditions (isothermic or totally nonisothermic) for an immersion of a compact surface to have no Bonnet mate.
Observational Limits on a Cold Distant Kuiper BeltSep 19 2002Almost all of the $>600$ known Kuiper belt objects (KBOs) have been discovered within 50 AU of the Sun. One possible explanation for the observed lack of KBOs beyond 50 AU is that the distant Kuiper belt is dynamically very cold, and thus thin enough ... More
The Edge of the Solar SystemNov 02 2000The population of the Kuiper Belt within 50 AU of the Sun has likely been severely depleted by gravitational perturbations from the giant planets, particularly Neptune. The density of Kuiper Belt objects is expected to be two orders of magnitude higher ... More
Reconstruction from projections using dynamics: Non-Stochastic CaseJan 04 2001The problem of determining three-dimensional density fields from single two-dimensional projections is hopelessly underdetermined without additional assumptions. While parameterized inversions are typically used to solve this problem, we present theoretical ... More
Angular momentum transport by heat-driven g-modes in slowly pulsating B starsDec 06 2017Motivated by recent interest in the phenomenon of waves transport in massive stars, we examine whether the heat-driven gravity (g) modes excited in slowly-pulsating B (SPB) stars can significantly modify the stars' internal rotation. We develop a formalism ... More
Electroweak Symmetry Breaking by Strong Dynamics and the Collider PhenomenologyJan 25 2002Feb 10 2002We discuss the possible signatures in the electroweak symmetry breaking sector by new strong dynamics at future hadron colliders such as the Tevatron upgrade, the LHC and VLHC, and $e^+e^-$ linear colliders. Examples include a heavy Higgs-like scalar ... More
Coupling of Active Motion and Advection Shapes Intracellular Cargo TransportJun 13 2012Intracellular cargo transport can arise from passive diffusion, active motor-driven transport along cytoskeletal filament networks, and passive advection by fluid flows entrained by such motor/cargo motion. Active and advective transport are thus intrinsically ... More
Exact Solution of the F-TASEPApr 17 2019Apr 21 2019We obtain the exact solution of the facilitated totally asymmetric simple exclusion process (F-TASEP) in 1D. The model is closely related to the conserved lattice gas (CLG) model and to some cellular automaton traffic models. In the F-TASEP a particle ... More
Front Propagation in the Pearling Instability of Tubular VesiclesOct 17 1995Recently Bar-Ziv and Moses discovered a dynamical shape transformation induced in cylindrical lipid bilayer vesicles by the action of laser tweezers. We develop a hydrodynamic theory of fluid bilayers in interaction with the surrounding water and argue ... More
Exact Solution of the F-TASEPApr 17 2019We obtain the exact solution of the facilitated totally asymmetric simple exclusion process (F-TASEP) in 1D. The model is closely related to the conserved lattice gas (CLG) model and to some cellular automaton traffic models. In the F-TASEP a particle ... More
Flexible Parametrization of Generalized Parton Distributions: The Chiral-Odd SectorNov 03 2013Dec 04 2014We present a physically motivated parameterization of the chiral-odd generalized parton distributions. The parametrization is an extension of our previous one in the chiral-even sector which was based on the reggeized diquark model. While for chiral even ... More
Dynamical Topology Change in M TheoryOct 24 2000We study topology change in M theory compactifications on Calabi-Yau three-folds in the presence of G flux (the four form field strength). In particular, we discuss vacuum solutions in strongly coupled heterotic string theory in which the topology change ... More
A New Approach to Output-Sensitive Voronoi Diagrams and Delaunay TriangulationsDec 20 2012Apr 02 2013We describe a new algorithm for computing the Voronoi diagram of a set of $n$ points in constant-dimensional Euclidean space. The running time of our algorithm is $O(f \log n \log \Delta)$ where $f$ is the output complexity of the Voronoi diagram and ... More
Discrete Newtonian Cosmology: PerturbationsSep 01 2014In a previous paper [arXiv:1308.1852] we showed how a finite system of discrete particles interacting with each other via Newtonian gravitational attraction would lead to precisely the same dynamical equations for homothetic motion as in the case of the ... More
On the Hagedorn Behaviour of PP-wave Strings and N=4 SYM Theory at Finite R-Charge DensityAug 22 2002Nov 21 2003We discuss the high temperature behaviour of IIB strings in the maximally symmetric plane wave background, and show that there is a Hagedorn temperature. We discuss the map between strings in the pp-wave background and the dual superconformal field theory ... More
The geometric Cauchy problem for the membrane shape equationJun 23 2014Oct 06 2014We address the geometric Cauchy problem for surfaces associated to the membrane shape equation describing equilibrium configurations of vesicles formed by lipid bilayers. This is the Euler-Lagrange equation of the Canham-Helfrich-Evans elastic curvature ... More
$L^1$ bounds in normal approximationOct 17 2007The zero bias distribution $W^*$ of $W$, defined though the characterizing equation $\mathit{EW}f(W)=\sigma^2Ef'(W^*)$ for all smooth functions $f$, exists for all $W$ with mean zero and finite variance $\sigma^2$. For $W$ and $W^*$ defined on the same ... More
Normal approximation for hierarchical structuresMar 24 2005Given F:[a,b]^k\to [a,b] and a nonconstant X_0 with P(X_0\in [a,b])=1, define the hierarchical sequence of random variables {X_n}_{n\ge 0} by X_{n+1}=F(X_{n,1},...,X_{n,k}), where X_{n,i} are i.i.d. as X_n. Such sequences arise from hierarchical structures ... More
Non asymptotic distributional bounds for the Dickman Approximation of the running time of the Quickselect algorithmMar 01 2017Oct 19 2018Given a non-negative random variable $W$ and $\theta>0$, let the generalized Dickman transformation map the distribution of $W$ to that of $$ W^*=_d U^{1/\theta}(W+1), $$ where $U \sim {\cal U}[0,1]$, a uniformly distributed variable on the unit interval, ... More
On Observing Top Quark Production at the TevatronMay 30 1992May 30 1992A technique for separating top quark production from Standard Model background events is introduced. It is applicable to the channel in which one top quark decays semi-leptonically and its anti-quark decays hadronically into three jets, or vice versa. ... More
Flavor Dependence of T-odd PDFsAug 20 2007The flavor dependence of the naive time reversal odd (``T-odd'') parton distributions for $u$- and $d$-quarks are explored in the spectator model. The flavor dependence of $h_{1}^{\perp}$ is of significance for the analysis of the azimuthal $\cos(2\phi)$ ... More
Nucleon Transversity Properties Through ep ScatteringSep 12 2003The T-odd distribution functions contributing to transversity properties of the nucleon and their role in fueling nontrivial contributions to azimuthal asymmetries in semi-inclusive deep inelastic scattering are investigated. We use a dynamical model ... More
Novel Transversity Properties in Semi-Inclusive Deep Inelastic ScatteringJan 05 2003Mar 05 2003The $T$-odd distribution functions contributing to transversity properties of the nucleon and their role in fueling nontrivial contributions to azimuthal asymmetries in semi-inclusive deep inelastic scattering are investigated. We use a dynamical model ... More
Novel Transversity Properties in SIDISOct 28 2003We consider a rescattering mechanism to calculate a leading twist $T$-odd pion fragmentation function, a candidate for filtering the transversity properties of the nucleon. We evaluate the single spin azimuthal asymmetry for a transversely polarized target ... More
Quantum ModelingOct 04 2003We present a modification of Simon's algorithm that in some cases is able to fit experimentally obtained data to appropriately chosen trial functions with high probability. Modulo constants pertaining to the reliability and probability of success of the ... More
Dissipation-induced topological insulators: A no-go theorem and a recipeOct 29 2018Nonequilibrium conditions are traditionally seen as detrimental to the appearance of quantum-coherent many-body phenomena, and much effort is often devoted to their elimination. Recently this approach has changed: It has been realized that driven-dissipative ... More
Collins fragmentation function for pions and kaons in a spectator modelJul 23 2007We calculate the Collins fragmentation function in the framework of a spectator model with pseudoscalar pion-quark coupling and a Gaussian form factor at the vertex. We determine the model parameters by fitting the unpolarized fragmentation function for ... More
Transverse Quark Spin Effects and the Flavor Dependence of the Boer-Mulders FunctionAug 02 2007Apr 01 2008The naive time reversal odd (``T-odd'') parton distribution $h_{1}^{\perp}$, the so-called Boer-Mulders function, for both up ($u$) and down ($d$) quarks is considered in the diquark spectator model. While the results of different articles in the literature ... More
A mechanism for the T-odd pion fragmentation functionJul 10 2003Sep 11 2003We consider a simple rescattering mechanism to calculate a leading twist $T$-odd pion fragmentation function, a favored candidate for filtering the transversity properties of the nucleon. We evaluate the single spin azimuthal asymmetry for a transversely ... More
Novel Azimuthal Asymmetries in Drell Yan and Semi-inclusive Deep Inelastic ScatteringNov 16 2004We consider the leading and sub-leading twist $T$-odd and even contributions to the $\cos 2\phi$ azimuthal asymmetry in unpolarized dilepton production in Drell-Yan Scattering. We estimate the contributions' effects at $500 {\rm GeV}$, $ 50 {\rm GeV}$, ... More
Observations of Chiral Odd GPDs and their ImplicationsSep 28 2013Our original suggestion to investigate exclusive $\pi^0$ electroproduction as a method for extracting the tensor charge, transversity, and other quantities related to chiral odd generalized parton distributions from cross section and asymmetry data is ... More
Transversity in Exclusive and Inclusive ProcessesNov 11 2002Both meson photoproduction and semi-inclusive deep inelastic scattering can potentially probe transversity properties of the nucleon. We explore how that potential can be realized dynamically. The role of rescattering in both exclusive and inclusive meson ... More
Angular momentum sum rule for spin one hadronic systemsJan 03 2011Mar 05 2012We derive a sum rule for the total quark angular momentum of a spin-one hadronic system within a gauge invariant decomposition of the hadron's spin. We show that the total angular momentum can be measured through deeply virtual Compton scattering experiments ... More
Deeply Virtual Neutrino Production of $π^0$ from Nucleon and Nuclear TargetsNov 02 2009In most experiments aimed at determining the masses and mixing parameters for neutrino oscillations in different energy regimes there are strong backgrounds to neutrino interactions with matter that can confuse the expected small signals. One particular ... More
Flavor dependence of chiral odd generalized parton distributions and the tensor charge from the analysis of combined $π^0$ and $η$ exclusive electroproduction dataJan 02 2014Using a physically motivated parameterization based on the reggeized diquark model we perform a flavor separation of the chiral-odd generalized parton distributions obtained from both $\pi^0$ and $\eta$ exclusive electroproduction. In our approach we ... More
Easy as $π^o$: On the Interpretation of Recent Electroproduction ResultsJan 29 2012Jul 02 2012Exclusive $\pi^o$ electroproduction from nucleons was first suggested by Ahmad, Goldstein and Liuti for extracting from experimental data the tensor charge, transversity and other quantities related to chiral odd combinations of generalized parton distributions. ... More
A Primal-Dual Method for Optimal Control and Trajectory Generation in High-Dimensional SystemsDec 21 2017Jun 13 2018Presented is a method for efficient computation of the Hamilton-Jacobi (HJ) equation for time-optimal control problems using the generalized Hopf formula. Typically, numerical methods to solve the HJ equation rely on a discrete grid of the solution space ... More
Metrics for Explainable AI: Challenges and ProspectsDec 11 2018Feb 01 2019The question addressed in this paper is: If we present to a user an AI system that explains how it works, how do we know whether the explanation works and the user has achieved a pragmatic understanding of the AI? In other words, how do we know that an ... More
Liquid Nanodroplets Spreading on Chemically Patterned SurfacesNov 29 2005Controlling the spatial distribution of liquid droplets on surfaces via surface energy patterning can be used to control material delivery to specified regions via selective liquid/solid wetting. While studies of the equilibrium shape of liquid droplets ... More
Surface Wetting of Liquid NanodropletsOct 08 2004May 05 2005The spreading of liquid nanodroplets of different initial radii $R_{0}$ is studied using molecular dynamics simulation. Results for two distinct systems, Pb on Cu(111), which is non-wetting, and a coarse grained polymer model, which wets the surface, ... More
Spreading Dynamics of Polymer Nanodroplets in Cylindrical GeometriesApr 06 2004The spreading of one- and two-component polymer nanodroplets is studied using molecular dynamics simulation in a cylindrical geometry. The droplets consist of polymer chains of length 10, 40, and 100 monomers per chain described by the bead-spring model ... More
Spreading Dynamics of Polymer NanodropletsAug 08 2003The spreading of polymer droplets is studied using molecular dynamics simulations. To study the dynamics of both the precursor foot and the bulk droplet, large drops of ~200,000 monomers are simulated using a bead-spring model for polymers of chain length ... More
The Local Environment of the FUor-like Objects AR 6A and 6BJul 31 2008We present new 12CO J=3-2 and HCN J=3-2 molecular line maps of the region surrounding the young star AR 6 using the 15 metre James Clerk Maxwell Telescope. AR 6 was previously found to be a double source with both components exhibiting several characteristics ... More
On a lower bound for the Laplacian eigenvalues of a graphJul 11 2017Jul 26 2017If $\mu_m$ and $d_m$ denote, respectively, the $m$-th largest Laplacian eigenvalue and the $m$-th largest vertex degree of a graph, then $\mu_m \geqslant d_m-m+2$. This inequality was conjectured by Guo in 2007 and proved by Brouwer and Haemers in 2008. ... More
Universailty of Low Energy Absorption Cross-sections for Black HolesSep 06 1996In this paper we compute the low energy absorption cross-section for minimally coupled massles scalars and spin-$1/2$ particles, into a general spherically symmetric black hole in arbitrary dimensions. The scalars have a cross section equal to the area ... More
Anisotropic Agglomerative Adaptive Mean-ShiftNov 15 2014Mean Shift today, is widely used for mode detection and clustering. The technique though, is challenged in practice due to assumptions of isotropicity and homoscedasticity. We present an adaptive Mean Shift methodology that allows for full anisotropic ... More
Gaussian process emulation for discontinuous response surfaces with applications for cardiac electrophysiology modelsMay 25 2018Mathematical models of biological systems are beginning to be used for safety-critical applications, where large numbers of repeated model evaluations are required to perform uncertainty quantification and sensitivity analysis. Most of these models are ... More