Results for "Tyson B. Littenberg"

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A detection pipeline for galactic binaries in LISA dataJun 30 2011The Galaxy is suspected to contain hundreds of millions of binary white dwarf systems, a large fraction of which will have sufficiently small orbital period to emit gravitational radiation in band for space-based gravitational wave detectors such as the ... More
BayesLine: Bayesian Inference for Spectral Estimation of Gravitational Wave Detector NoiseOct 14 2014Gravitational wave data from ground-based detectors is dominated by instrument noise. Signals will be comparatively weak, and our understanding of the noise will influence detection confidence and signal characterization. Mis-modeled noise can produce ... More
Binary White Dwarfs as Laboratories for Extreme Gravity with LISANov 02 2018The observation of low-frequency gravitational waves with the Laser Interferometer Space Antenna will allow the study of new sources of gravitational radiation that are not accessible by ground-based instruments. Gravitational wave sources provide invaluable ... More
A Bayesian Approach to the Detection Problem in Gravitational Wave AstronomyFeb 02 2009Jul 16 2009The analysis of data from gravitational wave detectors can be divided into three phases: search, characterization, and evaluation. The evaluation of the detection - determining whether a candidate event is astrophysical in origin or some artifact created ... More
Separating Gravitational Wave Signals from Instrument ArtifactsAug 09 2010Central to the gravitational wave detection problem is the challenge of separating features in the data produced by astrophysical sources from features produced by the detector. Matched filtering provides an optimal solution for Gaussian noise, but in ... More
Tests of Bayesian Model Selection Techniques for Gravitational Wave AstronomyApr 13 2007Nov 08 2007The analysis of gravitational wave data involves many model selection problems. The most important example is the detection problem of selecting between the data being consistent with instrument noise alone, or instrument noise and a gravitational wave ... More
BayesWave: Bayesian Inference for Gravitational Wave Bursts and Instrument GlitchesOct 14 2014May 07 2015A central challenge in Gravitational Wave Astronomy is identifying weak signals in the presence of non-stationary and non-Gaussian noise. The separation of gravitational wave signals from noise requires good models for both. When accurate signal models ... More
Rapid gravitational wave parameter estimation with a single spin: Systematic uncertainties in parameter estimation with the SpinTaylorF2 approximationJun 19 2015Reliable low-latency gravitational wave parameter estimation is essential to target limited electromagnetic followup facilities toward astrophysically interesting and electromagnetically relevant sources of gravitational waves. In this study, we examine ... More
Systematic errors in low latency gravitational wave parameter estimation impact electromagnetic follow-up observationsJan 11 2016Mar 01 2016Among the most eagerly anticipated opportunities made possible by Advanced LIGO/Virgo are multimessenger observations of compact mergers. Optical counterparts may be short-lived so rapid characterization of gravitational wave (GW) events is paramount ... More
Fortifying the characterization of binary mergers in LIGO dataJul 31 2013The study of compact binary in-spirals and mergers with gravitational wave observatories amounts to optimizing a theoretical description of the data to best reproduce the true detector output. While most of the research effort in gravitational wave data ... More
Updates to the Fermi GBM Targeted Sub-threshold Search in Preparation for the Third Observing Run of LIGO/VirgoMar 29 2019In this document, we detail the improvements made to the Fermi GBM targeted sub-threshold search for counterparts to LIGO/Virgo gravitational-wave triggers. We describe the implemented changes and compare the sensitivity of the O3 search to that of the ... More
Rare Kaon DecaysDec 19 2005Dec 20 2005Recent results in and future prospects for the study of rare kaon decays are reviewed.
Rare Kaon and Pion DecaysDec 04 2002Recent results on rare kaon and pion decays are reviewed and prospects for future experiments are discussed
Enabling high confidence detections of gravitational-wave burstsNov 27 2015With the advanced LIGO and Virgo detectors taking observations the detection of gravitational waves is expected within the next few years. Extracting astrophysical information from gravitational wave detections is a well-posed problem and thoroughly studied ... More
Work Function Characterization of the Directionally Solidified LaB6 VB2 EutecticMar 31 2018With its low work function and high mechanical strength, the LaB6/VB2 eutectic system is an interesting candidate for high performance thermionic emitters. For the development of device applications, it is important to understand the origin, value, and ... More
Mathematical Analysis and Dynamic Active Subspaces for a Long term model of HIVApr 15 2016Apr 18 2016Recently, a long-term model of HIV infection dynamics was developed to describe the entire time course of the disease. It consists of a large system of ODEs with many parameters, and is expensive to simulate. In the current paper, this model is analyzed ... More
Neutron stars versus black holes: probing the mass gap with LIGO/VirgoMar 11 2015Jun 16 2015Inspirals and mergers of black hole (BHs) and/or neutron star (NSs) binaries are expected to be abundant sources for ground-based gravitational-wave (GW) detectors. We assess the capabilities of Advanced LIGO and Virgo to measure component masses using ... More
Systematic biases in parameter estimation of binary black-hole mergersOct 02 2012Parameter estimation of binary-black-hole merger events in gravitational-wave data relies on matched-filtering techniques, which, in turn, depend on accurate model waveforms. Here we characterize the systematic biases introduced in measuring astrophysical ... More
Prospects for observing ultra-compact binaries with space-based gravitational wave interferometers and optical telescopesJul 20 2012Aug 24 2012Space-based gravitational wave interferometers are sensitive to the galactic population of ultra-compact binaries. An important subset of the ultra-compact binary population are those stars that can be individually resolved by both gravitational wave ... More
An interesting class of Hankel determinantsJul 22 2018Oct 29 2018For small $r$ the Hankel determinants $d_r(n)$ of the sequence $\left({2n+r\choose n}\right)_{n\ge 0}$ are easy to guess and show an interesting modular pattern. For arbitrary $r$ and $n$ no closed formulae are known, but for each positive integer $r$ ... More
On the properties of the massive binary black hole merger GW170729Mar 15 2019Mar 20 2019We present a detailed investigation into the properties of GW170729, the gravitational wave with the most massive and distant source confirmed to date. We employ an extensive set of waveform models, including new improved models that incorporate the effect ... More
Astrophysical Model Selection in Gravitational Wave AstronomySep 27 2012Theoretical studies in gravitational wave astronomy have mostly focused on the information that can be extracted from individual detections, such as the mass of a binary system and its location in space. Here we consider how the information from multiple ... More
Leveraging waveform complexity for confident detection of gravitational wavesSep 21 2015Jan 12 2016The recent completion of Advanced LIGO suggests that gravitational waves (GWs) may soon be directly observed. Past searches for gravitational-wave transients have been impacted by transient noise artifacts, known as glitches, introduced into LIGO data ... More
Parameter estimation for gravitational-wave bursts with the BayesWave pipelineDec 06 2016Apr 10 2017We provide a comprehensive multi-aspect study on the performance of a pipeline used by the LIGO-Virgo Collaboration for estimating parameters of gravitational-wave bursts. We add simulated signals with four different morphologies (sine-Gaussians, Gaussians, ... More
Systematic and statistical errors in a bayesian approach to the estimation of the neutron-star equation of state using advanced gravitational wave detectorsFeb 20 2014Advanced ground-based gravitational-wave detectors are capable of measuring tidal influences in binary neutron-star systems. In this work, we report on the statistical uncertainties in measuring tidal deformability with a full Bayesian parameter estimation ... More
Parameter estimation for gravitational-wave bursts with the BayesWave pipelineDec 06 2016We provide a comprehensive multi-aspect study on the performance of a pipeline used by the LIGO-Virgo Collaboration for estimating parameters of gravitational-wave bursts. We add simulated signals with four different morphologies (sine-Gaussians, Gaussians, ... More
Nature of the Structural Symmetries Associated with Hybrid Improper Ferroelectricity in Ca3X2O7Mar 18 2019May 16 2019In hybrid improper ferroelectric systems, polarization arises from the onset of successive nonpolar lattice modes. In this work, measurements and modeling were performed to determine the spatial symmetries of the phases involved in the transitions to ... More
Temperature Dependent Local Structure of LaFeAsO_{1-x}F_x: Probing the Bond CorrelationsMar 24 2009The local structure of the parent and doped LaFeAsO1-xFx (pnictide) compounds were studied by x-ray absorption spectroscopy. In the doped system, the Fe-As and Fe-Fe correlations are well modeled by an Einstein model with no low temperature anomalies. ... More
eLISA: Astrophysics and cosmology in the millihertz regimeJan 17 2012This document introduces the exciting and fundamentally new science and astronomy that the European New Gravitational Wave Observatory (NGO) mission (derived from the previous LISA proposal) will deliver. The mission (which we will refer to by its informal ... More
Mitigation of the instrumental noise transient in gravitational-wave data surrounding GW170817Aug 10 2018Oct 20 2018In the coming years gravitational-wave detectors will undergo a series of improvements, with an increase in their detection rate by about an order of magnitude. Routine detections of gravitational-wave signals promote novel astrophysical and fundamental ... More
Astro2020 Decadal Science White Paper: Gravitational Wave Survey of Galactic Ultra Compact BinariesMar 13 2019Ultra-compact binaries (UCBs) are systems containing compact or degenerate stars with orbital periods less than one hour. Tens of millions of UCBs are predicted to exist within theGalaxy emitting gravitational waves (GWs) at mHz frequencies. Combining ... More
Conformal graph directed Markov systems on Carnot groupsMay 04 2016We develop a comprehensive theory of conformal graph directed Markov systems in the non-Riemannian setting of Carnot groups equipped with a sub-Riemannian metric. In particular, we develop the thermodynamic formalism and show that, under natural hypotheses, ... More
Heisenberg quasiregular ellipticityOct 24 2016Following the Euclidean results of Varopoulos and Pankka--Rajala, we provide a necessary topological condition for a sub-Riemannian 3-manifold $M$ to admit a nonconstant quasiregular mapping from the sub-Riemannian Heisenberg group $\mathbb{H}$. As an ... More
Homotopy groups of spheres and Lipschitz homotopy groups of Heisenberg groupsJan 21 2013Nov 28 2013We provide a sufficient condition for the nontriviality of the Lipschitz homotopy group of the Heisenberg group, $\pi_m^{Lip}(H_n)$, in terms of properties of the classical homotopy group of the sphere, $\pi_m(S^n)$. As an application we provide a new ... More
Sub-Riemannian curvature and a Gauss-Bonnet theorem in the Heisenberg groupApr 01 2016We use a Riemannnian approximation scheme to define a notion of $\textit{sub-Riemannian Gaussian curvature}$ for a Euclidean $C^{2}$-smooth surface in the Heisenberg group $\mathbb{H}$ away from characteristic points, and a notion of $\textit{sub-Riemannian ... More
Distinguishing black-hole spin-orbit resonances by their gravitational wave signatures. II: Full parameter estimationJul 20 2015Feb 15 2016Gravitational waves from coalescing binary black holes encode the evolution of their spins prior to merger. In the post-Newtonian regime and on the precession timescale, this evolution has one of three morphologies, with the spins either librating around ... More
Basic Parameter Estimation of Binary Neutron Star Systems by the Advanced LIGO/Virgo NetworkSep 12 2013Feb 12 2014Within the next five years, it is expected that the Advanced LIGO/Virgo network will have reached a sensitivity sufficient to enable the routine detection of gravitational waves. Beyond the initial detection, the scientific promise of these instruments ... More
The Whole is Greater than the Sum of the Parts: Optimizing the Joint Science Return from LSST, Euclid and WFIRSTJan 30 2015Feb 19 2015The focus of this report is on the opportunities enabled by the combination of LSST, Euclid and WFIRST, the optical surveys that will be an essential part of the next decade's astronomy. The sum of these surveys has the potential to be significantly greater ... More
On the lack of density of Lipschitz mappings in Sobolev spaces with Heisenberg targetSep 21 2011May 29 2014We study the question: when are Lipschitz mappings dense in the Sobolev space $W^{1,p}(M,\mathbf{H}^n)$? Here $M$ denotes a compact Riemannian manifold with or without boundary, while $\mathbf{H}^n$ denotes the $n$th Heisenberg group equipped with a sub-Riemannian ... More
Cantor set arithmeticNov 23 2017Every element $u$ of $[0,1]$ can be written in the form $u=x^2y$, where $x,y$ are elements of the Cantor set $C$. In particular, every real number between zero and one is the product of three elements of the Cantor set. On the other hand the set of real ... More
Micrometeoroid Events in LISA PathfinderMay 07 2019The zodiacal dust complex, a population of dust and small particles that pervades the Solar System, provides important insight into the formation and dynamics of planets, comets, asteroids, and other bodies. Here we present a new set of data obtained ... More
Tests of General Relativity and Fundamental Physics with Space-based Gravitational Wave DetectorsMar 07 2019Low-frequency gravitational-wave astronomy can perform precision tests of general relativity and probe fundamental physics in a regime previously inaccessible. A space-based detector will be a formidable tool to explore gravity's role in the cosmos, potentially ... More
Gravity Spy: Integrating Advanced LIGO Detector Characterization, Machine Learning, and Citizen ScienceNov 14 2016Feb 28 2017(abridged for arXiv) With the first direct detection of gravitational waves, the Advanced Laser Interferometer Gravitational-wave Observatory (LIGO) has initiated a new field of astronomy by providing an alternate means of sensing the universe. The extreme ... More
A theorem on shifted Hankel determinantsMay 01 2019We prove a conjecture of Johann Cigler on shifted Hankel determinants.
Two-sided bounds on minimum-error quantum measurement, on the reversibility of quantum dynamics, and on the maximum overlap problem using directional iteratesJul 20 2009Jun 02 2010In a unified framework, we obtain two-sided estimates of the following quantities of interest in quantum information theory: 1.The minimum-error distinguishability of arbitrary ensembles of mixed quantum states. 2.The approximate reversibility of quantum ... More
Error rates of Belavkin weighted quantum measurements and a converse to Holevo's asymptotic optimality theoremJul 10 2009We compare several instances of pure-state Belavkin weighted square-root measurements from the standpoint of minimum-error discrimination of quantum states. The quadratically weighted measurement is proven superior to the so-called "pretty good measurement" ... More
Operator-Schmidt decomposition of the quantum Fourier transform on C^N1 tensor C^N2Oct 13 2002Apr 25 2003Operator-Schmidt decompositions of the quantum Fourier transform on C^N1 tensor C^N2 are computed for all N1, N2 > 1. The decomposition is shown to be completely degenerate when N1 is a factor of N2 and when N1>N2. The first known special case, N1=N2=2^n, ... More
Gravity Spy: Integrating Advanced LIGO Detector Characterization, Machine Learning, and Citizen ScienceNov 14 2016(abridged for arXiv) With the first direct detection of gravitational waves, the Advanced Laser Interferometer Gravitational-wave Observatory (LIGO) has initiated a new field of astronomy by providing an alternate means of sensing the universe. The extreme ... More
Estimates of non-optimality of quantum measurements and a simple iterative method for computing optimal measurementsFeb 03 2009Feb 14 2009We construct crude estimates for non-optimality of quantum measurements in terms of their violation of Holevo's simplified minimum-error optimality conditions. As an application, we show that a modification of Barnett and Croke's proof of the optimality ... More
Two-sided estimates of minimum-error distinguishability of mixed quantum states via generalized Holevo-Curlander boundsJul 13 2009We prove a concise factor-of-2 estimate for the failure rate of optimally distinguishing an arbitrary ensemble of mixed quantum states, generalizing work of Holevo [Theor. Probab. Appl. 23, 411 (1978)] and Curlander [Ph.D. Thesis, MIT, 1979]. A modification ... More
Acyclic embeddings of open Riemann surfaces into new examples of elliptic manifoldsJul 01 2011The geometric notion of ellipticity for complex manifolds was introduced by Gromov in his seminal 1989 paper on the Oka principle, and is a sufficient condition for a manifold to be Oka. In the current paper we present contributions to three open questions ... More
A strong Oka principle for embeddings of some planar domains into CxC*Nov 18 2010Gromov, in his seminal 1989 paper on the Oka principle, introduced the notion of an elliptic manifold and proved that every continuous map from a Stein manifold to an elliptic manifold is homotopic to a holomorphic map. We show that a much stronger Oka ... More
A soft Oka principle for proper holomorphic embeddings of open Riemann surfaces into $(\mathbb{C}^*)^2$Mar 26 2014May 06 2014Let $X$ be an open Riemann surface. We prove an Oka property on the approximation and interpolation of continuous maps $X \to (\mathbb{C}^*)^2$ by proper holomorphic embeddings, provided that we permit a smooth deformation of the complex structure on ... More
What we can learn from multi-band observations of black hole binariesMar 10 2019The LIGO/Virgo gravitational-wave (GW) interferometers have to-date detected ten merging black hole (BH) binaries, some with masses considerably larger than had been anticipated. Stellar-mass BH binaries at the high end of the observed mass range (with ... More
COSMOS : Hubble Space Telescope ObservationsDec 12 2006Feb 19 2007The Cosmic Evolution Survey (COSMOS) was initiated with an extensive allocation (590 orbits in Cycles 12-13) using the Hubble Space Telescope (HST) for high resolution imaging. Here we review the characteristics of the HST imaging with the Advanced Camera ... More
Report on the second Mock LISA Data ChallengeNov 16 2007The Mock LISA Data Challenges are a program to demonstrate LISA data-analysis capabilities and to encourage their development. Each round of challenges consists of several data sets containing simulated instrument noise and gravitational-wave sources ... More
Rare Kaon DecaysOct 18 2000The current status of the study of rare kaon decays is reviewed. Future prospects are discussed.
Weak Lensing Results from the 75 Square Degree CTIO SurveyOct 28 2002Dec 02 2002We measure seeing-corrected ellipticities for 2 x 10^6 galaxies with magnitude R<23 in 12 widely separated fields totalling 75 deg^2 of sky. At angular scales >30\arcmin, ellipticity correlations are detected at high significance and exhibit nearly the ... More
BNL Future PlansFeb 18 1998I discuss the prospects for a fixed target physics program at the AGS in the RHIC era.
Rare K decay: results and prospectsJan 17 2002Recent results on rare kaon decays are reviewed and prospects for future experiments are discussed.
Polar State in Freestanding Strontium Titanate NanoparticlesAug 06 2014Aug 27 2014Monodispersed strontium titanate nanoparticles were prepared and studied in detail. It is found that ~10 nm as-prepared stoichiometric nanoparticles are in a polar structural state (with possibly ferroelectric properties) over a broad temperature range. ... More
Conference summary: Workshop on Precision Astronomy with Fully Depleted CCDs (2014)Jun 22 2015Thick fully depleted CCDs, while enabling wide spectral response, also present challenges in understanding the systematic errors due to 3D charge transport. This 2014 Workshop on Precision Astronomy with Fully Depleted CCDs covered progress that has been ... More
Galaxy-Mass Correlations on 10 Mpc Scales in the Deep Lens SurveyAug 19 2012We examine the projected correlation of galaxies with mass from small scales (<few hundred kpc) where individual dark matter halos dominate, out to 15 Mpc where correlated large-scale structure dominates. We investigate these profiles as a function of ... More
Tomographic Magnification of Lyman Break Galaxies in The Deep Lens SurveyApr 12 2012Sep 13 2012Using about 450,000 galaxies in the Deep Lens Survey, we present a detection of the gravitational magnification of z > 4 Lyman Break Galaxies by massive foreground galaxies with 0.4 < z < 1.0, grouped by redshift. The magnification signal is detected ... More
Operator-Schmidt decompositions and the Fourier transform, with applications to the operator-Schmidt numbers of unitariesJun 22 2003Jul 01 2003The operator-Schmidt decomposition is useful in quantum information theory for quantifying the nonlocality of bipartite unitary operations. We construct a family of unitary operators on C^n tensor C^n whose operator-Schmidt decompositions are computed ... More
Proper holomorphic immersions in homotopy classes of maps from finitely connected planar domains into CxC*Sep 20 2012Oct 24 2012Gromov, in his seminal 1989 paper on the Oka principle, proved that every continuous map from a Stein manifold into an elliptic manifold is homotopic to a holomorphic map. Previously we have shown that, given a continuous map $X \to \C\times\C^*$ from ... More
The Complexity of Planar Boolean #CSP with Complex WeightsDec 11 2012Aug 06 2013We prove a complexity dichotomy theorem for symmetric complex-weighted Boolean #CSP when the constraint graph of the input must be planar. The problems that are #P-hard over general graphs but tractable over planar graphs are precisely those with a holographic ... More
Optical Synoptic Telescopes: New Science FrontiersSep 12 2010Over the past decade, sky surveys such as the Sloan Digital Sky Survey have proven the power of large data sets for answering fundamental astrophysical questions. This observational progress, based on a synergy of advances in telescope construction, detectors, ... More
Superposition of fundamental solutions of second order quasilinear equationsOct 04 2016We prove a superposition principle in the spirit of Crandall-Zhang and Lindqvist-Manfredi for a class of second order quasilinear equations. Riesz potentials of nonnegative and compactly supported continuous functions are either subsolutions or supersolutions ... More
Oka properties of ball complementsMar 09 2013Mar 29 2017Let $n>1$ be an integer. We prove that holomorphic maps from Stein manifolds $X$ of dimension $<n$ to the complement $\mathbb{C}^n\setminus L$ of a compact convex set $L\subset\mathbb{C}^n$ satisfy the basic Oka property with approximation and interpolation. ... More
On the properties of the massive binary black hole merger GW170729Mar 15 2019We present a detailed investigation into the properties of GW170729, the gravitational wave with the most massive and distant source confirmed to date. We employ an extensive set of waveform models, including new improved models that incorporate the effect ... More
Riesz potentials and p-superharmonic functions in Lie groups of Heisenberg typeMay 21 2010We prove a superposition principle for Riesz potentials of nonnegative continuous functions on Lie groups of Heisenberg type. More precisely, we show that the Riesz potential $$ R_\alpha(\rho)(g) = \int_{\G} N(g^{-1} g')^{\alpha-Q} \rho(g') dg', \qquad ... More
Oka properties of ball complementsMar 09 2013Jun 09 2015Let $n>1$ be an integer. We prove that holomorphic maps from Stein manifolds $X$ of dimension $<n$ to the complement $\mathbb{C}^n\setminus L$ of a compact convex set $L\subset\mathbb{C}^n$ satisfy the basic Oka property with approximation and interpolation. ... More
Adaptive Mesh BooleansMay 05 2016We present a new method for performing Boolean operations on volumes represented as triangle meshes. In contrast to existing methods which treat meshes as 3D polyhedra and try to partition the faces at their exact intersection curves, we treat meshes ... More
The Case for Deep, Wide-Field CosmologyFeb 16 2009Feb 16 2009Much of the science case for the next generation of deep, wide-field optical/infrared surveys has been driven by the further study of dark energy. This is a laudable goal (and the subject of a companion white paper by Zhan et al.). However, one of the ... More
Robust parameter estimation for compact binaries with ground-based gravitational-wave observations using the LALInference software librarySep 25 2014Feb 16 2015The Advanced LIGO and Advanced Virgo gravitational wave (GW) detectors will begin operation in the coming years, with compact binary coalescence events a likely source for the first detections. The gravitational waveforms emitted directly encode information ... More
Marstrand's density theorem in the Heisenberg groupJul 24 2014We prove that if $\mu$ is a Radon measure on the Heisenberg group $\mathbb{H}^n$ such that the density $\Theta^s(\mu,\cdot)$, computed with respect to the Kor\'anyi metric $d_H$, exists and is positive and finite on a set of positive $\mu$ measure, then ... More
Bifurcation analysis of a model of the budding yeast cell cycleApr 05 2004We study the bifurcations of a set of nine nonlinear ordinary differential equations that describe the regulation of the cyclin-dependent kinase that triggers DNA synthesis and mitosis in the budding yeast, Saccharomyces cerevisiae. We show that Clb2-dependent ... More
Integral Curvature Representation and Matching Algorithms for Identification of Dolphins and WhalesAug 25 2017We address the problem of identifying individual cetaceans from images showing the trailing edge of their fins. Given the trailing edge from an unknown individual, we produce a ranking of known individuals from a database. The nicks and notches along ... More
Nature of the Structural Symmetries Associated with Hybrid Improper Ferroelectricity in Ca3X2O7Mar 18 2019In hybrid improper ferroelectric systems, polarization arises from the onset of successive nonpolar lattice modes. In this work, measurements and modeling were performed to determine the spatial symmetries of the phases involved in the transitions to ... More
Comparison of Domain Nucleation Mechanisms in a Minimal Model of Shoot Apical MeristemApr 15 2016Apr 19 2016Existing mathematical models of the shoot apical meristem (SAM) explain nucleation and confinement of a stem cell domain by Turing's mechanism, assuming that the diffusion coefficients of the activator (WUSCHEL) and inhibitor (CLAVATA) are significantly ... More
Turbulence near cyclic fold bifurcations in birhythmic mediaFeb 24 2004We show that at the onset of a cyclic fold bifurcation, a birhythmic medium composed of glycolytic oscillators displays turbulent dynamics. By computing the largest Lyapunov exponent, the spatial correlation function, and the average transient lifetime, ... More
Measurement of the Mass Profile of Abell 1689Apr 01 1995Apr 03 1995In this letter we present calibrated mass and light profiles of the rich cluster of galaxies Abell 1689 out to 1 $h^{-1}$ Mpc from the center. The high surface density of faint blue galaxies at high redshift, selected by their low surface brightness, ... More
Quantum compilation and circuit optimisation via energy dissipationNov 07 2018Dec 19 2018We describe a method for automatically recompiling a quantum circuit A into a target circuit B, with the goal that both circuits have the same action on a specific input i.e. A|in> = B|in>. This is of particular relevance to hybrid, NISQ-era algorithms ... More
The Mass distribution of the Most Luminous X-ray Cluster RXJ1347.5-1145 from Gravitational LensingMar 28 1997Galaxy cluster mass distribution are potentially useful probes of $\Omega_0$ and the nature of the dark matter. Large clusters will distort the observed shapes of background galaxies through gravitational lensing allowing the measurement of the cluster ... More
An unbiased metric of antiproliferative drug effect in vitroMay 22 2016In vitro cell proliferation assays are widely used in pharmacology, molecular biology, and drug discovery. Using theoretical modeling and experimentation, we show that current antiproliferative drug effect metrics suffer from time-dependent bias, leading ... More
Measurements and ab initio Molecular Dynamics Simulations of the High Temperature Ferroelectric Transition in Hexagonal RMnO3Oct 08 2011Measurements of the structure of hexagonal RMnO3 (R=rare earths (Ho) and Y) for temperatures significantly above the ferroelectric transition temperature (TFE) were conducted to determine the nature of the transition. The local and long range structural ... More
High Pressure Structural Stability of Multiferroic Hexagonal REMnO3Oct 04 2010May 03 2011Structural changes in REMnO3 (RE= Y, Ho, Lu) under high pressure were examined by synchrotron x-ray diffraction methods at room temperature. Compression occurs more readily in the ab plane than along the c-axis. Under hydrostatic pressure (~11 GPa), the ... More
Rare and Radiative Kaon DecaysMar 04 1993We review the status of theory and experiment of very rare and forbidden kaon decays. We then review the radiative non-leptonic decays, and the associated Dalitz pair modes. We pay particular attention to the study of long distance physics in radiative ... More
Probing the Fundamental Nature of Dark Matter with the Large Synoptic Survey TelescopeFeb 04 2019Apr 24 2019Astrophysical and cosmological observations currently provide the only robust, empirical measurements of dark matter. Future observations with Large Synoptic Survey Telescope (LSST) will provide necessary guidance for the experimental dark matter program. ... More
Cosmology with the Large Synoptic Survey Telescope: an OverviewJul 21 2017Mar 09 2018The Large Synoptic Survey Telescope (LSST) is a high etendue imaging facility that is being constructed atop Cerro Pachon in Northern Chile. It is scheduled to begin science operations in 2022. With an 8.4m (6.5m effective) aperture, a three-mirror design ... More
Removable sets for homogeneous linear PDE in Carnot groupsMay 23 2013Let $\cL$ be a homogeneous left invariant differential operator on a Carnot group. Assume that both $\cL$ and $\cL^t$ are hypoelliptic. We study the removable sets for $\cL$-solutions. We give precise conditions in terms of the Carnot--Carath\'eodory ... More
Pressure Effects on the Atomic and Electronic Structure of Aligned Small Diameter Carbon NanotubesMay 05 2008Aug 27 2008Density functional methods have been used to calculate the electronic properties of aligned smalldiameter single-walled carbon nanotubes under hydrostatic pressures. Abrupt pressure induced semiconductor-metal and metal-semiconductor transitions concomitant ... More
Correlations between pressure and bandwidth effects in metal-insulator transitions in manganitesOct 29 2003The effect of pressure on the metal-insulator transition in manganites with a broad range of bandwidths is investigated. A critical pressure is found at which the metal-insulator transition temperature, T$_{MI}$, reaches a maximum value in every sample ... More
Pressure Induced Reentrant Electronic and Magnetic State in Pr0.7Ca0.3MnO3 ManganiteJan 23 2003Sep 30 2003In Pr$_{0.7}$Ca$_{0.3}$MnO$_{3}$, pressure induces reentrant magnetic and electronic state changes in the range 1 atm to $\sim$ 6 GPa. The metal-insulator and magnetic transition temperatures coincide from $\sim$1 to 5 GPa, decouple outside of this range ... More
Pressure effects on charge, spin, and metal-insulator transitions in narrow bandwidth manganite Pr$_{1-x}$Ca$_{x}$MnO$_{3}$Nov 19 2003Dec 03 2003Pressure effects on the charge and spin states and the relation between the ferromagnetic and metallic states were explored on the small bandwidth manganite Pr$_{1-x}$Ca$_{x}$MnO$_{3}$ (x = 0.25, 0.3, 0.35). Under pressure, the charge ordering state is ... More
Low-frequency gravitational-wave science with eLISA/NGOFeb 03 2012Sep 12 2012We review the expected science performance of the New Gravitational-Wave Observatory (NGO, a.k.a. eLISA), a mission under study by the European Space Agency for launch in the early 2020s. eLISA will survey the low-frequency gravitational-wave sky (from ... More
The decays $K \to ππν\overlineν$ within the standard modelDec 23 1995Oct 15 1996We study the reactions $K \rightarrow \pi \pi \nu \overline{\nu}$ within the minimal standard model. We use isospin symmetry to relate the matrix elements to the form factors measured in $K_{\ell 4}$. We argue that these modes are short distance dominated ... More
Efficient Functional-Based Adaptation for CFD ApplicationsNov 06 2015Adjoint methods have gained popularity in recent years for driving adaptation procedures which aim to reduce error in solution functionals. While adjoint methods have been proven effective for functional-based adaptation, the practical implementation ... More
Dark Matter in the Galaxy Cluster CL J1226+3332 at Z=0.89Oct 03 2008We present a weak-lensing analysis of the galaxy cluster CL J1226+3332 at z=0.89 using Hubble Space Telescope Advanced Camera for Surveys images. The cluster is the hottest (>10 keV), most X-ray luminous system at z>0.6 known to date. The relaxed X-ray ... More