Results for "Jason A. Dittmann"

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Trigonometric Parallaxes for 1,507 Nearby Mid-to-Late M-dwarfsDec 11 2013The MEarth survey is a search for small rocky planets around the smallest, nearest stars to the Sun as identified by high proper motion with red colors. We augmented our planetary search time series with lower cadence astrometric imaging and obtained ... More
A Tentative Detection of a Starspot During Consecutive Transits of an Extrasolar Planet from the Ground: No Evidence of a Double Transiting Planet System Around TrES-1Jun 23 2009There have been numerous reports of anomalies during transits of the planet TrES-1b. Recently, Rabus and coworkers' analysis of HST observations lead them to claim brightening anomalies during transit might be caused by either a second transiting planet ... More
Calibration of the MEarth Photometric System: Optical Magnitudes and Photometric Metallicity Estimates for 1802 Nearby M-dwarfsOct 22 2015The MEarth Project is a photometric survey systematically searching the smallest stars nearest to the Sun for transiting rocky planets. Since 2008, MEarth has taken approximately two million images of 1844 stars suspected to be mid-to-late M dwarfs. We ... More
Connections and Metrics Respecting Standard PurificationJun 08 1998Standard purification interlaces Hermitian and Riemannian metrics on the space of density operators with metrics and connections on the purifying Hilbert-Schmidt space. We discuss connections and metrics which are well adopted to purification, and present ... More
An Activity-Rotation Relationship and Kinematic Analysis of Nearby Mid-to-Late-type M DwarfsSep 04 2015Using spectroscopic observations and photometric light curves of 238 nearby M dwarfs from the MEarth exoplanet transit survey, we examine the relationships between magnetic activity (quantified by H-alpha emission), rotation period, and stellar age. Previous ... More
A Spectroscopic Study of Type Ibc Supernova Host Galaxies from Untargeted SurveysJun 12 2012Sep 16 2012We present the largest spectroscopic study of the host environments of Type Ibc supernovae (SN Ibc) discovered exclusively by untargeted SN searches. Past studies of SN Ibc host environments have been biased towards high-mass, high-metallicity galaxies ... More
Effective Theories of ConfinementNov 21 2001We review some approaches to describe confinement in terms of effective (model) field theories. After a brief discussion of the dual Abelian Higgs model, we concentrate on a lattice analysis of the Faddeev-Niemi effective action conjectured to describe ... More
Four new eclipsing mid M-dwarf systems from the New Luyten Two Tenths catalogAug 09 2018Using data from the MEarth-North and MEarth-South transit surveys, we present the detection of eclipses in four mid M-dwarf systems: LP 107-25, LP 261-75, LP 796-24, and LP 991-15. Combining the MEarth photometry with spectroscopic follow-up observations, ... More
How to Constrain Your M dwarf II: the mass-luminosity-metallicity relation from 0.075 to 0.70$M_\odot$Nov 16 2018Jan 26 2019The mass-luminosity relation for late-type stars has long been a critical tool for estimating stellar masses. However, there is growing need for both a higher-precision relation and a better understanding of systematic effects (e.g., metallicity). Here ... More
On the Curvature of Monotone Metrics and a Conjecture Concerning the Kubo-Mori MetricJun 02 1999It is the aim of this article to determine curvature quantities of an arbitrary Riemannian monotone metric on the space of positive matrices resp. nonsingular density matrices. Special interest is focused on the scalar curvature due to its expected quantum ... More
Note on Explicit Formulae for the Bures MetricAug 24 1998The aim of this paper is to derive explicit formulae for the Riemannian Bures metric on the manifold of (finite dimensional) nondegenerate density matrices. The computation of the Bures metric using the presented equations does not require any diagonalization ... More
Defining Subrings in Finitely Generated Fields of Characteristic Not TwoOct 22 2018We give a construction of a family of definable subrings of finitely generated fields $K$ of characteristic not two. We deduce that for any such $K$ there exists a first-order sentence $\varphi_K$ characterising $K$ in the class of finitely generated ... More
Line Emission in AGN: Effects of Local Delays Upon Line VariabilityJun 04 1996Previous works concerning active galactic nuclei (AGN) variability (e.g., Blandford \& McKee 1982) have assumed that the emission characteristics of illuminated clouds are purely a function of the instant continuum flux to which they are exposed. This ... More
Line Emission from Stellar Winds in Active Galactic NucleiDec 01 1999This dissertation presents synthetic spectra and response functions of the red giant stellar line emission model of active galactic nuclei. Our results agree with the fundamental line emission characteristics of active galactic nuclei within the model ... More
Mass Function Gradients and the Need for Dark MatterFeb 16 1998Mar 05 1998There is substantial evidence that the initial mass function (IMF) may be a function of the local star formation conditions. In particular, the IMF is predicted to flatten with increasing local luminosity density, with the formation of massive stars being ... More
A temperate rocky super-Earth transiting a nearby cool starApr 18 2017M dwarf stars, which have masses less than 60 per cent that of the Sun, make up 75 per cent of the population of the stars in the Galaxy [1]. The atmospheres of orbiting Earth-sized planets are observationally accessible via transmission spectroscopy ... More
LSPM J1112+7626: detection of a 41-day M-dwarf eclipsing binary from the MEarth transit surveySep 09 2011We report the detection of eclipses in LSPM J1112+7626, which we find to be a moderately bright (I_C = 12.14 +/- 0.05) very low-mass binary system with an orbital period of 41.03236 +/- 0.00002 days, and component masses M_1 = 0.395 +/- 0.002 Msol and ... More
Efficient ray tracing on 3D regular grids for fast generation of digitally reconstructed radiographs in iterative tomographic reconstruction techniquesSep 04 2016Cone beam projection is an essential and particularly time consuming part of any iterative tomographic reconstruction algorithm. On current graphics hardware especially the amount and pattern of memory accesses is a limiting factor when read-only textures ... More
Irreducibility of Polynomials over Global Fields is DiophantineJan 28 2016Oct 19 2017Given a global field $K$ and a positive integer $n$, we present a diophantine criterion for a polynomial in one variable of degree $n$ over $K$ not to have any root in $K$. This strengthens the known result that the set of non-$n$-th-powers in $K$ is ... More
A 2 Earth Radius Planet Orbiting the Bright Nearby K-Dwarf Wolf 503Jun 09 2018Since its launch in 2009, the Kepler telescope has found thousands of planets with radii between that of Earth and Neptune. Recent studies of the distribution of these planets have revealed a rift in the population near 1.5-2.0$R_{\bigoplus}$, informally ... More
Stellar Flares from the First Tess Data Release: Exploring a New Sample of M-dwarfsJan 02 2019We perform a study of stellar flares for the 24,809 stars observed with 2 minute cadence during the first two months of the TESS mission. Flares may erode exoplanets' atmospheres and impact their habitability, but might also trigger the genesis of life ... More
Ultraproducts as a tool for first-order inexpressibility in the finite and infiniteOct 11 2013Ultraproducts are a well-known tool in the classical model theory of first-order logic. We explore their uses in the context of finite model theory.
Ionization by bulk heating of electrons in capacitive radio frequency atmospheric pressure microplasmasAug 31 2012May 31 2013Electron heating and ionization dynamics in capacitively coupled radio frequency (RF) atmospheric pressure microplasmas operated in helium are investigated by Particle in Cell simulations and semi-analytical modeling. A strong heating of electrons and ... More
Radiotherapy planning for glioblastoma based on a tumor growth model: Improving target volume delineationNov 22 2013Dec 19 2013Glioblastoma are known to infiltrate the brain parenchyma instead of forming a solid tumor mass with a defined boundary. Only the part of the tumor with high tumor cell density can be localized through imaging directly. In contrast, brain tissue infiltrated ... More
Finite-frequency noise of interacting single-electron emitters: spectroscopy with higher noise harmonicsMay 08 2018We derive the symmetrized current-noise spectrum of a quantum dot, which is weakly tunnel-coupled to an electron reservoir and driven by a slow time-dependent gate voltage. This setup can be operated as an on-demand emitter of single electrons into a ... More
Almost Global Existence for 4-Dimensional Quasilinear Wave Equations in Exterior DomainsFeb 20 2014This article focuses on almost global existence for quasilinear wave equations with small initial data in 4-dimensional exterior domains. The nonlinearity is allowed to depend on the solution at the quadratic level as well as its first and second derivatives. ... More
Dynamic Modeling of Nontargeted and Targeted Advertising Strategies in an OligopolyOct 27 2015With the growing collection of sales and marketing data and depth of detailed knowledge of consumer habits and trends, firms are gaining the capability to discern customers of other firms from the potential market of uncommitted consumers. Firms with ... More
A note on Fano manifolds whose second Chern character is positiveFeb 28 2006This note outlines some first steps in the classification of Fano manifolds for which $c_1^2-2c_2$ is positive or nef.
A TESS Dress Rehearsal: Planetary Candidates and Variables from K2 Campaign 17Jun 08 2018We produce light curves for all ~34,000 targets observed with K2 in Campaign 17 (C17), identifying 34 planet candidates, 184 eclipsing binaries, and 222 other periodic variables. The location of the C17 field means follow-up can begin immediately now ... More
A Missing-Link in the Supernova-GRB Connection: The Case of SN 2012apFeb 25 2014Apr 23 2015Gamma Ray Bursts (GRBs) are characterized by ultra-relativistic outflows, while supernovae are generally characterized by non-relativistic ejecta. GRB afterglows decelerate rapidly usually within days, because their low-mass ejecta rapidly sweep up a ... More
Dimension and rank for mapping class groupsDec 15 2005Jan 12 2007We study the large scale geometry of the mapping class group, MCG. Our main result is that for any asymptotic cone of MCG, the maximal dimension of locally compact subsets coincides with the maximal rank of free abelian subgroups of MCG. An application ... More
Imaging of Ultraluminous Infrared Galaxies in the Near-UVMay 08 2000We present the first ground-based U' (3410 angstroms) images of Ultraluminous Infrared Galaxies (ULIGs). Strong U' emission (median total M_U' = -20.8) is seen in all systems and in some cases the extended tidal features (both the smooth stellar distribution ... More
Calculations of Nonlinear Wave-Packet Interferometry Signals in the Pump-Probe Limit as Tests for Vibrational Control over Electronic Excitation TransferOct 12 2009The preceding paper describes a strategy for externally influencing the course of short-time electronic excitation transfer (EET) in molecular dimers and observing the process by nonlinear wave-packet interferometry (nl-WPI). Within a sample of isotropically ... More
Strong Electron Correlation in Nitrogenase Cofactor, FeMocoMay 22 2018FeMoco, MoFe$_7$S$_9$C, has been shown to be the active catalytic site for the reduction of nitrogen to ammonia in the nitrogenase protein. An understanding of its electronic structure including strong electron correlation is key to designing mimic catalysts ... More
Higher Fano manifolds and rational surfacesFeb 28 2006For a Fano manifold of pseudo-index at least 3 and $c_1^2-2c_2$ nef, we show irreducibility of certain spaces of curves on the Fano manifold implies the manifold is a union of rational surfaces.
Very twisting families of pointed lines on GrassmanniansFeb 28 2006There exist very twisting families of lines on Grassmannians and isotropic Grassmannians. This is a key step in proving existence of a rational section of a family of isotropic Grassmannians over a surface with vanishing Brauer obstruction.
Divisor classes and the virtual canonical bundle for genus 0 mapsFeb 28 2006Some divisor class relations are proved and used to compute the Cartier divisor class of the virtual canonical bundle for genus 0 maps to a smooth target.
A Wolf in Sheepskin: Extraordinary Supernova 2012au Veiled Behind Ordinary Radio EmissionSep 13 2013We present extensive radio and X-ray observations of SN\, 2012au, the energetic radio luminous supernova of type Ib that may be a link between subsets of hydrogen-poor superluminous and normal core-collapse supernovae. The observations closely follow ... More
A PRIMAL view of the Milky Way, made possible by Gaia and M2M modellingMar 05 2015We have developed our original made-to-measure (M2M) algorithm, PRIMAL, with the aim of modelling the Galactic disc from upcoming Gaia data. From a Milky Way like N-body disc galaxy simulation, we have created mock Gaia data using M0III stars as tracers, ... More
Ground states of the Wick-Cutkosky model using light-front dynamicsFeb 05 2000Mar 17 2000We consider the ground state in a model with scalar nucleons and a meson using the formalism of light-front dynamics. Light-front potentials for two-nucleon bound states are calculated using two approaches. First, light-front time-ordered perturbation ... More
Spontaneous Emergence of Spatio-Temporal Order in Class 4 AutomataApr 30 2005We report surprisingly regular behaviors observed for a class 4 cellular automaton, the totalistic rule 20: starting from disordered initial configurations the automaton produces patterns which are periodic not only in time but also in space. This is ... More
Switching between Limit Cycles in a Model of Running Using Exponentially Stabilizing Discrete Control Lyapunov FunctionJul 07 2018This paper considers the problem of switching between two periodic motions, also known as limit cycles, to create agile running motions. For each limit cycle, we use a control Lyapunov function to estimate the region of attraction at the apex of the flight ... More
Discovery probability of next-generation neutrinoless double-$β$ decay experimentsMay 08 2017Jul 21 2017The Bayesian discovery probability of future experiments searching for neutrinoless double-$\beta$ decay is evaluated under the popular assumption that neutrinos are their own antiparticles. A Bayesian global fit is performed to construct a probability ... More
Ruprecht 147: The oldest nearby open cluster as a new benchmark for stellar astrophysicsJun 27 2012Jan 05 2013Ruprecht 147 is a hitherto unappreciated open cluster that holds great promise as a standard in fundamental stellar astrophysics. We have conducted a radial velocity survey of astrometric candidates with Lick, Palomar, and MMT observatories and have identified ... More
Custom Chipset and Compact Module Design for a 75-110 GHz Laboratory Signal SourceJul 19 2016We report on the development and characterization of a compact, full-waveguide bandwidth (WR-10) signal source for general-purpose testing of mm-wave components. The MMIC-based multichip module is designed for compactness and ease-of-use, especially in ... More
Mathematical Morphology: Star/Galaxy Differentiation & Galaxy Morphology ClassificationNov 02 2006We present an application of Mathematical Morphology (MM) for the classification of astronomical objects, both for star/galaxy differentiation and galaxy morphology classification. We demonstrate that, for CCD images, 99.3 +/- 3.8 % of galaxies can be ... More
Transit Observations of the WASP-10 SystemMar 09 2010We present here observations of the transit of WASP-10b on 14 October 2009 UT taken from the University of Arizona's 1.55 meter Kuiper telescope on Mt. Bigelow. Conditions were photometric and accuracies of 2.0 mmag RMS were obtained throughout the transit. ... More
When to use 3D Die-Stacked Memory for Bandwidth-Constrained Big Data WorkloadsAug 26 2016Response time requirements for big data processing systems are shrinking. To meet this strict response time requirement, many big data systems store all or most of their data in main memory to reduce the access latency. Main memory capacities have grown, ... More
Frequency control in synchronized networks of inhibitory neuronsMar 20 1998We analyze the control of frequency for a synchronized inhibitory neuronal network. The analysis is done for a reduced membrane model with a biophysically-based synaptic influence. We argue that such a reduced model can quantitatively capture the frequency ... More
An Efficient Algorithm for Clustering of Large-Scale Mass Spectrometry DataJan 04 2013High-throughput spectrometers are capable of producing data sets containing thousands of spectra for a single biological sample. These data sets contain a substantial amount of redundancy from peptides that may get selected multiple times in a LC-MS/MS ... More
Mining Temporal Patterns from iTRAQ Mass Spectrometry(LC-MS/MS) DataApr 28 2011Large-scale proteomic analysis is emerging as a powerful technique in biology and relies heavily on data acquired by state-of-the-art mass spectrometers. As with any other field in Systems Biology, computational tools are required to deal with this ocean ... More
Perfect mirror transport protocol with higher dimensional quantum chainsJun 02 2008Jan 23 2009A globally controlled scheme for quantum transport is proposed. The scheme works on a 1D chain of nearest neighbor coupled systems of qudits (finite dimension), or qunats (continuous variable), taking any arbitrary initial quantum state of the chain and ... More
The Science Case for an Extended Spitzer MissionOct 11 2017Although the final observations of the Spitzer Warm Mission are currently scheduled for March 2019, it can continue operations through the end of the decade with no loss of photometric precision. As we will show, there is a strong science case for extending ... More
TESS Discovery of a Transiting Super-Earth in the $π$ Mensae SystemSep 16 2018Nov 08 2018We report the detection of a transiting planet around $\pi$ Mensae (HD 39091), using data from the Transiting Exoplanet Survey Satellite (TESS). The solar-type host star is unusually bright (V=5.7) and was already known to host a Jovian planet on a highly ... More
Follow-up Observations of the Neptune Mass Transiting Extrasolar Planet HAT-P-11bMay 07 2009Jun 18 2009We have confirmed the existence of the transiting super Neptune extrasolar planet HAT-P-11b. On May 1, 2009 UT the transit of HAT-P-11b was detected at the University of Arizona's 1.55m Kuiper Telescope with 1.7 millimag rms accuracy. We find a central ... More
The Impact of Stellar Rotation on the Detectability of Habitable Planets Around M DwarfsApr 11 2016Stellar activity and rotation frustrate the detection of exoplanets through the radial velocity technique. This effect is particularly of concern for M dwarfs, which can remain magnetically active for billions of years. We compile rotation periods for ... More
A Super-Earth and two sub-Neptunes transiting the bright, nearby, and quiet M-dwarf TOI-270Mar 14 2019We report the Transiting Exoplanet Survey Satellite (TESS) discovery of three small planets transiting one of the brightest (K-mag 8.3) and nearest (22.5 parsec) M-dwarf hosts to date, TOI-270 (TIC 259377017). The system is observationally favourable, ... More
On Bellman's principle with inequality constraintsNov 14 2011We consider an example by Haviv (1996) of a constrained Markov decision process that, in some sense, violates Bellman's principle. We resolve this issue by showing how to preserve a form of Bellman's principle that accounts for a change of constraint ... More
Long range forces between polar alkali diatoms aligned by external electric fieldsJul 15 2012Long range electrostatic, induction and dispersion coefficients including terms of order $R^{-8}$ have been calculated by the sum over states method using time dependent density functional theory. We also computed electrostatic moments and static polarizabilities ... More
Sensor Scheduling for Energy-Efficient Target Tracking in Sensor NetworksSep 15 2010In this paper we study the problem of tracking an object moving randomly through a network of wireless sensors. Our objective is to devise strategies for scheduling the sensors to optimize the tradeoff between tracking performance and energy consumption. ... More
Self-similarities in the frequency-amplitude space of a loss-modulated CO$_2$ laserMay 31 2005We show the standard two-level continuous-time model of loss-modulated CO$_2$ lasers to display the same regular network of self-similar stability islands known so far to be typically present only in discrete-time models based on mappings. For class B ... More
Embedded density functional theory for covalently bonded and strongly interacting subsystemsFeb 19 2011Embedded density functional theory (e-DFT) is used to describe the electronic structure of strongly interacting molecular subsystems. We present a general implementation of the Exact Embedding (EE) method [J. Chem. Phys. 133, 084103 (2010)] to calculate ... More
A Minimal SU(5) SuperGUT in Pure Gravity MediationFeb 25 2019The lack of evidence for low-scale supersymmetry suggests that the scale of supersymmetry breaking may be higher than originally anticipated. However, there remain many motivations for supersymmetry including gauge coupling unification and a stable dark ... More
On the Apparent Orbital Inclination Change of the Extrasolar Transiting Planet TrES-2bJul 09 2009Mar 13 2010On June 15, 2009 UT the transit of TrES-2b was detected using the University of Arizona's 1.55 meter Kuiper Telescope with 2.0-2.5 millimag RMS accuracy in the I-band. We find a central transit time of $T_c = 2454997.76286 \pm0.00035$ HJD, an orbital ... More
A Revised Orbital Ephemeris for HAT-P-9bJun 17 2010We present here three transit observations of HAT-P-9b taken on 14 February 2010, 18 February 2010, and 05 April 2010 UT from the University of Arizona's 1.55 meter Kuiper telescope on Mt. Bigelow. Our transit light curves were obtained in the I filter ... More
A Search for Additional Bodies in the GJ 1132 Planetary System from 21 Ground-based Transits and a 100 Hour Spitzer CampaignNov 29 2016We present the results of a search for additional bodies in the GJ 1132 system through two methods: photometric transits and transit timing variations of the known planet. We collected 21 transit observations of GJ 1132b with the MEarth-South array since ... More
Families of rationally simply connected varieties over surfaces and torsors for semisimple groupsSep 30 2008Under suitable hypotheses, we prove that a form of a projective homogeneous variety $G/P$ defined over the function field of a surface over an algebraically closed field has a rational point. The method uses an algebro-geometric analogue of simple connectedness ... More
Real-Root Preserving Differential Operator Representations of Orthogonal PolynomialsJul 17 2017In this paper, we study linear transformations of the form $T[x^n]=P_n(x)$ where $\{P_n(x)\}$ is an orthogonal polynomial system. Of particular interest is understanding when these operators preserve real-rootedness in polynomials. It is known that when ... More
CORRECT: Code Reviewer Recommendation in GitHub Based on Cross-Project and Technology ExperienceJul 09 2018Peer code review locates common coding rule violations and simple logical errors in the early phases of software development, and thus reduces overall cost. However, in GitHub, identifying an appropriate code reviewer for a pull request is a non-trivial ... More
Superfast solution of linear convolutional Volterra equations using QTT approximationNov 22 2012We address a linear fractional differential equation and develop effective solution methods using algorithms for inversion of triangular Toeplitz matrices and the recently proposed QTT format. The inverses of such matrices can be computed by the divide ... More
Quantum stabilization of 1/3-magnetization plateau in Cs_2CuBr_4Sep 22 2008We consider the phase diagram of a spatially anisotropic 2D triangular antiferromagnet in a magnetic field. Classically, the ground state is umbrella-like for all fields, but we show that the quantum phase diagram is much richer and contains a 1/3 magnetization ... More
Atmospheric Imaging Assembly Response Functions: Solving the Fe VIII Problems with Hinode EIS Bright Point DataJan 09 2013The Atmospheric Imaging Assembly (AIA) onboard the Solar Dynamics Observatory is a state-of-the-art imager with the potential to do unprecedented time-dependent multi-thermal analysis at every pixel on scales short compared to the radiative and conductive ... More
Coherence in scale-free networks of chaotic mapsJul 30 2004Nov 17 2004We study fully synchronized states in scale-free networks of chaotic logistic maps as a function of both dynamical and topological parameters. Three different network topologies are considered: (i) random scale-free topology, (ii) deterministic pseudo-fractal ... More
Reaction-controlled diffusion: Monte Carlo simulationsJun 01 2003Aug 19 2003We study the coupled two-species non-equilibrium reaction-controlled diffusion model introduced by Trimper et al. [Phys. Rev. E 62, 6071 (2000)] by means of detailed Monte Carlo simulations in one and two dimensions. Particles of type A may independently ... More
The N/O Plateau of Blue Compact Galaxies: Monte Carlo Simulations of the Observed ScatterMay 10 2006Chemical evolution models and Monte Carlo simulation techniques have been combined for the first time to study the distribution of blue compact galaxies on the N/O plateau. Each simulation comprises 70 individual chemical evolution models. For each model, ... More
Investigating Bar Structure of Disc Galaxies via PRIMAL: A PaRtIcle-by-particle M2M ALgorithmApr 16 2013We have modified our particle-by-particle adaptation of the made-to-measure (M2M) method, with the aim of modelling the Galactic disc from upcoming Galactic stellar survey data. In our new particle-by-particle M2M algorithm, PRIMAL, the observables of ... More
An Assessment of the Energy Budgets of Low-Ionization Nuclear Emission RegionsJan 17 2010Using the SEDs of the weak AGNs 35 LINERs presented in a companion paper, we assess whether photoionization by the weak AGN can power the emission-line luminosities measured through the large (few-arcsecond) apertures used in ground-based spectroscopic ... More
Controlling spin supercurrents via nonequilibrium spin injectionOct 19 2018Jan 26 2019We propose a mechanism whereby spin supercurrents can be manipulated in superconductor/ferromagnet proximity systems via nonequilibrium spin injection. We find that if a spin supercurrent exists in equilibrium, a nonequilibrium spin accumulation will ... More
Restoration of rotational invariance of bound states on the light frontOct 05 1999Mar 18 2000We study bound states in a model with scalar nucleons interacting via an exchanged scalar meson using the Hamiltonian formalism on the light front. In this approach manifest rotational invariance is broken when the Fock space is truncated. By considering ... More
The elapsed time between two transient state observations for an absorbing Markov chainNov 03 2015Consider a system evolving according to an absorbing discrete-time Markov chain with known transition matrix. The state of the system is observed at two points in time, separated by an unknown number of generations. We are interested in calculating the ... More
Experiments in Dilute Atomic Bose-Einstein CondensationMar 05 1999Both theoretical and experimental activity in BEC has expanded dramatically in the three years since the first observation of BEC in a dilute atomic gas. One is tempted to ask, why? Why is there so much interest in the field? Is this burst of activity ... More
On fault-tolerance with noisy and slow measurementsFeb 08 2010Jun 01 2010It is not so well-known that measurement-free quantum error correction protocols can be designed to achieve fault-tolerant quantum computing. Despite the potential advantages of using such protocols in terms of the relaxation of accuracy, speed and addressing ... More
TESS Discovery of an ultra-short-period planet around the nearby M dwarf LHS 3844Sep 19 2018Data from the newly-commissioned \textit{Transiting Exoplanet Survey Satellite} (TESS) has revealed a "hot Earth" around LHS 3844, an M dwarf located 15 pc away. The planet has a radius of $1.32\pm 0.02$ $R_\oplus$ and orbits the star every 11 hours. ... More
Clocked single-spin source based on a spin-split superconductorFeb 29 2016Sep 23 2016We propose an accurate clocked single-spin source for ac-spintronic applications. Our device consists of a superconducting island covered by a ferromagnetic insulator layer through which it is coupled to superconducting leads. Single-particle transfer ... More
Effective lattice theories for Polyakov loopsJun 25 2003Oct 17 2003We derive effective actions for SU(2) Polyakov loops using inverse Monte Carlo techniques. In a first approach, we determine the effective couplings by requiring that the effective ensemble reproduces the single-site distribution of the Polyakov loops. ... More
Effective sigma models and lattice Ward identitiesOct 14 2002We perform a lattice analysis of the Faddeev-Niemi effective action conjectured to describe the low-energy sector of SU(2) Yang-Mills theory. To this end we generate an ensemble of unit vector fields ("color spins") n from the Wilson action. The ensemble ... More
Automorphic products of singular weight for simple latticesFeb 09 2015We classify the simple even lattices of square free level and signature (2,n) for n > 3. A lattice is called simple if the space of cusp forms of weight 1+n/2 for the dual Weil representation of the lattice is trivial. For a simple lattice every formal ... More
Equilibrium finite-frequency noise of an interacting mesoscopic capacitor studied in time-dependent density functional theoryFeb 27 2018We calculate the frequency-dependent equilibrium noise of a mesoscopic capacitor in time-dependent density functional theory (TDDFT). The capacitor is modeled as a single-level quantum dot with on-site Coulomb interaction and tunnel coupling to a nearby ... More
An Eccentric Massive Jupiter Orbiting a Sub-Giant on a 9.5 Day Period Discovered in the Transiting Exoplanet Survey Satellite Full Frame ImagesJan 28 2019We report the discovery of TOI-172 b from the Transiting Exoplanet Survey Satellite (TESS) mission, a massive hot Jupiter transiting a slightly evolved G-star with a 9.48-day orbital period. This is the first planet to be confirmed from analysis of only ... More
An Eccentric Massive Jupiter Orbiting a Sub-Giant on a 9.5 Day Period Discovered in the Transiting Exoplanet Survey Satellite Full Frame ImagesJan 28 2019Mar 18 2019We report the discovery of TOI-172 b from the Transiting Exoplanet Survey Satellite (TESS) mission, a massive hot Jupiter transiting a slightly evolved G-star with a 9.48-day orbital period. This is the first planet to be confirmed from analysis of only ... More
The rotation and Galactic kinematics of mid M dwarfs in the Solar NeighborhoodNov 03 2015Feb 18 2016Rotation is a directly-observable stellar property, and drives magnetic field generation and activity through a magnetic dynamo. Main sequence stars with masses below approximately 0.35Msun (mid-to-late M dwarfs) are fully-convective, and are expected ... More
A Mid-life crisis? Sudden Changes in Radio and X-Ray Emission from Supernova 1970GMar 26 2014Mar 29 2014Supernovae provide a backdrop from which we can probe the end state of stellar evolution in the final years before the progenitor star explodes. As the shock from the supernova expands, the timespan of mass loss history we are able to probe also extends, ... More
Dynamics of the Anderson impurity model: benchmarking a non-adiabatic exchange-correlation potential in time-dependent density functional theorySep 29 2018In this comparative study we benchmark a recently developed non-adiabatic exchange-correlation potential within time-dependent density functional theory (TDDFT) (Phys.\ Rev.\ Lett.\ {\bf 120}, 157701 (2018)) by (a) validating the transient dynamics using ... More
Non-Adiabatic Dynamics in Single-Electron Tunneling Devices with Time-Dependent Density Functional TheoryJun 14 2017Feb 27 2018We simulate the dynamics of a single-electron source, modeled as a quantum dot with on-site Coulomb interaction and tunnel coupling to an adjacent lead, in time-dependent density functional theory. Based on this system, we develop a time-nonlocal exchange-correlation ... More
Near-resonance in a system of sub-Neptunes from TESSJan 25 2019We report the Transiting Exoplanet Survey Satellite ($TESS$) detection of a multi-planet system orbiting the $V=10.9$ K0 dwarf TOI 125. We find evidence for up to five planets, with varying confidence. Three high signal-to-noise transit signals correspond ... More
Techniques for Finding Close-in, Low-mass Planets around SubgiantsNov 05 2018Jupiter-mass planets with large semi-major axes ($a > 1.0$ AU) occur at a higher rate around evolved intermediate mass stars. There is a pronounced paucity of close-in ($a < 0.6$ AU), intermediate period ($5 < P < 100$ days), low-mass ($M_{\rm planet} ... More
Disentangling Time Series Spectra with Gaussian Processes: Applications to Radial Velocity AnalysisFeb 18 2017Measurements of radial velocity variations from the spectroscopic monitoring of stars and their companions are essential for a broad swath of astrophysics, providing access to the fundamental physical properties that dictate all phases of stellar evolution ... More
Analysis of the quantum Zeno effect for quantum control and computationJul 25 2012Mar 26 2013Within quantum information, many methods have been proposed to avoid or correct the deleterious effects of the environment on a system of interest. In this work, expanding on our earlier paper [G. A. Paz-Silva et al., Phys. Rev. Lett. 108, 080501 (2012), ... More
The Occurrence of Non-Pulsating Stars in the gamma Dor and delta Sct Pulsation Instability Regions: Results from Kepler Quarter 14-17 DataJan 31 2015In our 2013 Astronomical Review article, we discussed the statistics of variability for 633 faint spectral type A-F stars observed by the Kepler spacecraft during Quarters 6-13. We found six stars that showed no variability with amplitude 20 ppm or greater ... More
Dialog-based Language LearningApr 20 2016Aug 23 2016A long-term goal of machine learning research is to build an intelligent dialog agent. Most research in natural language understanding has focused on learning from fixed training sets of labeled data, with supervision either at the word level (tagging, ... More