Results for "Johanna K. Teske"

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Magellan/PFS Radial Velocities of GJ 9827, a late K dwarf at 30 pc with Three Transiting Super-EarthsNov 03 2017Feb 28 2018The Kepler mission showed us that planets with sizes between that of Earth and Neptune appear to be the most common type in our Galaxy. These "super-Earths" continue to be of great interest for exoplanet formation, evolution, and composition studies. ... More
The test case of HD26965: difficulties disentangling weak Doppler signals from stellar activityJan 11 2018We report the discovery of a radial velocity signal that can be interpreted as a planetary-mass candidate orbiting the K dwarf HD26965, with an orbital period of 42.364$\pm$0.015 days, or alternatively, as the presence of residual, uncorrected rotational ... More
The Curious Case of Elemental Abundance Differences in the Dual Hot Jupiter Hosts WASP-94ABJan 08 2016Binary stars provide an ideal laboratory for investigating the potential effects of planet formation on stellar composition. Assuming the stars formed in the same environment/from the same material, any compositional anomalies between binary components ... More
APOGEE Data Releases 13 and 14: Stellar Parameter and Abundance Comparisons With Independent AnalysesJul 25 2018Data from the SDSS-IV / Apache Point Observatory Galactic Evolution Experiment (APOGEE-2) have been released as part of SDSS Data Releases 13 (DR13) and 14 (DR14). These include high resolution H-band spectra, radial velocities, and derived stellar parameters ... More
Astro2020 Science White Paper: Toward Finding Earth 2.0: Masses and Orbits of Small Planets with Extreme Radial Velocity PrecisionMar 13 2019Having discovered that Earth-sized planets are common, we are now embarking on a journey to determine if Earth-like planets are also common. Finding Earth-like planets is one of the most compelling endeavors of the 21st century - leading us toward finally ... More
Constraining Stellar Photospheres as an Essential Step for Transmission Spectroscopy of Small ExoplanetsMar 14 2019Transmission spectra probe the atmospheres of transiting exoplanets, but these observations are also subject to signals introduced by magnetic active regions on host stars. Here we outline scientific opportunities in the next decade for providing useful ... More
TOI-150: A transiting hot Jupiter in the TESS southern CVZFeb 26 2019We report the detection of a hot Jupiter ($M_{p}=1.72\pm0.09\ M_{J}$, $R_{p}=1.38\pm0.04\ R_{J}$) orbiting a middle-aged star ($\log g=4.152^{+0.030}_{-0.043}$) in the TESS southern continuous viewing zone ($\beta=-79.59^{\circ}$). We confirm the planetary ... More
A 0.8-2.4 Micron Transmission Spectrum of the Hot Jupiter CoRoT-1bJan 14 2014Hot Jupiters with brightness temperatures > ~2000K can have TiO and VO molecules as gaseous species in their atmospheres. The TiO and VO molecules can potentially induce temperature inversions in hot Jupiter atmospheres and also have an observable signature ... More
Carbon and Oxygen Abundances in Cool Metal-rich Exoplanet Hosts: A Case Study of the C/O Ratio of 55 CancriSep 24 2013The super-Earth exoplanet 55 Cnc e, the smallest member of a five-planet system, has recently been observed to transit its host star. The radius estimates from transit observations, coupled with spectroscopic determinations of mass, provide constraints ... More
A subtle IR excess associated with a young White Dwarf in the Edinburgh-Cape Blue Object SurveyAug 15 2016We report the discovery of a subtle infrared excess associated with the young white dwarf EC\,05365--4749 at 3.35 and 4.6\,$\mu$m. Follow-up spectroscopic observations are consistent with a hydrogen atmosphere white dwarf of effective temperature 22\,800\,K ... More
Optical Observations of the Transiting Exoplanet GJ 1214bFeb 14 2013Feb 22 2013We observed nine primary transits of the super-Earth exoplanet GJ 1214b in several optical photometric bands from March to August 2012, with the goal of constraining the short-wavelength slope of the spectrum of GJ 1214b. Our observations were conducted ... More
Measuring Organic Molecular Emission in Disks with Low Resolution Spitzer SpectroscopyApr 01 2011We explore the extent to which Spitzer IRS spectra taken at low spectral resolution can be used in quantitative studies of organic molecular emission from disks surrounding low mass young stars. We use Spitzer IRS spectra taken in both the high and low ... More
Reduced Activity And Large Particles From the Disintegrating Planet Candidate KIC 12557548bMay 24 2016The intriguing exoplanet candidate KIC 12557548b is believed to have a comet-like tail of dusty debris trailing a small rocky planet. The tail of debris scatters up to 1.3% of the stellar light in the Kepler observatory's bandpass (0.42 um to 0.9 um). ... More
C/O Ratios of Stars with Transiting Hot Jupiter ExoplanetsMar 26 2014The relative abundances of carbon and oxygen have long been recognized as fundamental diagnostics of stellar chemical evolution. Now, the growing number of exoplanet observations enable estimation of these elements in exoplanetary atmospheres. In hot ... More
Abundance Differences Between Exoplanet Binary Host Stars XO-2N and XO-2S -- Dependence on Stellar ParametersJan 09 2015Feb 02 2015The chemical composition of exoplanet host stars is an important factor in understanding the formation and characteristics of their orbiting planets. The best example of this to date is the planet-metallicity correlation. Other proposed correlations are ... More
The Effects of Stellar Companions on Exoplanet Radius DistributionsApr 26 2018Oct 29 2018Understanding the distribution and occurrence rate of small planets was a fundamental goal of the Kepler transiting exoplanet mission, and could be improved with K2 and TESS. Deriving accurate exoplanetary radii requires accurate measurements of the host ... More
Carbon and Oxygen Abundances in the Hot Jupiter Exoplanet Host Star XO-2N and its Binary CompanionApr 01 2013With the aim of connecting the compositions of stars and planets, we present the abundances of carbon and oxygen, as well as iron and nickel, for the transiting exoplanet host star XO-2N and its wide-separation binary companion XO-2S. Stellar parameters ... More
Wave phenomena of the Toda lattice with steplike initial dataOct 13 2015Feb 10 2016We give a survey of the long-time asymptotics for the Toda lattice with steplike constant initial data using the nonlinear steepest descent analysis and its extension based on a suitably chosen $g$-function. Analytic formulas for the leading term of the ... More
Convex equipartitions of colored point setsMay 10 2017Dec 14 2017We show that any $d$-colored set of points in general position in $\mathbb{R}^d$ can be partitioned into $n$ subsets with disjoint convex hulls such that the set of points and all color classes are partitioned as evenly as possible. This extends results ... More
Chemical Abundances of Main-Sequence, Turn-off, Subgiant and red giant Stars from APOGEE spectra I: Signatures of Diffusion in the Open Cluster M67Mar 12 2018Detailed chemical abundance distributions for fourteen elements are derived for eight high-probability stellar members of the solar metallicity old open cluster M67 with an age of $\sim$4 Gyr. The eight stars consist of four pairs, with each pair occupying ... More
Stellar Chemical Clues As To The Rarity of Exoplanetary TectonicsJun 30 2017Jul 03 2017Earth's tectonic processes regulate the formation of continental crust, control its unique deep water and carbon cycles, and are vital to its surface habitability. A major driver of steady-state plate tectonics on Earth is the sinking of the cold subducting ... More
Geometric Modular Action, Wedge Duality and Lorentz Covariance are Equivalent for Generalized Free FieldsOct 20 1999The Tomita-Takesaki modular groups and conjugations for the observable algebras of space-like wedges and the vacuum state are computed for translationally covariant, but possibly not Lorentz covariant, generalized free quantum fields in arbitrary space-time ... More
Geometric Ergodicity of the multivariate COGARCH(1,1) ProcessJan 26 2017Mar 12 2019For the multivariate COGARCH(1,1) volatility process we show sufficient conditions for the existence of a unique stationary distribution, for the geometric ergodicity and for the finiteness of moments of the stationary distribution by a Foster-Lyapunov ... More
An ALMA and MagAO Study of the Substellar Companion GQ Lup BJan 26 2017Multi-wavelength observations provide a complementary view of the formation of young directly-imaged planet-mass companions. We report the ALMA 1.3 mm and Magellan adaptive optics (MagAO) H-alpha, i', z', and Ys observations of the GQ Lup system, a classical ... More
Stellar Companions to the Exoplanet Host Stars HD 2638 and HD 164509Aug 31 2016An important aspect of searching for exoplanets is understanding the binarity of the host stars. It is particularly important because nearly half of the solar-like stars within our own Milky Way are part of binary or multiple systems. Moreover, the presence ... More
A Comparison of Spectroscopic versus Imaging Techniques for Detecting Close Companions to Kepler Objects of InterestAug 26 2015(Abbreviated) Kepler planet candidates require both spectroscopic and imaging follow-up observations to rule out false positives and detect blended stars. [...] In this paper, we examine a sample of 11 Kepler host stars with companions detected by two ... More
XO-2b: a hot Jupiter with a variable host star that potentially affects its measured transit depthMay 05 2015Aug 26 2015The transiting hot Jupiter XO-2b is an ideal target for multi-object photometry and spectroscopy as it has a relatively bright ($V$-mag = 11.25) K0V host star (XO-2N) and a large planet-to-star contrast ratio (R$_{p}$/R$_{s}\approx0.015$). It also has ... More
Detailed Abundances of Stars with Small Planets Discovered by Kepler I: The First SampleNov 03 2015We present newly derived stellar parameters and the detailed abundances of 19 elements of seven stars with small planets discovered by NASA's Kepler Mission. Each star save one has at least one planet with a radius <= 1.6 R_Earth, suggesting a primarily ... More
The Magellan PFS Planet Search Program: Radial Velocity and Stellar Abundance Analyses of the 360 AU, Metal-Poor Binary "Twins" HD 133131A & BAug 22 2016Aug 29 2016We present a new precision radial velocity (RV) dataset that reveals multiple planets orbiting the stars in the $\sim$360 AU, G2$+$G2 "twin" binary HD 133131AB. Our 6 years of high-resolution echelle observations from MIKE and 5 years from PFS on the ... More
Observations of Binary Stars with the Differential Speckle Survey Instrument. V. Toward an Empirical Metal-Poor Mass-Luminosity RelationMar 01 2015In an effort to better understand the details of the stellar structure and evolution of metal poor stars, the Gemini North telescope was used on two occasions to take speckle imaging data of a sample of known spectroscopic binary stars and other nearby ... More
Elicitability of Range Value at RiskFeb 12 2019The predictive performance of point forecasts for a statistical functional, such as the mean, a quantile, or a certain risk measure, is commonly assessed in terms of scoring (or loss) functions. A scoring functions should be (strictly) consistent for ... More
Brown Dwarfs and Directly Imaged Exoplanets in Young AssociationsMar 15 2019In order to understand the atmospheres as well as the formation mechanism of giant planets formed outside our solar system, the next decade will require an investment in studies of isolated young brown dwarfs. In this white paper we summarize the opportunity ... More
The Transiting Exoplanet Community Early Release Science Program for JWSTMar 13 2018Sep 03 2018The James Webb Space Telescope (JWST) presents the opportunity to transform our understanding of planets and the origins of life by revealing the atmospheric compositions, structures, and dynamics of transiting exoplanets in unprecedented detail. However, ... More
Erratum: Higher Order Elicitability and Osband's PrincipleJan 25 2019This note corrects conditions in Proposition 3.4 and Theorem 5.2(ii) and comments on imprecisions in Propositions 4.2 and 4.4 in Fissler and Ziegel (2016).
Doppler Monitoring of the WASP-47 Multiplanet SystemOct 13 2015Oct 28 2015We present precise Doppler observations of WASP-47, a transiting planetary system featuring a hot Jupiter with both inner and outer planetary companions. This system has an unusual architecture and also provides a rare opportunity to measure planet masses ... More
A Six-Planet System Around the Star HD 34445Oct 19 2017We present a new precision radial velocity dataset that reveals a multi-planet system orbiting the G0V star HD 34445. Our 18-year span consists of 333 precision radial velocity observations, 56 of which were previously published, and 277 which are new ... More
Uniform Atmospheric Retrieval Analysis of Ultracool Dwarfs I: Characterizing Benchmarks, Gl570D and HD3651BApr 24 2015May 28 2015Interpreting the spectra of brown dwarfs is key to determining the fundamental physical and chemical processes occurring in their atmospheres. Powerful Bayesian atmospheric retrieval tools have recently been applied to both exoplanet and brown dwarf spectra ... More
Building an Inclusive AAS - The Critical Role of Diversity and Inclusion Training for AAS Council and Astronomy LeadershipOct 05 2016Diversity, equity and inclusion are the science leadership issues of our time. As our nation and the field of astronomy grow more diverse, we find ourselves in a position of enormous potential and opportunity: a multitude of studies show how groups of ... More
An algorithm to detect full irreducibility by bounding the volume of periodic free factorsFeb 28 2014Jul 23 2014We provide an effective algorithm for determining whether an element of the outer automorphism group of a free group is fully irreducible. Our method produces a finite list which can be checked for periodic proper free factors.
Follow-up Imaging of Disk Candidates from the Disk Detective Citizen Science Project: New Discoveries and False-Positives in WISE Circumstellar Disk SurveysSep 25 2018The Disk Detective citizen science project aims to find new stars with excess 22-$\mu$m emission from circumstellar dust in the AllWISE data release from the Wide-field Infrared Survey Explorer (WISE). We evaluated 261 Disk Detective objects of interest ... More
Inverse Scattering Transform for the Toda Hierarchy with Quasi-Periodic BackgroundDec 01 2005We provide a rigorous treatment of the inverse scattering transform for the entire Toda hierarchy in the case of a quasi-periodic finite-gap background solution.
Soliton Solutions of the Toda Hierarchy on Quasi-Periodic Backgrounds RevisitedSep 06 2006Mar 26 2007We investigate soliton solutions of the Toda hierarchy on a quasi-periodic finite-gap background by means of the double commutation method and the inverse scattering transform. In particular, we compute the phase shift caused by a soliton on a quasi-periodic ... More
Distributionally Robust Chance Constrained Optimal Power Flow Assuming Unimodal Distributions with Misspecified ModesSep 19 2018Chance constrained optimal power flow (CC-OPF) formulations have been proposed to minimize operational costs while controlling the risk arising from uncertainties like renewable generation and load consumption. To solve CC-OPF, we often need access to ... More
Geometric Ergodicity of Affine Processes on ConesNov 26 2018For affine processes on finite-dimensional cones, we give criteria for geometric ergodicity - that is exponentially fast convergence to a unique stationary distribution. Ergodic results include both the existence of exponential moments of the limiting ... More
Rarefaction Waves for the Toda Equation via Nonlinear Steepest DescentJan 11 2017Jan 11 2018We apply the method of nonlinear steepest descent to compute the long-time asymptotics of the Toda lattice with steplike initial data corresponding to a rarefaction wave.
Long-Time Asymptotics for the Toda Shock Problem: Non-Overlapping SpectraJun 03 2014Feb 01 2019We derive the long-time asymptotics for the Toda shock problem using the nonlinear steepest descent analysis for oscillatory Riemann--Hilbert factorization problems. We show that the half plane of space/time variables splits into five main regions: The ... More
Bivariate distributions with ordered marginalsFeb 12 2019This paper provides a characterization of all possible dependency structures between two stochastically ordered random variables. The answer is given in terms of all possible copulas that are compatible with the stochastic order. The extremal values for ... More
Hemisphere Partition Function and Analytic Continuation to the Conifold PointFeb 03 2016We show that the hemisphere partition function for certain U(1) gauged linear sigma models (GLSMs) with D-branes is related to a particular set of Mellin-Barnes integrals which can be used for analytic continuation to the singular point in the K\"ahler ... More
The Longest Period TESS Planet Yet: A Sub-Neptune Transiting A Bright, Nearby K Dwarf StarDec 31 2018The future of exoplanet science is bright, as TESS once again demonstrates with the discovery of its longest-period confirmed planet yet, located only 16 pc away. We hereby present HD 21749b (TOI 186.01), a sub-Neptune in a 36-day orbit around a bright ... More
A Hot Saturn Orbiting An Oscillating Late Subgiant Discovered by TESSJan 07 2019We present the discovery of TOI-197.01, the first transiting planet identified by the Transiting Exoplanet Survey Satellite (TESS) for which asteroseismology of the host star is possible. TOI-197 (HIP116158) is a bright (V=8.2 mag), spectroscopically ... More
Back to "Normal" for the Disintegrating Planet Candidate KIC 12557548 bOct 23 2018Nov 11 2018KIC 12557548 b is first of a growing class of intriguing disintegrating planet candidates, which lose mass in the form of a metal rich vapor that condenses into dust particles. Here, we follow up two perplexing observations of the system: 1) the transits ... More
Investigating the physical properties of transiting hot Jupiters with the 1.5-m Kuiper TelescopeAug 26 2017We present new photometric data of 11 hot Jupiter transiting exoplanets (CoRoT-12b, HAT-P-5b, HAT-P-12b, HAT-P-33b, HAT-P-37b, WASP-2b, WASP-24b, WASP-60b, WASP-80b, WASP-103b, XO-3b) in order to update their planetary parameters and to constrain information ... More
Doppler Monitoring of five K2 Transiting Planetary SystemsApr 05 2016May 05 2016In an effort to measure the masses of planets discovered by the NASA {\it K2} mission, we have conducted precise Doppler observations of five stars with transiting planets. We present the results of a joint analysis of these new data and previously published ... More
Observations of Binary Stars with the Differential Speckle Survey Instrument. VIII. Measures of Metal-Poor Stars and Triple Stars from 2015 to 2018Dec 12 2018We present 248 speckle observations of 43 binary and 19 trinary star systems chosen to make progress in two main areas of investigation: the fundamental properties of metal poor stars and star formation mechanisms. The observations were taken at the Gemini ... More
A Machine Learning Approach for Automated Fine-Tuning of Semiconductor Spin QubitsJan 07 2019Mar 08 2019While spin qubits based on gate-defined quantum dots have demonstrated very favorable properties for quantum computing, one remaining hurdle is the need to tune each of them into a good operating regime by adjusting the voltages applied to electrostatic ... More
Semantic Word Clouds with Background Corpus Normalization and t-distributed Stochastic Neighbor EmbeddingAug 11 2017Many word clouds provide no semantics to the word placement, but use a random layout optimized solely for aesthetic purposes. We propose a novel approach to model word significance and word affinity within a document, and in comparison to a large background ... More
Real-Time Energy Disaggregation of a Distribution Feeder's Demand Using Online LearningJan 16 2017May 04 2018Though distribution system operators have been adding more sensors to their networks, they still often lack an accurate real-time picture of the behavior of distributed energy resources such as demand responsive electric loads and residential solar generation. ... More
Exact Maps in Density Functional Theory for Lattice ModelsDec 23 2015In the present work, we employ exact diagonalization for model systems on a real-space lattice to explicitly construct the exact density-to-potential and for the first time the exact density-to-wavefunction map that underly the Hohenberg-Kohn theorem ... More
Bifurcation diagram and stability for a one-parameter family of planar vector fieldsApr 08 2013We consider the 1-parameter family of planar quintic systems, $\dot x= y^3-x^3$, $\dot y= -x+my^5$, introduced by A. Bacciotti in 1985. It is known that it has at most one limit cycle and that it can exist only when the parameter $m$ is in $(0.36,0.6)$. ... More
Cortical Mirror-System Activation During Real-Life Game Playing: An Intracranial Electroencephalography (EEG) StudyFeb 25 2019Analogous to the mirror neuron system repeatedly described in monkeys as a possible substrate for imitation learning and/or action understanding, a neuronal execution/observation matching system (OEMS) is assumed in humans, but little is known to what ... More
New Constraints on Gliese 876 - Exemplar of Mean-Motion ResonanceJan 24 2018Gliese 876 harbors one of the most dynamically rich and well-studied exoplanetary systems. The nearby M4V dwarf hosts four known planets, the outer three of which are trapped in a Laplace mean-motion resonance. A thorough characterization of the complex ... More
Uniform Atmospheric Retrieval Analysis of Ultracool Dwarfs II: Properties of 11 T-dwarfsDec 08 2016Brown dwarf spectra are rich in information revealing of the chemical and physical processes operating in their atmospheres. We apply a recently developed atmospheric retrieval tool to an ensemble of late T-dwarf (600-800K) near infrared spectra. With ... More
The Lick-Carnegie Exoplanet Survey: HD32963 -- A New Jupiter Analog Orbiting a Sun-like StarDec 01 2015We present a set of 109 new, high-precision Keck/HIRES radial velocity (RV) observations for the solar-type star HD 32963. Our dataset reveals a candidate planetary signal with a period of 6.49 $\pm$ 0.07 years and a corresponding minimum mass of 0.7 ... More
Uniform Atmospheric Retrieval Analysis of Ultracool Dwarfs II: Properties of 11 T-dwarfsDec 08 2016Jul 25 2017Brown dwarf spectra are rich in information revealing of the chemical and physical processes operating in their atmospheres. We apply a recently developed atmospheric retrieval tool to an ensemble of late T-dwarf (600-800K) near infrared spectra. With ... More
Assessing the Effect of Stellar Companions from High-Resolution Imaging of Kepler Objects of InterestJan 23 2017We report on 176 close (<2") stellar companions detected with high-resolution imaging near 170 hosts of Kepler Objects of Interest. These Kepler targets were prioritized for imaging follow-up based on the presence of small planets, so most of the KOIs ... More
The LCES HIRES/Keck Precision Radial Velocity Exoplanet SurveyFeb 12 2017We describe a 20-year survey carried out by the Lick-Carnegie Exoplanet Survey Team (LCES), using precision radial velocities from HIRES on the Keck-I telescope to find and characterize extrasolar planetary systems orbiting nearby F, G, K, and M dwarf ... More
Ordering dynamics of snow under isothermal conditionsFeb 28 2010We have investigated the morphological evolution of laboratory new snow under isothermal conditions at different temperatures $T=-3,-9,-19 ^{\circ}C$ by means of X-ray tomography. The collective dynamics of the bicontinuous ice-vapor system is monitored ... More
Seeded growth of monodisperse and spherical silver nanoparticlesJan 29 2014Jun 23 2014Aiming at spherical and monodisperse silver nanoparticles with diameters up to 100 nm, the potential of heterogeneous nucleation of silver particles was explored. Gold seed particles, mainly produced with a spark discharge generator, were carried by nitrogen ... More
Sloan Digital Sky Survey IV: Mapping the Milky Way, Nearby Galaxies, and the Distant UniverseFeb 28 2017Jun 29 2017We describe the Sloan Digital Sky Survey IV (SDSS-IV), a project encompassing three major spectroscopic programs. The Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2) is observing hundreds of thousands of Milky Way stars at high resolution ... More
Elemental Abundances of Kepler Objects of Interest in APOGEE. I. Two Distinct Orbital Period Regimes Inferred from Host Star Iron AbundancesDec 04 2017The Apache Point Observatory Galactic Evolution Experiment (APOGEE) has observed $\sim$600 transiting exoplanets and exoplanet candidates from \textit{Kepler} (Kepler Objects of Interest, KOIs), most with $\geq$18 epochs. The combined multi-epoch spectra ... More
A comprehensive understanding of planet formation is required for assessing planetary habitability and for the search for lifeMar 23 2018Dozens of habitable zone, approximately earth-sized exoplanets are known today. An emerging frontier of exoplanet studies is identifying which of these habitable zone, small planets are actually habitable (have all necessary conditions for life) and, ... More
Dispersion engineering of Quantum Cascade Lasers frequency combsSep 29 2015Quantum cascade lasers are compact sources capable of generating frequency combs. Yet key characteristics - such as optical bandwidth and power-per-mode distribution - have to be improved for better addressing spectroscopy applications. Group delay dispersion ... More
Signatures of Anelastic Domain Relaxation in Ba(Fe$_{1-x}$Co$_{x}$)$_{2}$As$_{2}$ Investigated by Mechanical Modulation of ResistivityMar 12 2019The resistive response of Ba(Fe$_{1-x}$Co$_{x}$)$_{2}$As$_{2}$ to AC mechanical deformation is considered in the multi-domain state. This resistance change depends both upon the anelastic relaxation of domain walls and upon the relation between resistance ... More
The survey of Planetary Nebulae in Andromeda (M31): I. Imaging the disk and halo with MegaCam@CFHTMar 06 2019Mar 08 2019The Andromeda (M31) galaxy subtends nearly 100 sq. deg. on the sky, with severe contamination from the Milky Way halo stars whose surface density displays a steep gradient across the entire M31 field-of-view. Planetary Nebulae (PNe) are a population of ... More
Using GitHub Classroom To Teach StatisticsNov 05 2018Git and GitHub are common tools for keeping track of multiple versions of data analytic content, which allow for more than one person to simultaneously work on a project. GitHub Classroom aims to provide a way for students to work on and submit their ... More
The time-dependent exchange-correlation functional for a Hubbard dimer: quantifying non-adiabatic effectDec 05 2013We address and quantify the role of non-adiabaticity ("memory effects") in the exchange-correlation (xc) functional of time-dependent density functional theory (TDDFT) for describing non-linear dynamics of many-body systems. Time-dependent resonant processes ... More
Personalized Screening Intervals for Biomarkers using Joint Models for Longitudinal and Survival DataMar 22 2015Screening and surveillance are routinely used in medicine for early detection of disease and close monitoring of progression. Biomarkers are one of the primarily tools used for these tasks, but their successful translation to clinical practice is closely ... More
Entanglement Entropy in a Holographic Kondo ModelNov 11 2015Feb 04 2016We calculate entanglement and impurity entropies in a recent holographic model of a magnetic impurity interacting with a strongly coupled system. There is an RG flow to an IR fixed point where the impurity is screened, leading to a decrease in impurity ... More
Human experts vs. machines in taxa recognitionAug 23 2017Jan 11 2019The step of expert taxa recognition currently slows down the response time of many bioassessments. Shifting to quicker and cheaper state-of-the-art machine learning approaches is still met with expert scepticism towards the ability and logic of machines. ... More
A Six-Planet System Orbiting HD 219134Sep 25 2015We present new, high-precision Doppler radial velocity (RV) data sets for the nearby K3V star HD 219134. The data include 175 velocities obtained with the HIRES Spectrograph at the Keck I Telescope, and 101 velocities obtained with the Levy Spectrograph ... More
Exoplanet Science Priorities from the Perspective of Internal and Surface Processes for Silicate and Ice Dominated WorldsApr 13 2018The geophysics of extrasolar planets is a scientific topic often regarded as standing largely beyond the reach of near-term observations. This reality in no way diminishes the central role of geophysical phenomena in shaping planetary outcomes, from formation, ... More
Uncovering functional brain signature via random matrix theoryAug 05 2017Feb 06 2018The brain is organized in a modular way, serving multiple functionalities. This multiplicity requires that both positive (e.g. excitatory, phase-coherent) and negative (e.g. inhibitory, phase-opposing) interactions take place across brain modules. Unfortunately, ... More
Effect of $Z_b$ states on $Υ(3S)\toΥ(1S)ππ$ decaysDec 11 2015Mar 04 2016Within the framework of dispersion theory, we analyze the dipion transitions between the lightest $\Upsilon$ states, $\Upsilon(nS) \rightarrow \Upsilon(mS) \pi\pi$ with $m < n \leq 3$. In particular, we consider the possible effects of two intermediate ... More
Increased dose rate precision in combined $α$ and $β$ counting in the $μ$Dose system - a probabilistic approach to data analysisNov 09 2018The $\mu$Dose system was developed to allow the measurement of environmental levels of natural radioactive isotopes. The system records $\alpha$ and $\beta$ particles along with four decay pairs arising from subsequent decays of $^{214}$Bi/$^{214}$Po, ... More
Ground-based near-UV observations of 15 transiting exoplanets: Constraints on their atmospheres and no evidence for asymmetrical transitsMar 08 2016Transits of exoplanets observed in the near-UV have been used to study the scattering properties of their atmospheres and possible star-planet interactions. We observed the primary transits of 15 exoplanets (CoRoT-1b, GJ436b, HAT-P-1b, HAT-P-13b, HAT-P-16b, ... More
SDSS-V: Pioneering Panoptic SpectroscopyNov 09 2017SDSS-V will be an all-sky, multi-epoch spectroscopic survey of over six million objects. It is designed to decode the history of the Milky Way, trace the emergence of the chemical elements, reveal the inner workings of stars, and investigate the origin ... More
Deformation Theory of Matrix Factorizations and F-Terms in the Boundary Changing SectorJul 30 2009We extend the deformation theory algorithm of matrix factorizations to systems with more than one D-brane. The obstructions to the deformations are F-term equations which can be integrated to an effective superpotential. We demonstrate the power of this ... More
D-Branes in Topological String TheorySep 13 2007This thesis is concerned with D-branes in topological string theory, focusing on the description of B-type D-branes in topological Landau-Ginzburg models. Such D-branes are characterized by matrix factorizations of the Landau-Ginzburg superpotential. ... More
Has the Quark-Gluon Plasma been seen?Oct 27 2005Data from the first three years of running at RHIC are reviewed and put into context with data obtained previously at the AGS and SPS and with the physics question of creation of a quark-gluon plasma in high energy heavy ion collisions. Also some very ... More
New Results of the Konkoly Blazhko GroupOct 18 2009During the recent years the Konkoly Blazhko Group (PIs Johanna Jurcsik and B\'ela Szeidl, co-workers \'Ad\'am S\'odor, Zsombor Hurta and several undergraduate, graduate students) published new important results of Blazhko variables in 15 reviewed Journal ... More
Gravitational Axial Anomaly for Four Dimensional Conformal Field TheoriesMay 24 1999Oct 27 1999We construct the three point function involving an axial vector current and two energy-momentum tensors for four dimensional conformal field theories. Conformal symmetry determines the form of this three point function uniquely up to a constant factor ... More
Postorder rearrangement operatorsOct 10 2014Oct 14 2015We investigate the rearrangement of the Haar system induced by the postorder on the set of dyadic intervals in $[0,1]$ with length greater than or equal to $2^{-N}$. By means of operator norms on $\text{BMO}_N$ we prove that the postorder has maximal ... More
Convolution roots and differentiability of isotropic positive definite functions on spheresJan 27 2012Oct 28 2013We prove that any isotropic positive definite function on the sphere can be written as the spherical self-convolution of an isotropic real-valued function. It is known that isotropic positive definite functions on d-dimensional Euclidean space admit a ... More
Nonparametric estimation for irregularly sampled Lévy processesNov 18 2015Nov 20 2015We consider nonparametric statistical inference for L\'evy processes sampled irregularly, at low frequency. The estimation of the jump dynamics as well as the estimation of the distributional density are investigated. Non-asymptotic risk bounds are derived ... More
The metallicity range of variables in M3Mar 20 2003The recently published spectroscopic metallicities of RR Lyrae stars in M3 (Sandstrom, K., Pilachowski, C. A., and Saha, A. 2001, AJ 122, 3212) though show a relatively wide range of the [Fe/H] values, the conclusion that no metallicity spread is real ... More
A Field-theoretical Interpretation of the Holographic Renormalization GroupMar 26 2001Apr 25 2001A quantum-field theoretical interpretation is given to the holographic RG equation by relating it to a field-theoretical local RG equation which determines how Weyl invariance is broken in a quantized field theory. Using this approach we determine the ... More
Simple, locally finite dimensional Lie algebras in positive characteristicNov 21 2013We prove two structure theorems for simple, locally finite dimensional Lie algebras over an algebraically closed field of characteristic $p$ which give sufficient conditions for the algebras to be of the form $[R^{(-)}, R^{(-)}] / (Z(R) \cap [R^{(-)}, ... More
Convergence to Weighted Fractional Brownian SheetsNov 27 2008We define weighted fractional Brownian sheets, which are a class of Gaussian random fields with four parameters that include fractional Brownian sheets as special cases, and we give some of their properties. We show that for certain values of the parameters ... More
A recipe for short-word pseudo-AnosovsAug 12 2010Given any generating set of any pseudo-Anosov-containing subgroup of the mapping class group of a surface, we construct a pseudo-Anosov with word length bounded by a constant depending only on the surface. More generally, in any subgroup G we find an ... More
Uniform uniform exponential growth of subgroups of the mapping class groupMay 01 2008Oct 04 2009Let Mod(S) denote the mapping class group of a compact, orientable surface S. We prove that finitely generated subgroups of Mod(S) which are not virtually abelian have uniform exponential growth with minimal growth rate bounded below by a constant depending ... More