Search Publications

APOGEE Data and Spectral Analysis from SDSS Data Release 16: Seven Years of Observations Including First Results from APOGEE-South
DOI: 10.3847/1538-3881/aba592 Bibcode: 2020AJ....160..120J

Bizyaev, Dmitry; Bovy, Jo; Cunha, Katia +20 more

The spectral analysis and data products in Data Release 16 (DR16; 2019 December) from the high-resolution near-infrared Apache Point Observatory Galactic Evolution Experiment (APOGEE)-2/Sloan Digital Sky Survey (SDSS)-IV survey are described. Compared to the previous APOGEE data release (DR14; 2017 July), APOGEE DR16 includes about 200,000 new ste…

2020 The Astronomical Journal
Gaia 404
The Gaia-Kepler Stellar Properties Catalog. I. Homogeneous Fundamental Properties for 186,301 Kepler Stars
DOI: 10.3847/1538-3881/159/6/280 Bibcode: 2020AJ....159..280B

van Saders, Jennifer L.; Huber, Daniel; Berger, Travis A. +3 more

An accurate and precise Kepler Stellar Properties Catalog is essential for the interpretation of the Kepler exoplanet survey results. Previous Kepler Stellar Properties Catalogs have focused on reporting the best-available parameters for each star, but this has required combining data from a variety of heterogeneous sources. We present the Gaia-Ke…

2020 The Astronomical Journal
Gaia 232
SOAR TESS Survey. I. Sculpting of TESS Planetary Systems by Stellar Companions
DOI: 10.3847/1538-3881/ab55e9 Bibcode: 2020AJ....159...19Z

Ziegler, Carl; Tokovinin, Andrei; Mann, Andrew W. +3 more

The Transiting Exoplanet Survey Satellite (TESS) is finding transiting planet candidates around bright, nearby stars across the entire sky. The large field of view, however, results in low spatial resolution; therefore, multiple stars contribute to almost every TESS light curve. High angular resolution imaging can detect the previously unknown com…

2020 The Astronomical Journal
Gaia 195
The Gaia-Kepler Stellar Properties Catalog. II. Planet Radius Demographics as a Function of Stellar Mass and Age
DOI: 10.3847/1538-3881/aba18a Bibcode: 2020AJ....160..108B

van Saders, Jennifer L.; Huber, Daniel; Berger, Travis A. +2 more

Studies of exoplanet demographics require large samples and precise constraints on exoplanet host stars. Using the homogeneous Kepler stellar properties derived using the Gaia Data Release 2 by Berger et al., we recompute Kepler planet radii and incident fluxes and investigate their distributions with stellar mass and age. We measure the stellar m…

2020 The Astronomical Journal
Gaia 171
The Sixth Data Release of the Radial Velocity Experiment (RAVE). II. Stellar Atmospheric Parameters, Chemical Abundances, and Distances
DOI: 10.3847/1538-3881/ab9ab8 Bibcode: 2020AJ....160...83S

Grebel, Eva K.; Chaplin, William J.; Steinmetz, Matthias +60 more

We present part 2 of the sixth and final Data Release (DR6) of the Radial Velocity Experiment (RAVE), a magnitude-limited ( $9\lt I\lt 12$ ) spectroscopic survey of Galactic stars randomly selected in Earth's southern hemisphere. The RAVE medium-resolution spectra (R ∼ 7500) cover the Ca triplet region (8410-8795 Å) and span the complete time fram…

2020 The Astronomical Journal
Gaia 138
Evolution of the Radius Valley around Low-mass Stars from Kepler and K2
DOI: 10.3847/1538-3881/ab8237 Bibcode: 2020AJ....159..211C

Cloutier, Ryan; Menou, Kristen

We present calculations of the occurrence rate of small close-in planets around low-mass dwarf stars using the known planet populations from the Kepler and K2 missions. Applying completeness corrections clearly reveals the radius valley in the maximum a posteriori occurrence rates as a function of orbital separation and planet radius. We measure t…

2020 The Astronomical Journal
Gaia 137
Population-level Eccentricity Distributions of Imaged Exoplanets and Brown Dwarf Companions: Dynamical Evidence for Distinct Formation Channels
DOI: 10.3847/1538-3881/ab5b11 Bibcode: 2020AJ....159...63B

Nielsen, Eric L.; Blunt, Sarah C.; Bowler, Brendan P.

The orbital eccentricities of directly imaged exoplanets and brown dwarf companions provide clues about their formation and dynamical histories. We combine new high-contrast imaging observations of substellar companions obtained primarily with Keck/NIRC2 together with astrometry from the literature to test for differences in the population-level e…

2020 The Astronomical Journal
Gaia 136
The Sixth Data Release of the Radial Velocity Experiment (RAVE). I. Survey Description, Spectra, and Radial Velocities
DOI: 10.3847/1538-3881/ab9ab9 Bibcode: 2020AJ....160...82S

Grebel, Eva K.; Chaplin, William J.; Steinmetz, Matthias +60 more

The Radial Velocity Experiment (RAVE) is a magnitude-limited (9 < I < 12) spectroscopic survey of Galactic stars randomly selected in Earth's southern hemisphere. The RAVE medium-resolution spectra (R ∼ 7500) cover the Ca-triplet region (8410-8795 Å). The sixth and final data release (DR6) is based on 518,387 observations of 451,783 unique s…

2020 The Astronomical Journal
Gaia 133
The Open Cluster Chemical Abundances and Mapping Survey. IV. Abundances for 128 Open Clusters Using SDSS/APOGEE DR16
DOI: 10.3847/1538-3881/ab77bc Bibcode: 2020AJ....159..199D

Bizyaev, Dmitry; Brownstein, Joel R.; Pan, Kaike +22 more

The Open Cluster Chemical Abundances and Mapping (OCCAM) survey aims to constrain key Galactic dynamical and chemical evolution parameters by the construction of a large, comprehensive, uniform, infrared-based spectroscopic data set of hundreds of open clusters. This fourth contribution from the OCCAM survey presents analysis using Sloan Digital S…

2020 The Astronomical Journal
Gaia 120
Flare Statistics for Young Stars from a Convolutional Neural Network Analysis of TESS Data
DOI: 10.3847/1538-3881/abac0a Bibcode: 2020AJ....160..219F

Schlieder, Joshua E.; Günther, Maximilian N.; Montet, Benjamin T. +5 more

All-sky photometric time-series missions have allowed for the monitoring of thousands of young (tage < 800 Myr) stars in order to understand the evolution of stellar activity. Here, we developed a convolutional neural network (CNN), stella, specifically trained to find flares in Transiting Exoplanet Survey Satellite (TESS) short-cade…

2020 The Astronomical Journal
Gaia 109