Search Publications
Overview of the DESI Legacy Imaging Surveys
Castander, Francisco J.; Gaztanaga, Enrique; Bell, Eric F. +158 more
The DESI Legacy Imaging Surveys (http://legacysurvey.org/) are a combination of three public projects (the Dark Energy Camera Legacy Survey, the Beijing-Arizona Sky Survey, and the Mayall z-band Legacy Survey) that will jointly image ≈14,000 deg2 of the extragalactic sky visible from the northern h…
The Revised TESS Input Catalog and Candidate Target List
Torres, Guillermo; Barclay, Thomas; Ge, Jian +34 more
We describe the catalogs assembled and the algorithms used to populate the revised TESS Input Catalog (TIC), based on the incorporation of the Gaia second data release. We also describe a revised ranking system for prioritizing stars for 2 minute cadence observations, and we assemble a revised Candidate Target List (CTL) using that ranking. The TI…
The Gemini Planet Imager Exoplanet Survey: Giant Planet and Brown Dwarf Demographics from 10 to 100 au
Burrows, Adam; Fortney, Jonathan J.; Duchêne, Gaspard +63 more
We present a statistical analysis of the first 300 stars observed by the Gemini Planet Imager Exoplanet Survey. This subsample includes six detected planets and three brown dwarfs; from these detections and our contrast curves we infer the underlying distributions of substellar companions with respect to their mass, semimajor axis, and host stella…
Untangling the Galaxy. I. Local Structure and Star Formation History of the Milky Way
Kounkel, Marina; Covey, Kevin
Gaia DR2 provides unprecedented precision in measurements of the distance and kinematics of stars in the solar neighborhood. Through applying unsupervised machine learning on DR2's 5D data set (3D position + 2D velocity), we identify a number of clusters, associations, and comoving groups within 1 kpc and | b| < 30^\circ (many of which have not…
Occurrence Rates of Planets Orbiting FGK Stars: Combining Kepler DR25, Gaia DR2, and Bayesian Inference
Ford, Eric B.; Ragozzine, Darin; Hsu, Danley C. +1 more
We characterize the occurrence rate of planets, ranging in size from 0.5 to 16 R ⊕, orbiting FGK stars with orbital periods from 0.5 to 500 days. Our analysis is based on results from the “DR25” catalog of planet candidates produced by NASA’s Kepler mission and stellar radii from Gaia “DR2.” We incorporate additional Kepler data product…
The Solar Neighborhood. XLV. The Stellar Multiplicity Rate of M Dwarfs Within 25 pc
Henry, Todd J.; Winters, Jennifer G.; Jao, Wei-Chun +6 more
We present results of the largest, most comprehensive study ever done of the stellar multiplicity of the most common stars in the Galaxy, the red dwarfs. We have conducted an all-sky volume-limited survey for stellar companions to 1120 M dwarf primaries known to lie within 25 pc of the Sun via trigonometric parallaxes. In addition to a comprehensi…
The Hubble Space Telescope PanCET Program: Exospheric Mg II and Fe II in the Near-ultraviolet Transmission Spectrum of WASP-121b Using Jitter Decorrelation
Nikolov, Nikolay; Mikal-Evans, Thomas; Sing, David K. +18 more
We present Hubble Space Telescope (HST) near-ultraviolet (NUV) transits of the hot Jupiter WASP-121b, acquired as part of the PanCET program. Time-series spectra during two transit events were used to measure the transmission spectra between 2280 and 3070 Å at a resolution of 30,000. Using HST data from 61 Space Telescope Imaging Spectrograph visi…
Kepler Planet Occurrence Rates for Mid-type M Dwarfs as a Function of Spectral Type
Muirhead, Philip S.; Cushing, Michael C.; Christiansen, Jessie L. +1 more
Previous studies of planet occurrence rates largely relied on photometric stellar characterizations. In this paper, we present planet occurrence rates for mid-type M dwarfs using spectroscopy, parallaxes, and photometry to determine stellar characteristics. Our spectroscopic observations have allowed us to constrain spectral type, temperatures, an…
An Excess of Jupiter Analogs in Super-Earth Systems
Lee, Eve J.; Knutson, Heather A.; Batygin, Konstantin +4 more
We use radial velocity (RV) observations to search for long-period gas giant companions in systems hosting inner super-Earth (1-4 R ⊕, 1-10 M ⊕) planets to constrain formation and migration scenarios for this population. We consistently refit published RV data sets for 65 stars and find nine systems with statistically signifi…
Precise Dynamical Masses of Directly Imaged Companions from Relative Astrometry, Radial Velocities, and Hipparcos-Gaia DR2 Accelerations
Dupuy, Trent J.; Bowler, Brendan P.; Brandt, Timothy D.
We measure dynamical masses for five objects—three ultracool dwarfs, one low-mass star, and one white dwarf—by fitting orbits to a combination of the Hipparcos-Gaia Catalog of Accelerations, literature radial velocities, and relative astrometry. Our approach provides precise masses without any assumptions about the primary star, even though the ob…