The Gemini Planet Imager Exoplanet Survey: Giant Planet and Brown Dwarf Demographics from 10 To 100 Au

Authors

• Eric L. Nielsen, Kavli Institute for Particle Astrophysics and Cosmology
• Robert J. De Rosa, Kavli Institute for Particle Astrophysics and Cosmology
• Bruce Macintosh, Kavli Institute for Particle Astrophysics and Cosmology
• Jason J. Wang, California Institute of Technology
• Jean Baptiste Ruffio, Kavli Institute for Particle Astrophysics and Cosmology
• Eugene Chiang, University of California, Berkeley
• Mark S. Marley, NASA Ames Research Center
• Didier Saumon, Los Alamos National Laboratory
• Dmitry Savransky, Cornell University College of Engineering
• S. Mark Ammons, Lawrence Livermore National Laboratory
• Vanessa P. Bailey, Jet Propulsion Laboratory
• Travis Barman, The University of Arizona
• Célia Blain, National Research Council Canada
• Joanna Bulger, National Institutes of Natural Sciences - National Astronomical Observatory of Japan
• Adam Burrows, Princeton University
• Jeffrey Chilcote, Kavli Institute for Particle Astrophysics and Cosmology
• Tara Cotten, University of Georgia
• Ian Czekala, Kavli Institute for Particle Astrophysics and Cosmology
• Rene Doyon, Institut de Recherche sur les Exoplanètes
• Gaspard Duchene, University of California, Berkeley
• Thomas M. Esposito, University of California, Berkeley
• Daniel Fabrycky, The University of Chicago
• Michael P. Fitzgerald, University of California, Los Angeles
• Katherine B. Follette, Amherst College
• Jonathan J. Fortney, University of California, Santa Cruz
• Benjamin L. Gerard, National Research Council Canada
• Stephen J. Goodsell, Gemini Observatory
• James R. Graham, University of California, Berkeley
• Alexandra Z. Greenbaum, University of Michigan, Ann Arbor
• Pascale Hibon, European Southern Observatory Santiago
• Sasha Hinkley, University of Exeter
• Lea A. Hirsch, Kavli Institute for Particle Astrophysics and Cosmology
• Kimberly Ward-Duong, Arizona State UniversityFollow
• et al, Various Institutions

Document Type

Article

Publication Date

1-1-2019

Publication Title

Astronomical Journal

Abstract

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 stellar mass. We uncover a strong correlation between planet occurrence rate and host star mass, with stars M ∗ >1.5 M o more likely to host planets with masses between 2 and 13M Jup and semimajor axes of 3-100 au at 99.92% confidence. We fit a double power-law model in planet mass (m) and semimajor axis (a) for planet populations around high-mass stars (M ∗ >1.5 M o) of the form , finding α = -2.4 +0.8 and β = -2.0 +0.5, and an integrated occurrence rate of % between 5-13M Jup and 10-100 au. A significantly lower occurrence rate is obtained for brown dwarfs around all stars, with % of stars hosting a brown dwarf companion between 13-80M Jup and 10-100 au. Brown dwarfs also appear to be distributed differently in mass and semimajor axis compared to giant planets; whereas giant planets follow a bottom-heavy mass distribution and favor smaller semimajor axes, brown dwarfs exhibit just the opposite behaviors. Comparing to studies of short-period giant planets from the radial velocity method, our results are consistent with a peak in occurrence of giant planets between ∼1 and 10 au. We discuss how these trends, including the preference of giant planets for high-mass host stars, point to formation of giant planets by core/pebble accretion, and formation of brown dwarfs by gravitational instability.

Keywords

instrumentation: adaptive optics, planetary systems, planets and satellites: detection

Volume

158

Issue

1

DOI

https://doi.org/10.3847/1538-3881/ab16e9

ISSN

00046256

Rights

© 2019. The American Astronomical Society.

Version

Version of Record

Recommended Citation

Nielsen, Eric L.; De Rosa, Robert J.; Macintosh, Bruce; Wang, Jason J.; Ruffio, Jean Baptiste; Chiang, Eugene; Marley, Mark S.; Saumon, Didier; Savransky, Dmitry; Mark Ammons, S.; Bailey, Vanessa P.; Barman, Travis; Blain, Célia; Bulger, Joanna; Burrows, Adam; Chilcote, Jeffrey; Cotten, Tara; Czekala, Ian; Doyon, Rene; Duchene, Gaspard; Esposito, Thomas M.; Fabrycky, Daniel; Fitzgerald, Michael P.; Follette, Katherine B.; Fortney, Jonathan J.; Gerard, Benjamin L.; Goodsell, Stephen J.; Graham, James R.; Greenbaum, Alexandra Z.; Hibon, Pascale; Hinkley, Sasha; Hirsch, Lea A.; Ward-Duong, Kimberly; and al, et, "The Gemini Planet Imager Exoplanet Survey: Giant Planet and Brown Dwarf Demographics from 10 To 100 Au" (2019). Astronomy: Faculty Publications, Smith College, Northampton, MA.
https://scholarworks.smith.edu/ast_facpubs/120