2010/05/24 by John Asher Johnson, Kimberly M. Aller, Andrew W. Howard +1 · 1 citation
Physics and Astronomy · #Astronomy and Astrophysical Research #Giant planet #Giant star #Metallicity #Planet #Planetary mass #Planetary system #Scientific Research and Discoveries #Stars #Stellar evolution #Stellar mass #Stellar mass loss #Stellar, planetary, and galactic studies #astro-ph.EP #astro-ph.SR
paper · pdf · doi:10.1086/655775
Fixed minor typos, modified the last paragraph of Section 6
arxiv created 2010/05/24 · openalex publication_date 2010/07/22 · arxiv updated 2015/05/19 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Correlations between stellar properties and the occurrence rate of exoplanets can be used to inform the target selection of future planet-search efforts and provide valuable clues about the planet-formation process. We analyze a sample of 1266 stars drawn from the California Planet Survey targets to determine the empirical functional form describing the likelihood of a star harboring a giant planet as a function of its mass and metallicity. Our stellar sample ranges from M dwarfs with masses as low as 0.2 M ⊙ to intermediate-mass subgiants with masses as high as 1.9 M ⊙ . In agreement with previous studies, our sample exhibits a planet-metallicity correlation at all stellar masses; the fraction of stars that harbor giant planets scales as f ∝ 10 1.2[Fe/H] . We can rule out a flat metallicity relationship among our evolved stars (at 98% confidence), which argues that the high metallicities of stars with planets is not likely due to convective envelope "pollution." Our data also rule out a constant planet occurrence rate for [Fe/H] < 0, indicating that giant planets continue to become rarer at sub-Solar metallicities. We also find that planet occurrence increases with stellar mass ( f ∝ M ⋆ ), characterized by a rise from 3% around M dwarfs (0.5 M ⊙ ) to 14% around A stars (2 M ⊙ ), at Solar metallicity. We argue that the correlation between stellar properties and giant planet occurrence is strong supporting evidence of the core-accretion model of planet formation.