Astronomy and Astrophysics – Astrophysics – Earth and Planetary Astrophysics
Scientific paper
2011-03-13
Astronomy and Astrophysics
Astrophysics
Earth and Planetary Astrophysics
Submitted to ApJ, 22 pages, 10 figures
Scientific paper
We report the distribution of planets as a function of planet radius (R_p), orbital period (P), and stellar effective temperature (Teff) for P < 50 day orbits around GK stars. These results are based on the 1,235 planets (formally "planet candidates") from the Kepler mission that include a nearly complete set of detected planets as small as 2 Earth radii (Re). For each of the 156,000 target stars we assess the detectability of planets as a function of R_p and P. We also correct for the geometric probability of transit, R*/a. We consider first stars within the "solar subset" having Teff = 4100-6100 K, logg = 4.0-4.9, and Kepler magnitude Kp < 15 mag. We include only those stars having noise low enough to permit detection of planets down to 2 Re. We count planets in small domains of R_p and P and divide by the included target stars to calculate planet occurrence in each domain. Occurrence of planets varies by more than three orders of magnitude and increases substantially down to the smallest radius (2 Re) and out to the longest orbital period (50 days, ~0.25 AU) in our study. For P < 50 days, the radius distribution is given by a power law, df/dlogR= k R^\alpha. This rapid increase in planet occurrence with decreasing planet size agrees with core-accretion, but disagrees with population synthesis models. We fit occurrence as a function of P to a power law model with an exponential cutoff below a critical period P_0. For smaller planets, P_0 has larger values, suggesting that the "parking distance" for migrating planets moves outward with decreasing planet size. We also measured planet occurrence over Teff = 3600-7100 K, spanning M0 to F2 dwarfs. The occurrence of 2-4 Re planets in the Kepler field increases with decreasing Teff, making these small planets seven times more abundant around cool stars than the hottest stars in our sample. [abridged]
Basri Gibor S.
Batalha Natalie M.
Borucki William. J.
Boss Alan
Brown Timothy M.
No associations
LandOfFree
Planet Occurrence within 0.25 AU of Solar-type Stars from Kepler does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Planet Occurrence within 0.25 AU of Solar-type Stars from Kepler, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Planet Occurrence within 0.25 AU of Solar-type Stars from Kepler will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-233965