2018/01/11 by Li Zeng, S. B. Jacobsen, Zeng, Li +5
Physics and Astronomy · #Astronomy and Astrophysical Research #Astrophysics and Star Formation Studies #Earth and Planetary Astrophysics (astro-ph.EP) #FOS: Physical sciences #Stellar, planetary, and galactic studies
paper · pdf · doi:10.48550/arxiv.1801.03994
openalex publication_date 2018/01/11 · openalex created_date 2018/01/26 · openalex updated_date 2026/07/28
Applying survival function analysis to the planet orbital period (P) and semi-major axis (a) distribution from the Kepler sample, we find that all exoplanets are uniformly distributed in (ln a) or (ln P), with an average inner cut-off of 0.05 AU to the host star. More specifically, this inner cut-off is 0.04 AU for rocky worlds (1-2 Earth radii) and 0.08 AU for water worlds (2-4 Earth radii). Moreover, the transitional planets (4-10 Earth radii) and gas giants (>10 Earth radii) have a change of slope of survival function at 0.4 AU from -1 to -1/2, suggesting a different statistical distribution uniform in \Sqrt[a] inside 0.4 AU, compared to small exoplanets (<4 Earth radii). This difference in distribution is likely caused by the difference in planet migration mechanism, and susceptibility to host stellar irradiation, for gas-poor (<4 Earth radii) versus gas-rich (>4 Earth radii) planets. Armed with this knowledge and combined with the survival function analysis of planet size distribution, we can make precise estimates of planet occurrence rate and predict the TESS mission yield.