Work

Emerging Trends in a Period-radius Distribution of Close-in Planets

Year: 2012
Type: article
Abstract: We analyze the distribution of extrasolar planets (both confirmed and Kepler candidates) according to their orbital periods P and planetary radii R . Among confirmed planets, we find compelling evidence for a paucity of bodies with 3 R ⊕ < R < 10 R ⊕ , where R ⊕ is Earth's radius and P < 2–3 days. We have christened this region a sub-Jovian Pampas . The same trend is detected in multiplanet Kepler candidates. Although approximately 16 Kepler single-planet candidates inhabit this Pampas, at least 7 are probable false positives (FPs). This last number could be significantly higher if the ratio of FPs is higher than 10%, as suggested by recent studies. In a second part of the paper we analyze the distribution of planets in the ( P , R ) plane according to stellar metallicities. We find two interesting trends: (1) a lack of small planets ( R < 4 R ⊕ ) with orbital periods P < 5 days in metal-poor stars and (2) a paucity of sub-Jovian planets (4 R ⊕ < R < 8 R ⊕ ) with P < 100 days, also around metal-poor stars. Although all these trends are preliminary, they appear statistically significant and deserve further scrutiny. If confirmed, they could represent important constraints on theories of planetary formation and dynamical evolution.
Authors: C. Beaugé, D. Nesvorný
Language: English
Open Access status: bronze
OpenAlex ID: W1985371196
FWCI: 3.058
Cites: 45
Cited by: 217
Related to: 10