Evidence of Different Formation Mechanisms for Hot versus Warm Super-Earths

Wei Zhu (OSU)
(Submitted on 5 Mar 2015)
Using the Kepler planet sample from Buchhave et al. and the statistical method clarified by Schlaufman, I show that the shorter-period super-Earths have a different dependence on the host star metallicity from the longer-period super-Earths, with the transition period being in the period range from 70 to 100 days. The hosts of shorter-period super-Earths are on average more metal-rich than those of longer-period super-Earths. The existence of such a transition period cannot be explained by any single theory of super-Earth formation, suggesting that super-Earths have formed via at least two mechanisms.
Comments: 11 pages, 5 figures; submitted to ApJ Letters
Subjects: Earth and Planetary Astrophysics (astro-ph.EP)
Cite as: arXiv:1503.01771 [astro-ph.EP] (or arXiv:1503.01771v1 [astro-ph.EP] for this version)
Submission history
From: Wei Zhu
[v1] Thu, 5 Mar 2015 21:00:07 GMT (105kb)