Special PLS – Anne Dattilo (UCSC)

Title: Mapping Kepler Occurrence to the Physics of Planet Evolution

Abstract: The Kepler mission enabled us to look at the intrinsic population of exoplanets within our galaxy. The occurrence of planets in the period-radius diagram is rife with structure that can be used to constrain planet formation and evolution theory. We compute Kepler occurrence with a KDE methodology and measure the radius and period distribution of planets from 0.5-16Re and 1-400 days. We then use these occurrence measurements to tie-in evolution theory of the radius valley and of the radius cliff, a steep drop-off in occurrence at 3 Re that separates the sub-Neptune population from the rarer Neptunes. We characterize the slope of the cliff as a function of orbital period as well as insolation flux and find the cliff shape is not constant. It becomes flatter with increasing orbital period (and decreasing insolation flux), implying the radius distribution of sub-Neptune and Neptune-sized planets is related to their formation location. Finally, we use population synthesis models that replicate the slope of the radius valley to compare with the occurrence distribution in order to constrain formation and evolution pathways.

About this Series: The Atmospheres, Ocean and Climate Sack Lunch Seminar Series is an informal seminar series within PAOC that focuses on more specialized topics than the PAOC Colloquium. Seminar topics include all research concerning the science of atmospheres, ocean and climate. The seminars usually take place on Wednesdays from 12-1pm. The presentations are either given by an invited speaker or by a member of PAOC and can focus on new research or discussion of a paper of particular interest. Contact: sacklunch-committee@mit.edu for more information and Zoom password