3:30–5:00 pm ERC 161
Title: Formation and Evolution of Close-In Small Exoplanets: Linking Theory to Observed Trends
Abstract: Super-Earths and mini-Neptunes are the most common type of planet in our galaxy, yet their origins and evolutionary histories remain puzzling. In this talk, I will explore how recent theoretical advances in planet formation --particularly the idea that planets form from narrow rings of planetesimals and the subsequent "breaking the chain'' model of orbital evolution --offer a unifying framework to explain observations. In this picture, planets assemble in rings at a range of orbital distances and migrate inward, becoming locked into resonant chains at the disk’s inner edge. These chains are fragile: after the gas disperses, instabilities and giant impacts often shatter the resonances, sculpting the planetary architectures we observe today. This evolutionary pathway naturally reproduces key observed trends such as the period ratio distribution, intra-system radius uniformity, and the bimodal radius distribution. I will also present results suggesting unexpectedly large eccentricities among planets inside the radius valley, and examine possible dynamical pathways that could produce them. Taken together, these findings suggest that while a handful of systems retain their pristine resonant architecture, the majority of close-in planetary systems are survivors of a violent dynamical adolescence.
Zoom: https://uchicago.zoom.us/j/95163709101?pwd=n2tRNMeI5Cda1rL9rVCXL7eApjQJSl.1
