The occurrence rates of young, Neptune-sized planets with ages less than 200 Myr

In this talk, we will present our occurrence rates of short-period, young planets (< 200 Myr). We conducted a holistic occurrence rate study using both Full Frame Images (FFIs) and the 2 minute cadence observations from NASA’s Transiting Exoplanet Survey Satellite (TESS). We sampled over 8000 total stars known to reside in young clusters or associations, and recovered 19 planets and candidates, including 5 newly identified candidates. We find evidence for both period and radius evolution of planets over the first hundred million years. We find a distinct increase in the occurrence of both Neptune sized planets, and planets residing in ~10 day orbital periods when compared to the mature age population. Our occurrence rates test the contraction, photoevaporation, and potentially migration processes that all planets undergo early in their lives. This is the critical timescale by which the intense XUV irradiation from young, active host stars is thought to strip planets’ primordial atmospheres. Comparing the population of planets around young stars against that of their mature counterparts is one avenue to time stamp these processes as they occur.