Abstract

The relative importance of pebble versus planetesimal accretion presents the most important uncertainty in current planet formation models. Since pebble accretion has much lower efficiency than planetesimal accretion, we expect that planets formed in circumstellar disks with little planetmaking materials available cannot be formed via pebble accretion. We conducted a large suite of computational planet formation experiments to test this hypothesis by examining the impact of varying pebble accretion efficiency on the structure of fully-grown planetary systems. We compared our simulated systems to observed exoplanet systems to identify a subset of systems that could not have been formed by pebble accretion alone. Our results will be a crucial step forward towards demystifying the formation history of the diverse population of exoplanets observed.

CHRIS LE WANG is
a third-year computer
science and physics
major.