From Pebbles to Planets----中国科学院紫金山天文台

Seminar Title	From Pebbles to Planets

Speaker:	Dr. LIU Beibei

Affiliation:	(Lund university, Sweden)

When	Friday morning, Sept. 27, 10:00 a.m.

Where:	Room 212, Astronomy Building
	Welcome to Attend

	( PMO Academic Committee & Academic Circulating committee)

Abstract: I will briefly introduce four major stages of planet formation. Dust grains first coagulate by perfect sticking but cannot further grow beyond meter size. Streaming instability is a key mechanism that clusters pebbles (~mm-cm size particles) into planetesimals with the help of self-gravity. After planetesimals form, they can grow into protoplanets by feeding from other planetesimals as well as by accreting inwardly drifting pebbles from the outer disk. The transition from planetesimal-dominated accretion to pebble-dominated accretion is around 1e-2 Earth mass. The subsequent planet growth is driven by pebble accretion and their core mass is regulated by the pebble isolation mass.

I will follow-up present a pebble-driven core accretion model to study the formation of planets around stars in the stellar mass range of 0.08 solar mass to 1 solar mass. The forming planet population is compared with the observed exoplanets in terms of mass, metallicity and water content. The results succeed in quantitatively reproducing several observed properties of exoplanets and correlations with their stellar hosts.