A Tale of Planet Formation: from dust to planets

主讲人 (Speaker): 刘尚飞

主讲人单位 (Speaker's Institute): Rice University

邀请人 (Invited by): 余聪

时间 (Time): 星期三, 2018/06/13 - 15:00 to 16:00

地点 (Location): 珠海校区海滨红楼17栋107会议室

摘要 (Abstract):

Planet formation can be divided into two stages. In the protoplanetary disk stage, micrometer-sized dust grains coagulate and continue to grow into kilometer-sized planetesimals, followed by planetary embryo formation and run-away gas accretion. After the gaseous disk dispersal in a few million years, hundreds of protoplanets can be formed and they gravitationally interact with each other under the influence of a few giant planets, which leads to many chaotic events such as collisions and ejections. This picture of planet formation is still highly simplified as the whole process is not well understood from both theory (simulations) and observations in many aspects. Because of a 12-order-of-magnitude variation in size from dust grains to planets as well as complex physics at all scales, direct numerical simulations are prohibited and different approaches were developed for studying certain stages of planet formation. From observational point of view, only a tiny portion of the size spectrum is probed by observations. Until recently sub-millimeter-sized dust grains in protoplanetary disks can be well constrained by radial interferometers such as ALMA. On the other hand, matured planetary systems have been discovered by direct and indirect methods (most notably by transit satellite Kepler). In this talk, I will briefly review the current picture of planet formation and recent progress. In particular, I will focus on protoplanetary disks and diversity of exoplanets, which can be tested from both the theory and observations.

主讲人简介 (Speaker's CV):

2015-Present:Postdoctoral researcher, Department of Physics and Astronomy, Rice University, USA 2015 - 2016:Visiting postdoctoral researcher, Los Alamos National Laboratory, USA 2013 - 2015:Postdoctoral researcher, Department of Earth and Planetary Sciences, UCSC, USA Apr. - Aug. 2010, Jan. - Jun. 2012:Visiting Student / Junior Specialist;Department of Astronomy and Astrophysics, UCSC, USA 2008 - 2013:PhD candidate, Department of Astronomy, Peking University, China.