报告题目:A rocky road from dust to planets

报  告  人:Prof. Min-Kai Lin (ASIAA , Taiwan)

报告时间:Thursday, May 30, 2019, 02:00pm

报告地点:蒙民伟科技南楼S727

报告摘要:Planets appears commonplace in the Universe. However, the details of their formation remains a puzzle. The building blocks of planets are planetesimals, themselves formed from small dust grains immersed in a gaseous protoplanetary disk (PPD) surrounding young stars. Thus, understanding the dust-gas dynamics in PPDs lays the foundation to any theory of planet formation. I will present recent work on dust-gas dynamics in PPDs and discuss implications for planet formation. I first describe the problem of dust sedimentation in PPDs. This process is widely considered as a necessary step towards planetesimal formation. However, turbulence in the disk can stir up dust particles, thereby prevent planetesimal formation. I will discuss how dust can overcome turbulence and sediment by accounting for two-way drag forces between gas and dust. I will then describe how newly born protoplanets continue to interact with its surrounding disk. Such disk-planet interactions may be responsible for substructures such as rings and gaps now commonly observed in real PPDs. I show that planets interacting with a dusty disk can differ significantly from the more frequently studied case of pure gas disks. This may be important for shaping the final architecture of planetary systems. Finally, I will give a preview of upcoming projects that combine disk-planet interaction and dust settling in the context of PPD substructures.