Vortices in Protoplanetary Disks: Their Role in Angular Momentum Transport and Planetesimal Formation

University Of California-Berkeley, Berkeley CA

Investigators

Abstract

" Vortices in Protoplanetary Disks: Their Role in Angular Momentum Transport and Planetesimal Formation " AST- 0098465 From local observation, it is known that the Sun and the solar system have effectively the same age and that both are likely to have formed through the collapse of a protostellar disk of dust and gas. While infalling material is necessary for the collapse to take place, angular momentum must at the same time be transported outwards if a stable star is to be formed. As a prelude to planet formation, a mechanism must be found that will build kilometer-sized planetesimals from sub-centimeter sized dust grains. During the period of this award, both problems will be addressed by postulating that the formation of small vortices could simultaneously produce the necessary mass and momentum transport for star formation and at the same time be sweeping dust into their interiors where it can settle and form planetesimals. Following on from the work he has done in explaining the structures which are seen in the atmosphere of the planet Jupiter, the PI and his students will be adapting his mathematical procedures to a study of protoplanetary disks, which, he believes, are unlikely to be either featureless, laminar or filled with homogeneous turbulence. He expects to show that small vortices are likely to thrive in such a disk and that they, rather than large-scale turbulence are likely to be responsible for transport within a cool protoplanetary disk. These same vortices are able to entrap the dust grains and aid planetesimal formation.