Star Formation, Circumstellar Disks, and Planetary Systems


I am interested in studying the process of star formation, with the aim of determining the ultimate fate of circumstellar disks. CurrenAt present we are faced with compelling evidence that disks similar to the one which must have produced planets around our Sun 4.6 billion years ago exist around many, if not most, newly formed stars. Infrared radiation emitted by particles within the disks as they are warmed by the light of the central star provides clues to the structure of these disks and permits us, via observations of stars in clusters of differing age, to determine the lifetime of these structures. In the past we have investigated whether the continuing collision of planetesimals around these stars generates sufficient quantities of small dust grains to produce infrared emission which persists for hundreds of millions of years. We have also investigated the evolution of the gaseous component of circumstellar disks through millimeter wave ¹² CO observations of young stars. Currently we are using the CorMASS spectrograph to monitor actively accreting T-Tauri stars for variability in both the continuum and line flux in the region where matter moves through the inner few tenths of an AU of the disk and onto the star.