Astrophysics Research Seminar: Dr Claire Davies, University of Exeter

Dr Claire Davies, Department of Physics & Astronomy, University of Exeter, will be presenting a seminar on her research. All are welcome to attend.

Disk-bearing young stellar objects at high angular resolution Abstract: Angular momentum conservation during the gravitational collapse of molecular cloud cores is expected to result in the formation of a disk of gas and dust perpendicular to the bulk rotation axis. Direct observations of the innermost au of these disks allow us to probe the inner disk structure and its impact on the bulk disk structural evolution (one product of which is potentially the formation of planetary systems).

For the closest young stellar objects (YSOs), these disk regions subtend an angle on the order of 10s of milliarcseconds at most - a distance scale only accessible to infrared interferometry. In the first section of my talk, I will focus on the Center for High Angular Resolution Astronomy (CHARA) survey of YSOs. In particular, I will present results recently published for Herbig Ae/Be YSOs HD142666, V1295 Aql and MWC 275 as well as preliminary results for T Tauri YSOs SU Aur and RY Tau. The 330 m baselines of CHARA have enabled us to spatially resolve the inner dust rims of the disks of these objects, revealing e.g. a range of grain growth efficiencies, the presence of additional optically thick material interior to the dust sublimation rim and additional physical processes including dusty disk winds.

The second section of my talk will shift focus to the relative alignment of stars and their disks and how the typical Kant-Laplace nebula hypothesis concept of a single star with a disk around its equator is being brought into question by recent high angular resolution observations. In particular, I will discuss my recently accepted publication looking at how photometric variability of YSOs with spatially-resolved disks can be used to assess whether the degree of alignment present in the solar system can be considered to be normal.

Host: Dr Sven Van Loo