Mass-loss Geometry and Disks

Background

The Common Envelope (CE) interaction imparts a defined axis of symmetry to the giant mass-loss. Large, dusty disks are likely to form during such interaction. If during the interaction the companion does not eject the envelope it will eventually be tidally destroyed. This too can create a compact disk around the primary core. Accretion disks can also form around the companions to giant stars, or, later, to post-CE WDs. There is no doubt that disks play a huge role in the evolution of these systems.

My role

With Jason Nordhaus (University of Rochester and Princeton) we are investigating the nature of disks around evolved stars. Jason is an expert in this subject and has designed observational tests for mass-loss geometry.

Jason and I are also working together with Jay Farihi (University of Leicester) on the effects of disks on period evolution with an intent to explain intermediate period post-AGB binaries. We will present the initial results of this work at the 16th European Workshop on White Dwarfs.

With You-Hua Chu and students we are giving some thought to the disks that seem to be common around hot central stars of PN and that might or might not be related to the so called debris disks recently found around WDs.

Publicatons

Towards a Spectral Technique for Determining Material Geometry Around Evolved Stars: Application to HD 179821
Nordhaus J., Minchev, I., Sargent, B., Forrest, W., Blackman, E.G., De Marco, O., Kastener, J., Balick, B., Frank, A., 2008, MNRAS, in press

Last Update: 15 January 2004