March 9, 2000 CfA Colloquium


Title: Kinematics of the Galaxy and Halo Substructure

Speaker: Tim Beers

Abstract: The database of stars in the halo and thick disk of the Galaxy is growing rapidly, both in the numbers of objects, and in the wealth of information which is available for each star. I report on a newly revised catalog of non-kinematically-selected metal-deficient stars which includes radial velocity, distance, and abundance information for some 2000 stars. Newly obtained proper motions are now available for some 1300 of these objects. For the FIRST TIME, we can draw a kinematically-unbiased picture of the thick disk and halo populations of the Milky Way. I also discuss searches in this catalog (in angular momentum space) for the presence of predicted halo debris trails quite likely to be associated with collisions of the disk of the Milky Way with a previous generation of dwarf-like galaxies.

Reference for students: Beers & Sommer-Larsen (1995), ApJS, 96, 175.
Lunch on Friday 3/10 at 12:00 pm in Pratt.