21 October 2004

Speaker: Knut Olsen (Cerro Tololo Inter-American Observatory )

Title: Globular Clusters and the Disks of Nearby Galaxies

Abstract: What can globular clusters and the star formation histories of nearby galaxies teach us about the formation of galactic disks? I will motivate this question with a brief review of the old globular clusters of the LMC, but also present evidence that the LMC's disk is disturbed, complicating interpretation of its globular cluster system properties. I will proceed to describe our discovery and analysis of metal-poor globular clusters in four Sculptor group galaxies, whose ages and metallicities appear similar to the globular clusters of the Milky Way, yet whose kinematics place them in disks rather than halos. I will conclude with a brief derivation of the star formation histories of M31's bulge and disk, using recently obtained Gemini N+Altair adaptive optics data and existing data from HST+NICMOS. Taken as a whole, these data provide insight into the formation mechanism for disks and a rough estimate of the timescale of disk formation.

Video of the Presentation (Talks can be viewed with RealPlayer. Free download is available from www.real.com )

References for students:

1. Olsen et al. 1998, MNRAS, 300, 665
2. Olsen et al. 2004, AJ, 127, 2674