11 March 2004

Speaker: Brad Hansen (UCLA)

Title: The White Dwarf cooling sequence in the Globular Cluster Messier 4

Abstract: I will discuss the results of a very deep HST observation of the globular cluster M4, with special focus on the white dwarf cooling sequence. I will discuss how one can place constraints on the cluster age by fitting white dwarf cooling models to the observed cooling sequence and explore the various systematic uncertainties of this cluster dating method.

References for students:

1. Hansen et al (2002) ApJ 574, L155
2. Hansen et al (2004) /astro-ph/0401443