Probing the Fates of Stars With White Dwarfs in Open Star Clusters
Kurtis Williams
University of Texas

Stars end their evolution by either forming a white dwarf remnant or exploding as core collapse supernova. Which fate a star experiences is thought to depend primarily on its mass, with the dividing line lying somewhere between six and ten solar masses. The precise value of this critical mass has a great impact on the number of supernovae and on the chemical enrichment of stellar populations. I will present studies of the white dwarf populations of intermediate age (100 Myr to 1 Gyr) open star clusters that provide observational evidence on the dividing line between the white dwarf and supernova fates of stars. These same data also help to define the initial-final mass relation for white dwarfs. I will also discuss the systematic issues that are currently limiting the observational constraints on the critical mass for supernovae. Finally, I will consider some tenuous evidence of a link between the intriguing hot carbon atmosphere white dwarfs and the highest mass progenitors of white dwarfs.

Date:	Jeudi, 19 novembre 2009
Time:	11:30
Where:	Université de Montréal
	Pavillon Roger-Gaudry, Local D-460
Contact:	Patrick Dufour