CfA Colloquium: September 26, 2002

Speaker: Robin Ciardullo (Penn State)

Title: Planetary Nebulae and Intracluster Stars

Abstract: Planetary nebulae are unique and powerful tools for extragalactic astronomy and cosmology. They are excellent standard candles, ideal test particles for dynamical studies, and a valuable probe of stellar populations. I will review some recent results from extragalactic planetary nebulae, especially those dealing with the subject of intracluster stars. I will show that in the Virgo Cluster, the intracluster stars are relatively metal-rich (0.8 < [Fe/H] < -0.2), distributed in an elongated fashion along our line-of-sight, and make up 10 - 20% of the stellar mass. I will contrast our Virgo measurements with preliminary results from the Fornax Cluster and M81 Group, and discuss the implications the data have for cluster evolution scenarios.

Reference for students:
Ciardullo et al astro-ph/0206177
Durrell et al 2002 ApJ 570, 119
Ciardullo et al 2002 ApJ 566, 784