Star Formation History in the Richest Clusters of Galaxies
Abstract
We will observe six of the richest Abell clusters in order to determine the star formation histories of their member galaxies. Recent radio studies indicate that the star formation and evolution of cluster galaxies is intimately tied to cluster dynamical state. Our targets were selected by combining our sensitive radio continuum survey of clusters with the SDSS, thereby providing quality imaging and spectroscopic data of hundreds of cluster members. The optical data will be used to determine the kinematics of the clusters, which on the basis of X-ray morphology are separated into three dynamical states: 1) virialized clusters, 2) substructure clusters (including major merger events), and 3) ''protoclusters.'' The importance of the GALEX data is that they will provide a unique look at star formation over 10^9 year timescales, which is the same time range where models for galaxy evolution in the cluster environment predict the most transformation. The excellent sensitivity of GALEX to recent star formation will also extend the radio results down to much lower levels of activity, providing large numbers of objects for use in statistical comparisons among the clusters. Finally, the wide field of view of GALEX will explore activity from the cluster cores out to well past the infall regions. The end goal is a more detailed understanding of the relationship between cluster dynamical state and the evolution of member galaxies.
- Publication:
-
GALEX Proposal
- Pub Date:
- 2005
- Bibcode:
- 2005galx.prop...35M