Spitzer Space Telescope - General Observer Proposal #20754


The Stellar Mass of High Redshift RCS Galaxy Clusters

Principal Investigator: Erica Ellingson
           Institution: University of Colorado

Co-Investigators: 
Howard Yee, University of Toronto                                     
Michael Gladders, Carnegie Observatories                              
Kris Blindert, University of Toronto                                  
Adam Muzzin, University of Toronto                                    
Tracy Webb, Leiden Observatory                                        
Henk Hoekstra, University of Victoria                                 
David Gilbank, University of Toronto                                  

Science Category: galaxy clusters and groups 
 Observing Modes: IracMap 
  Hours Approved: 15.3 

Abstract:
We propose IRAC observations of a sample of 42 galaxy clusters at
z>0.5 drawn from the Red-Sequence Cluster Survey (RCS).  These
observations will be used to calibrate the optical richness of
clutsters in the RCS surveys to stellar mass.  Extensive
multiwavelength observations of the sample will then allow us to
calculate the cluster mass function to z~1, providing important
constraints on the nature of dark energy and its effect on the
formation on large scale structure.  We will also use these
observations to form a stellar-mass limited sample of cluster galaxies
which will allow us to address outstanding questions about the
evolution of galaxies in dense cluster environments.  In particular,
we will identify whether the well-known Butcher-Oemler effect is
caused primarily by normal star forming galaxies falling into the
cluster, or by dwarf galaxies undergoing strong starbursts within the
cluster environment.