Spitzer Space Telescope - General Observer Proposal #3699


Measuring the Mass, SFR, and Ages of Galaxies Within the z=2.38
Filament

Principal Investigator: James Colbert
           Institution: Spitzer Science Center

Co-Investigators: 
Harry Teplitz, Spitzer Science Center                                 
Povilas Palunas, University of Texas, Austin                          
Gerard Williger, John Hopkins University                              
Bruce Woodgate, Goddard Space Flight Center                           
Paul Francis, Australian National University                          

Science Category: high-z galaxies (z>0.5) 
 Observing Modes: IracMap MipsPhot 
  Hours Approved: 20.6 

Abstract:
We propose to obtain Spitzer images of the central 25x15 arcminutes of
a z=2.38 filament of Lya-emitters.  As the largest structure known
above z=2, it represents a strong opportunity to test the predictions
of hierarchical CDM models at high density.  By combining IRAC and
MIPS 24 micron observations, we will obtain ages, dust content, star
formation rates, and masses for the Lya-emitters.  We will also search
the filament for the reddened star-forming galaxies which are
predicted to cluster in higher density regions, such as the
ultraluminous infrared galaxies (ULIGs).  This field is also home to
four (of 8 known) members of a recently discovered new class of
object, the high-redshift extended Lya "blob''.  These Lya blobs may
directly show the formation of galaxies via the infall of intracluster
gas or the outflow of enriched gas into the ICM, depending on their
origin.  Our IRAC and MIPS 24 micron observations can distinguish
between the various models for the energy source that powers these
objects.