Spitzer Space Telescope - General Observer Proposal #30823


Pushing the Far-IR Capability of Spitzer in the Study of High-Redshift
ULIRGs

Principal Investigator: Charles Dowell
           Institution: Jet Propulsion Laboratory

Co-Investigators: 
Colin Borys, University of Toronto (Canada)                           
Eiichi Egami, University of Arizona                                   
Michael Zemcov, Cardiff University (UK)                               

Science Category: high-z galaxies (z>0.5) 
 Observing Modes: MipsPhot 
  Hours Approved: 60.4 

Abstract:
We propose deep MIPS 70  and 160  micron observations of a sample of
submillimeter-selected high-redshift ultraluminous infrared galaxies
(ULIRGs).  For the first time, we will explore the diversity of their
far-infrared spectral distributions -- in particular, on the Wien side
of the graybody peak -- and measure accurately the integrated infrared
luminosity.  The targets are drawn from a sample of 850  micron
sources at z > 1 amplified by foreground galaxy clusters, where the
lensing allows us to measure galaxies which would otherwise be too
faint for detection and may also lower the confusion noise.  Our
program is complemented by ground-based 350  micron imaging, which
quantifies the graybody spectrum.