PACS Evolutionary Probe - A guaranteed time key programme survey of the extragalactic sky

Dieter Lutz (Max Planck Institut fuer E. Physik)

We describe a key programme using the unprecedented sensitivity and spatial resolution of Herschel for a comprehensive far-infrared photometric survey of the extragalactic sky. Blank field surveys using PACS at 170, 110 and 75 μm are supplemented with targeted observations of massive z ~ 1 clusters and lensing clusters. We will resolve the bulk of the Cosmic Infrared Background, determine the nature of its constituent sources and trace the evolution of dust-obscured star formation. Our survey will study the evolution of galaxies and AGN over a wide range of redshifts and in environments of different density, and provide the crucial far-infrared measurements lacking for a full understanding of intermediate and high redshift galaxy populations previously identified at other wavelengths. We have chosen fields with excellent multi-wavelength coverage enabling both rapid science results and a lasting legacy value. This survey is coordinated with Herschel/SPIRE observations of the same fields in a Key programme submitted by the SPIRE SAG 1.