The Spitzer Deep, Wide-Field Survey
  The Spitzer Deep, Wide-Field Survey (SDWFS) is a four-epoch infrared survey
of ten square degrees in the Bootes field of the NOAO Deep Wide-Field Survey
using the IRAC instrument on the Spitzer Space Telescope. SDWFS, a Cycle four
Spitzer Legacy project, occupies a unique position in the area-depth survey
space defined by other Spitzer surveys. The four epochs that make up SDWFS
permit -- for the first time -- the selection of infrared-variable and high
proper motion objects over a wide field on timescales of years. Because of its
large survey volume, SDWFS is sensitive to galaxies out to z~3 with relatively
little impact from cosmic variance for all but the richest systems. The SDWFS
datasets will thus be especially useful for characterizing galaxy evolution
beyond z~1.5. This paper explains the SDWFS observing strategy and data
processing, presents the SDWFS mosaics and source catalogs, and discusses some
early scientific findings. The publicly-released, full-depth catalogs contain
6.78, 5.23, 1.20, and 0.96 x 10e5 distinct sources detected to the average
5-sigma, 4" diameter, aperture-corrected limits of 19.77, 18.83, 16.50, and
15.82 Vega mag at 3.6, 4.5, 5.8, and 8.0 micron, respectively. The SDWFS number
counts and color-color distribution are consistent with other, earlier Spitzer
surveys. At the 6 min integration time of the SDWFS IRAC imaging, more than 50%
of isolated FIRST radio sources and more than 80% of on-axis XBootes sources
are detected out to 8.0 micron. Finally, we present the four highest proper
motion IRAC-selected sources identified from the multi-epoch imaging, two of
which are likely field brown dwarfs of mid-T spectral class.
