* Astronomy

Title: The Spitzer Deep, Wide-Field Survey
Authors: M. L. N. Ashby, D. Stern, M. Brodwin, R. Griffith, P. Eisenhardt, S. Kozlowski, C. S. Kochanek, J. J. Bock, C. Borys, K. Brand, M. J. I. Brown, R. Cool, A. Cooray, S. Croft, A. Dey, D. Eisenstein, A. H. Gonzalez, V. Gorjian, N. A. Grogin, R. J. Ivison, J. Jacob, B. T. Jannuzi, A. Mainzer, L. A. Moustakas, H. J. A. Rottgering, N. Seymour, H. A. Smith, S. A. Stanford, J. R. Stauffer, I. Sullivan, W. van Breugel, S. P. Willner, E. L. Wright

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 catalogues, and discusses some early scientific findings. The publicly-released, full-depth catalogues 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 colour-colour 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.

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