SPITZER INFRARED SPECTROMETER 16 mu m OBSERVATIONS OF THE GOODS FIELDS

We present Spitzer 16 mu m imaging of the Great Observatories Origins Deep Survey (GOODS) fields. We survey 150 arcmin(2) in each of the two GOODS fields (North and South), to an average 3 sigma depth of 40 and 65 mu Jy, respectively. We detect similar to 1300 sources in both fields combined. We validate the photometry using the 3-24 mu m spectral energy distribution of stars in the fields compared to Spitzer spectroscopic templates. Comparison with ISOCAM and AKARI observations in the same fields shows reasonable agreement, though the uncertainties are large. We provide a catalog of photometry, with sources cross-correlated with available Spitzer, Chandra, and Hubble Space Telescope data. Galaxy number counts show good agreement with previous results from ISOCAM and AKARI with improved uncertainties. We examine the 16-24 mu m flux ratio and find that for most sources it lies within the expected locus for starbursts and infrared luminous galaxies. A color cut of S-16/S-24 > 1.4 selects mostly sources which lie at 1.1 < z < 1.6, where the 24 mu m passband contains both the redshifted 9.7 mu m silicate absorption and the minimum between polycyclic aromatic hydrocarbon emission peaks. We measure the integrated galaxy light of 16 mu m sources and find a lower limit on the galaxy contribution to the extragalactic background light at this wavelength to be 2.2 +/- 0.2 nW m(-2) sr(-1).