THE SPITZER-IRAC/MIPS EXTRAGALACTIC SURVEY (SIMES) IN THE SOUTH ECLIPTIC POLE FIELD

摘要

We present the Spitzer-IRAC/MIPS Extragalactic survey (SIMES) in the South Ecliptic Pole field. The large area covered (7.7 deg(2)), together with one of the lowest Galactic cirrus emissions in the entire sky and a very extensive coverage by Spitzer, Herschel, Akari, and GALEX, make the SIMES field ideal for extragalactic studies. The elongated geometry of the SIMES area (approximate to 4: 1), allowing for significant cosmic variance reduction, further improves the quality of statistical studies in this field. Here we present the reduction and photometric measurements of the Spitzer/IRAC data. The survey reaches depths of 1.93 and 1.75 mu Jy (1 sigma) at 3.6 and 4.5 mu m, respectively. We discuss the multiwavelength IRAC-based catalog, completed with optical, mid-, and far-IR observations. We detect 341,000 sources with F-3.6 mu m >= 3 sigma. Of these, 10% have an associated 24 mu m counterpart, while 2.7% have an associated SPIRE source. We release the catalog through the NASA/IPAC Infrared Science Archive. Two scientific applications of these IRAC data are presented in this paper. First, we compute integral number counts at 3.6 mu m. Second, we use the [3.6]-[4.5] color index to identify galaxy clusters at z > 1.3. We select 27 clusters in the full area, a result consistent with previous studies at similar depth.