The Spitzer-South Pole Telescope Deep Field: Survey Design and IRAC Catalogs

TL;DR

The SSDF survey is a large, multi-wavelength observational project using Spitzer IRAC to catalog millions of extragalactic sources over 94 square degrees, aiding studies of galaxy clusters and baryon distribution.

Contribution

This paper details the survey design, data processing, and provides the first extensive IRAC source catalogs for the SSDF, the largest IRAC survey outside the Milky Way midplane.

Findings

Catalogs contain approximately 5.5 and 3.7 million sources.

Sources are primarily galaxies, detected down to 19.0 and 18.2 Vega mag.

Survey covers 94 square degrees with multi-wavelength data integration.

Abstract

The Spitzer-South Pole Telescope Deep Field (SSDF) is a wide-area survey using Spitzer's Infrared Array Camera (IRAC) to cover 94 square degrees of extragalactic sky, making it the largest IRAC survey completed to date outside the Milky Way midplane. The SSDF is centered at 23:30,-55:00, in a region that combines observations spanning a broad wavelength range from numerous facilities. These include millimeter imaging from the South Pole Telescope, far-infrared observations from Herschel/SPIRE, X-ray observations from the XMM XXL survey, near-infrared observations from the VISTA Hemisphere Survey, and radio-wavelength imaging from the Australia Telescope Compact Array, in a panchromatic project designed to address major outstanding questions surrounding galaxy clusters and the baryon budget. Here we describe the Spitzer/IRAC observations of the SSDF, including the survey design, observations, processing, source extraction, and publicly available data products. In particular, we present two band-merged catalogs, one for each of the two warm IRAC selection bands. They contain roughly 5.5 and 3.7 million distinct sources, the vast majority of which are galaxies, down to the SSDF 5-sigma sensitivity limits of 19.0 and 18.2 Vega mag (7.0 and 9.4 microJy) at 3.6 and 4.5 microns, respectively.