The Complete Spitzer Survey of Stellar Structure in Galaxies (CS4G)

The Spitzer Survey of Stellar Structure in Galaxies (S4G) together with the Early Type Extension (ETG) stands as the most extensive dataset of deep, uniform mid-infrared imaging for a sample of 2817 nearby (< 40 Mpc) galaxies. The radio-derived velocity criteria miss 425 disc galaxies without 21 cm HI detection but with optical velocities within the criteria. We collected 3.6 μm and i-band images from archival data from different surveys and completed it with new observations for these missing disc galaxies. Along with its last extension, we seek to finish the survey and present the Complete Spitzer Survey of Stellar Structure in Galaxies (CS4G) containing a complete sample of 3242 galaxies with consistent imaging, surface brightness profiles and photometric parameters. Following the original strategy of the survey, we produce masks, surface brightness profiles, and curves of growth using reduced and masked 3.6 μm and i-band images. We derive the following integrated quantities from these profiles: total magnitudes stellar masses, concentration parameters, and galaxy size metrics. We derive a recipe for the conversion between optical i-band and 3.6 μm. We present new morphological revised T -types and we showcase mid-IR scaling relations among the stellar mass, Galaxy size, concentration index, and morphological type. The converted photometric parameters from the i-band images yield consistent measurements with the previous original sample (S4G) and extension (ETG) in the band 3.6 μm. The average galaxy in the disc galaxy sample is 24 % of the average mean of galaxies with a similar T-type in the original S4G with a 34% smaller size and similar concentration. We improve the completeness of the sample by incorporating 425 disc galaxies into the original dataset. This addition constitutes 15% of the total previous sample (S4G+ETG). However, within the lower mass bin (M_∗ < 10^9 M_⊙), the disc Galaxy extension increases the sample by 30%. We make the images, and surface brightness profiles available to the community together with the conjunct catalogue of the whole CS4G dataset with consistent photometric measurements for 3242 galaxies. The CS4G includes at least 99% of the nearby galaxies. The CS4G will enable a wide set of investigations into galaxy structure and evolution, and complement optical and near-IR imaging to be obtained in coming years with Euclid, LSST and other projects.