Angular clustering of galaxies at 3.6 microns from the Spitzer Wide-area Infrared Extragalactic (SWIRE) Survey

Abstract

We present the first analysis of large-scale clustering from the Spitzer Wide-area Infrared Extragalactic legacy survey (SWIRE). We compute the angular correlation function of galaxies selected to have 3.6 m fluxes brighter than 32 Jy in three fields totaling 2 deg2 in area. In each field we detect clustering with a high level of significance. The amplitude and slope of the correlation function is consistent between the three fields and is modeled as w() ¼ A1 with A ¼ (0:6 0:3) ; 10 3; ¼ 2:03 0:10. With a fixed slope of ¼ 1:8, we obtain an amplitude of A ¼ (1:7 0:1) ; 10 3. Assuming an equivalent depth of K 18:7 mag we find that our errors are smaller but our results are consistent with existing clustering measurements in K-band surveys and with stable clustering models. We estimate our median redshift z ’ 0:75, and this allows us to obtain an estimate of the three-dimensional correlation function (r), for which we find r0 ¼ 4:4 0:1 h 1 Mpc