Constraining the evolution of CII intensity through the end stages of reionization

Abstract

We combine available constraints on the local CII 158 $\mu$m line luminosity function from galaxy observations (Hemmati et al. 2017), with the evolution of the star-formation rate density and the recent CII intensity mapping measurement in Pullen et al. (2018, assuming detection), to derive the evolution of the CII luminosity - halo mass relation over $z \sim 0-6$. We develop convenient fitting forms for the evolution of the CII luminosity - halo mass relation, and forecast constraints on the CII intensity mapping power spectrum and its associated uncertainty across redshifts. We predict the sensitivities to detect the power spectrum for upcoming PIXIE-, STARFIRE-, EXCLAIM-, CONCERTO-, TIME- and CCAT-p-like surveys, as well as possible future intensity mapping observations with the ALMA facility.