Tracing luminous infrared galaxy populations through cluster evolution in a cosmological mock redshift survey

Abstract

We present GARDENS-Wide, a new 100 square degree mock redshift survey of the dusty star-forming galaxy population based on the MultiDark-Planck 2 dark-matter halo simulation. The mock reproduces observed multiwavelength number counts at 500 $\mu$m, 1.1, 1.4 and 2.0 mm. The large simulated area enables us to identify gravitationally bound systems, trace their assembly histories, and quantify the redshift evolution of their galaxy content and structural extent. We find strong evolution in the fractional contribution of galaxy populations within cluster progenitors. Star-forming galaxies account for ~35 per cent of members at low redshift, increasing to 60-65 per cent at $z\sim 2$ and declining to ~20 per cent by $z\sim 5$. LIRGs contribute ~20-40 per cent, peaking near $z\sim 2$, while ULIRGs remain subdominant and HyLIRGs are rare. We measure proto-cluster radii as the maximum 3D comoving distance from the central halo to the most distant member halo. Proto-clusters contract significantly over cosmic time, from >20 comoving Mpc at high redshift to a few Mpc at $z\sim 0$. ULIRGs become increasingly centrally concentrated at $z>1.5$ in rich proto-clusters. We provide observational predictions for the TolTEC Large-Scale Structure survey.

16 pages, 13 figures. Submitted to Monthly Notices of the Royal Astronomical Society