2022MNRAS.515.5479B

We model satellite quenching at z ∼ 1 by combining 14 massive (10^13.8 < M_halo/M_⊙ < 10¹⁵) clusters at 0.8 < z < 1.3 from the GOGREEN and GCLASS surveys with accretion histories of 56 redshift-matched analogues from the IllustrisTNG simulation. Our fiducial model, which is parametrized by the satellite quenching time-scale (τ_quench), accounts for quenching in our simulated satellite population both at the time of infall by using the observed coeval field quenched fraction and after infall by tuning τ_quench to reproduce the observed satellite quenched fraction versus stellar mass trend. This model successfully reproduces the observed satellite quenched fraction as a function of stellar mass (by construction), projected cluster-centric radius, and redshift and is consistent with the observed field and cluster stellar mass functions at z ∼ 1. We find that the satellite quenching time-scale is mass dependent, in conflict with some previous studies at low and intermediate redshift. Over the stellar mass range probed (M_⋆ > 10¹⁰ M_⊙), we find that the satellite quenching time-scale decreases with increasing satellite stellar mass from ∼1.6 Gyr at 10¹⁰ M_⊙ to ∼0.6-1 Gyr at 10¹¹ M_⊙ and is roughly consistent with the total cold gas (HI + H₂) depletion time-scales at intermediate z, suggesting that starvation may be the dominant driver of environmental quenching at z < 2. Finally, while environmental mechanisms are relatively efficient at quenching massive satellites, we find that the majority ($\sim 65{\!-\!}80{{\ \rm per\ cent}}$) of ultra-massive satellites (M_⋆ > 10¹¹ M_⊙) are quenched prior to infall.