Satellite quenching was not important for z>1 clusters: most quenching occurred during infall
Abstract
We investigate pre-processing of the galaxy population in the outskirts of 17 galaxy clusters at 0.8<z<1.5 drawn from the GOGREEN and GCLASS surveys. We confirm that the fraction of quiescent galaxies is higher within the clusters' virial radius compared to the 1<R_v<3 infall region, which is itself elevated compared to the field. However, we infer that different quenching modes must occur in the two regions since the quenching efficiencies of the cluster and infall regions have significantly different mass dependencies. Inside 1R_v, galaxies of all stellar masses quench with the same efficiency (similar to clusters in the local Universe), but quenching in the infall region has a strong mass dependence, with the most massive galaxies having the largest quenched fraction excess. We compare the radial distribution of satellite galaxies around massive infall and field galaxies, finding that both are well fit by an NFW profile, but the NFW scale radius of the infall galaxies is 2.8+/-1.6 times that of the field galaxies. This suggests that the massive infall galaxies reside in dark matter halos that are typically 10.2+/-2.8 times more massive than those hosting similar stellar mass galaxies in the field. We interpret these results as evidence that the halos surrounding high-redshift clusters have a top-heavy mass function, which alters the galaxy properties before they become satellites of the clusters.
- Publication:
-
Galaxy Cluster Formation II
- Pub Date:
- June 2021
- DOI:
- 10.5281/zenodo.4974454
- Bibcode:
- 2021gcf2.confE..20W
- Keywords:
-
- galaxy clusters;
- clusters of galaxies;
- galaxy evolution;
- Zenodo;
- Galaxy Cluster Formation community gcf2021