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arXiv · 1610.08058

Evidence for strong evolution in galaxy environmental quenching efficiency between z = 1.6 and z = 0.9

Julie B. Nantais·Adam Muzzin·Remco F. J. van der Burg·Gillian Wilson·Chris Lidman·Ryan Foltz·Andrew DeGroot·Allison Noble·Michael C. Cooper·Ricardo Demarco
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Abstract

We analyse the evolution of environmental quenching efficiency, the fraction of quenched cluster galaxies that would be star-forming if they were in the field, as a function of redshift in 14 spectroscopically confirmed galaxy clusters with 0.87 < z < 1.63 from the Spitzer Adaptation of the Red-Sequence Cluster Survey (SpARCS). The clusters are the richest in the survey at each redshift. Passive fractions rise from $42_{-13}^{+10}$\% at z ~ 1.6 to $80_{-9}^{+12}$\% at z ~ 1.3 and $88_{-3}^{+4}$\% at z < 1.1, outpacing the change in passive fraction in the field. Environmental quenching efficiency rises dramatically from $16_{-19}^{+15}$ at z ~ 1.6 to $62_{-15}^{+21}\% at z ~ 1.3 and $73_{-7}^{+8}$\% at z $\lesssim$ 1.1. This work is the first to show direct observational evidence for a rapid increase in the strength of environmental quenching in galaxy clusters at z ~ 1.5, where simulations show cluster-mass halos undergo non-linear collapse and virialisation.

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Julie B. Nantais, Adam Muzzin, Remco F. J. van der Burg, Gillian Wilson, Chris Lidman, Ryan Foltz, Andrew DeGroot, Allison Noble, Michael C. Cooper, Ricardo Demarco. 2016-10-25. Evidence for strong evolution in galaxy environmental quenching efficiency between z = 1.6 and z = 0.9. https://doi.org/10.1093/mnrasl/slw224

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