The buildup of E–S0 galaxies at z < 2 from pure luminosity evolution models

Abstract

Considering that the recent history of E-S0’s can be approximated by Pure Luminosity Evolution (PLE), we have examined a set of PLE models in order to de-limit the epoch in which the majority of the red galaxy population moved away this simple evolution framework. The models assume that they were assembled and formed most of their stars at a given formation redshift (zf), and that they have evolved without merging or substantial dust obscuration since then. Comparing the model predictions with real data, we conclude that most of E-S0’s at low and inter-mediate luminosities must have been progressively built up at 1 < z < 2, being the bulk of formation at z ∼ 1.5, as recently claimed by several observational studies.