The Evolutionary Status of Early-Type Galaxies in Abell 2390

Abstract

We explore the evolution of the early-type galaxy population in the rich cluster Abell 2390 at z = 0.23. For this purpose, we have obtained spectroscopic data of 51 elliptical and lenticular galaxies with MOSCA at the 3.5 m telescope on Calar Alto Observatory. As our investigation spans both a broad range in luminosity (−22. 3 ≤ M _B ≤ −19.3) and a wide field of view (10′ x 10′), the environmental dependence of different formation scenarios can be analysed in detail as a function of radius from the cluster center. In this paper, we present first results on the Faber-Jackson relation and, for a subsample of 14 galaxies with morphological and structural parameters from HST, we also investigate the evolution of the Kormendy relation and the Fundamental Plane. We find a mild luminosity evolution of the early-type galaxies in Abell 2390: our objects are on average brighter by m-0304; _B ∼ 0.4 mag.