Discovery of a new M 32-like "compact elliptical" galaxy in the halo of the Abell 496 cD galaxy

Abstract

Aims. "Compact ellipticals" are so rare that a search for M 32 analogs is needed to ensure the very existence of this class. Methods. We report here the discovery of A496cE, a M 32 twin in the cluster Abell 496, located in the halo of the central cD. Results. Based on CFHT and HST imaging we show that the light profile of A496cE requires a two component fit: a Sérsic bulge and an exponential disc. The spectrum of A496cE obtained with the ESO-VLT FLAMES/Giraffe spectrograph can be fit by a stellar synthesis spectrum dominated by old stars, with high values of [Mg/Fe] and velocity dispersion. Conclusions. The capture of A496cE by the cD galaxy and tidal stripping of most of its disc are briefly discussed. © ESO 2007.