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.

Based on observations obtained at the Canada-France-Hawaii Telescope (program 03BF12) which is operated by the National Research Council of Canada, the Institut des Sciences de l'Univers of the Centre National de la Recherche Scientifique and the University of Hawaii. Also based on ESO VLT data (program 074.A-0533), and on HST archive data (proposals 5121 and 8683).