Discovery of a new M 32 - like “ Compact Elliptical ” galaxy in the halo of the Abell 496 cD galaxy ⋆
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چکیده
Aims. " Compact ellipticals " are so rare that a search for M32 analogs is needed to ensure the very existence of this class. Methods. We report here the discovery of A496cE, a M32 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.
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تاریخ انتشار 2007