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arXiv · astro-ph/0703322

Discovery of a new M32-like "Compact Elliptical" galaxy in the halo of the Abell 496 cD galaxy

Igor Chilingarian·Veronique Cayatte·Laurent Chemin·Florence Durret·Tatiana Ferraz Lagana·Christophe Adami·Eric Slezak
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Abstract

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 Sersic 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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Igor Chilingarian, Veronique Cayatte, Laurent Chemin, Florence Durret, Tatiana Ferraz Lagana, Christophe Adami, Eric Slezak. 2007-03-13. Discovery of a new M32-like "Compact Elliptical" galaxy in the halo of the Abell 496 cD galaxy. https://doi.org/10.1051/0004-6361%3A20077291

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