Discovery of a new M 32-like Compact Elliptical galaxy in the halo of the Abell 496 cD galaxy
Discovery of a new M 32-like Compact Elliptical galaxy in the halo of the Abell 496 cD galaxy
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DOI：
10.1051/0004-6361:20077291
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发表时间：
2007-03
影响因子：
6.5
通讯作者：
I. Chilingarian;V. Cayatte;L. Chemin;F. Durret;T. Laganá;C. Adami;É. Slezak
中科院分区：
文献类型：
--
作者：
I. Chilingarian;V. Cayatte;L. Chemin;F. Durret;T. Laganá;C. Adami;É. Slezak
目标：“紧凑椭圆”是如此罕见，需要寻找M32类似物，以确保这一类的存在。方法：我们在这里报告的发现A496 cE，一个M32的双胞胎在集群阿贝尔496，位于晕的中央cD。结果：基于CFHT和HST成像，我们发现A496 cE的光分布需要两个分量的拟合：Sersic凸起和指数盘。使用ESO-VLT FLAMES/Giraffe摄谱仪获得的A496 cE光谱可以用以老星为主的恒星合成光谱来拟合，具有高的[Mg/Fe]值和速度色散。结论：简要讨论了cD星系对A496 cE的捕获及其盘的潮汐剥离。
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.