Formation of ultra-compact dwarf galaxies: tests of the galaxy threshing scenario in Fornax
نویسندگان
چکیده
This paper investigates the possibility that ultra-compact dwarf (UCD) galaxies in the Fornax cluster are formed by the threshing of nucleated, early-type dwarf galaxies (hereafter dwarf galaxies). Similar to the results of Côté et al. for the Virgo cluster, we show that the Fornax cluster observations are consistent with a single population in which all dwarfs are nucleated, with a ratio of nuclear to total magnitude that varies slowly with magnitude. Importantly, the magnitude distribution of the UCD population is similar to that of the dwarf nuclei in the
منابع مشابه
Galaxy threshing and the formation of ultra-compact dwarf galaxies
Recent spectroscopic and morphological observational studies of galaxies around NGC 1399 in the Fornax Cluster (Drinkwater et al. 2000b) have discovered several ‘ultra-compact dwarf’ galaxies with intrinsic sizes of ∼ 100 pc and absolute B band magnitudes ranging from −13 to −11 mag. In order to elucidate the origin of these enigmatic objects, we perform numerical simulations on the dynamical e...
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