Are Globular Clusters the Remnant Nuclei of Progenitor Disk Galaxies?
نویسنده
چکیده
The globular cluster system of a typical spheroidal galaxy makes up about 0.25% of the total galaxy mass (McLaughlin 1999). This is roughly the same mass fraction as contained in the nuclear star cluster (or stellar nucleus) present in most nearby low-mass galaxies. Motivated by this “coincidence”, this Letter discusses a scenario in which globular clusters of present-day galaxies are the surviving nuclei of the dwarf galaxies that according to the hierarchical merging paradigm of galaxy formation constitute the “building blocks” of present-day massive galaxies. This scenario, which was first suggested by Freeman (1993), has become more attractive recently in the light of studies that demonstrate a complex star formation history in a number of massive globular clusters. Subject headings: globular clusters: general
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