Substructure in dwarf spheroidals – a star cluster connection?

Abstract

Abstract. The observational evidence for kinematic substructure in Local Group dSphs is reviewed. The properties of these substructures are consistent with their being disrupted star clusters. The persistence of cold substructure argues strongly against the presence of dark matter cusps in the haloes of dSphs. A formation scenario for dSphs is described involving the merger of star clusters in the potential well of a low-mass dark matter halo.

A possible formation scenario for dwarf spheroidal galaxies – I. Fiducial model

“…their dissolution due to gas expulsion, may explain the formation of classical dSph galaxies. In our scenario we simulate SCs within a DM halo , as a natural extension of the work of Fellhauer & Kroupa (2002); Wilkinson et al (2005); Praagman et al (2010). The star clusters form with low SFE and, thus, are designed to dissolve inside the DM halo to form the luminous component of the dSph galaxy.…”