The early-type dwarf galaxy population in nearby galaxy clusters

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This project aims at the investigation of the properties of early-type dwarf galaxies in the nearby galaxy clusters Hydra I and Centaurus as well as in the two fossil groups NGC 1132 and NGC 6482. A further goal of this project is a complete spectroscopic census of ultra-compact dwarf galaxies (UCDs) and bright globular clusters in the Hydra I galaxy cluster.Early-type dwarf galaxies as faint as those in the Local Group (M۷<-10 mag) have up to now only been investigated in the nearby clusters Virgo, Fornax and Coma. With our new spectroscopic and photometric observations, which were recently obtained with VLT/VIMOS, VLT/FORSl and Subaru/Suprime-Cam, we will broaden the environmental baseline of former studies in order to study in detail the frequency, the spatial and kinematical distribution, the stellar population content and the global photometric and structural parameters of early-type dwarf galaxies. This will enable us to investigate various formation scenarios and evolutionary models of dwarf galaxies in clusters, such as the possible link of nucleated dwarf galaxies to UCDs. Moreover, the stellar population content of UCDs in Hydra I will be compared with those published for UCDs in Fornax, Virgo and Centaurus in order to extend the current understanding of this peculiar type of objects.The proposed research programme is a continuation of a project which deals with the investigation of early-type dwarf galaxies. It was initiated in 2007 at ESO/Garching for and with the PhD student Ingo Misgeld. Here, support for the final 1.5 years of the entire research programme is requested, so that Ingo Misgeld can complete his PhD thesis at the Universitäts-Sternwarte München (USM) of the Ludwig Maximilians-University (LMU) which provides the ideal environment for the proposed science.