The early-type dwarf galaxy population in nearby galaxy clusters

该项目的目的是调查附近星系团Hydra I和Centaurus以及两个化石群NGC 1132和NGC 6482中早期型矮星系的性质。这个项目的另一个目标是对Hydra I星系团中的超致密矮星系（UCD）和明亮的球状星团进行全面的光谱普查。到目前为止，像本星系群中的那些（M ≥-10等）一样暗淡的早期型矮星系只在附近的室女座、天炉座和后发座中被研究过。我们将利用VLT/VIMOS、VLT/FORS 1和Subaru/Suprime-Cam最近获得的新的光谱和光度观测，扩大以前研究的环境基线，以便详细研究早型矮星系的频率、空间和运动学分布、恒星种群含量以及全球光度和结构参数。这将使我们能够研究星系团中矮星系的各种形成情景和演化模型，例如有核矮星系与UCD的可能联系。此外，Hydra I的UCDs的恒星人口含量将与Fornax，Virgo和Centaurus的UCDs进行比较，以扩大目前对这种特殊类型物体的了解，拟议的研究计划是一个涉及早期类型矮星系调查的项目的继续。它于2007年在ESO/Garching为博士生Ingo Misgeld发起。在这里，需要对整个研究计划的最后1.5年提供支持，以便Ingo Misgeld能够在路德维希马克西米利安大学（LMU）的Universitäts-Sternwarte München（USM）完成他的博士论文，这为拟议的科学提供了理想的环境。

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.