Probing galaxy formation in the local universe: dwarf irregular galaxies and their globular cluster systems as galactic building blocks

星系的组装历史仍然是当今天体物理学中最迫切需要解决的问题之一。在目前流行的分级合并方案中，大质量星系被认为是通过大量合并而增长的。矮小不规则星系(DIRR)被广泛认为与它们的银河系前积木最相似。波恩大学阿格兰德天文学研究所(阿尔法)的高水平和多样性天文研究将为这一项目提供良好的环境。

The assembly history of galaxies remains one of the most pressing questions in astrophysics to be solved today. In the currently popular hierarchical merging scenario, massive galaxies are believed to grow via numerous mergers. Dwarf irregular (dIrr) galaxies are widely regarded as being closest in resemblence to their pre-galactic building blocks. Hence, a study of the old globular clusters (GCs) in dIrr galaxies (whose properties reflect the physical conditions at the time of their early formation) and a comparison with GCs in massive galaxies can be used to quantify the contribution of dlrr galaxies to the assembly of massive present-day galaxies and their globular cluster systems (GCS). An excellent example for the need of such a study is the GCS of our Galaxy, because it is found to harbor a sub-population of GCs whose properties (colors, luminosities, horizontal branch morphologies, structural parameters and orbital kinematics) suggest that they might have formed in low-mass satellites and were later incorporated into the Milky Way GCS.The goal of the project is to investigate the properties of GCs in dlrr galaxies. This will allow to 1) constrain the contribution of dlrrs to the assembly of GCSs in massive galaxies; 2) probe the origin of chemically peculiar GCs in our Galaxy; 3) investigate the puzzling mass-metallicity relation among metal-poor GCs; 4) assess horizontal branch morphologies for GCs in dlrrs.Here support to achieve the science goals of the research programme is requested. The high level and diversity of astronomical research at the Argelander Institut für Astronomie (AlfA) of the University of Bonn will provide an excellent environment for this project.