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

探测本地宇宙中的星系形成：矮不规则星系及其作为星系构建块的球状星团系统

• 批准号: 98116682
• 负责人: Dr. Iskren Y. Georgiev
• 金额: --
• 依托单位: European Space Agency
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2009
• 资助国家: 德国
• 起止时间: 2008-12-31 至 2012-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/98116682?language=en
• 关键词: Probing; galaxy; formation; local; universe

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.

星系的聚集历史是天体物理学中最迫切需要解决的问题之一。在目前流行的分层合并方案中，大质量星系被认为是通过多次合并而成长的。矮不规则星系（dIrr）被广泛认为是最接近它们的前星系建筑块。因此，研究dIrr星系中的旧球状星团（GC）（其性质反映了它们早期形成时的物理条件），并与大质量星系中的GC进行比较，可以用来量化dlrr星系对大质量现代星系及其球状星团系统（GCS）的贡献。一个很好的例子，需要这样的研究是我们的银河系的GCS，因为它被发现窝藏GC的一个子群的属性（颜色，光度，水平分支形态，结构参数和轨道运动学）表明，他们可能已经形成在低质量的卫星，后来被纳入银河系GCS。这将允许1）限制dlrrs对大质量星系中GCs组装的贡献; 2）探测我们银河系中化学性质特殊的GCs的起源; 3）调查贫金属GCs之间令人困惑的质量-金属丰度关系; 4）评估dlrrs中GCs的水平分支形态。波恩大学Argelander天文学研究所（AlfA）的高水平和多样性的天文学研究将为这一项目提供一个极好的环境。

项目成果

New insights into the star formation histories of candidate intermediate-age early-type galaxies from K-band imaging of globular clusters

• DOI: 10.1111/j.1365-2966.2011.20115.x
• 发表时间: 2011-11
• 期刊: Monthly Notices of the Royal Astronomical Society
• 影响因子: 4.8
• 作者: I. Georgiev;P. Goudfrooij;Thomas Bonn;H Germany;Stsci;Baltimore.;Usa;P. U. C. D. Chile;Santiago;Chile.