Galaxy formation and the chemistry of stars

我的研究主要是针对星系形成场景的观测测试。 通过确定从晕场星到球状星团，再到各种矮星系中的恒星的各种恒星群的化学特征，我们可以重建每个系统的化学演化，并将其与半解析模型和N体模拟对本星系群合并历史的预测进行比较。 在这次NSERC更新中，我概述了两个新的硕士项目，两个新的博士项目，以及一个需要PDF专业知识的项目，所有这些都在我的研究目标和合作范围内。 PDF项目涉及船底座矮星系的化学演化建模，我目前正在从其RGB恒星的高分辨率光谱计算详细的化学丰度比;这个职位将为UVic带来新的专业知识，同时也补充了现有的资源。 博士项目包括：（1）分析孤立矮不规则星系中各种恒星种群的金属丰度，运动学和年龄，特别是旧恒星种群与原星系碎片模型的比较，以及（2）详细分析外晕球状星团中的恒星，以确定外星系晕的均匀性和起源。 后一个项目将开始作为一个硕士项目。 另一个理学硕士项目包括对新的超微弱矮星系中的恒星进行详细的化学分析，这些星系可能是本星系群中金属含量最低的恒星。 本文概述了关于尘埃对贫金属恒星化学性质影响的另一个项目。 这些项目是UVic恒星化学新计划的一部分，该计划补充了恒星演化和星系形成方面现有的强大计划，以及恒星核合成方面新开发的计划。

My research is primarily directed at observational tests of galaxy formation scenarios. By determining the chemical signatures for various stellar populations from halo field stars, to globular clusters, to stars in a variety of dwarf galaxies, then we can reconstruct the chemical evolution of each system and compare that with predictions for the merger history of the Local Group from semi-analytic models and N-body simulations. In this NSERC renewal, I outline two new MSc projects, two new PhD projects, and a project that requires PDF expertise, all within my research goals and collaborations. The PDF project involves modeling of the chemical evolution of the Carina dwarf galaxy from the detailed chemical abundance ratios that I am currently calculating from high resolution spectra of its RGB stars; this position will bring new expertise to UVic while also complementing the existing resources. The PhD projects include (1) the analysis of the metallicity, kinematics, and ages of the various stellar populations in the isolated dwarf irregular galaxies, particularly of the old stellar populations to compare with models of protogalactic fragments, and (2) the detailed analysis of stars in outer halo globular clusters to determine the homogeneity and origins of the outer Galactic halo. This latter project would begin as an MSc project. The other MSc project includes the detailed chemical analysis of stars in the new ultra faint dwarf galaxies which may harbour the most metal-poor stars in the Local Group. An additional project on the effects of dust on the chemistry of metal-poor stars is outlined herein. These projects are part of the new program in stellar chemistry at UVic, which compliments the existing strong programs in stellar evolution and galaxy formation, as well as a newly developing program in stellar nucleosynthesis.