Probing Element Abundance Changes in Galactic Stars

我们银河系中恒星的组成为它的诞生和恒星形成的历史提供了重要的线索。恒星在内部制造元素。恒星死亡时，会将新元素释放到银河系的气体中。研究人员试图利用从恒星光谱中得出的恒星丰度，来了解元素的积累是如何导致今天复杂的元素周期表的。调查人员有三个目标。他们的第一个目标是提高化学成分分析的质量。他们将获得用于光谱分析的基本实验室数据。其次，它们将显著增加重要恒星群中被研究的恒星数量。通过这种方法，他们将研究银河系中不同恒星群的成员。第三，他们将为研究界和教育界提供服务。他们将向所有人免费提供新的实验室数据和丰富的分析软件。他们还将与德克萨斯州的一组科学教育者合作，将天文学研究与他们的教学工作联系起来。研究人员将提供非常精确的铁族元素丰度的测量，在许多金属贫乏的恒星在我们的银河系晕。他们将从大约20个银河系疏散星团的大样本中获得碳、氮、氧和锂的丰度，以及碳同位素比率。这项工作将独特地利用新获得的高分辨率光谱，涵盖光学和红外光谱域的广泛区域。他们将通过将光谱与盖亚天文测量卫星提供的运动学数据相结合来搜索银河系中的恒星流。他们还将利用星团中温暖的红巨星的新红外光谱和银河系盘的一般领域来探索这个问题。研究人员将继续发布实验室原子和分子光谱线数据的主要更新，并改进我们公开可用的光谱分析代码。调查人员将继续他们长期以来的努力，以提高德克萨斯州的科学教育质量。他们将与一群积极性很高的中学科学教育者一起工作。他们就最新的天文学研究发表演讲，并让教师参与可以带回课堂使用的项目。他们还将为教师提供参与望远镜使用的机会，在麦克唐纳天文台举办讲习班，并参加美国天文学会的会议。

The compositions of stars in our Milky Way Galaxy hold vital clues to its birth and history of forming stars. Stars make elements in their interiors. At their deaths, stars return the new elements into the gas of the Galaxy. The investigators seek to use abundances of stars, derived from their spectra, to understand how the buildup of elements led to the complex Periodic Table of today. The investigators have three goals. Their first goal is improving the quality of chemical composition analyses. They will obtain basic laboratory data that go into the spectrum analyses. Second, they will significantly augment the number of stars studied in important groups of stars. Through this they will study members of various Galactic star populations. Thirdly, they will provide service to the research and educational communities. They will make the new lab data, and abundance analysis software freely available to all. They will also work with a group of Texas science educators to link astronomical research with their teaching efforts.The investigators will provide very accurate measurements of iron-group element abundances in many metal-poor stars of the halo of our Galaxy. They will derive abundances of carbon, nitrogen, oxygen, and lithium, as well as carbon isotopic ratios in large samples of about 20 open clusters of the Galactic disk. This work will uniquely take advantage of newly-acquired high resolution spectra covering broad regions of both optical and infrared spectral domains. They will search for star streams in the Galaxy by mating optical spectra with kinematics to be provided by the Gaia astrometric satellite. They will also explore this issue with new infrared spectra of warm red giant stars in clusters and in the general field of the Galactic disk. The investigators will continue to release major updates of lab atomic and molecular spectral line data, and to improve our publicly-available spectrum analysis codes.The investigators will continue their long-standing effort to improve the quality of science education in the state of Texas. They will work with a highly-motivated group of secondary science educators. They give talks on the latest astronomical research, and to engage teachers in projects that can be carried back to use in their classrooms. They will also provide opportunities for teachers to participate in telescope usage, to have workshops at McDonald Observatory, and to attend meetings of the American Astronomical Society.