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Accurate Atomic Transition Probabilities in Aid of APOGEE and the Study of Galactic Chemical Evolution

准确的原子跃迁概率辅助 APOGEE 和银河化学演化研究

基本信息

批准号：
2206050
负责人：
Elizabeth Den Hartog
金额：
$ 36.94万
依托单位：
University of Wisconsin-Madison
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2022
资助国家：
美国
起止时间：
2022-09-01 至 2025-08-31
项目状态：
未结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=2206050&HistoricalAwards=false
关键词：
Accurate Atomic Transition Probabilities Aid

项目摘要

Spectroscopy of metal-poor stars – very old stars deficient in elements heavier than helium – is one of the most important means to study the origin of chemical elements in the Milky Way. This research project will primarily generate high quality laboratory measurements of infrared (IR) atomic spectra and transition probabilities that will enable the Apache Point Observatory Galactic Evolution Experiment (APOGEE) spectroscopic survey to accurately determine elemental abundances in metal-poor stars residing in the dusty bulge of the Milky Way. This will allow astronomers to better understand the sites and processes of nucleosynthesis and the chemical enrichment history of the Galaxy. Data generated in this project will also be useful for observations undertaken with the next generation of large IR telescopes. This project will provide opportunities for undergraduate students to be involved in advanced spectroscopic research, as well as opportunities for community engagement with local elementary school teachers and high school students.Using advanced experimental techniques, the research team of the Wisconsin Atomic Transition Probability program (WATP) will measure high resolution near IR spectra of lanthanide and Fe-group elements, and optical and ultraviolet (UV) spectra of key lanthanide elements. This will permit determination of accurate, absolute atomic transition probabilities. WATP personnel are collaborating with some of the leading experts in the study of metal-poor stars, and this project represents the beginning of a focused effort to measure transition data in the near IR wavelength range, specifically targeting several measurements in the H-band, in aid of the large APOGEE survey. The data generated by this project will improve the ability of APOGEE to a) determine the important parameter log(g), or stellar surface gravity, b) discriminate between predominantly r(apid)-process and predominantly s(low)-process n(eutron)-capture nucleosynthesis sites, and c) determine more reliable abundances of several Fe-group species. In addition to these near IR studies, this project will generate optical and UV measurements of important n-capture lanthanide elements. The methods of quantitative atomic spectroscopy developed and applied in this project are also expected to benefit other fields such as analytical chemistry.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

贫金属星的光谱是研究银河系化学元素起源的最重要的手段之一。贫金属星是非常古老的恒星，缺乏比氦重的元素。这项研究项目将主要产生高质量的红外(IR)原子光谱和跃迁概率的实验室测量结果，这将使阿帕奇点天文台星系演化实验(APOEE)光谱测量能够准确地确定居住在银河系尘埃凸起中的贫金属星的元素丰度。这将使天文学家更好地了解核合成的地点和过程以及银河系的化学富集史。该项目产生的数据也将对使用下一代大型红外望远镜进行的观测有用。该项目将为本科生提供参与高级光谱研究的机会，以及与当地小学教师和高中生进行社区互动的机会。威斯康星州原子跃迁概率计划(WATP)的研究团队将利用先进的实验技术，测量稀土元素和铁族元素的高分辨率近红外光谱，以及关键稀土元素的光学和紫外(UV)光谱。这将允许确定准确的、绝对的原子跃迁概率。WATP工作人员正在与一些研究贫金属星的主要专家合作，该项目代表着一项集中努力的开始，以测量近红外波长范围内的跃迁数据，特别是针对H波段的几项测量，以帮助进行大型远地点调查。该项目产生的数据将提高远地点以下方面的能力：a)确定重要参数LOG(G)或恒星表面重力，b)区分主要的r(Apid)过程和主要的S(低)过程n(中微子)俘获核合成点，以及c)确定几个铁族物种更可靠的丰度。除了这些近红外研究外，该项目还将对重要的n-俘获稀土元素进行光学和紫外测量。在这个项目中开发和应用的定量原子光谱分析方法也有望惠及其他领域，如分析化学。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。