Studies of Chemical Evolution

化学演化研究

• 批准号: 8913092
• 负责人: R.Earle Luck
• 金额: $ 17.2万
• 依托单位: Case Western Reserve University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1989
• 资助国家: 美国
• 起止时间: 1989-11-01 至 1993-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8913092&HistoricalAwards=false
• 关键词: Studies; Chemical; Evolution

A subject of central importance to astronomers is the chemical evolution of our and other galaxies. What were the elements, besides hydrogen and helium-4, out of which galaxies formed? How did the primordial abundances change during the intervening eons, due to stellar nucleosynthesis? Which types of stars contributed principally to this change? The Principal Investigator (PI) proposes to address these questions with regard to our Galaxy by continuing with his current NSF- supported research. He intends to use high-resolution stellar spectroscopy to obtain abundance data of carbon, oxygen, and nitrogen in young, metal-rich stars (i.e., non-variable supergiants, Cepheid stars, B-type stars on the main sequence, and red giants) and in metal-deficient stars. Metal-deficient stars specify the conditions at the time of the formation of the Galaxy, while the young stars specify current conditions. The observations for this project have been or are being carried out in collabo- ration with Lambert (Uni. of Texas), Bond (Space Telescope Science Inst.), and Rich (Columbia).

对天文学家来说，最重要的课题是我们的星系和其他星系的化学演化。除了氢和氦-4之外，星系是由哪些元素组成的？由于恒星的核合成，原始丰度在其间的亿万年中是如何变化的？哪些类型的恒星对这种变化起到了主要作用？首席研究员(PI)建议通过继续他目前由NSF支持的研究来解决关于我们银河系的这些问题。他打算使用高分辨率恒星光谱来获得年轻的、富金属的恒星(即不变的超巨星、造父变星、主序上的B型恒星和红巨星)和缺乏金属的恒星中碳、氧和氮的丰富数据。缺乏金属的恒星规定了银河系形成时的条件，而年轻恒星规定了目前的条件。该项目的观测已经或正在与兰伯特大学(UNI)合作进行。德克萨斯州)、邦德(太空望远镜科学研究所)和里奇(哥伦比亚)。