CAREER: Investigations of the Formation and Evolution of Stars in Young Embedded Clusters

职业：研究年轻嵌入式星团中恒星的形成和演化

• 批准号: 9733367
• 负责人: Elizabeth Lada
• 金额: $ 50万
• 依托单位: University of Florida
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-06-01 至 2004-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9733367&HistoricalAwards=false
• 关键词: CAREER; Investigations; Formation; Evolution; Stars

9733367 Lada The recent results from near-infrared wavelength imaging surveys have of stars have suggested that most stars in our Galaxy form in the environments of dense, embedded stellar clusters. The extent to which these new results should alter our current understanding of star formation physics is unclear. However, one would expect to find fundamental differences in the formation and early evolution of young stars in such dense regions as compared to more isolated regions. Therefore, establishing the properties of young stars in embedded clusters is essential to understanding the process of star formation and early stellar evolution and to estimate the overall likelihood of the existence of planetary systems in our Galaxy. An extensive and systematic broad-band infrared and millimeter wavelength study of 11 young embedded, or partially embedded, stellar clusters will be conducted. The stellar clusters range in age from 1 to 70 million years, and span a range of environment from gaseous hydrogen regions to reflection nebulae. The main goals of the research are: 1) to construct and compare the near-infrared wavelength luminosity functions and Hertzsprung-Russell diagrams for each cluster and to investigate the shape and universality of the stellar initial mass function (IMF) and 2) to determine and compare the frequency and mass distributions of circumstellar disks in each cluster. In addition to providing a rich data base for investigations of the star forming histories of young clusters, the observations will provide, for the first time, a complete and statistically significant census of circumstellar/proto-planetary disk sources in cluster environments. The comparison of the results of the analysis of the data for the stellar clusters with different ages will allow one to estimate the relative timescale for the disk phase of evolution within dense stellar environments. The duration of the disk phase is of particular importance, for it sets the time scale for planet format ion. The results can be compared to existing studies of young stars forming in relative isolation This will be done in order to determine the differences in the formation and evolution of stars and their disks in differing astrophysical environments. An integral part of this project is to carry out an educational and outreach plan that encourages, teaches, and mentors high school, college undergraduate and graduate students towards careers in the physical sciences. The plan also emphasizes a science outreach program directed toward college level undergraduates, the general public and young children. Specifically, it is planned to: 1) Develop non-traditional teaching methods via the use of computers for the introductory level astronomy undergraduate course at the University of Florida; 2) Develop a new course on the origins of the solar system, stars, and life. This course will integrate the results from recent research projects into the course material. The course will be developed for both an undergraduate and graduate level. 3) A journal club on star formation and related topics will be organized; 4) Students will be involved at all levels in the research activities; 5) A women's career day symposium will be organized for the purpose of encouraging women high school students to consider careers in the physical sciences. 6) Two regular public lecture series will be organized, one for adults and one for children, on astronomical topics to encourage an interest and appreciation of astronomy and science in general among the public at all age levels. ***

小行星9733367 最近对恒星进行的近红外波长成像调查的结果表明，我们银河系中的大多数恒星都是在密集的嵌入式星团环境中形成的。 这些新结果将在多大程度上改变我们目前对星星形成物理学的理解还不清楚。 然而，人们会期望在这样密集的区域中发现年轻恒星形成和早期演化的根本差异，而不是更孤立的区域。 因此，确定嵌入星团中年轻恒星的性质对于理解星星形成和早期恒星演化的过程以及估计银河系中行星系统存在的总体可能性至关重要。 将对11个年轻的嵌入式或部分嵌入式星团进行广泛和系统的宽带红外和毫米波长研究。 这些星团的年龄从100万年到7000万年不等，并跨越了从气态氢区域到反射星云的一系列环境。 研究的主要目的是：1）构造和比较每个星团的近红外波长光度函数和Hertzsprung-Russell图，研究恒星初始质量函数（IMF）的形状和普适性; 2）确定和比较每个星团中星周盘的频率和质量分布。 除了为研究年轻星团的星星形成历史提供丰富的数据库外，这些观测还将首次对星团环境中的星周/原行星盘源进行全面和具有统计意义的普查。 不同年龄的星团的数据分析结果的比较，将允许一个估计的相对时间尺度的磁盘阶段的致密恒星环境中的演变。 盘相的持续时间是特别重要的，因为它为行星格式设定了时间尺度。 结果可以与现有的年轻恒星形成的研究相对孤立，这将是为了确定在不同的天体物理环境中的恒星及其盘的形成和演化的差异。 该项目的一个组成部分是开展教育和推广计划，鼓励，教导和指导高中，大学本科生和研究生从事物理科学职业。 该计划还强调了针对大学本科生、公众和幼儿的科学推广计划。 具体而言，计划（1）在佛罗里达大学的天文学本科入门课程中，开发利用计算机的非传统教学方法;（2）开发关于太阳系、恒星和生命起源的新课程。 本课程将把最近的研究项目的结果整合到课程材料中。 该课程将为本科生和研究生水平开发。 3)将组织一个关于星星形成和相关专题的期刊俱乐部; 4）学生将参与各级研究活动; 5）将组织一次妇女职业日专题讨论会，以鼓励女高中生考虑从事物理科学职业。 6)天文台将定期举办两场公开讲座系列，分别为成人及儿童举办，以天文学为题，鼓励不同年龄的公众对天文学及科学的兴趣及欣赏。 ***