RUI: Variability - A Key Probe of the Properties and Evolution of Post-AGB Stars and Proto-Planetary Nebulae

RUI：变异性——AGB后恒星和原行星状星云的性质和演化的关键探测

• 批准号: 1009974
• 负责人: Bruce Hrivnak
• 金额: $ 22.61万
• 依托单位: Valparaiso University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-09-01 至 2016-02-29
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1009974&HistoricalAwards=false
• 关键词: RUI; Variability; Key; Probe; Properties

This project will determine the basic physical properties of proto-planetary nebulae (PPNe).These are objects in transition from the evolved red giants to the planetary nebula phase in the evolution of solar- and intermediate-mass stars. This new study will enlarge current samples to include oxygen-rich stars. It will include some PPNe in the nearby Large and Small Magellanic Cloud galaxies. Combining the variability results with color and radial velocity data will permit a direct determination of the stellar radius and luminosity. It is also anticipated that the long time-series data set (up to 20 years in some cases) obtained by the end of this project will reveal, for the first time, real-time evolution in pulsation periods, an additional observational constraint on the evolutionary models. Binarity and its effect on the shaping of the nebulae will be investigated through precise radial velocity observations.The research project involves both national and international collaborations. The activity is also expected to have a positive impact on the training of science students, the education of liberal arts students, and on the infrastructure for science at Valparaiso University. The methods and results from this research project will also be integrated into the general education astronomy classes and some of the observational data will be used in laboratory research experiences. Dr. Hrivnak and student research assistants will carry out a program of public open house viewing at the Valparaiso Observatory and community outreach, and make regular community and professional presentations on astronomy.

该项目将确定原行星状星云(PPNe)的基本物理性质。这些天体在太阳和中等质量恒星的演化过程中处于从红巨星演化到行星状星云阶段的过渡阶段。这项新的研究将扩大目前的样本，将富氧恒星包括在内。它将包括附近大小麦哲伦星云星系中的一些PPNe。将可变性结果与颜色和径向速度数据相结合，将可以直接确定恒星的半径和光度。还预计，到本项目结束时获得的长时间序列数据集(在某些情况下长达20年)将首次揭示脉动期的实时演变，这是对演变模型的另一个观测限制。将通过精确的径向速度观测来研究双星及其对星云形成的影响。这项研究项目涉及国内和国际合作。预计该活动还将对理科学生的培训、文科学生的教育以及瓦尔帕莱索大学的科学基础设施产生积极影响。这一研究项目的方法和结果也将融入普通教育天文学课程，一些观测数据将用于实验室研究经验。赫里夫纳克博士和学生研究助理将在瓦尔帕莱索天文台开展公众开放参观计划和社区推广活动，并定期在社区和专业人士中介绍天文学。