RUI: Proto-Planetary Nebulae - High-Resolution Studies with Enlarged Sample

该计划的目标是通过确定原行星状星云的物理性质，更好地了解原行星状星云，即从渐近巨星分支到行星状星云阶段的演化恒星过渡过程中的物体。这些天体代表了恒星演化周期中一个重要但人们知之甚少的阶段。该项目正在扩大已确认的原行星状星云样本，对它们进行高分辨率光谱和空间观测，特别是利用氢分子发射来研究它们的特性。美国国家科学基金会支持的一项独特的、长达十年的关于这些物体脉动变化的研究的结果，这项研究正在继续和扩展，正在分析和准备出版。这里的计划包括以下内容：（1）对原行星状星云候选者的扩大样本进行分析，这些样本与迄今为止研究的大多数样本具有不同的特性； （2）高分辨率分子光谱，用于研究星周包膜的化学和动力学； (3) 原行星状星云高分辨率红外成像，直接研究尘埃的热发射； （4）中心恒星的高分辨率化学丰度研究，以研究核合成对渐近巨星分支的影响； (5) 分析和继续瓦尔帕莱索大学正在进行的独特的原行星状星云光变性研究。大量观测数据已经掌握。其他数据将通过国家天文台的望远镜和仪器获取。更广泛的影响：这项活动对理科学生的培训、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了非常积极的影响。每年有三名学生担任该项目的研究助理。 他们接受了使用现代天文设备的培训，教授如何进行观测和减少数据，并学习如何分析数据和准备传播结果。他们经历了研究项目的几乎所有阶段，并在会议上展示了他们的结果。积极寻求女性和少数族裔作为参与者，项目主任在让女学生参与其研究方面有着良好的记录。这个研究项目的兴奋点融入了通识教育天文学课程和实验室研究经验中使用的一些真实数据。该项目提供的天文学项目的持续活力增强了本科院校瓦尔帕莱索大学的研究基础设施。 该程序提供了更现代的 CCD 探测器和新的数据计算机

The goal of this program is to better understand proto-planetary nebulae, objects in transition as evolved stars from the asymptotic giant branch to the planetary nebula phase, by determining their physical properties. These objects represent an important but poorly understood phase in the evolutionary cycle of stars. The project is enlarging the sample of confirmed proto-planetary nebulae, to carry out high-resolution spectral and spatial observations of them, especially using molecular hydrogen emission, to investigate their properties. The results of a unique, decade-long NSF-supported study of pulsational variability in these objects, a study being continued and extended, are being analyzed and prepared for publication. The program here involves the following: (1) an analysis of an enlarged sample of proto-planetary nebulae candidates chosen with different properties from most of those studied thus far; (2) high-resolution spectroscopy of molecules to study the chemistry and dynamics of the circumstellar envelopes; (3) high-resolution infrared imaging of proto-planetary nebulae to study the dust directly from its thermal emission; (4) a high- resolution chemical abundance study of the central stars to investigate the effects of nucleosynthesis on the asymptotic giant branch; and (5) analysis and continuation of the unique light variability study of proto-planetary nebulae being carried out at Valparaiso University. A significant amount of the observational data is already in hand. Additional data will be acquired with telescopes and instruments at the national astronomical observatories.Broader Impacts: This activity has a very positive impact on the training of science students, the education of liberal arts students, and on the infrastructure for science at Valparaiso University. Three students each year serve as research assistants on the project. They are trained in the use of modern astronomical equipment, taught to carry out the observations and reduce the data, and learn how to analyze the data and prepare the results for dissemination. They experience almost all phases of a research program and present their results at conferences. Women and minorities are actively sought as participants, and the project director has a strong record of having women students participate in his research. The excitement of this research project is integrated into the general education astronomy classes and some of the real data used in laboratory research experience. The research infrastructure at Valparaiso University, an undergraduate institution, is enhanced by the continued vitality of the astronomy program that this project provides. The program provides a more modern CCD detector and new computers for data