Circumstellar Matter: Neutral Envelopes and Planetary Nebula Formation

星周物质：中性包层和行星状星云的形成

• 批准号: 0307277
• 负责人: Patrick Huggins
• 金额: $ 18万
• 依托单位: New York University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-07-01 至 2007-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0307277&HistoricalAwards=false
• 关键词: Circumstellar; Matter; Neutral; Envelopes; Planetary

AST 0307277PI HugginsThis is a project studying the matter ejected during the red giant expansion phase of stars as they transition into their final shrunken white dwarf forms, the crucial stage of stellar evolution that terminates the normal lives of all low and intermediate mass stars. The mass ejected by the stars forms an expanding circumstellar envelope of neutral gas and dust that develops into a planetary nebula. Observations are being used to address key aspects of this evolutionary sequence, such as the ways in which stars lose mass toward these end stages of their lives, to help identify the mechanisms governing the mass-loss process, how the complex symmetries of planetary nebulae are imprinted on their neutral circumstellar envelopes by high velocity bipolar jets, and how the neutral envelopes of evolved planetary nebulae fragment into arrays of numerous cometary globules. Basic gas dynamical models are being tested in the course of this work.Broader impacts: The broader impacts of the proposed work have a strong educational focus. They include the direct training of students in research and the synergistic professional development of the principle investigator which includes the mentoring of students, contributing to the training of K-12 science teachers, and the development of new facilities and curricular materials for the teaching of astronomy. This program also fosters international cooperation, and the results will be widely disseminated within and beyond the discipline.

AST 0307277 PI Huggins这是一个研究恒星在红巨星膨胀阶段喷射出的物质的项目，当它们过渡到最终缩小的白色矮星形式时，恒星演化的关键阶段终止了所有低质量和中等质量恒星的正常生命。恒星喷射出的物质形成了一个不断膨胀的中性气体和尘埃的星周包层，并发展成行星状星云。观测被用来解决这一演化序列的关键方面，例如恒星在其生命的最后阶段失去质量的方式，以帮助确定控制质量损失过程的机制，行星状星云的复杂对称性如何被高速双极喷流印在其中性的星周封套上，以及行星状星云的中性包层是如何分裂成无数彗星状球状物的。更广泛的影响：拟议工作的更广泛的影响具有很强的教育重点。它们包括学生在研究和主要研究者的协同专业发展的直接培训，其中包括学生的辅导，促进K-12科学教师的培训，并为天文学教学开发新的设施和教材。该计划还促进了国际合作，其结果将在学科内外广泛传播。