The Physical and Chemical Properties of Circumstellar Matter

星周物质的物理和化学性质

• 批准号: 9314408
• 负责人: Patrick Huggins
• 金额: $ 10.83万
• 依托单位: New York University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1994
• 资助国家: 美国
• 起止时间: 1994-06-15 至 1998-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9314408&HistoricalAwards=false
• 关键词: Physical; Chemical; Properties; Circumstellar; Matter

9314408 Huggins Many luminous red giant stars eject significant amounts of material from their outer layers. The star then evolves rapidly into a white dwarf while the matter is seen for a time as a planetary nebula. It is now known that the star and the visible nebula are surrounded by a large shell of neutral gas. The properties and evolution of these shells will be studied by observing their molecular emission at millimeter and sub-millimeter wavelengths. This information will be used to develop a description of the formation and evolution of the nebulae. These studies should substantially improve our understanding of this important but little understood phase of stellar evolution. ***

许多明亮的红巨星从外层喷射出大量的物质。这颗恒星随后迅速演变成一颗白矮星，而这一物质在一段时间内被视为行星状星云。现在我们知道，恒星和可见的星云被一个巨大的中性气体壳层包围着。通过观察它们在毫米波和亚毫米波波长下的分子发射来研究这些壳的性质和演化。这些信息将用于描述星云的形成和演化。这些研究将大大提高我们对这一重要但鲜为人知的恒星演化阶段的理解。＊＊＊