Theoretical Studies in Interstellar Astrophysics

星际天体物理学理论研究

• 批准号: 9221289
• 负责人: Christopher McKee
• 金额: $ 30.67万
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-03-01 至 1996-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9221289&HistoricalAwards=false
• 关键词: Theoretical; Studies; Interstellar; Astrophysics

The process by which interstellar gas gathers into stars is a fundamental problem in astrophysics, with implications for the formation and evolution of galaxies and the formation of the elements. The structure and evolution of molecular clouds, the sites of Galactic star formation, will be investigated by Dr. McKee. Molecular clouds are observed to be highly clumped, and calculations will determine the nature of the medium between the clumps. The early evolution of a molecular cloud, in which a largely atomic gas becomes molecular, will be calculated. The distribution of pressure in gravitationally bound clumps will be investigated. Calculations will trace the destruction of the clouds by the massive stars that form within them. Shock waves shape the mass spectrum of diffuse interstellar clouds, and powerful hydrodynamic and magnetohydrodynamic computer codes will be used to study the interaction of shocks with clouds. Shock waves can produce water masers, which are signposts of massive star formation, and the conditions under which this can occur will be evaluated. Many of the heavy elements of the interstellar medium, which are produced by stars, are locked up in tiny dust grains; the sputtering, vaporization, and shattering of these grains in interstellar shocks will be calculated.

星际气体聚集成恒星的过程是天体物理学中的一个基本问题，它与星系的形成和演化以及元素的形成有关。麦基博士将研究分子云的结构和演化，也就是银河系恒星形成的地点。分子云被观察到是高度聚集的，计算将确定这些聚集之间的介质的性质。将计算分子云的早期演化，在分子云中，主要是原子气体变成分子。我们将研究重力约束团块中的压力分布。计算将追踪云层中形成的大质量恒星对云层的破坏。冲击波塑造了星际扩散云的质量谱，强大的流体力学和磁流体计算机代码将被用来研究激波与云的相互作用。冲击波可以产生水脉泽，这是大质量恒星形成的标志，我们将对发生这种情况的条件进行评估。由恒星产生的星际介质中的许多重元素被锁在微小的尘埃颗粒中；这些颗粒在星际冲击波中的溅射、汽化和破碎将被计算出来。