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，对星系的形成和演化以及元素的形成都有影响。分子云是银河系恒星形成的地方，其结构和演化将由麦基博士进行研究。分子云被观察到是高度团块的，计算将决定团块之间介质的性质。分子云的早期演化过程将被计算出来，在这个过程中，大部分的原子气体变成了分子气体。我们将研究重力束缚团块中的压力分布。计算将追踪云内部形成的大质量恒星对云的破坏。激波塑造了漫射星际云的质谱，强大的流体力学和磁流体力学计算机代码将用于研究激波与云的相互作用。冲击波可以产生水脉波，这是大质量恒星形成的标志，这种情况发生的条件将被评估。星际介质中许多由恒星产生的重元素被锁在微小的尘埃颗粒中；这些颗粒在星际冲击中的溅射、汽化和破碎将被计算出来。