Theoretical Studies of Interstellar Matter

星际物质的理论研究

• 批准号: 8921939
• 负责人: Alexander Dalgarno
• 金额: $ 30万
• 依托单位: Harvard University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1990
• 资助国家: 美国
• 起止时间: 1990-03-15 至 1993-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8921939&HistoricalAwards=false
• 关键词: Theoretical; Studies; Interstellar; Matter

Dr. Dalgarno will continue research on the chemical processes in the interstellar medium. Quantum mechanical calculations will be carried out on a variety of atomic and molecular processes that are significant in astrophysical environments with particular attention to processes occurring in the interstellar medium and in the ejecta of supernova 1987A. Theoretical studies will be performed on the ionization structure, heating and cooling mechanisms and the molecular composition of supernovae, interstellar clouds, and the influence of ultraviolet photons and X-rays on the structure of molecular clouds in galaxies. The infrared response of molecular hydrogen to X-rays will be calculated. Although it is extremely tenuous, the interstellar medium (ISM) is the site of many complicated atomic and molecular reactions. Essentially all elements are present in varying quantities, and they are known to combine to form diverse molecules such as water, ammonia, alcohol, and even more complicated species. Also, larger particles of ice and dust are present. This complicated medium is then continually bombarded with various sources of energy including cosmic rays, X-rays, low and high energy photons, collisions between atoms and molecules, shock waves, various bulk movements of the ISM, and turbulent kinetic energy. This reactive "soup" quite expectedly emits photons from many electronic transitions and observing these gives data on the physical and chemical conditions in the vast space between the stars. However, because of the complications involved, interpretation of ISM observations is not straightforward and requires laboratory measurements and quantum mechanical calculations for their understanding. Dr. Dalgarno's highly regarded theoretical research is directed toward furthering our understanding of the constituents and activity in the ISM.

达尔加诺博士将继续研究化学过程， 星际介质 量子力学计算将是 在各种原子和分子过程中进行， 在天体物理环境中具有重要意义， 星际介质和喷出物中发生的过程 超新星1987A 理论研究将在 电离结构，加热和冷却机制， 超新星、星际云的分子组成， 紫外光子和X射线对 星系中的分子云 分子的红外响应 将计算氢到X射线的转化率。 虽然星际介质非常稀薄，但它是 许多复杂的原子和分子反应的场所。 基本上所有元素都以不同的量存在， 已知它们联合收割机形成不同的分子如水， 氨酒精还有更复杂的物质 此外，更大 存在冰和尘埃的颗粒。 这种复杂的媒介是 然后不断受到各种能源的轰击， 宇宙射线、X射线、低能量和高能量光子、碰撞 原子和分子，冲击波，各种各样的整体运动 以及湍流动能的影响。 这种反应性的"汤" quite quite quantum emits光子from many许多electronic电子transitions跃迁and 观察这些可以得到物理和化学条件的数据 在浩瀚的星空中 但因为 涉及并发症，ISM观察结果的解释不是 简单明了，需要实验室测量和量子 机械计算以供他们理解。 达尔加诺博士的 高度重视的理论研究是针对进一步 我们对ISM的组成和活动的理解。