Laboratory Studies of Oxygen Atom Recombination in Nitrogen at Mesospheric Temperatures

中层温度下氮中氧原子复合的实验室研究

• 批准号: 1441896
• 负责人: Konstantinos Kalogerakis
• 金额: $ 39.79万
• 依托单位: SRI International
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-07-01 至 2018-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1441896&HistoricalAwards=false
• 关键词: Laboratory; Studies; Oxygen; Atom; Recombination

This award supports laboratory experiments to study the kinetics of the process of oxygen atom recombination in a molecular nitrogen environment and the pathways that lead to excited states of molecular oxygen (O2) at temperatures relevant to the Earth's mesosphere. The project will supply basic physical measurements needed to interpret and model important processes in the upper atmosphere, such as O2 airglow and atmospheric dynamics. In addition to observational and theoretical studies of Aeronomy, this work could benefit research on planetary atmospheres. The project will contribute to the training and research experience of one or more postdoctoral fellows and undergraduate students. The role of collisional relaxation, the temperature-dependent recombination rate coefficient, the dominant energy flow pathways, and the resulting O2 excited state yields will be studied. These measurements are needed for a quantitative understanding and reliable modeling of the atmosphere and its airglow emissions. Knowledge of the details relevant to the production of excited O2 is critical input for the study and modeling of atmospheric composition, energy transfer, airglow, and transport dynamics. The experimental methodology involves the photoinitiation of O-atom recombination in a suitable bath gas by an ultraviolet radiation pulse from an excimer laser. Fluorescence and resonance-enhanced multiphoton ionization (REMPI) techniques are used to monitor the decay of the O-atom population and detect excited O2 molecules, thus providing insight into the relevant removal rate coefficients, energy flow pathways, and yields of the excited O2 states produced following recombination.

该奖项支持实验室实验，以研究氧原子在分子氮环境中重组过程的动力学，以及在与地球中间层相关的温度下导致分子氧（O2）激发态的途径。该项目将提供解释和模拟高层大气重要过程所需的基本物理测量，如O2气辉和大气动力学。除了高层大气物理学的观测和理论研究外，这项工作还有助于行星大气的研究。该项目将有助于一个或多个博士后研究员和本科生的培训和研究经验。碰撞弛豫的作用，温度依赖的复合速率系数，占主导地位的能量流动途径，以及由此产生的O2激发态产量将进行研究。这些测量是定量了解和可靠的大气及其气辉排放建模所必需的。知识的细节相关的生产激发O2的大气成分，能量传递，气辉和运输动力学的研究和建模是关键的输入。实验方法涉及光引发的O-原子复合在一个合适的浴气体由紫外辐射脉冲从准分子激光器。荧光和共振增强多光子电离（REMPI）技术被用来监测衰减的O-原子人口和检测激发O2分子，从而提供洞察相关的去除率系数，能量流动的途径，并产生以下重组的激发O2状态的产量。