Laboratory Studies of O(1D) Processes Important in the Upper Atmosphere

研究人员将对单重态D态氧原子[O(1D)]的大气重要过程进行一系列实验。首先，他们将测量在300-1000K范围内处于三D态的氧原子碰撞去除O(1D)的速率系数[O(3D)]及其与温度的关系。最近的实验室研究表明，在200-300公里的高度，氧原子的驰豫是控制630 nm红线发射强度的最重要的过程。这项研究将产生第一组在相关高温下的实验室测量结果。研究人员还将调查其他反应速率对温度的依赖关系，这些反应速率对于了解大气中的氧排放非常重要。这些实验室实验对于改善目前对电离层红线发射的不完全了解、能够更好地模拟和量化分子氧大气带发射以及阐明氧原子在120-400公里高度范围内的能量转移的作用至关重要。此外，知道O(1D)被O(3P)碰撞去除的速率系数可以正确地解释和分析O(1D)的排放。这些结果将有助于正确解释和量化630纳米红线发射，从而提高电离层加热实验的科学性。要测量的速率系数与平静和扰动的大气条件都有关。这项工作还应有助于增进对卫星阻力的理解和对非相干散射雷达测量结果的解释。高层大气中的能量平衡是将地球作为一个系统建模的关键。将基础化学和物理应用于在基本水平上研究碰撞能量传递过程，对于理解激光器，特别是高功率化学激光器的运行也是至关重要的。最后，这项研究将有助于博士后研究员和暑期本科生的培训、指导和研究经验。

The investigators will conduct a series of experiments on atmospherically important processes involving oxygen atoms in the singlet D state [O(1D)]. First, they will measure the rate coefficient for the collisional removal of O(1D) by oxygen atoms in the triple D state [O(3D)] and its temperature dependence in the range 300 to 1000 K. Recent laboratory studies at room temperature have indicated that relaxation by oxygen atoms is the most significant process controlling the intensity of the 630 nm red line emission at altitudes 200-300 km. The study will yield the first set of laboratory measurements at the relevant high temperatures. The investigators will also investigate the temperature dependence of other reaction rates important for understanding atmospheric oxygen emissions. These laboratory experiments are essential for improving the currently incomplete understanding of ionospheric red-line emission, allowing for better modeling and quantification of molecular oxygen Atmospheric Band emissions, and elucidating the role of oxygen atom energy transfer in the altitude range 120-400 km. Also, knowledge of the rate coefficient for the collisional removal of O(1D) by O(3P) allows the correct interpretation and analysis of the O(1D) emissions. These results will enhance the scientific return of ionospheric heating experiments by enabling a correct interpretation and quantification of the 630-nm red line emission. The rate coefficients to be measured are relevant to both calm and perturbed atmospheric conditions. This work should also help improve understanding of satellite drag and the interpretation of results from incoherent scatter radar measurements. Energy balance in the upper atmosphere is key to modeling the Earth as a system. Application of basic chemistry and physics to the study of collisional energy transfer processes on a fundamental level is also critical for understanding the operation of lasers, especially high-power chemical lasers. Finally, the study will contribute to training, mentoring, and research experiences of postdoctoral fellows and summer undergraduate students.