Line Shape for Collision Systems Important in Earth's, Planetary, and Exoplanet Atmospheres

红外线和太阳辐射被大气中的水和微量气体吸收，驱动着大气化学和气候。个别物种吸收辐射在独特的光谱带和窗口和数量不同的压力和温度为每个分子。为了准确计算大气吸收的能量，并利用遥感技术探测这些分子，需要精确的逐线光谱吸收参数，包括它们随环境参数的变化。本研究利用基本物理学原理构建了大气中主要气体的精确谱线形状参数，这些参数将用于大气辐射和遥感反演模型，以提高我们对大气化学的认识。本研究将建立一个统一的理论框架，以计算地球大气中重要气体的压力展宽半宽度和压力诱导谱线位移及其与速度和温度的关系。改进后的形式主义将超越目前的Voigt廓线近似，以加强遥感反演和逐线计算的辐射强迫的气候。该研究将开发新的Hartmann-Tran配置文件，该配置文件需要速度依赖的线形参数，这些参数将通过使用从头算和修改的复杂Robert-Bonamy代码计算的数千个振子跃迁进行估计。它将针对H2O，CO2，O3和CH 4在与N2，O2碰撞时的谱线展宽，以及在大气相关温度和压力下的自碰撞。具体来说，线耦合和混合的影响，半宽度将严格处理和校准使用现有的观测。除了推进美国社区的HITRAN数据库，重点研究将丰富遥感反演和痕量气体的辐射强迫，以推进大气化学和气候。

Infrared and solar radiation absorbed by atmospheric water and trace gases drives atmospheric chemistry and climate. Individual species absorb radiation in unique spectral bands and windows and the amounts vary with pressure and temperature for each molecule. In order to accurately compute the energy absorbed by our atmosphere and to use remote sensing to detect these molecules accurate line by line spectral absorption parameters including their variation with environmental parameters is needed. This research uses fundamental physics to construct accurate line shape parameters of key atmospheric species that will be used in atmospheric radiation and remote sensing retrieval models to advance our knowledge of atmospheric chemistry.This research will develop a unified theoretical framework to calculate pressure-broadened half-widths and pressure-induced line shifts, their velocity and temperature dependences for gases important in the Earth's atmosphere. The improved formalism will go beyond the current Voigt profile approximation to enhance remote sensing retrievals and line-by-line computations of radiative forcing of climate. The research will develop the new Hartmann-Tran profiles that require velocity dependent line shape parameters that will be estimated from thousands of ro-vibronic transitions that will be computed using ab initio and Modified Complex Robert-Bonamy codes. It will target H2O, CO2, O3 and CH4 line broadening in collision with N2, O2, and self-collisions at atmospherically relevant temperatures and pressures. Specifically, the effects of line coupling and mixing on half-widths will be rigorously treated and calibrated using available observations. In addition to advancing the U.S. community HITRAN database focused studies will enrich remote sensing retrievals and radiative forcing by trace gases to advance atmospheric chemistry and climate.