Mars nightside electron impact process frequency empirical model

With the aim of improving global simulations of the Martian ionosphere, we present an empirical model of 137 electron impact processes---including ionization, dissociation, and excitation---on the nightside of Mars, based on MAVEN in situ data collected between 2014 and December 2019., , , # Mars nightside electron impact process frequency empirical model [https://doi.org/10.5061/dryad.pc866t1wm](https://doi.org/10.5061/dryad.pc866t1wm) The frequencies of 137 different electron impact processes in the Martian nightside ionosphere---including ionization, dissociation, and excitation---are modeled separately. Species considered are: CO_2, N_2, Ar, O, and CO. Model parameters are: magnetic field strength, magnetic elevation angle, magnetic topology, solar wind pressure, and altitude. Characterization of the degradation of electron precipitation as the altitude decreases and atmospheric density increases has been calculated using a weighted number density of neutrals as its basis, and used to adjust frequencies. This calculation is explained in more detail in a manuscript currently in prep. Magnetic topology types are described in Xu et al. 2019, though here \"night closed\" and \"night void\" topologies are combined. Topology type codes are: 0-undefined, 1-day closed, 2-cross ...,为提升全球火星电离层模拟精度，本研究基于2014年至2019年12月期间获取的火星大气与挥发物演化探测器（MAVEN）原位探测数据，构建了火星夜间侧137种电子碰撞过程的经验模型，涵盖电离、解离与激发三类过程。 # 火星夜间侧电子碰撞过程频率经验模型 https://doi.org/10.5061/dryad.pc866t1wm 本研究对火星夜间侧电离层内137种不同电子碰撞过程的发生频率分别进行建模，涵盖电离、解离与激发三类过程。研究所涉及的大气组分包括二氧化碳（CO₂）、氮气（N₂）、氩气（Ar）、氧原子（O）与一氧化碳（CO）。模型输入参数包括磁场强度、磁仰角、磁拓扑结构、太阳风压强以及海拔高度。研究以加权中性粒子数密度为基准，计算了随海拔降低、大气密度升高时电子沉降的衰减特性，并利用该结果修正碰撞过程的发生频率。相关计算的详细说明将在待出版的手稿中予以阐述。磁拓扑类型的定义可参考Xu等人2019年的研究，但本研究中将"夜间闭合"与"夜间虚空"两类拓扑结构进行了合并。拓扑类型编码规则为：0表示未定义，1表示日间闭合，2表示跨极……