论文标题
质子撞击的水，甲烷和氨分子的多元电离的独立原子模型描述
Independent atom model description of multiple ionization of water, methane, and ammonia molecules by proton impact
论文作者
论文摘要
我们使用独立的原子模型研究了与水，甲烷和氨分子质子碰撞中的多个电离。对总（NET）捕获和电离横截面的先前工作进行了扩展，以明确处理多个电离通道。我们介绍了在独立原子模型方法中处理电荷状态相关过程的理论框架，该方法使用针对不同分子几何和方向引入的几何筛选。对目标分子进行比较，$ \ rm H_2O，CH_4，NH_3 $，重点是$ Q $ - 折 - 倍电子删除。生产的分子碎片的重合测量可用于估计该数量。对于水分子的模型计算，我们发现数据非常好，其中数据以$ q = 1-4 $存在。对于甲烷，我们观察到合理的协议，$ q = 1,2 $，对于氨，仅以$ q = 1 $，即实验数据在后一种情况下对直接多重电离通道的支持很少。
We study multiple ionization in proton collisions with water, methane, and ammonia molecules using an independent-atom model. Previous work on total (net) capture and ionization cross sections is extended to treat the multiple ionization channels explicitly. We present the theoretical framework to treat charge-state correlated processes within the independent-atom model approach which uses the geometric screening introduced for different molecular geometries and orientations. Comparison of results is made for the target molecules $\rm H_2O, CH_4, NH_3$ with an emphasis on $q$-fold electron removal. Coincident measurements of produced molecular fragments can be used to estimate this quantity. We find very good agreement for the model calculations for the water molecule, where data exist for $q=1-4$. For methane we observe reasonable agreement with $q=1,2$, and for ammonia only for $q=1$, i.e., the experimental data show little support for a direct multiple ionization channel in the latter case.
