氢分子和氮分子的精确动力学参数研究

The energy level structures of diatomic molecules have been studied extensively and well summarized. However, the investigations of the momentum transfer dependence behavior of the wave functions and physical properties of the ground and excited states of diatomic molecules are very few. The accurate dynamic parameters of the diatomic molecules including their Compton profiles, squared form factors and differential cross sections can provide the comprehensive information of the wave function distributions in the momentum space of the ground and excited states of diatomic molecules, which promotes the progress of the new theoretical models and calculational methods, as well as to deepen understanding or renew the corresponding physical concepts. In this project, we will measure Compton profiles, the vibration-resolved squared form factors, differential cross sections and generalized oscillator strengths of the valence-shell excitations of hydrogen and nitrogen with different experimental techniques such as Compton scattering, inelastic x-ray scattering and fast electron scattering. Then the momentum transfer dependence behavior of the dynamic parameters of ground and excited states of hydrogen and nitrogen can be elucidated from different viewpoints. This project will give the comprehensive information of the wave function distributions in the momentum space of the ground and excited states of hydrogen and nitrogen,

对双原子分子的能级结构特性，人们已经研究得较为透彻。但是双原子分子的另一特性，也即其波函数及相关物理量在动量空间中的行为，人们了解得还很少。研究双原子分子的精确动力学参数，包括其x射线散射的康普顿轮廓、非弹性x射线散射的形状因子平方、快电子碰撞的微分散射截面，可以全面揭示双原子分子基态和激发态波函数在动量空间中的分布信息，同时能够加深或更新人们对于有关概念的理解，并促进新的理论模型和计算方法的发展。本项目拟采用多种实验技术，包括康普顿散射技术、非弹性x射线散射技术和快电子散射技术，测量H2和N2分子的康普顿轮廓、振动分辨的价壳层激发态的形状因子平方、微分散射截面和广义振子强度，从不同的侧面研究并揭示H2和N2分子基态和价壳层激发态动力学参数的动量转移依赖特性。本项目工作的开展，将给出H2和N2分子完整的、从基态到价壳层激发态的波函数在动量空间中的分布信息。

应用康普顿散射方法、非弹性x射线散射方法、快电子能量损失谱方法，高分辨地测量了H2、N2、CO等原子分子基态和激发态的康普顿轮廓、形状因子平方、广义振子强度，从不同的侧面全面系统研究了H2、N2、CO等原子分子从基态到激发态的散射动力学参数，通过交叉检验不同实验方法所得结果，排除了可能存在的系统误差，给出了相应动力学参数的实验基准，揭示了这些原子分子从基态到激发态的电子结构信息。实验发现，对于弹性散射，x射线散射能够揭示分子的纯电子结构信息，而快电子散射则不能，这是源于电子散射中靶核的贡献和靶电子贡献的干涉效应。在研究过程中，发展并命名了dipole (γ, γ)方法，在实验方法发展方面取得较好成绩。