高电荷态离子在等离子体中的双电子复合过程研究

高电荷态离子与等离子体作用中的电荷交换过程是聚变物理和天体物理领域涉及的关键微观作用过程，同时也是强流重离子加速器新型等离子体剥离技术的核心研究内容。由于等离子体中存在大量的自由电子,高电荷态离子与自由电子的双电子复合过程将会扮演重要的角色，相关物理建模和参数可靠性亟待实验检验。本项目将基于HIRFL上的离子束与等离子体相互作用实验平台，建立等离子体环境中双电子复合过程研究的实验新方法，1）首次通过精细调节离子束能量，观测出射离子电荷态分布及X射线强度两个重要特征信息，研究高电荷态离子在等离子体中的双电子复合共振条件及其反应速率；2）通过改变等离子体密度，精确调节离子在等离子体中的作用长度，观测和研究共振区域附近离子束在等离子体中的电荷态演化及其平衡过程。项目组成员及其研究团队前期实验和理论研究基础良好，经验丰富，有望率先实现等离子体环境中的DR实验观测并取得具有较高创新性的研究成果。

The charge exchange between Highly Charged Ions (HCIs) with plasma is not only the most popular process happening in fusion plasma and astrophysical plasma, but also is the focus for the plasma stripper development in heavy ion accelerator. Due to the large amount of free electrons in plasma, the dielectric combination (DR) process between the HCIs with free electron probably play the dominant role for the charge exchange. However, The precise mechanism is still not clarified, and the current theory and data library is in highly demand to be benchmarked. In this project, based on the for ion-plasma interaction research platform at HIRFL, we will build a novel experimental method for DR research on one hand, and on the other hand, obtain the DR resonance condition information and rate coefficient. The DR interaction environment in plasma is constructed through finely adjusting the projectile velocity. The analysis is based on the measurement of the X ray emission during the beam-plasma interaction as well as the charge state distribution passing through the plasma. In addition, the measurement for a series of plasma density will also be done to clarify the charge state evolution and the equilibration process of HCIs in plasma. in the related field, our team has solid foundation in both experimental research and theoretical calculation, and is expected to realize the DR process study directly in plasma environment for the first time and get good achievement at the end.