高能类氦重离子与单原子碰撞中炮弹离子K壳双电子变动过程研究

Colliding by high energy, highly charged ions are very strong perturbations to target atoms, and the reaction channels involving double K-shell electrons are ideal routes to the electron-electron correlation and the double electron QED effects in strong Coulomb fields. In our previous experiments, we found that fully stripped Xe ions at 52–197 MeV/u induce strong double K-shell ionization of Kr and Xe atoms, while Ni19+ ions at 185 MeV/u cannot. In order to deeply understand these kind of violent collisions, we have to continuously develop the relativistic coupled channel theory, which is started from the Dirac equations. We propose investigating the double K-shell electrons variation processes in the projectile frame in collisions between helium-like heavy ions and single atoms, in order to strictly compare with the theory at the present stage. This will dramatically reduce the system complexity, improve the experiment efficiency, and will produce much more precise benchmarks for theories.

高能高电荷态重离子与原子碰撞是对原子体系的极强扰动过程；其中K壳双电子参与的反应是研究强库仑场中电子-电子关联和双电子QED 效应的理想切入点。在前期实验我们中发现52–197 MeV/u的全裸Xe离子可以引起Kr和Xe原子显著双K壳电离，而185 MeV/u的Ni19+离子则不能。要深入理解此类剧烈碰撞，需要持续发展基于Dirac方程的相对论耦合道理论。为与现阶段理论进行更严格的对比，我们提出用类氦重离子轰击单个原子，在离子坐标系中研究炮弹离子的K壳双电子变动过程。这将大大降低系统复杂度，提高实验效率，并为理论发展提供更加精准的实验参考。

高能高电荷态重离子与原子碰撞中K壳双电子参与的反应是研究强库仑场中电子-电子关联和双电子QED 效应的理想切入点。利用重离子轰击单个原子，在离子坐标系中研究炮弹离子的K壳双电子变动过程，可以大大降低系统复杂度，并为理论发展提供更加精准的实验参考。依托兰州重离子加速器冷却储存环和气体内靶装置，我们利用百MeV/u能量的镍、氪等重离子分别轰击单个原子，通过测量K壳双空穴态离子退激发出的K X谱线，获得了百MeV/u能区镍、氪离子与氩、氪、氙等单原子碰撞中炮弹离子K壳双电子变动的实验数据。结合基于Dirac-Fock-Sturm轨道的相对论耦合道（RCC）、多组态Dirac-Fock理论及蒙特卡罗方法研究了不同扰动程度下炮弹离子的K壳双电子变动过程，证实强库伦强扰动下的内壳多电子变动过程的非微扰机制。