Novel phenomena and methods related to dielectronic capture and dielectronic recombination are studied for non-local thermodynamic equilibrium (LTE) plasmas and for applications to non-LTE ionization balance. It is demonstrated that multichannel autoionization and radiative decay strongly suppress higher-order contributions to the total dielectronic recombination rates, which are overestimated by standard approaches by orders of magnitude. Excited-state coupling of dielectronic capture is shown to be much more important than ground-state contributions, and electron collisional excitation is also identified as a mechanism driving effective dielectronic recombination. A theoretical description of the effect of angular-momentum-changing collisions on dielectronic recombination is developed from an atomic kinetic point of view and is visualized with a simple analytical model. The perturbation of the autoionizing states due to electric fields is discussed with respect to ionization potential depression and perturbation of symmetry properties of autoionization matrix elements. The first steps in the development of statistical methods are presented and are realized in the framework of a local plasma frequency approach. Finally, the impact of collisional–radiative processes and atomic population kinetics on dielectronic recombination is critically discussed, and simple analytical formulas are presented.

中文翻译：

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非 LTE 等离子体中的双电子复合

针对非局域热力学平衡 (LTE) 等离子体和非 LTE 电离平衡的应用，研究了与双电子捕获和双电子复合相关的新现象和方法。结果表明，多通道自电离和辐射衰减强烈抑制了对总双电子复合率的高阶贡献，而标准方法将其高估了几个数量级。双电子捕获的激发态耦合被证明比基态贡献重要得多，并且电子碰撞激发也被确定为驱动有效双电子复合的机制。角动量变化碰撞对双电子复合的影响的理论描述是从原子动力学的角度发展起来的，并用一个简单的分析模型进行了可视化。讨论了由于电场引起的自电离态的扰动，这涉及电离电位降低和自电离基体元素的对称性扰动。介绍了统计方法发展的第一步，并在局部等离子体频率方法的框架内实现。最后，批判性地讨论了碰撞辐射过程和原子群动力学对双电子复合的影响，并提出了简单的分析公式。讨论了由于电场引起的自电离态的扰动，这涉及电离电位降低和自电离基体元素的对称性扰动。介绍了统计方法发展的第一步，并在局部等离子体频率方法的框架内实现。最后，批判性地讨论了碰撞辐射过程和原子群动力学对双电子复合的影响，并提出了简单的分析公式。讨论了由于电场引起的自电离态的扰动，这涉及电离电位降低和自电离基体元素的对称性扰动。介绍了统计方法发展的第一步，并在局部等离子体频率方法的框架内实现。最后，批判性地讨论了碰撞辐射过程和原子群动力学对双电子复合的影响，并提出了简单的分析公式。