基于类betatron振荡的高亮飞秒伽马射线源研究

基于betatron振荡的高亮飞秒伽马射线源研究是激光等离子体领域的前沿研究热点。本项目首先针对相对论激光条件下的激光等离子体相互作用动力学问题展开理论分析和大规模数值模拟研究，在考虑辐射阻尼效应和辐射的极化特性的基础上，分析激光固体微型靶相互作用中的类betatron振荡现象，探索产生类batatron共振的物理条件并建立合理有效的物理模型，揭示电子共振的内在机理，阐明高亮飞秒伽马射线的激励机制。开展圆极化激光驱动电子空泡加速的理论和模拟研究，获得电子类betatron振荡的动力学特征和辐射特性参数，通过优化激光和等离子体参数实现可调谐飞秒伽马射线源的产生，为将来开展相关辐射源实验提供技术方案和理论参考。

Betatron resonance based bright femtosecond gamma ray emission is one of the most extensively discussed topics in the field of laser-plasma community. Taking account of the radiation damping effect and the polarization of the radiation in the particle-in-cell simulation code, we first study the interaction of an intense laser pulse with plasma targets, and analyse the betatronlike oscillation of electrons during the laser micro-target interaction. By creating a reasonable model,we discuss the conditions for the resonance and reveal the underlying mechanism of the gamma ray emission. Then, we study the electron bubble acceleration driven by a circularly polarized laser pulse and analyse the betatronlike oscillation of electrons in the bubble to obtain the features of the radiation. By optimizing the laser and plasma parameters, we acheive femtosecond tunable gamma ray emission. The research may provide a reference for future experiments with possible schemes and models.