A novel approach for positron injection and acceleration in the laser driven plasma wakefield is proposed. One ring-shaped beam and one coaxially propagating Gaussian beam drive wakefields in a preformed plasma volume filled with both electrons and positrons. The laser’s ponderomotive force as well as the charge separation force in the front bucket of the first bubble are utilized to provide the transverse momenta of injected positrons and those positrons can be trapped by the focusing field and then accelerated by the wakefield. Theoretical analysis of the process is presented and verified by particle-in-cell simulations. The simulations show that relatively high-charge, quasimonoenergetic positron beams can be obtained.

中文翻译：

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激光-等离子气泡状态下正电子的新注入和加速方案

提出了一种在激光驱动的等离子体尾波场中进行正电子注入和加速的新方法。一个环形光束和一个同轴传播的高斯光束在充满电子和正电子的预先形成的等离子体体积中驱动尾波场。利用激光的质动力以及在第一个气泡的前桶中的电荷分离力来提供注入的正电子的横向动量，这些正电子可以被聚焦场捕获，然后被尾波场加速。提出了该过程的理论分析，并通过粒子模拟进行了验证。仿真表明，可以获得相对较高电荷的准单能正电子束。