The mechanism for emergence of helical electron bunch(HEB) from an ultrarelativistic circularly polarized laser pulse propagating in near-critical density(NCD) plasma is investigated. Self-consistent three-dimensional(3D) Particle-in-Cell(PIC) simulations are performed to model all aspects of the laser plasma interaction including laser pulse evolution, electron and ion motions. At a laser intensity of 1022 W/cm2, the accelerated electrons have a broadband spectrum ranging from 300 MeV to 1.3 GeV, with the charge of 22 nano-Coulombs(nC) within a solid-angle of 0.14 Sr. Based on the simulation results, a phase-space dynamics model is developed to explain the helical density structure and the broadband energy spectrum.
展开▼
机译：研究了在近临界密度（NCD）等离子体中传播的超相对论圆偏振激光脉冲产生螺旋电子束（HEB）的机理。进行自洽的三维（3D）单元内粒子（PIC）仿真以对激光等离子体相互作用的所有方面进行建模，包括激光脉冲演化，电子和离子运动。激光强度为10 22 W / cm 2 时，加速电子的宽带光谱范围为300 MeV至1.3 GeV，电荷为22纳米库仑（ nC）在0.14 Sr的立体角内。根据仿真结果，建立了相空间动力学模型来解释螺旋密度结构和宽带能谱。
展开▼
