激光等离子体中的自生磁场和质子加速

Self-Magnetic Field and Proton Acceleration in a Laser Plasma Interaction

选用不同类型的等离子体薄靶,用二维particle-in-cell(PIC)粒子模拟方法系统研究了超强激光脉冲与等离子体薄靶相互作用中产生的自生磁场和质子加速行为,结果发现:当功率密度为1020W/cm2的超强激光与等离子体薄靶相互作用时,由于等离子靶面所产生的自生磁场作用使产生的质子分布呈现空间定向发射,发射的方向和高能质子能量与等离子体靶面密切相关,能量越高发散角越小,而质子加速越好。在圆形薄靶中质子最大能量达到41.1 Me V。研究结果对惯性纳米聚变快点火和肿瘤治疗等方面具有重要的应用价值。

By selecting different types of thin plasma targets and applying two-dimensional particle-in-cell（PIC）simulation system, the acceleration behaviour of proton in the self-generated magnetic field induced by ultra intense laser and the thin plasma target interaction are studied. The results show that when the power density of interaction of intense laser is 1020W/cm2, due to the self-generated magnetic field produced plasma target, the proton distribution exhibites space directional emission; the emission direction and the energy of the high energy proton are closely related to the plasma target surface. The higher proton energy, the smaller the divergence angle and the better proton accelerator effect are. In the round thin plasma target, the proton maximum energy reaches 41.1 Me V. This result has important application value for the inertial nano fusion fast ignition and tumour therapy.