碰撞效应对超强激光与高密度碳薄膜靶相互作用中快电子输运的影响(英文)

Collisional effects on hot electron transport in a dense solid carbon thin foil irradiated by ultrahigh intensity lasers

在激光驱动粒子加速和快点火背景下,用带碰撞模块的1维粒子模拟程序,研究了高功率亚ps激光与高密度(近固体密度)碳薄膜靶相互作用中的碰撞效应。研究表明,通过和无碰撞粒子模拟结果的比对,在早期瞬态时段,碰撞效应通过慢化提供电阻加热的回流对快电子产生和输运起重要作用。定性上,碰撞效应还减少快电子的产额和最大能,抑制能量输运。然而,在加热后期当往返运动成为主要输运机制时,有碰撞和无碰撞两种情况的差别减小。

Collisional effects on the kinetics of interactions between an ultrahigh intensity subpicosecond laser and a solid carbon thin foil are investigated in the scenarios of laser-driven particle acceleration and fast ignition by one-dimensional particle-in-cell simulations.It is found that collisional effects play an essential role in hot electron generation and transport in the early transient time by slowing down the return current which supplies resistive heating,compared with collisionless cases.Qualitatively,collisional effects reduce hot electron production and its maximum energy,and suppress energy transport.However,when recirculation（or refluxing） processes become the major transport mechanism in later time,the two cases have less difference.