【作者】 查学军； 韩申生； 徐至展；

【Author】 Zha Xuejun, Han ShenSheng, Xu Zhizhan Shanghai Institute of Optics and Fine Mechanics, P.O.Box 800-211, Shanghai 201800, China

【机构】 中国科学院上海光学精密机械研究所；

【摘要】 在近几年提出的几种快点火方案中,一个重要的关键问题是能量输运在物理上的不确定性,即高能量超短超强激光产生的强流相对论性的电子束(电流强度I～100MA,电子能量E～MeW)在高密度背景等离子体中的输运机制。强流高能带电粒子束在超高密度等离子体中的传输具有两个基本的特征,其一是电流密度大大超过Alfven电流极限, 其二是在超高密度等离子体中传输,其传输具有很强的磁流体力学不稳定性。该电子束流输运问题可由磁流体力学模型求解,其方程组由相对论性电子束流的输运方程组、麦克斯韦方程组和高密度背景等离子体 (或高Z等离子体)流体方程组构成,其中相对论性电子束流的输运方程组由相对论性的Fokker-Planck方程导出。通过数值求解这一整套磁流体力学方程组,可给出高能超强激光产生的强流相对论性电子束(电流强度I～100MA,电子能量E～MeV)在超高密度等离子体中的能量沉积和宏观不稳定性的解。更多还原

【Abstract】 In all FI schemes proposed in recent years, energy transport is the key area of physics uncertainty, i.e. what is the transport mechanism for high-current relativistic Electron (proton) beam (current intensity ~ 100MA, electron energy ~ MeV) in the presence of a background overdense plasma. The transport for high-current relativistic Electron (proton) beam has two basic characters, the first is that the forward current is larger than 100 MA and exceeds beyond the Alfven current limit; the second is the propagation of high-current relativistic Electron beam in the presence of a background overdense plasma has very strong MHD instability. The transport problem can be solved MHD equations that describe the dynamic, self consistent collisional and electromagnetic interaction of relativistic electron beam with overdense plasmas or high atomic-number plasmas. The full set of equations consist of the relativistic beam transport equations which are coupled to Maxwell’s equations through the electromagnetic-field terms and to dynamical equations for the plasma through the collision term. Because of their complexity, solutions of the full set require the use of numerical techniques.更多还原