How wrong is collisional Monte Carlo modeling of fast electron transport in high-intensity laser-solid interactions?
How wrong is collisional Monte Carlo modeling of fast electron transport in high-intensity laser-solid interactions?
复制标题
DOI：
10.1103/physreve.65.026407
复制
发表时间：
2002-02-01
影响因子：
2.4
通讯作者：
Davies, JR
中科院分区：
文献类型：
--
作者：
Davies, JR
高强度激光与固体靶的相互作用产生了大量的快速电子流流入靶中。由于电流的大值，快速电子在目标中产生显著的电场和磁场，并迅速将其加热到高温。然而，这些效应在解释X射线发射实验时被忽略了，因此推断出的快速电子产生的细节可能是不正确的。这被认为是，从理论上讲，分层目标，Ka发射实验，通过使用混合蒙特卡罗代码，包括字段生成。该代码是用来模拟这样的实验与铝和塑料目标，使用快电子参数采取前面的实验结果，平均强度约为10（18）W cm（-2）。这些数值结果，然后解释与以前的实验相同的方式，只使用Monte Carlo部分的代码。场的产生导致较低的总发射和一个明显的两个温度的快速电子分布。通过蒙特卡罗模型推断的快电子对激光的吸收始终低于实际值。平均快电子能量推断可能高于或低于实际值，这取决于实验设置和Monte Carlo建模中使用的锥角和能量分布。一般来说，忽略磁场所引起的误差对于塑料目标比铝目标更大，从而导致通过Monte Carlo建模获得的结果不一致。
The interaction of a high-intensity laser with a solid target generates a large current of fast electrons flowing into the target. Due to the large value of the current, the fast electrons generate significant electric and magnetic fields in the target and rapidly heat it to high temperatures. However, these effects were neglected in interpreting x-ray emission experiments, so the details of the fast electron generation that were inferred could be incorrect. This is considered, theoretically, for layered target, Kalpha emission experiments, by using a hybrid Monte Carlo code that includes field generation. The code is used to model such experiments with aluminum and plastic targets, using fast electron parameters taken front experimental results For average intensities of around 10(18) W cm(-2). These numerical results are then interpreted in the same manner as previous experiments, using only the Monte Carlo part of the code. The field generation leads to lower total emission and to an apparent two-temperature fast electron distribution. The laser absorption into fast electrons inferred by Monte Carlo modeling is consistently lower than the actual value. The mean fast electron energy inferred could be either higher or lower than the actual value, depending on the experimental setup and the cone angle and energy distribution used in the Monte Carlo modeling. The errors caused by neglecting the fields are, in general, greater for plastic than aluminum targets, leading to inconsistencies in results obtained by Monte Carlo modeling.