Modern, multi-modular plasma modeling requires accurate and versatile methods for the determination of the electron velocity distribution function from which rate coefficients of electron impact processes as well as electron transport quantities are determined. In this paper we propose as a solution a modified version of a strongly overlooked method developed in the early 90's, namely, Monte Carlo Flux (MCF). The improvement lies in a criterion for the otherwise somewhat empirical selection of the time-step used in the method. We show that an MCF based code highlights and overcomes the limitations of two-terms codes such as BOLSIG+ and it is much faster than a conventional Monte Carlo. Moreover, MCF is in excellent agreement with the multi-term method for a wide range of reduced electric fields, being at the same time much simpler to implement and to extend to more general cases than the latter. Explicit illustrations of the Markov matrices representing short-time kinetics are presented to gain insight into the method. The two-dimensional velocity distribution and its expansion into Legendre polynomials are discussed for electrons in argon.

中文翻译：

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使用 Monte Carlo Flux 模拟获得的电子速度分布函数的基准计算

现代的多模块等离子体建模需要准确和通用的方法来确定电子速度分布函数，从中可以确定电子撞击过程的速率系数以及电子传输量。在本文中，我们提出了一种解决方案，即 90 年代早期开发的一种被严重忽视的方法的修改版本，即蒙特卡罗通量 (MCF)。改进在于该方法中使用的时间步长的其他一些经验选择的标准。我们展示了基于 MCF 的代码突出并克服了 BOLSIG+ 等两项代码的局限性，并且它比传统的蒙特卡罗快得多。此外，MCF 与用于大范围减小电场的多项方法非常一致，同时比后者更容易实现和扩展到更一般的情况。展示了代表短时动力学的马尔可夫矩阵的明确说明，以深入了解该方法。讨论了氩气中电子的二维速度分布及其向勒让德多项式的扩展。