适用于中等耦合等离子体的碰撞算子

完全电离等离子体中，当试探粒子分布函数fα是关于试探粒子速度vα的偶函数时，导出了一个新的动力学方程的碰撞算子．该碰撞算子同时包括了大角散射（库仑近碰撞）和小角散射（库仑远碰撞）的二体碰撞的贡献，因此，该碰撞算子同时适用于弱耦合（库仑对数ln∧≥10）和中等耦合（库仑对数2≤ln∧≤10）等离子体．而且经过修改的碰撞算子和Rosenbluth势有直接的联系，当试探粒子和场粒子满足条件mα＜mβ（如电子-离子碰撞或Lorentz气体模型）和｜vα｜〉｜vβ｜时，经约化的电子-离子碰撞算子同最初的Fokker

A new approach has been developed to treat large-angle and small-angle binary collisions in plasmas when the test particles' distribution function f(alpha) is an even function about the test velocity v(alpha). In the approach, the Boltzmann collision operator is derived to be suitable for the plasma considered as weakly coupled (Coulomb logarithm In Lambda >= 10) or moderately coupled (2 <= ln Lambda <= 10). The modified collision operator has a direct and practical connection to the Rosenbluth potentials. In addition, with m(alpha) << m(beta) (such as electron-ion collision or Lorentz-gas model) and vertical bar v(alpha)vertical bar >> vertical bar v(beta)vertical bar, the reduced electron-ion collision operator differs from the original Fokker-Planck operator for Coulomb collisions by terms of order 1/ln Lambda