Abstract

The applicability of the collision kinetic model of point sinks, viz., the linearized theory of screening of the electric field produced by a charged dust particle, based on the Vlasov equations for electrons and ions in a nonequilibrium plasma, which are supplemented with collision terms in the Bhatnagar–Gross–Crook form and effective point sinks to dust particle, is analyzed. The criterion for the applicability of the collision kinetic model of point sinks is the smallness of the deviation of the electron and ion number densities near an absorbing spherical body from unperturbed values. The distributions of electron and ion number densities obtained using the collision kinetic model of point sinks and the orbit motion limited approach are compared. It is shown that the latter approach is applicable only in the low-pressure limit, and upon an increase in pressure, the Coulomb asymptotics of the potential, which is proportional to the frequency electron and ion collisions with neutral atoms (molecules), renders the orbit motion limited approach inapplicable for calculating the ion distribution. It is established that the domain of applicability of the collision kinetic model of point sinks is close to the applicability domain of the Debye–Hückel theory.

中文翻译：

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非平衡等离子体中吸收球体附近的电子和离子的分布

摘要

点汇碰撞动力学模型的适用性，即基于非平衡等离子体中电子和离子的Vlasov方程，对带电尘埃粒子产生的电场进行屏蔽的线性化理论，其中补充了碰撞项分析了Bhatnagar–Gross–Crook形式的有效点，并沉降到尘埃颗粒的有效点。点汇碰撞动力学模型适用性的标准是，吸收球体附近的电子和离子数密度与未扰动值之间的偏差较小。比较了使用点汇碰撞动力学模型和轨道运动受限方法获得的电子和离子数密度的分布。结果表明，后一种方法仅适用于低压极限，随着压力的增加，电势的库仑渐近性正比于电子和离子与中性原子（分子）碰撞的频率，这使得轨道运动受限方法不适用于计算离子分布。可以确定，点汇碰撞动力学模型的适用范围接近Debye-Hückel理论的适用范围。