空间尘埃的充电过程及与等离子体参数的关系

考虑了地球附近的彗星、行星环、行星际介质等空间尘埃等离子体环境中尘埃颗粒的充电问题．应用典型的空间尘埃等离子体参数，计算了不同种类的尘埃颗粒，以及不同等离子体成分下等离子体中尘粒的平衡电势，得到了尘埃颗粒的平衡电势与尘埃等离子体成分、温度，及其他等离子体参数之间的相互关系．

CHARGING PROCESS OF SPACE DUST AND ITS DEPENDENCE UPON PLASMA PARAMETERS

Dust grains immersed in plasma will be charged of various charging currents, this paper considers three main currents due to the relative velocity between the dust grains and the plasma: the primary ions, the primary electrons, and the sec-ondary electrons. The surface potentials of silicate and carbon dusts grains in H+ and H2O+ plasma environments are calculated using universal plasma parameters, these plasma conditions are common in space environments, such as comets, plan-etary rings, and interplanetary media. A conclusion is found that the equilibrium potential of dust grains have close correlation with the plasma temperature. At low temperatures, the surface potential will become lower while the temperature rises. The dust can reach a positive potential when the temperature is high enough. The potential of carbon grains is lower than that of silicate grains. The component of plasma may affect the potential, too. For both silicate and carbon grains, potential in H+ plasma is higher than that in H2O+ plasma.