Development of Analyzing and Monitoring System for Charging Process in Dielectric Material in Space Environment.

用PIPWP方法观察了电子束辐照下PMMA中的电荷积累过程。为了观察充电过程的特点，对PIPWP法的装置进行了改造。利用改进后的系统，在电子束辐照下对PMMA中的电荷分布进行了5 min的真实的时间测量。随着辐照时间的增加，注入PMMA的电子量明显增加。根据电荷分布的结果，还计算了电场和电势的变化。此外，观察到照射后电荷分布的衰减。从这些结果证明了辐照过程中的真实的时间测量是可能的。换句话说，在不久的将来可以开发出电子束辐照的监测系统。

Charge accumulating process in PMMA under electron beam irradiation was observed using the PIPWP method. To oberve the characteristics of charging process, the apparatus of PIPWP method has been modified. Using the improved system, the real time measurement of charge distribution in PMMA was carried out under electron beam irradiation for 5 minutes. The increase of the electrons injected into PMMA was clearly observed with increase of the irradiation time. From the results of the charge distribution, the change of the electric fields and potential were also calculated. Furthermore, the decay of the charge distribution after irradiation was observed. From these results, it is proved that the real time measurement during irradiation is possible. In other words, a monitoring system of electron beam irradiation can be developed in near future.