The dynamics of the spacecraft potential during electron beam injection

In interpreting the results of active space experiments with charged particles injected in the near Earth space it is important to determine the change of potential of the injecting spacecraft and the disturbed plasma characteristics in its vicinity. The structure of the plasma-beam system in the vicinity of a beam-injecting spacecraft is rather intricate. APEX was a diversified project with an emphasis on the neutralization problem and the dynamics of the spatial charge zone of spacecraft. Since the injection heights range was from 400 to 3,500 km where additional neutralization mechanisms do not work there was a possibility to study the total scope of the above mention problems. It is shown that by changing the injection current in accordance with a certain law we can obtain a medium with the required properties in the spacecraft environment. A comprehensive analysis will allow an appropriate injection regime to be selected. The time and space variations of electron density in space charge zone of spacecraft are determined by the magnitude and the sign of injected current variations as well as by the experimental parameters.
JAXA Special Publication
宇宙航空研究開発機構特別資料