中文摘要：

空间微小碎片超高速撞击航天器表面可产生稠密的等离子体,随着等离子体的扩散可导致静电放电及电磁干扰脉冲的发生,近而威胁航天器在轨安全.本文利用等离子体驱动微小碎片加速器研究了质量为10 5g的空间碎片撞击产生的等离子体基本特性,给出了等离子体总电荷与微小碎片速度之间的关系,获得了等离子体扩散速度参数及等离子体电子密度随时间和空间的演化关系,研究结果对于揭示空间微小碎片撞击诱发放电和电磁干扰脉冲形成的机理具有重要意义.

英文摘要：

Dense plasma cloud can be produced by small debris impact on spacecraft surface,with the difusion of plasma which can induce the electrostatic discharge（ESD） and electromagnetic interference（EMI）.By this way,spacecraft will experience electrical anomalies.In this paper,a plasma drag particle accelerator is used to study the characteristics of impact-generated plasma due to crash of small debris with mass 10 5g.The relation between plasma charge and debris velocity is acquired by analyzing experimental data.In addition,the difusion velocity of the impact-generated plasma is observed by two retarding potential analyzers.By theoretical analysis,the change law of the electron density with time and dimension is calculated.Experiment results will be helpful to reveal the physical mechanism of spacecraft anomalies by small debris impacts.