Photoelectron Emission on Polyimide Films Irradiated by Proton

The dielectric characteristics of the surface material of the spacecraft, such as secondary electron emission (SEE) and photoelectron emission (PE), are required for high reliability of spacecraft generation. Those materials are deteriorated due to radioactive rays irradiation on orbit. Those values may be changed from the situation. When we want to estimate surface changing at the end of life (EOL) of satellite with accuracy, we need to give values of PE and SEE at EOL situation. In this report, we irradiated the proton beam to insulating materials and measured PE on the aged sample. We examined the relationship between the irradiation dose and PE.