Properties of polyimide film after electron beam irradiation with a dose of 1 GGy

The results of the performance tests of a three-layer foil separator for a high-current electron gun of an ELA excimer laser are presented. The separator consisted of two layers of thin titanium foil with a polyimide film between them. Such a composition withstood 5630 electron beam pulses with duration of 80 ns and an energy density per pulse of about 9 J/cm$^2$. In this case, the polyimide film (Dupont Kapton polyimide film) with a thickness of 38 $\mu$m was irradiated with a dose of 1 GGy. The initial and induced absorption of this film was measured in the range from 20 to 0.4 $\mu$m. The mechanical tensile strength of the irradiated film decreased by 17 times.