Protection gas gaps testing and calculation of breakdown voltage of accelerator inner structures

Test results of discharge gaps of the Eh G-2.5 high-voltage accelerator in N2 - CO2, C Cl2 F2 and S F6 gases are presented. The technique of calculation of breakdown voltage for the 3 - 4 mm gaps is suggested. The technique allows to estimate the electric strength of hundreds of internal gaps with parallel connection and the reliability of operating and developing accelerators, as well. The calculation accuracy is ± 5%. 7 refs