Electrical strength of the high-voltage gaps of the tandem accelerator with vacuum insulation

New type of accelerator — electrostatic tandem accelerator with vacuum insulation — was proposed and constructed for boron neutron capture therapy (BNCT). The accelerator has a high acceleration rate of charged particles, which gives hope for its stable operation without breakdowns at high currents. Specialties of the accelerator are large surface area of the accelerating electrodes (41 m 2 ) and large stored energy (tens of joules). The results of experiments, carried out on the high-voltage stand and the tandem accelerator, are presented. The influence of breakdowns on the electrical strength of the high-voltage accelerator elements are studied. This investigation allows increasing proton energy up to 2.3 MeV and current up to 5 mA.