High-Voltage Gaps in a Tandem Electrostatic Accelerator with Vacuum Insulation

Theoretical and experimental results on the development and testing of a system of high-voltage vacuum accelerating gaps with electrode areas of several tens of square meters are presented. The energies stored in individual gaps may reach several tens of joules. The work is carried out as part of a program aimed at the development of a tandem electrostatic accelerator with vacuum insulation designed for a proton energy of 2.5 MeV and current of several tens of milliamperes. Optimization of the high-voltage part of the tandem with respect to the overvoltage arising in high-voltage elements of the tandem during its full or partial breakdown and to the energy stored in capacitors formed by the vacuum accelerating gaps and related elements of the tandem is considered. Experimental data on the electric strength of a 45-mm vacuum gap for different energies released in the breakdown are presented. For an electric field intensity of several tens of kilovolts per centimeter, the value of the field-emission current in a high-voltage gap with electrodes of a large area is estimated.