Abstract: A broad-beam high energy electron accelerator has an electron injection section arranged for increased current density with greater uniformity and higher transmission through the foil exit window. A plurality of cathode rods are disposed in a transverse plane and spaced at about 2.4 cm, and a reflector plate behind the cathode rods is biased negative relative thereto. A planar control grid is disposed distal of said cathode rods and a screen grid is disposed parallel to and distal of the control grid. Field-shaping wires are disposed in a plane parallel to the plane of the cathode rods and between the same and the reflector plate, with the respective field-shaping wires being disposed parallel to said rods and midway between them. The same positive bias (e.g., 11 kV) is applied to both the control grid and the field-shaping wires.

Abstract: Methods and apparatus for producing intense megavolt ion beams are disclosed. In one embodiment, a reflex triode-type pulsed ion accelerator is described which produces ion pulses of more than 5 kiloamperes current with a peak energy of 3 MeV. In other embodiments, the device is constructed so as to focus the beam of ions for high concentration and ease of extraction, and magnetic insulation is provided to increase the efficiency of operation.