Performance of the hermes-III gamma ray simulator

Hermes III is a 22-MV, 730-kA, 40-ns pulsed power accelerator that drives an electron beam diode/converter to generate an intense pulse of bremsstrahlung radiation. In Hermes III, eighty individual 1.1-MV, 220-kA pulses are generated and added in groups of four to develop twenty 1.1-MV, 730-kA pulses which are then fed through inductively isolated cavities and added in series by a magnetically insulated transmission line (MITL). An extension MITL delivers this surnmed output to the electron beam diode. The construction of Hermes III was completed February 1988 and was followed by an accelerator characterization and performance demonstration phase. Hermes III met all of its performance requirements during this testing period and has gone operational one year ahead or schedule. An overview of the Hermes-III design is presented together with details of the performance obtained for the various subsystems. A discussion of future applications of this technology is also presented.