Very high pulse-energy accelerators

The design and performance of the Hermes III are presented and the application of this technology to the light ion beam inertial confinement fusion program is discussed. Hermes III represents a new approach to efficiently generating higher voltages. It is designed to drive a 22-MV, 730-kA, 40-ns electron beam diode and combines conventional, modular pulsed power technology with linear induction acceleration concepts. High-power induction accelerator cavities are combined with voltage addition along a MITL (magnetically insulated transmission line) to generate the desired output. This design differs from a conventional linac in that the voltages are added by the MITL flow rather than by a drifting beam that gains kinetic energy at each stage. The design is a major extrapolation of previous state-of-the-art technology represented by the injector module of the Advanced Test Accelerator and has proven to be efficient and reliable. A key issue for ion beam applications relates to the efficiency of coupling power from the high-voltage MITL to an extraction ion diode. A conceptual design of a light ion beam driver for the LMF (Lase Microfusion Facility) has been developed