A full-DC injector for an energy-recovery linac

We propose a full-DC injector for an energy-recovery linac. The injector is based on a 2 MeV DC accelerator that is commercially available (Dynamitron type), combined with a photo cathode. A bunched beam from the DC accelerator is merged with a recirculating beam and injected into a superconducting buncher-booster, which accelerates the beam up to ∼20 MeV. The buncher-booster is operated in partial energy-recovery mode, in which we can reduce the capacity of the RF generators to 10 kW even for a high-average current operation, 100 mA. We present results of beam dynamics simulation and RF system optimization.