The simulation and optimization of a room-temperature Cross-Bar H-Type Drift-Tube Linac

The room-temperature Cross-Bar H-Type Drift-Tube Linac (CH-DTL) is one of the candidate accelerating structures, working at 325 MHz in CW mode, for the Chinese ADS project. In this study the multi-cell cavity geometry has been optimized using the method of 'parameter sweeping with constraint variable' which is found superior to parameter sweeping with a single variable. To facilitate manufacture, a spherical drift tube shape is adopted. It can be concluded that a cavity having cylindrical end cups has higher shunt impedance than one with cone-shaped end cups