Beam Dynamics Simulation in SC Linac for the Proton Radiotherapy

Superconducting linear accelerators based on short independently phased SC cavities are widely used today in ADS and FRIB. Such accelerator can be useful as a proton therapy beam source [1]. The accelerator general layout to accelerate proton beam at the energy range 2-240 MeV will detail in this report. Obviously, in this linac will always violate the principle of synchronicity when the synchronous particle velocity is equal to the phase velocity of the accelerating wave and a slipping of particles relative to the accelerating wave. The beam dynamics simulation shows that linac should consist of four groups of identical cavities. Cavities should have phase velocities as βg = 0.1, 0.18, 0.3 and 0.49 respectively. The choice of optimum parameters of accelerating cavities and focusing magnets will discussed and the beam dynamics simulation results will presented.