Design of intense L-band electron Linac

Abstract

An intense L-band traveling-wave electron accelerator is under development for irradiation applications. It is capable of producing 10-MeV electron beams of 30 kW under a fully beam-loaded condition. The accelerator is powered by a pulsed klystron of 1.3 GHz and 25 MW with a 60-kW average power. The accelerating structure is a constant-impedance, disk-loaded structure operated with the 2 pi/3 mode. The RF cavities in the accelerating structure were designed by using the SUPERFISH code. Cold tests were also conducted for every kind of prototype cavities with different dimensions in the accelerating structure. A beam dynamics simulation by the PARMELA code indicates that the beam transmission efficiency, the ratio of the input to the output currents, is over 90 % with solenoid fields from the POISSON code. With the simulation, we obtain the fully-beam-loaded condition at an input beam current of 1.6 A.