Cold test of compact C-band standing-wave accelerating structures

We designed and fabricated a C-band standing-wave accelerating structure for a compact industrial electron accelerator. It is capable of producing 4-MeV electron beams with 50-mA pulsed beam current. As an RF source, we use a 5-GHz magnetron with 1.5-MW peak power and 0.08% duty factor. This structure is bi-periodic and operated with the pi/2-mode standing-waves. It is on-axis coupled with magnetic coupling slots on the side wall. Each cavity in the bunching and the normal cells is designed by using the MWS code. The coupler cell is designed by using the Omega3p code for determining the resonant frequency and the external Q². With the measurement of the aluminum prototype cavities, we determined the final dimensions for actual OFHC-copper cavity. In this paper, we present the low-power measurement results for the actual column: the pi/2-mode resonant frequency, the coupling coefficient, and distribution of the field strength.