Construction and testing of an 11.4 GHz dielectric structure based travelling wave accelerator

One major challenge in constructing a dielectric loaded travelling wave accelerator powered by an external RF power source is the difficulty in achieving efficient coupling. In this paper, we report that we have achieved high efficiency broadband coupling by using a combination of a tapered dielectric section and a carefully adjusted coupling slot. We are currently constructing an 11.4 GHz accelerator structure loaded with a permitivity=20 dielectric. Bench testing has demonstrated a coupling efficiency in excess of 95% with bandwidth of 600 MHz. The final setup will be tested at high power at SLAG using an X-band klystron RF source