Relativistic Klystron Amplifier at 2.25 GHz

Summary form only given. We recently performed a relativistic-klystron oscillator experiment (RKO) at 400 MHz. The electrical generator we used is capable of generating a 700 kV, 15 kA, 100 ns annular electron beam. Now, with the same source, an amplifier experiment is in progress at 2.25 GHz. The first RKA cavity is a cylindrical pill-box which is fed by an external RF signal provided by a low-power (100 MW) vircator. This vircator uses a simple electrical generator (Marx capacitor bank) to provide a 200 ns-long reliable and reproducible input driver pulse. When we fire the two generators together, we measure the jitter to be less than 5 ns. We present in this paper a calculation of this experiment using the code MAGIC, as well as the preliminary experimental results