Development for a supercompact <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>X</mml:mi></mml:math>-band pulse compression system and its application at SLAC

Abstract

We have successfully designed, fabricated, installed, and tested a super compact $X$-band SLAC Energy Doubler system at SLAC. It is composed of an elegant 3 dB coupler--mode converter--polarizer coupled to a single spherical energy storage cavity with high ${Q}_{0}$ of 94000 and a diameter less than 12 cm. The available rf peak power of 50 MW can be compressed to a peak average power of more than 200 MW in order to double the kick for the electron bunches in a rf transverse deflector system and greatly improve the measurement resolution of both the electron bunches and the x-ray free-electron laser pulses. The design physics and fabrication as well as the measurement results will be presented in detail. High-power operation has demonstrated the excellent performance of this rf compression system without rf breakdown, sign of pulse heating, and rf radiation.