SwissFEL C-Band Test Stand

The main accelerator of SwissFEL will use accelerating copper structures that will operate at 5.7 GHz (C-Band). Four of these 2 m long structures form a linac module and a total of 26 of these modules will be installed in SwissFEL. Each linac module is powered by an RF source that consists of a solid-state modulator and a klystron in which RF pulses are generated with 100 Hz with a maximum power of 50 MW and a nominal pulse duration of 3 microseconds. In order to increase the efficiency of the linear accelerator, the RF pulse from the klystron is compressed by an RF pulse compressor after which an RF peak power of more than 300 MW can be reached. This compressed RF pulse is then distributed by a waveguide network to the four accelerating structures of the module.

In order to test the different components required for a linac module, PSI operates a C-band test stand. The test stand is divided into two parts: In the first part, single prototype components can be tested under high RF power, while the second part will be used to test a prototype of a complete accelerating module.