A study on stabilizing the operation of a large-scale electron linear-accelerator

A synchronized RF timing system and a beam energy compression system have been introduced to the 1.2 GeV electron linear accelerator, which is an injector for the synchrotron radiation source SPring-8, for improving the stability of the output beam. The timing system is comprised fundamentally of an arbitrary-waveform-generator and a frequency multiplier. The rms phase fluctuation of accelerating rf is improved to be 0.22 degree. The beam energy compression system consists of four chicane magnets and an accelerator structure. Energy spread of the beam causes a spread of path length when the beam passes through the chicane magnet system, and can be compressed in the following accelerator structure. The stability of the output beam energy is improved to be 0.01%. (author)