Bench test of fast kicker for bucket-by-bucket on/off-axis injection

Ultra-low emittance rings like the SPring-8 II ring planed at SPring-8 have very narrow dynamic aperture of less than 2 mm even with very large beta function ∼ 25m at injection point. For this aperture, it is difficult to apply conventional injection schemes with septum and bump magnets, and also pulsed quadrupole or sextupole magnet injection because of the large perturbation on stored beam with quadrupole, or required very strong magnet for sextupole. We proposed the bucket-by-bucket on/off-axis injection scheme with variable field fast kicker. The prototype of the kicker has been already constructed and the bench test is in progress for the beam test with the SPring-8 linac beam. In this report, the structure of the kicker, the calculated kick field with the structure, and the result of the low level measurement and of the high power/voltage test is described. (author)