Fast Kicker Magnets for the 200-GeV Accelerator

Several fast-transfer systems using kicker magnets are needed for the proposed 200-GeV Accelerator. A possible system for transfer from the injector synchrotron to the main ring using stationary, full-aperture kicker magnets presents the most stringent requirements. The extraction kicker for the injector synchrotron will be about 4 m in length, have a 4-by-14-cm aperture, and require a field or 300 G. For 100% efficient transfer the rise time of the magnetic field must be shorter than 17 ns, which is the time between beam bunches, and which is nearly an order of magnitude less than the rise times achieved in existing kicker magnets. Because of the required rise time and the limited length, each magnet is divided into 48 modules operated as 24 push-pull pairs. Each module is analyzed as a short-circuited ferrite-and dielectric-loaded transmission line. The short-circuited mode of operation ensures that voltage on the magnet is applied for only about 12 ns, thus reducing HV problems, and at the same time produces a kick twice as great as can be obtained from terminated magnets. Each module is energized by a tapered coaxial pulse line and switched on with a triggered spark gap.