Upgrading of the SPS injection kicker system for LHC requirements

The present SPS injection kicker system is composed of 12 travelling wave magnets connected in pairs to six pulse generators. The eight most upstream magnets ('S'-type) have a kick rise time (2-98%) o f 145 ns and the remaining four ('L'-type) of 215 ns. The flat top ripple of the kick is ±1%. In the future, this system will also inject protons and ions for the LHC, with a bunch spacing of respect ively 220 ns and 125 ns, and a flat top ripple requirement of at most ±0.5%. Important modifications, concerning both magnets and generators, are then required to meet these goals. For ion injection only 'S'-type magnets will be used. The reduction of the kick rise time will be achieved by shortening the magnet length and increasing the characteristic impedance. To compensate for the loss in tota l kick strength, four new magnets and two new pulse generators will be added. At the moment it is not intended to modify the 'L'-type magnets. Most of the pulse forming networks (PFN's) must be adapt ed to the higher characteristic impedance of 16.67 W. The internal structure of all PFN's will be upgraded to reduce the flat top ripple and improve the turn-on characteristics.