The Rhic Beam Abort Kicker System*

The energy stored in the RHIC beam is about 200 kJ per ring at design energy and intensity. To prevent quenching of the superconducting magnets or material damage, the beam will be safely disposed of by an internal beam abort system, which includes the kicker magnets, the pulsed power supplies, and the dump absorber. Disposal of heavy ions, such as gold, imposes design constraints more severe than those for proton beams of equal intensity. In order to minimize the thermal shock in the carbon-fiber dump block, the bunches must be laterally dispersed. The nominal horizontal beam deflection angle is required to vary from ~1.7 to 2.5 mrad, which is obtained from five 1.22 m long kicker modules operating at a magnetic field of ~3.5 T. The kickers are constructed as window frame magnets with an 50.8 by 76.2 mm aperture and are operated in the ring vacuum. The pulsed power supplies run at 33 kV and deliver the 12.8 μs long pulse. The peak current required is ~21 kA and the 50% modulation is generated by means of a pulse forming network with non-uniform characteristic impedance.