Design, analysis and measurement of very fast kicker magnets at SLAC

Recent experience with SLC (Stanford Linear Collider) has shown that very fast, ferrite-loaded, transmission-line, beam-kicker magnets can cause significant and undesirable distortion of a 1.5-2.5-kA, 20-40-kV pulse as it travels through the magnet. In general, there is a net lengthening of the pulse, with increases in its rise and fall times, a decrease in amplitude, and an unsymmetrical rounding of the flat top. A number of practical design considerations are discussed in terms of equivalent circuits, magnet circuit dispersion and dissipation, undesired circuit shunting and coupling, high-voltage breakdown problems and high-order-mode losses that lead to beam tube heating. These effects are linked to the properties of the materials, the presence of radiation, and realizable magnet topologies. Measurements and calculations of some of these characteristics for several magnet design are reviewed. >