Mechanical design of fast extraction kicker and PFN for SNS accumulator ring

Two kicker assemblies, seven pulsed magnet modules in each assembly, will be used in the SNS accumulator ring to kick the beam vertically to the extraction septum then to the target. These kickers are designed as window frame magnets housed inside a vacuum chamber. Fourteen pulse forming networks (PFN) housed in separate silicon fluid containers are designed to power each kicker module. A single module prototype kicker magnet and PFN modulator have been successfully assembled and tested. In this paper we discuss the mechanical design criteria of these kicker assemblies, the installation layout in the accumulator ring, the structural analysis of the kicker chamber, the magnetic field analysis of the ferrite magnet, the high voltage feedthrough design, the structural design of the modulator container, the cooling and the thermal expansion considerations of the silicon fluids.