A thin superconducting solenoid for use in a phase rotation induction linac

One of the proposals for delivering a cooled muon beam to a muon collider o r a high intensity neutrino source uses an induction Linac to phase rotate the muons that result from the decay of pions produced by a high intensity proton beam on a target, An induction linac with an acceleration gradient o f 2MV per meter is proposed to produce bunches of muons that have a momentu m of 200 MeV/c. The induction accelerator is assembled around the 3T superc onducting solenoids needed to contain the muon beam. The superconducting so lenoid must have a warm 100-mm gap at 1000-mm intervals down the phase rota tion channel. The acceleration structure for the induction linac is around this gap. The superconducting solenoid will have an Inside warm radius of 2 01 mm, The thickness of the superconducting magnet and its cryostat must be about 60 mm near the acceleration gap. An access region of 85 mm between i nduction linac sections is allowed for the superconducting coil cold mass s upports, the electrical leads and the supply of cryogenic cooling. This rep ort presents a design for a 3 T phase rotation induction linac superconduct ing magnet system, its cryostat, and its cooling system.