A Ring Cyclotron Kaon Factory

A two stage isochronous ring cyclotron is proposed for accelerating a 100 ¿A proton beam to 8.5 GeV. The first stage of 15 sectors and 10 m radius would take a 450 MeV beam from TRIUMF to 3 GeV, the acceleration being completed by a second stage of 30 sectors and 20 m radius. Superconducting magnets would be used, the weight of steel being estimated to be 2000 m tons for the first stage and 1800 m tons for the second. Numerical orbit tracking through simulated magnetic fields has confirmed that the focusing properties of the design are satisfactory and has emphasized the importance of using small pole-gaps to prevent fringing field effects weakening the edge focusing. Steel is provided outside the coils on the focusing edge to help keep it hard and increase the flutter. The accelerating system consists of SIN-style cavities, with flat-topping provided by operating some at the second harmonic (first stage) or third harmonic (second stage). The phase compression effect is also utilized to allow higher fundamental frequencies to be used on successive stages.