Radiation Resistant Magnet Coils from Hard Anodized Aluminum Conductor

An extracted beam current of ~ 25 ¿A of ~ 575 MeV protons from the modified Nevis Synchrocyclotron will strike two meson producing targets before coming to rest in a beam stop. The quadrupole and dipole transport magnets viewing the targets at close range might absorb 1010-1011 rad/yr. or more. Conventional coil insulating techniques employing epoxy, fiberglass, alumina filled matrices can withstand, at best, a total absorbed dose of a few times 1010 rads. Therefore, a coil fabrication and insulating method depending entirely upon inorganic materials was developed. The coils are fabricated from hollow aluminum conductor which is wound, hard anodized, and assembled. Hard anodized aluminum sheets serve as additional layer to layer and ground insulation and inorganically bound mica mat is used between turns.