Fabrication and Testing of the Magnet System for SuSI Superconducting Source for Ions

A new superconducting ECR ion source operating at 18 + 14.5 GHz microwave frequencies has been designed and is presently being constructed at the National Superconducting Cyclotron Laboratory at Michigan State University. The magnet system consists of a sextupole magnet assembly surrounded by 6 solenoid coils. Using more solenoid coils gives the ability to adjust the minimum magnetic field as well as vary the position of the axial fields at injection and extraction. The sextupole coils are confined within the solenoid bobbin using the inflated bladder technique. Coil winding and individual coil tests have been completed as well as assembly of the magnetic components. Because the sextupole is the most challenging part of the project, due to the high magnetic fields and large forces, each individual coil was tested to current densities well beyond what are required for actual operation. Testing of the completed magnet system was done in a test Dewar prior to completing the LHe vessel and continuing with cryostat construction. Magnet fabrication, assembly, and testing results will be presented.