ELECTRICAL JOINTS BETWEEN SUPERCONDUCTING COIL MODULES IN THE GEM DETECTOR MAGNET

The GEM Detector magnet at the Superconducting Super Collider is built in two halves each of which is comprised of 12 single layer supercond ucting coil modules wound on a 19 m mean diameter and joined with a lo w resistance lap joint employing the superconducting strands and a cop per stabilizer. Each joint half is attached to the sheathed, cable-in- conduit conductor end, and assembly of the mating halves is completed in the field. The target resistance per joint is 5 x 10(-10) OMEGA at an operating current of 50 kA. Details of the joint design, its coolin g and results of tests on prototypical sub- and full-scale models usin g superconducting strands are presented.