ELECTROMAGNETIC ANALYSES OF THE GEM DETECTOR MAGNET SYSTEM FOR SSC

The magnet system for the Superconducting Super Collider (SSC) Gamma, Electrons and Muons (GEM) detector consists of a single layer, superco nducting, split solenoid and two iron forward field shapers (FFS). In addition, major structural components, such as the central detector an d FFS support structures and the vacuum vessels, are to be built with magnetic steel. This paper presents the nonlinear, two and three-dimen sional electromagnetic analyses which are performed in support of the overall design effort. A detailed axisymmetric, finite element ANSYS m odel is used to determine the magnetic field distribution in the regio n of the detector, and the electromagnetic forces acting on the coil a nd various magnetic steel elements. A 3-D model is developed to captur e the magnetic field perturbations produced by asymmetric, magnetic st ructural elements. The model produces 3-D field maps of the detector v olume to evaluate the effects of these asymmetries on the detector res olution. Another 3-D model is used to determine the distribution of ma gnetic steel plates required to shield the nearby Electronic Rack Room from the coil's fringe field.