TSC halo disruption-induced forces on the CIT vacuum vessel

Summary form only given. A plasma halo region outside the main plasma has been incorporated in the Tokamak Simulation Code (TSC) so as to allow (force-free) current to flow from a relatively cold (few electronvolts) halo plasma along open field lines and to return through the VV (vacuum vessel). TSC was used to simulate radial disruptions for the CIT (Compact Ignition Tokamak) with plasma halo currents flowing in the VV. The poloidal components of these halo currents, crossed with the toroidal field, produce the dominant VV forces for a 1-ms time period beginning with the thermal quench. For vertical disruptions, poloidal halo currents give net vertical VV forces in the same direction as and of comparable magnitude to the net vertical forces that result from the usual toroidal eddy currents. The influence of the halo temperature and other model parameters on the VV force distributions was studied.