Coil design and economic optimization for multiple mirror fusion reactors

The constraints imposed by design criteria for multiple mirror reactors on minimum-average-B magnet coils are studied. It is found that min-ave-B stabilization of these machines with practical coils is possible. In a typical multiple mirror fusion reactor the min-ave-B coils consist of a superconducting solenoid plus sets of weak quadrupoles placed outside the blanket and shield, and normal, water-cooled mirror strong quadrupole assemblies. Joule losses in mirror strong quadrupole assemblies are studied and found to be important. A new baseball type coil is designed, which reduces these losses considerably. The economic performance of multiple reactors has been studied. 11 refs