Design Considerations for a Migma Advanced Fuel Fusion Reactor

The migma concept is being pursued at Fusion Energy Corporation as a means of achieving controlled fusion.1-4 The features which distinguish this concept from other controlled fusion concepts may be summarized as: 1. High energy 2. Ordered motion 3. Use of advanced fuels 4. Small physical size Beams of ions are injected into the field of a superconducting magnet at MeV energies. The resulting motions of trapped ions have a high degree of order in phase space compared with a thermalized gas. At MeV energies the two major ion loss mechanisms, charge transfer and multiple Coulomb scattering, are greatly suppressed compared with thermonuclear energies (1-100 keV), because the cross section for multiple Coulomb scattering falls off as T1-5 and that for charge transfer approximately as T-5. Because ions are injected at nearly the average energy of the migma, it may also be said that, as a practical matter, the use of ordered motions facilitates the attainment of colliding energies in the MeV range. The ion motion is essentially that of precessing orbits which all intersect within a central core that is small compared with a gyrodiameter. Motion along the magnetic field lines is confined by a non-adiabatic focusing. The high collision energies obtainable enable the use of what are called "Advanced Fuels," that is, fuels other than the deuteriumtritium (D-T) mixture planned for, e.g., the tokamak fusion reactor. These fuels require higher collision energies for useful reaction rates.