Phase-space diagrams for a migma fusion device

Results are presented from a systematic study of three-dimensional orbits in a Migma fusion device. As the vertical oscillation amplitude increases, the frequency of the oscillations decreases rapidly, so that a sequence of nonlinear coupling resonances is encountered. The periodic orbits and vortex boundaries associated with these resonances have been calculated, and the results are displayed in a series of phase-space diagrams, together with an explanation of their significance. The vertical confinement limit and its effect on these diagrams are also described. The problems of beam injection via self-ensnaring are examined, and a special injection orbit is proposed which should provide an exceptionally long confinement time together with a high central density. Finally, the effect of multiple scattering on the ion distribution in phase space is discussed, and arguments are presented in favor of a rather broad distribution under steady-state conditions.