Review of Experimental Spheromak Research and Future Prospects

A review of experimental spheromak research is presented, together with prospects of near-future experiments and some reactor considerations. In the several experiments based on different schemes, a major effort has recently been made to improve the global magnetohydrodynamic stability and plasma parameters. Electron temperatures sufficiently high to exceed the low-Z radiation barrier have been achieved, and the extensive study of the transport characteristics has begun, aiming to attain more reactor-relevant plasmas with larger current. Finally, an improved conceptual design of a small spheromak reactor is presented, based on a flux injection technique recently developed at the Princeton Plasma Physics Laboratory.