Plasma confinement by moving multiple mirrors

A major limitation on the energy gain of magnetic mirror fusion machines comes from axial losses through the mirrors. These losses can be dramatically reduced by moving multiple mirror (MMM) sections. A semi-analytical study shows that an MMM section can reduce the axial losses to a level significantly lower than the requirement of the Lawson criterion, using reasonable electrical parameters. A similar analysis is used to design a small scale concept demonstrator which should demonstrate a two-order-of-magnitude reduction in axial losses by an MMM section.