Development of Merged Compact Toroids for Use as a Magnetized Target Fusion Plasma

Abstract

We report on the development of compact toroid (CT) accelerators to create the target plasma for magnetized target fusion (MTF) devices. Due to the requirements of high initial density of ~10¹⁷ cm⁻³, strong internal fields of 5–10 T, and base temperatures of >100 eV, a design based on conical compression electrodes is an effective avenue to pursue. Progress is being made at General Fusion Inc, (Vancouver, Canada) to develop a pair of large CT accelerators for generating an MTF target plasma. In this design, tungsten coated conical electrodes (with a formation diameter of 1.9 m, a radial compression factor of 4, and overall accelerator length of 5 m) will be used to achieve ohmic heating and acceleration of the CT, yet with low wall sputtering rates. A pair of these accelerators can be synchronized and shot at one another, producing a collision and reconnection of the two CTs within the center of an MTF chamber. Depending on the choice of relative helicities, the two CTs will merge to form either a spheromak-like or an FRC-like plasma.