Non-Thermal ``Cool'' Fusion Considered for the Ignitor Program

The Ignitor Program [1] has produced the first complete design of a machine capable of approaching ignition regimes with normally known conditions and acceptable safety factors. The ability of high field compact experiments of this kind, that include TRIAM-1 the first high field superconducting machine, to produce well confined plasmas with a wide range of collisionalities, is shown to be suitable also at accessing a variety of interesting physical regimes. These can involve “cool fusion” processes that have been identified theoretically and would allow approaching ignition under milder conditions than those based on the properties of thermonuclear plasmas. A special case is that where the excitation of radially “captive” ballooning modes can provide an efficient energy transfer from reaction products to the tails of the distributions in phase space of the fusing nuclei. The superconducting MgB2 technology that Ignitor has pioneered for the equilibrium coils remains adopted with recent advances. A collaboration with CNR laboratories on near term high field superconducting magnets is undertaken and connects to relevant European research and industrial institutions.

[1] B. Coppi et al., Nucl. Fusion 55, 053011 (2015).