Enhancement of the fusion reactivity due to the D-T non-Maxwellian ion distribution and its impact on Lawson criterion

The non-thermal equilibrium, deviating from the Maxwellian distributions is extremely common in magnetically confined fusion plasmas and has a significant impact on fusion reactivity. Our focus in this contribution is on studying reactant particle distribution functions under steady-state conditions. The kinetic framework resolves steady-state Fokker–Planck solutions to characterize non-thermal ion velocity distributions in three distinct heating configurations: Neutral Beam Injection, three-ion species ion cyclotron resonance heating, and alpha particle heating. Numerical simulations indicate that non-Maxwellian distributions can increase fusion reactivity under appropriate parameter conditions while modifying the Lawson criteria thresholds. This study comprehensively analyzes the effects of kinetic modification on fusion reactivity, identifying quantifiable enhancement pathways for energy gain and providing implementable strategies for advanced reactor design.