Effects of Enhanced Ion/Electron Equilibration Power on CAT-D Tokamak Ignition

The ion to electron temperature ratio (T_i/T_e) is a crucial parameter that affects fusion plasma performance, especially for higher temperature advanced fuel operation. An important factor in the determination of T_i/T_e is the equilibration of energy between ions and electrons. The effect of changes on equilibration rates due to the presence of a magnetic field are considered here. It is found that rates are increased for low beta (∼10%) high temperatures (∼75 keV) Cat-D plasmas, causing a decrease in T_i/T_e and a corresponding increase in nτ_E tor ignition of ∼75%. This effect is less pronounced for high-beta plasmas. Scaling of the changes in equilibration power with macroscopic quantities are presented.