PROFILE SHAPE PARAMETERIZATION OF JET ELECTRON-TEMPERATURE AND DENSITY PROFILES

The temperature and density profiles of the Joint European Torus (JET) are parametrized using log additive models in the control variables. Predictive error criteria are used to determine which terms in the log linear model to include. The density and temperature profiles are nor malized to their line averages ((n) over bar and (T) over bar). The no rmalized ohmic density shape depends primarily on the parameter (n) ov er bar/B-t, where B-t is the toroidal magnetic field. Both the low mod e (L mode) and the edge localized mode-free (ELM-free) high mode (H mo de) temperature profile shapes depend strongly on the type of heating power, with ion cyclotron resonant heating (ICRH) producing a more pea ked profile than neutral beam injection (NBI). Given the heating type dependence, the L mode temperature shape is nearly independent of the other control variables. The H mode temperature shape broadens as the effective charge, Z(eff), increases. The line average L mode temperatu re scales as B-t(0.96) (power per particle)(0.385). The L mode normali zed density shape depends primarily on the ratio of line average densi ty, (n) over bar, to the edge safety factor, q(95). As (n) over bar/q( 95) increases, the profile shape broadens. The current, I-p, is the mo st important control variable for the normalized H mode density. As th e current increases, the profile broadens and the gradient at the edge sharpens. Increasing the heating power, especially ICRH, or decreasin g the average density, peaks the H mode density profile slightly.