Impact of Tearing Modes on Electron Temperature Profiles in Tokamaks

Experimental electron temperature profiles are well described by energy transport models that, under reasonable assumptions for the resistivity produce current density profiles stable against tearing modes different from m=2, n=1. A numerical analysis has been performed to see if the observed temperature-current density profiles are intrinsically stable with respect to the tearing modes or if, on the contrary, the tearing modes act as a mechanism that enhances the local transport leading to the observed radial quantities. A steady-state transport model embodying a principle of Delta ' minimization together with an enhanced transport in the vicinity of the rational surfaces q=m/n has been implemented to study the effect of the radial dependence of the electron energy transport on the stability of the tearing modes.