Mgnetic shear effects on confinement and electron heat transport in tore supra discharges with electron heating

摘要

Various steady state non-inductive plasma, with strong electron heating and sig- nificant modification of the current density profile, have been routinely obtained in Tore Supra discharges with lower hybrid drive(LHCD)and/or fast wave electron heating(FWEH) experiments. The dependence of the electron heat diffusivityχ_e on the electron temperature gra- dient T_e, the magnetic shear s and the safety factor q is demonstrated. The increase ofχ_e with T_e indicates the existence of a critical temperature gradient. Moreover, the current density pro- File affects the global confinement and the local transport.