High Ion Temperature Mode in Heliotron-E

A high ion temperature T_i mode is observed for neutral beam heated plasmas in Heliotron-E. This high T_i mode plasma is characterized by a peaked ion temperature profile and is associated with a peaked electron density profile produced by neutral beam fueling with low wall recycling. The observed improvement in ion heat transport can be related to the radial electric field shear rather than to the rotation velocity shear in the bulk plasma