Enhanced confinement regimes at low density and low plasma current with LHCD on FTU
Up to 1 MW of lh waves has been injected in FTU in the density range 0.5 1020 m-3 < <1.5 1020 m-3.
The ratio between the heating power (ohmic +LH) after and before the wave injection is
with POH<=0.2 Plh only at low Ip and low
At low density and low plasma current sawtooth stabilization has been obtained.
In these discharges the energy confinement time is larger than the ITER89-P scaling
It should be noted that the same enhancement is observed with ohmic heating at the transition between linear and saturated regime