The marginal stability of experimental profiles

The marginal stability of the ion temperature profiles for both L-mode and supershots is analyzed using a fully implicit δf gyrokinetic code including most relevant kinetic and collisional effects. The stability results tend to indicate that the L-mode discharges are in agreement with the marginal stability hypothesis in the core while the pellet shot is rather well above the critical temperature gradient. The linear stability results are highly inconsistent with the experimentally inferred transport, which implies that effects beyond lowest order ballooning theory must be important