Abstract
The confinement of auxiliary heated NSTX discharges is discussed. The energy confinement time (in
plasmas with either L-mode or H-mode edges) scales favorably compared to ITER97L and ITRE98Pby(2)
scalings, being up to 2-3 times L-mode and 1.5 time H-mode. TRANSP calculations based on the kinetic profile
data reproduce the magnetics-based determination of stored energy and the measured neutron production rate.
Power balance calculations reveal ion thermal transport to be near neoclassical level, and well below the electron
thermal transport, which is the main loss channel. Perturbative impurity injection techniques also indicate the
particle diffusivity to be near the neoclassical level. H-mode operation has been obtained during high-harmonic
fast-wave heating.