The recent Joint European Torus deuterium-tritium campaign has yielded ion-cyclotron-resonanceheated (ICRH) pulses during which both the sawtooth characteristics and the ICRH minority ion population both evolve substantially. At multiple times during each pulse, the evolution of the kinetic-fluid MHD energy is calculated from measurement of the energetic ions and compared with the evolving sawtooth duration. There is strong correlation between sawtooth duration and minority ion stabilization of the ideal internal kink.
