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The RF-induced pinch of ³He minority ions has been observed in JET affecting the diamagnetic energy, the fast ion energy content, the sawtooth period, the Alfvén eigenmode excitation and the γ-emission. Further, the γ-emission is consistent with RF-detrapping into co-current passing orbits. The results from the SELFO code are consistent with the observations. [ABSTRACT FROM AUTHOR]

The finite drift orbit width, orbit topology and RF-induced transport of resonant ions play an important role in many high power ICRH scenarios in hot plasmas. Wave-particle interactions with waves propagating in the co-current direction produce an inward drift of trapped orbits ultimately detrapping them into passing orbits when the turning points meet. The drift of ions across magnetic flux surfaces gives rise to a torque on the background plasma. Due to the finite orbit width and the finite Doppler shift of the cyclotron resonance, the drifts and hence the torques do not cancel even for toroidally symmetric wave spectra. An inward drift appears near the centre and an outward further out giving rise to a differential acceleration of the plasma. [ABSTRACT FROM AUTHOR]