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The RF power partition and power deposition on resonant ion species during ICRH depend strongly on the distribution functions of the heated ions. The distribution functions in turn depend on RF interactions and Coulomb collisions with the background plasma. It has previously been found that the finite ion orbit width, as well as the RF induced transport of resonant ions, are important for describing the distribution functions. This is particularly important in ITB plasmas, where low central current density results in broad orbits. To simulate ICRH in ITB plasmas the SELFO code has been upgraded to self-consistently calculate the wave field and the distribution functions of several ion species, including beam injected ions. Simulations of hydrogen minority heating of a deuterium, JET-like, ITB plasma have been made for different antenna phasings, with and without NBI. The distribution functions of both hydrogen and deuterium have been simulated. Finite orbit width and RF induced particle transport effects are shown to have a large impact on the partition of RF power absorption between hydrogen and deuterium, and thereby on the power transfer to the background. [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]