Energy description of wave-plasma interaction in the ion cyclotron range of frequency: Application to fast wave absorption and emission in tokamaks.

An alternative description of the energy transfer between an electromagnetic wave and a tokamak plasma is presented. It involves the evaluation of local coefficients of emission and absorption and leads to rapid numerical procedures. This method allows a coherent description of emission and absorption processes and is thus particularly suited for the determination of the rf electromagnetic energy radiated from the plasma, asis shown by calculating ion cyclotron emission spectra. Furthermore, this ''fluid'' energy description proves also useful for the evaluation of the fast wave plasma absorption during ion cyclotron range of frequency (ICRF) heating: a fast ''fluid'' one-dimensional slab numerical code has been developed. It cannot cope with singularities of the wave vector such as resonance or cutoff, but it is well adapted to scenario designs of fast wave direct coupling to electrons and evaluation of partitioning of energy between species in the case of ions high harmonics. (C) 1997 American Institute of Physics.