Lower hybrid power dissipation by tokamak plasma edge electrons

The interaction is studied of TdeV plasma edge electrons with the electric near-field generated by a lower hybrid slow wave antenna. For waveguide electric fields, typically around 3 kV/cm, the higher-order modes overlap, so that the relatively cold (similar to 25 eV) scrape off layer (SOL) electrons can resonantly accelerate. For TdeV conditions and for 90 degrees waveguide array phasing, the stochastic limit in the co-current direction is about 2 keV, determined by the 5(th) harmonic - the last overlapping mode. The progress of electrons through accessible phase space is very efficient: the TdeV 32 waveguide array can accelerate the electrons to the possible limit. We calculate that between 35 and 70 kW is transferred from the wave to the SOL electrons.