A non-local synergism between electron cyclotron waves and lower hybrid waves induced by transport

In this paper, we study the effects of particle radial transport on the ele ctron cyclotron (EC) and lower hybrid (LH) power deposition profiles and cu rrent drive efficiency. We consider a tokamak plasma under the combined act ion of LH waves, EC waves, collisions and spatial transport of electrons ac ross the magnetic surfaces, and consider situations in which the spatial lo cation of the peaks of power deposition profiles for EC and LH waves is not the same. Our results, found from numerical solution of the diffusion equa tion, indicate significant modification in the LH power deposition profile and show evidence of a non-local synergism between LH and EC waves when tra nsport is present, leading to strong enhancing of RF current drive efficien cy.