LONGITUDINAL PERMITTIVITY OF A TOKAMAK PLASMA WITH ELLIPTIC AND CIRCULAR MAGNETIC-SURFACES

The contributions of untrapped and three groups of trapped particles t o the longitudinal permittivity of a tokamak plasma with elliptic magn etic surfaces are derived for radio frequency waves in a wide range of frequencies, mode number, and plasma parameters. The analytical expre ssions of the longitudinal permittivity elements are obtained by using the kinetic theory of dielectric tensor elements, where the drift kin etic equation is solved as a boundary-value problem. Considered is a c ollisionless plasma model of an axisymmetric tokamak with small ellipt icity and a large aspect ratio. The limit to the known results for tor oidal plasmas with the circular cross-section of the magnetic surfaces is shown. (C) 1998 American Institute of Physics.