Bounded-plasma theory of radio-frequency heating of toroidal machines

A systematic study is made of the coupling of RF energy to a plasma column by means of an external set of current sources in the toroidal cavity constituted by the machine. The coil loading due to the absorption of RF power by the plasma and by the wall is discussed inside various frequency domains of interest for RF heating. The plasma is described by hot-fluid theory with effective collision frequencies; the latter are either particularized to describe analytically linear collision-less damping or used as parameters to simulate other loss mechanisms like the non-linear ones. Boundary conditions consistent with the magnetic confinement are taken at the plasma-vacuum interface.