ANALYSIS OF THE EFFECTS OF ELONGATION AND TRIANGULARITY ON THE PROPAGATION OF LOWER-HYBRID WAVES

Lower-hybrid (LH) wave propagation is studied for a general magnetic-field configuration. The ray-tracing equations in the geometric optics approximation are analytically and numerically solved in flux surface coordinates by using asymptotic techniques. In particular, the effects of elongation, triangularity, and the Shafranov shift on wave penetration are pointed out. Numerical applications devoted to the study of current drive generation for the International Thermonuclear Experimental Reactor (ITER) [Nucl. Fusion 31, 1135 (1991)] plasma parameters will also be presented.