Untitled research work

A review of the procedures which have been developed to measure suprathermal electron distribution functions is given. These experiments have been conducted on three tokamaks; Versator, Tore Supra and TdeV. The absorption of an electron cyclotron wave is measured at frequencies below the fundamental cyclotron frequency. Theory relates this absorption to the amplitude of the distribution function. Experimentally, refractive losses must be separated from absorption losses and contamination of the data by reflections within the system must be avoided. Illustrative results from each tokamak are presented.