Measurements of the electron particle diffusion coefficient with the JET multichannel reflectometer

Experimental determinations of the cross-field particle diffusion coefficient (Dp) are important in studies of transport in tokamak plasmas. Dp has been determined from measurements of density perturbations following a sawtooth collapse, oscillating gas puff, and injected high velocity pellets. In each case the density changes have been measured using multichord interferometry and Dp is obtained with an accuracy of typically 20%. In this paper, we present our most recent measurements of Dp. The experimental data are compared with the prediction of a comprehensive numerical transport model which includes both outward going and inward going density pulses. (author) 8 refs., 6 figs