Charge-exchange measurements of beam ion thermalization in mhd-quiescent plasmas in the poloidal divertor experiment

The horizontally scanning, multi-angle charge-exchange analyser on the Poloidal Divertor Experiment (PDX) was used to study the beam ion slowing-down process with high-power perpendicular injection. Measurements were made over a wide range in toroidal field (8 kG < B_T< 22 kG), plasma current (200 kA < I_p< 500 kA), and beam power (1 MW < P_B< 7 MW). In MHD-quiescent plasmas, agreement is found between the measured slowing-down spectra and theoretical predictions as a function of both angle and energy. Classes of prompt orbit losses are observed with both co- and counter-injection which have been understood and applied to plasma diagnostics.