Scrape-off layer ion temperature measurements at the divertor target in MAST by retarding field energy analyser

Knowledge of the ion temperature (T-i) is of key importance for determining heat fluxes to the divertor and plasma facing components, however data regarding this is limited compared to electron temperature (T-e) data. T-i measurements at the divertor target, between edge-localised modes (inter-ELM) H-mode, have been made using a novel retarding field energy analyser (RFEA). Unlike previous L-mode measurements where T-i = T-e, results from a range of H-mode discharges have shown that at the target T-i/T-e = 1.5-3.The heat flux profiles calculated using these T-i measurements combined with data from the Langmuir probes give a comparison to that measured by infra-red camera. Crown Copyright (C) 2013 Published by Elsevier B. V. All rights reserved.