Ion Temperature Measurements in the Tore Supra Scrape-Off Layer Using a Retarding Field Analyzer

The retarding field analyzer (RFA) is one of the only widely accepted diagnostics for measuring the ion tem-perature Ti in the tokamak scrape-off layer. An overview of the outstanding RFA performance over ten years of operation in Tore Supra tokamak is given and the validation of Ti measurements is addressed. The RFA measurements in Tore Supra are found to be well reproducible. The ion-to-electron temperature ratio is higher than one at low-to-moderate ion-electron collisionality regime and converges to unity at high collisionality regime (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)