Current fast ion collective Thomson scattering diagnostics at TEXTOR and ASDEX Upgrade and ITER plans (invited)

Fast ion physics will play an important role on ITER where confined alpha particles will affect plasma dynamics and overall confinement. Fast ion collective Thomson scattering (CTS) using gyrotrons has the potential to meet the need for measuring the spatially localized velocity distributions of confined fast ions in ITER. Currently, CTS experiments are performed at TEXTOR using a 150kW, 0.2s, 110GHz gyrotron and a receiver upgraded at the Riso National Laboratory. The gyrotron and receiver optics have also been upgraded for rapid scanning during a plasma shot. The receiver consists of a nine-mirror quasioptical transmission line including a universal polarizer and a 42-channel data acquisition system, which allows complete coverage of the double sideband scattered spectrum for localized (∼10cm) time resolved (4ms) measurements of the ion velocity distribution. At ASDEX Upgrade (AUG) a similar 50-channel CTS receiver has been installed. This CTS system will use the 105GHz frequency of a dual frequency gyr...