Phys. Rev. Lett. 83, 3206–3209 (1999)

Fast-Ion Velocity Distributions in JET Measured by Collective Thomson Scattering

H. Bindslev*, J. A. Hoekzema§, J. Egedal¶, J. A. Fessey, T. P. Hughes**, and J. S. Machuzak§ §

JET Joint Undertaking, Abingdon, Oxfordshire, OX14 3EA, United Kingdom

Results on fast ion diagnosis by collective Thomson scattering at JET are presented. 400 kW, 2 mm radiation was scattered in plasmas with energetic proton minority populations heated by 4–8 MW ion cyclotron resonance heating. There is clear evidence of scattering from plasma fluctuations driven by the fast ion population. In a few cases ion velocity distributions with energies in the MeV range could be inferred.