PPPL-3452 is available in pdf or postscript formats.

Fast Ion Loss Diagnostic Plans for NSTX

Authors: D.S. Darrow, R. Bell, D.W. Johnson, H. Kugel, J.R. Wilson, F.E. Cecil, R. Maingi, A. Krasilnikov, and A. Alekseyev

Date of PPPL Report: June 2000

Published in: Rev. Sci. Instrum. 72 (January 2001) 784-787. (Note: Title changed to "Fast Ion Loss Diagnostic Plans for the National Spherical Torus Experiment.")

The prompt loss of neutral beam ions from the National Spherical Torus Experiment (NSTX) is expected to be between 12% and 42% of the total 5 MW of beam power. There may, in addition, be losses of fast ions arising from high harmonic fast wave (HHFW) heating. Most of the lost ions will strike the HHFW antenna or the neutral beam dump. To measure these losses in the 2000 experimental campaign, thermocouples in the antenna, several infrared camera views, and a Faraday cup lost ion probe will be employed. The probe will measure loss of fast ions with E>1 keV at three radial locations, giving the scrape-off length of the fast ions.