Charge exchange spectroscopy measurements of ion temperature and toroidal rotation in JET
The JET tokamak relies on an active charge exchange spectroscopy diagnostic for measurements of ion temperature, toroidal rotation velocity and impurity density profiles. It uses the neutral heating beams as diagnostic beams and provides measurements at 8 to 12 radial positions simultaneously with a time resolution of about 100 ms. A description of the instrument is given, together with a presentation on the analysis of the experimental data and an account of recent results. Profiles of ion temperature and rotation frequency based on the carbon CVI n=8 to n=7 transition at 5290.5 Å are presented for plasmas in the hot ion mode, for magnetic limiter plasmas, and for discharges where a locked MHD mode brings the plasma to rest despite continued neutral beam injection. H to L-mode transitions are found to cause a collapse of the edge ion temperature and toroidal rotation frequency within a sampling time of less than 12ms. This time resolution is also sufficient to reveal ion heat pulses following sawtooth crashes.
Bibliographic Reference: Report: JET-P(89)48 EN (1989)
Availability: Available from the Publications Officer, JET Joint Undertaking, Abingdon, Oxon. OX14 3EA (UK)
Record Number: 199010425 / Last updated on: 1994-12-01
Original language: en
Available languages: en