A Plan for a Fast-Ion D-Alpha (FIDA) Measurement for JT-60SA∗)
نویسندگان
چکیده
A new fast-ion diagnostic based on the spectroscopy of the Doppler shifted Balmer-alpha line of Deuterium is considered for JT-60SA. Two sight lines, one tangential and the other perpendicular, are examined as candidates. It was found that the tangential one has better sensitivity than the perpendicular one. A trial of the FIDA measurement was performed on JT-60U. Signals due to the tangential-NB injection were obtained. It was found that about the one third of the signal would be due to the active FIDA signal, which was produced by fast-ions and a probe beam, while the remainder would be due to passive signal. The results indicate the FIDA measurement on JT-60SA would be possible with proper background measurements.
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