Objectives
Radial profile and energy distribution of fast electrons produced by lower hybrid waves are measured.
[Detectors, Diagnostic Method]
Seven channel sodium-iodide (NaI(Tl)) scintillator-photomultiplier combination is employed to measure the x-ray spectra from 80 keV to 1000 keV.
Detectors are shielded by 23 cm of lead and 50 cm polyethylene to reduce the back-ground gamma-rays.
Specifications
| -Time resolusion | : 50/200 ms (spectra), 1/4 ms (count) [for 12.8/51.2 s] |
| -Energy range | : 80 - 1000 keV |
| -Position | : P-1 section, IN-2A-c port (poloidal array :7 channel) |
| : P-7 section, R-9-c port (counter-tangential :1 channel) | |
| : P-8 section, R-6-e port (co -tangential :1 channel) | |
| -Detector | : NaI(Tl) 5.08 cm in diameter, 5.08 cm in length |
Reference
(1) T.Kondoh et al., "Absorption profile estimation of Lower Hybrid
Waves from the hard x-ray and soft x-ray response", Review of JT-60U experimental results from March to October, 1991, JAERI-M 92-073, 300(1991).
(2) S.Ide et al., "Enhencement of absorption of lower hybrid wave by filling the spectral gap", Physical Review Letters, Vol.73 2312 (1994).