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Title: Precise density profile measurements by using a two color YAG/CO{sub 2} laser imaging Interferometer on LHD

Abstract

A multichannel imaging heterodyne interferometer is installed on Large Helical Device. Two branches of the interferometer: one with CO{sub 2} laser (wavelength {lambda}{sub i}=10.6 {mu}m) and other with diode pumped yttritium-aluminium-garnet (YAG) laser (wavelength {lambda}{sub i}=1.06 {mu}m) are used for electron density measurements and vibration compensation. Two slab beams and one circular beam are injected vertically. Liquid nitrogen cooled linear detector arrays are used for detection of slab beams and room temperature detector is employed for single circular beam for CO{sub 2} beams. Avalanche photodiodes record signals for YAG beams. Chordal resolution is from 15 to 22.5 mm, phase resolution is 10{sup -3} of CO{sub 2} fringe, which is determined by the electrical noise of phase counter. About 5x10{sup -3}{approx}10{sup -2} of CO{sub 2} fringe uncompensated signal remains after vibration compensation. Combining existing 13-channels far infrared (wavelength {lambda}{sub i}=119 {mu}m) laser interferometer, profile measurements at high density (>10{sup 20} m{sup -3}) become possible.

Authors:
; ; ; ; ; ; ;  [1]
  1. National Institute for Fusion Science, Toki 509-5962 (Japan)
Publication Date:
OSTI Identifier:
20636645
Resource Type:
Journal Article
Journal Name:
Review of Scientific Instruments
Additional Journal Information:
Journal Volume: 75; Journal Issue: 10; Other Information: DOI: 10.1063/1.1786643; (c) 2004 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0034-6748
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ALUMINIUM; CARBON DIOXIDE LASERS; ELECTRON DENSITY; GARNETS; INTERFEROMETERS; LHD DEVICE; PHOTODIODES; PLASMA DENSITY; PLASMA DIAGNOSTICS; SLABS; STELLARATORS; TEMPERATURE RANGE 0273-0400 K

Citation Formats

Tanaka, K, Sanin, A L, Vyacheslavov, L N, Akiyama, T, Kawahata, K, Tokuzawa, T, Ito, Y, Okajima, S, Budker Institute of Nuclear Physics, 630090, Novosibirsk, Budker Institute of Nuclear Physics, 630090, Novosibirsk, Russia and Novosibirs State University, 630090, Novosibirsk, National Institute for Fusion Science, Toki 509-5962, and Chubu University, Kasugai 487-8501. Precise density profile measurements by using a two color YAG/CO{sub 2} laser imaging Interferometer on LHD. United States: N. p., 2004. Web. doi:10.1063/1.1786643.
Tanaka, K, Sanin, A L, Vyacheslavov, L N, Akiyama, T, Kawahata, K, Tokuzawa, T, Ito, Y, Okajima, S, Budker Institute of Nuclear Physics, 630090, Novosibirsk, Budker Institute of Nuclear Physics, 630090, Novosibirsk, Russia and Novosibirs State University, 630090, Novosibirsk, National Institute for Fusion Science, Toki 509-5962, & Chubu University, Kasugai 487-8501. Precise density profile measurements by using a two color YAG/CO{sub 2} laser imaging Interferometer on LHD. United States. https://doi.org/10.1063/1.1786643
Tanaka, K, Sanin, A L, Vyacheslavov, L N, Akiyama, T, Kawahata, K, Tokuzawa, T, Ito, Y, Okajima, S, Budker Institute of Nuclear Physics, 630090, Novosibirsk, Budker Institute of Nuclear Physics, 630090, Novosibirsk, Russia and Novosibirs State University, 630090, Novosibirsk, National Institute for Fusion Science, Toki 509-5962, and Chubu University, Kasugai 487-8501. 2004. "Precise density profile measurements by using a two color YAG/CO{sub 2} laser imaging Interferometer on LHD". United States. https://doi.org/10.1063/1.1786643.
@article{osti_20636645,
title = {Precise density profile measurements by using a two color YAG/CO{sub 2} laser imaging Interferometer on LHD},
author = {Tanaka, K and Sanin, A L and Vyacheslavov, L N and Akiyama, T and Kawahata, K and Tokuzawa, T and Ito, Y and Okajima, S and Budker Institute of Nuclear Physics, 630090, Novosibirsk and Budker Institute of Nuclear Physics, 630090, Novosibirsk, Russia and Novosibirs State University, 630090, Novosibirsk and National Institute for Fusion Science, Toki 509-5962 and Chubu University, Kasugai 487-8501},
abstractNote = {A multichannel imaging heterodyne interferometer is installed on Large Helical Device. Two branches of the interferometer: one with CO{sub 2} laser (wavelength {lambda}{sub i}=10.6 {mu}m) and other with diode pumped yttritium-aluminium-garnet (YAG) laser (wavelength {lambda}{sub i}=1.06 {mu}m) are used for electron density measurements and vibration compensation. Two slab beams and one circular beam are injected vertically. Liquid nitrogen cooled linear detector arrays are used for detection of slab beams and room temperature detector is employed for single circular beam for CO{sub 2} beams. Avalanche photodiodes record signals for YAG beams. Chordal resolution is from 15 to 22.5 mm, phase resolution is 10{sup -3} of CO{sub 2} fringe, which is determined by the electrical noise of phase counter. About 5x10{sup -3}{approx}10{sup -2} of CO{sub 2} fringe uncompensated signal remains after vibration compensation. Combining existing 13-channels far infrared (wavelength {lambda}{sub i}=119 {mu}m) laser interferometer, profile measurements at high density (>10{sup 20} m{sup -3}) become possible.},
doi = {10.1063/1.1786643},
url = {https://www.osti.gov/biblio/20636645}, journal = {Review of Scientific Instruments},
issn = {0034-6748},
number = 10,
volume = 75,
place = {United States},
year = {Fri Oct 01 00:00:00 EDT 2004},
month = {Fri Oct 01 00:00:00 EDT 2004}
}