https://doi.org/10.1051/epjconf/202327703008
New Q and V-band ECE radiometer for low magnetic field operation on LHD
1
National Institute for Fusion Science, National Institutes of Natural Sciences, Toki 509-5292, Japan
2
The Graduate University for Advanced Study, SOKENDAI, Toki 509-5292, Japan
3
College of Engineering, Chubu University, Kasugai 487-8501, Japan
4
Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa 277-8561, Japan
* Corresponding author: tokuzawa@nifs.ac.jp
Published online: 23 February 2023
To meet the demand for information on electron temperature fluctuations in low magnetic field experiments in the Large Helical Device (LHD), a new ECE radiometer covering the Q and V bands has been installed. Combination mirrors are installed in the vacuum vessel to focus the beam and efficiently propagate the radiated electron cyclotron waves. Notch filters are used to eliminate stray light from the gyrotron, and a 32-channel heterodyne radiometer is constructed using a filter bank system. As a result, oscillations of electron temperature and both electromagnetic and electrostatic fluctuations were successfully observed.
© The Authors, published by EDP Sciences, 2023
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