Plasma and Fusion Research
Volume 14, 3405162 (2019)
Regular Articles
- Nagoya University, Nagoya 464-8603, Japan
- 1)
- National Institute for Fusion Science, National Institutes of Natural Sciences, Toki 509-5292, Japan
- 2)
- SOKENDAI (The Graduate University for Advanced Studies), Toki 509-5292, Japan
Abstract
In the Large Helical Device (LHD) of the National Institute for Fusion Science, a deuterium plasma experiment was performed in March 2017. Neutrons with an energy of 2.45 MeV are generated by d (d, n) 3He reactions. The evaluation of this neutron flux in the torus hall, as well as within the LHD vessel, is very important for the decommissioning of the LHD in the future and the radiation shielding for workers and components around the LHD. In this study, we evaluate the spatial distribution of thermal and epithermal neutron flux on the floor level of the LHD torus hall by measuring the neutron activation of gold foils. The flux information obtained in the experiment can be used for the evaluation of radio-activation and the shielding design.
Keywords
LHD, neutronics, activation foil, IP, HPGe
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