Received the Fujimori Award for Technology from the Rare Earth Society of Japan

Received the Fujimori Award for Technology from the Rare Earth Society of Japan
Development of low-radioactive gadolinium sulfate for Super-Kamiokande

Our company's Yasuhide Yamaguchi and Yuta Tanaka received the 27th Technology Award (Fujimori Award) from the Rare Earth Society of Japan on May 30, 2023 for their research achievement in "Development of Low Radioactive Gadolinium Sulfate for Super-Kamiokande. The Fujimori Prize is a very prestigious award given to individuals or groups that have made significant contributions to the development of rare earth technology and its advancement.

Super-Kamiokande needed extremely pure gadolinium sulfate in order to observe neutrinos with higher sensitivity. This is because the light sensor installed in Super-Kamiokande is very sensitive and detects the noise if radioactive impurities are present.
Radioactive elements, especially thorium in ppt^{note (supplementary information) symbol}We have been studying how to stably mass-produce gadolinium sulfate with a reduced level of gadolinium sulfate, and have succeeded in continuous production at high purity by combining NYC's proprietary technology of solvent extraction and other methods. It took four years from development to completion of the treatment flow, followed by three years of production, and 39 tons of gadolinium sulfate was delivered to Super-Kamiokande.
The total dissolution and injection of gadolinium sulfate was completed in August 2022, and observations began at the end of last year. The introduction of low-radioactive gadolinium sulfate is expected to improve the sensitivity of neutrino observations, especially the world's first observation of "supernova background neutrinos.
For a detailed explanation of the purpose and effects of adding gadolinium to Super-Kamiokande, please visit the University of Tokyo Institute for Cosmic Ray Research website.

https://www-sk.icrr.u-tokyo.ac.jp/news/detail/422/

*ppt: parts per trillion