Kamioka ObservatoryICRR, The University of Tokyo

On May 7, 2023, Reynald Pain, Director of the French National Institute for Nuclear Physics and Particle Physics (IN2P3), Laurent Vacavant, Scientific Director of IN2P3, Ursula Bassler, Scientific Director of IN2P3, Jacques Maleval, Director of the Regional Office Japan-South Korea-Taiwan of the French National Center for Scientific Research (CNRS), and Benjamin Quilain, Hyper-Kamiokande IN2P3 PI, visited the Hyper-Kamiokande construction site in Kamioka-town, Hida-city, Gifu, Japan. They visited the large cavern where the Hyper-Kamiokande detector will be installed, and the cavern for the water purification system, which is being excavated for the start of the experiment in 2027. Masato Shiozawa, Director of Kamioka Observatory, ICRR, the University of Tokyo, and Yoichi Asaoka, Project Associate Professor (ICRR), explained the current construction status and future plans.

After that, Christophe Bronner, Project Assistant Professor (ICRR), Guillaume Pronost, Research Associate (ILANCE), and Takuya Tashiro, Project Assistant Professor (ICRR), introduced the status of performance evaluation tests of photo-sensors which will be used in Hyper-Kamiokande. They also visited the Hida space and science museum KamiokaLAB and enjoyed the exhibits on the Super-Kamiokande and neutrinos with a guide by the staff.

On May 8, they visited the Institute for Cosmic Ray Research (ICRR) in Kashiwa-city, Chiba. They had a meeting with Masayuki Nakahata, Director of ICRR, Professor Takaaki Kajita, Masato Shiozawa, Director of Kamioka Observatory, Yoshinari Hayato, Associate Professor (ICRR), and Katsuki Hiraide, Project Associate Professor. The IN2P3 side reported on their activity status and confirmed that they would continue to cooperate in promoting the Hyper-Kamiokande experiment.