Five new research institutes and universities were approved to join the International Collaboration of the Jiangmen Underground Neutrino Observatory (JUNO) on February 17, 2017, bringing the total number of participating institutions to 71, the highest since the collaboration was established.

The applications were reviewed and agreed at the ninth JUNO Collaboration Meeting, which was held at the Zhuhai campus of Sun Yat-sen University from February 13 to 17. More than 170 participants from universities and research institutes in China and about 98 participants from abroad attended the meeting. The new member institutions are Federico Santa María Technical University (Chile), the Centre of Nuclear Studies of Bordeaux-Gradignan (CENBG) (France), Comenius University (Slovakia), the Thailand National Astronomical Research Institute, and Chulalongkorn University Laboratory of Particle Research (Thailand).

Wang Yifang, the project manager, and director of the Institute of High Energy Physics (IHEP), outlined the progress of the experimental project at the meeting. He said that although the civil construction was slightly delayed because of unexpected excessive underground water, design and research on other systems was continuing as planned. Tendering is now complete for the acrylic sphere of the central detector, and a test facility for liquid scintillation purification has started operation at the Daya Bay neutrino experiment site.

Dr. Marcos Dracos, Chairman of the Collaboration board, introduced the new members of the Collaboration, and representatives from each sub-system reported on their latest developments and  plans. The next Collaboration meeting will be held at IHEP in July 2017.