The Jiangmen Underground Neutrino Observatory (JUNO) is a medium baseline[2][3] reactor neutrino experiment under construction at Kaiping, Jiangmen in Guangdong province in Southern China. It aims to determine the neutrino mass hierarchy and perform precision measurements of the Pontecorvo–Maki–Nakagawa–Sakata matrix elements. It will build on the mixing parameter results of many previous experiments. The collaboration was formed in July 2014[4] and construction began January 10, 2015.[5] Funding is provided by a collaboration of international institutions. Originally scheduled to begin taking data in 2023,[6] as of October 2024, the US$376 million JUNO facility is slated to come online in the latter half of 2025.[7][8][9]
Planned as a follow-on to the Daya Bay Reactor Neutrino Experiment, it was originally to be sited in the same area, but the construction of a third nuclear reactor (the Lufeng Nuclear Power Plant) in that region would disrupt the experiment, which depends on maintaining a fixed distance to nearby nuclear reactors.[10]: 9 Instead it was moved west to a site (Jingji town, Kaiping, Jiangmen)[5] located 53 km from both of the Yangjiang and Taishan nuclear power plants.[10]: 4
^Stock, Matthias Raphael (December 2023). Status and Prospects of the JUNO Experiment. The 17th International Workshop on Tau Lepton Physics. Louisville, Kentucky. arXiv:2405.07321.