China is one step closer to measuring the mysterious neutrino particle after installing a giant underground spherical detector in Guangdong province.
The sphere is about 35 m in diameter and is the central part of the Jiangmen Underground Neutrino Observatory (Juno), a project in Jiangmen city, Guangdong province. The sphere will contain about 20,000 tons of scintillator and be suspended in 35,000 tons of pure water 700 meters underground to measure the mass of different types of neutrinos produced by two nearby nuclear power plants , MSN reported on October 13.
Nicknamed “ghost particles”, neutrinos are elementary particles that are difficult to detect because they have no electrical charge, have very little mass, and move at speeds close to the speed of light. Although nearly all particles pass through the liquid medium without leaving a trace, some interact with the liquid, creating two flashes of light that can be detected by thousands of light detectors.
According to CCTV, the sphere has been installed and engineers are assembling its outer metal shell and optical tube. Installation is expected to be completed by the end of November and the facility will begin collecting data from August next year. Previously, data collection was scheduled for 2023.
Construction of the laboratory began in 2015, but the project was delayed due to groundwater problems. This is an international project with a team of 750 researchers from 74 institutes in 17 countries and territories, nearly 300 of which are from Europe, including Italy, Germany and France.
Juno is a follow-up project to the Daya Bay Reactor Neutrino Experiment, which operated from 2003 to 2020 near Shenzhen, Guangdong province. American scientists participated in the Daya Bay project but did not collaborate on the Juno project. As expected, Juno will be the first machine to operate among the new generation of neutrino detectors around the world.
Both the Deep Underground Neutrino Experiment in the US and the Hyper – Kamiokande observatory in Japan are scheduled to be inaugurated and operational around 2027 – 2028. According to Wang Yifang, director of the Institute of High Energy Physics (IHEP) of the Chinese Academy of Sciences, the team of experts has developed many technologies to upgrade Juno, including the world’s most efficient light detector optical tube. All results obtained during the construction and future operation of Juno will be published by the international cooperation group. It will take Juno 5-6 years to collect a total of 100,000 signals to resolve the question of neutrino mass.