探寻地下700米的粒子世界

Core Insights - The Jiangmen Underground Neutrino Observatory (JUNO) has successfully completed the infusion of 20,000 tons of liquid scintillator and has officially begun data collection, marking a historic milestone in neutrino research [1][2] - JUNO is the first large-scale, high-precision neutrino detector in the world, aimed at addressing fundamental questions about the nature of matter and the universe [1][2] - The detector is located 700 meters underground in Jiangmen, Guangdong Province, and can detect neutrinos from nuclear power plants located 53 kilometers away, measuring their energy spectrum with unprecedented precision [1][2] Technical Details - JUNO's design allows for the measurement of neutrino mass ordering without being affected by terrestrial matter effects and other unknown neutrino oscillation parameters, significantly improving the precision of three out of six neutrino oscillation parameters [2] - The core of the JUNO detector consists of a 20,000-ton liquid scintillator housed in an organic glass sphere, surrounded by thousands of photomultiplier tubes that detect faint light signals produced when neutrinos interact [2] - The construction of JUNO involved extensive planning, testing, and collaboration among hundreds of engineers and technicians, ensuring strict requirements for material purity, stability, and safety [2] Collaborative Efforts - JUNO is a major international collaboration led by the Institute of High Energy Physics of the Chinese Academy of Sciences, involving approximately 700 researchers from 74 institutions across 17 countries and regions [3] - The success of JUNO is attributed to effective international cooperation, which brought expertise in liquid scintillator detection technology to the project, pushing the boundaries of this technology [3] - The design lifespan of JUNO is planned for 30 years, with potential upgrades to become the world's most sensitive experiment for neutrinoless double beta decay, aiming to measure the absolute mass of neutrinos and investigate whether neutrinos are Majorana particles [3]