我国地下700米有个全球第一！网友：虽然不是很懂，但是大受震撼

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 it as the first operational large-scale and high-precision neutrino-specific scientific facility in the world [1][9] - The initial data collected during the trial operation indicates that the key performance indicators of the JUNO detector have met or exceeded design expectations, enabling it to address a significant issue in particle physics: the ordering of neutrino masses [1][9] Group 1 - The JUNO detector is located 700 meters underground near Jiangmen, Guangdong Province, and can detect neutrinos produced by the Taishan and Yangjiang nuclear power plants, measuring their energy spectrum with unprecedented precision [2] - Unlike similar international experiments, JUNO's measurement of mass ordering is unaffected by terrestrial material effects and other unknown neutrino oscillation parameters, significantly improving the precision of three out of six neutrino oscillation parameters [2] Group 2 - The JUNO project was proposed by the Institute of High Energy Physics, Chinese Academy of Sciences in 2008, received strategic support in 2013, and began construction of the underground laboratory in 2015 [5] - The laboratory construction was completed in December 2021, and the detector installation began, with the infusion of ultra-pure water and liquid scintillator starting in December 2024 [5] - The project team successfully infused over 60,000 tons of ultra-pure water within 45 days, maintaining a liquid level difference within centimeters and a flow deviation of no more than 0.5%, ensuring the safety and stability of the detector structure [5] Group 3 - The core detector of JUNO has an effective mass of 20,000 tons and is located in a 44-meter deep water pool, featuring a stainless steel mesh shell that supports various critical components, including a 35.4-meter diameter acrylic sphere and numerous photomultiplier tubes [7] - The JUNO project is a major international collaboration led by the Institute of High Energy Physics, involving nearly 700 researchers from 74 institutions across 17 countries and regions [9] - The design lifespan of JUNO is 30 years, with potential upgrades to become the world's most sensitive experiment for neutrinoless double beta decay, which could provide insights into fundamental questions about the nature of matter and the universe [9]