Science Talk: JUNO, underground eye on the universe in China

陈小将

Deep beneath Jiangmen, Guangdong province, a monumental scientific instrument is awakening.

The Jiangmen Underground Neutrino Observatory (JUNO) — now in final preparations before its commissioning in August — houses the world's most advanced neutrino detector. At its heart lies a 12-story acrylic sphere containing 20,000 tons of liquid scintillator, shielded by 700 meters of rock and a 44-meter water pool.

This engineering marvel, equipped with 45,000 ultra-sensitive "eyes", which are actually photomultiplier tubes, will achieve an unprecedented 3 percent energy resolution — triple the sensitivity of current detectors.

When neutrinos interact with the scintillator, they emit faint light signals amplified 10 million times. These signals hold keys to fundamental mysteries such as determining which neutrino type is heaviest, simulating stellar explosion mechanisms, and tracing the universe's transformation since the Big Bang.

An international endeavor uniting 700 scientists from 17 countries, including Nobel laureate Arthur McDonald's team, JUNO now forms a neutrino research "trinity" with Japan's Hyper-Kamiokande and America's DUNE, according to the Institute of High Energy Physics, Chinese Academy of Sciences.