China activates giant detector to unlock the secrets of neutrinos

China has taken a groundbreaking step in fundamental particle physics by announcing that JUNO, the world's largest neutrino detector, has become operational. The Institute of High Energy Physics (IHEP) under the Chinese Academy of Sciences (CAS) announced that the project has begun collecting its first measurements.

The massive acrylic sphere, which stands as tall as a 12-story building and has a diameter of 35.4 meters, was constructed 700 meters beneath a granite hill. The detector is positioned at the center of a 44-meter-deep pool of ultrapure water and is filled with 20 thousand tons of a special neutrino-sensitive liquid. This high-tech system detects the oscillations that occur when neutrinos interact with matter.

Known as "ghost particles," neutrinos stand out as one of the most difficult subatomic particles to observe directly to date. The goal of JUNO is to study the transformation movements between these particles—scientifically known as neutrino oscillations—in detail. By analyzing the neutrino flux coming from the nearby Yangjiang and Taishan nuclear power plants, the detector aims to better understand the behavior of these mysterious particles.

According to experts, such research, which proves that there may be mass transfer between neutrinos—previously thought to be massless according to the Standard Model—marks significant turning points in physics. The data that JUNO will collect could play a key role in shedding light on the unknown aspects of neutrinos.

The commissioning of JUNO is a first among the new generation of large-scale neutrino observatories in the world. Meanwhile, the US and Japan are also working on similar experiments. The Deep Underground Neutrino Experiment in the US and the Hyper-Kamiokande Neutrino Observatory in Japan are planned to become operational in 2027-2028.