China completes construction of world's largest 'ghost particle' detector
China has successfully completed the construction of the world's largest transparent spherical detector, deep beneath a hill in southern China. The achievement marks a major milestone for the Jiangmen Underground Neutrino Observatory (JUNO). It is a facility dedicated to detecting elusive particles known as neutrinos, often referred to as "ghost particles" due to their elusive nature and role in unraveling cosmic mysteries.
JUNO's neutrino detector: A marvel of scientific engineering
The neutrino detector is a 12-story-tall acrylic sphere with a diameter of 35.4 meters, buried 700 meters underground to protect it from cosmic ray interference. The inside of this giant sphere will be filled with 20,000 tons of liquid that can "flash" when detecting neutrinos. Neutrinos are fundamental particles that carry important information about the universe. They are very tiny, electrically neutral, and travel at almost the speed of light.
Neutrinos: The fundamental building blocks of the universe
Despite their minuscule size, neutrinos are considered fundamental building blocks of the universe and can provide crucial insights into its structure and evolution. "Since the Big Bang, they have permeated the entire universe, generated in various phenomena such as nuclear reactions inside stars, supernova explosions, operation of nuclear reactors and radioactive decay of substances in rocks," an official communique said. However, due to their rare interaction with matter, neutrinos are very difficult to detect.
JUNO's mission and strategic location
JUNO's main objective is to find out the neutrino mass hierarchy, which will revolutionize our understanding of how the universe evolved. The observatory will also study other phenomena like supernovae, atmospheric neutrinos, and solar neutrinos. It is positioned 53km away from both the Yangjiang and Taishan nuclear power plants, enabling the best observation of neutrino oscillation - a phenomenon where neutrinos transform from one type to another.
A collaboration set to revolutionize neutrino research
Launched in 2015, JUNO is a joint project of the Chinese Academy of Sciences (CAS) and the Guangdong government. The project has now entered its final stage, with the facility expected to be fully operational by August 2025. "Once completed, JUNO is expected to capture approximately 40 reactor neutrinos, several atmospheric neutrinos, one geoneutrino and thousands of solar neutrinos every day," an official communique said.
