Neutrinos, often referred to as “ghost particles,” have long posed a challenge to scientists due to their elusive nature. The newly activated Jiangmen Underground Neutrino Observatory (JUNO) in China aims to unravel some of the mysteries surrounding these enigmatic particles. Situated 700 meters beneath the surface, JUNO began its data collection phase recently and is expected to gather insights on between 40 and 60 neutrinos each day over the next 10 years.
Located between the Yangjian and Taishan Nuclear Power Plants, JUNO benefits from the artificial neutrinos produced by these facilities, which adds to the natural neutrinos emitted by the Sun. This strategic positioning ensures that the observatory is surrounded by a high concentration of neutrinos, despite being underground to minimize interference from other particles, such as muons.
To enhance its detection capabilities, JUNO utilizes a sophisticated setup that includes a 44-meter diameter pool of ultrapure water covered by an additional detector known as the “Top Tracker.” This system aims to filter out stray particles that might reach the main detector, which consists of a spherical container filled with a liquid scintillator and surrounded by 43,212 sensitive photodetectors. These photodetectors are designed to capture individual photons, providing crucial data for researchers.
The primary objective of JUNO is to investigate the properties of neutrinos, particularly the three known types: the electron neutrino, muon neutrino, and tau neutrino. Each type exhibits unique characteristics and has the ability to oscillate, or switch between forms. One of the key goals is to determine the mass hierarchy of these neutrinos, establishing which type is the heaviest and which is the lightest.
Researchers also hope to gain insights into the frequency of neutrino oscillation, which could have far-reaching implications across several scientific disciplines. Understanding neutrinos could enhance our knowledge of cosmology, particularly regarding their role in the universe’s early expansion following the Big Bang. Additionally, their properties may shed light on supernovae and even geological processes, as radioactive rocks within the Earth emit neutrinos.
The JUNO project represents a significant collaboration, involving 74 institutes and approximately 700 individuals, and is spearheaded by the Chinese Academy of Sciences’ Institute for High Energy Physics. The observatory is set to operate for at least a decade, during which scientists aim to collect extensive data that will deepen our understanding of these fundamental particles.
As JUNO embarks on this ambitious journey, it holds the promise of advancing multiple fields of science and enhancing our grasp of the universe’s fundamental workings.
