China's groundbreaking research on 'ghost particles' marks a significant milestone in its journey to become a global science powerhouse. The country's latest achievement, the Jiangmen Underground Neutrino Observatory (JUNO), has revealed its initial findings, shedding light on the enigmatic neutrinos that permeate our planet yet remain elusive to detection.
The JUNO experiment, a colossal undertaking costing 2.7 billion yuan (US$380 million), has been operational since August, and its results are already making waves. Located in Guangdong province, JUNO comprises a massive underground sphere, 700 meters deep, equipped with over 40,000 light detectors, all designed to capture the elusive neutrino, often referred to as the 'ghost particle'.
Neutrinos, being fundamental particles, are the building blocks of matter, yet they remain largely mysterious. Despite their ubiquity, with trillions passing through the human body every second, scientists still struggle to comprehend their nature. This experiment aims to unravel some of the most profound mysteries in physics by studying these elusive particles.
Major nations, including China, the US, and Europe, have invested substantial resources in such large-scale experiments, attracting top scientific talent and cutting-edge technologies. Professor Wen Liangjian, the physics coordinator at JUNO, highlights a significant achievement: the first set of data from measuring solar neutrino oscillation parameters, which describe the changes in neutrinos traveling from the Sun to Earth, has been measured with unprecedented precision.
Dr. Wang Yifang, leading the China-led international collaboration, expressed satisfaction, stating that JUNO's performance aligns with its design specifications, achieving such precision within just two months of operation. The data collected is shared among participating institutions, fostering collaboration and scientific advancement.
JUNO stands as one of the world's leading facilities in neutrino detection and study, joining the ranks of the Deep Underground Neutrino Experiment (DUNE) in the US and Japan's Hyper-Kamiokande, both still under construction. China's commitment to this research is part of its broader goal of becoming a science and technology powerhouse, emphasizing the importance of basic research in achieving technological independence.
Professor Jennifer Thomas from University College London praised JUNO as 'world-leading,' noting that DUNE and Hyper-Kamiokande are still a few years away from operational status. China's Daya Bay experiment, another neutrino research endeavor, has already made significant contributions to neutrino oscillation measurements, positioning JUNO as a substantial step forward in this field.
Professor Thomas further emphasized the Chinese approach to scientific research, highlighting their focus and willingness to invest substantial funds. She anticipates JUNO to be at the forefront of neutrino oscillation research for the next five years, generating groundbreaking results.
However, Professor J. Pedro Ochoa-Ricoux from the University of California at Irvine, a particle physicist involved in JUNO, clarifies that the US and Japanese facilities are not in direct competition. He explains that while there is some overlap, DUNE and Hyper-Kamiokande address different research questions, and the three experiments are highly complementary, contributing collectively to the advancement of neutrino science.
The JUNO project involves over 700 researchers from 17 countries and regions, including the French National Centre for Scientific Research, one of Europe's largest fundamental science research agencies. Professor Ochoa-Ricoux anticipates JUNO's continued attraction of top scientific minds, given its position at the forefront of neutrino research with a multi-decade physics program.
The acrylic sphere at JUNO contains 20,000 tonnes of a liquid material that emits light flashes when neutrinos collide with atoms. Thousands of light detectors surrounding the sphere capture and measure these light bursts, enabling the detection of neutrinos from nearby nuclear power plants, Yangjiang and Taishan, located 53 kilometers away. The granite mountain beneath the sphere provides shielding against cosmic rays, ensuring accurate measurements.
Professor Oh Choo Hiap from the National University of Singapore's Department of Physics underscores the value of such cutting-edge experiments, stating that they foster the development of new techniques and technologies, which can have future applications. He emphasizes the importance of in-house technical know-how, as it enhances experimental design understanding compared to scientists from other countries or labs not specializing in this area.
