In the bowels of the Earth, on the hunt for neutrinos

August 2025 marks a historic milestone for particle physics research: JUNO, the world’s largest underground neutrino detector, has officially begun recording its first data, thanks in no small part to the contribution of the team from the ULB-VUB Interuniversity Institute for High Energy. Here’s a look back at the construction of this giant, nestled beneath the mountains of southern China.

After ten years of design and construction in the mountains of China’s Jiangmen province, JUNO(Jiangmen Underground Neutrino Observatory) is now ready to scrutinize neutrinos - those invisible, almost massless particles that pass through matter without leaving a trace... or almost. This detector will serve the global scientific community for decades to come, ushering in a new era in particle physics and astrophysics.

Since the project’s inception in 2015, ULB’s particle physics department has been at the heart of this international scientific adventure. The IIHE (Institut Interuniversitaire des Hautes Énergies ULB-VUB) team, led by Barbara Clerbaux (Faculty of Science), has developed an essential element of the electronic system: the Backend Cards (BECs), which are part of the experiment’s triggering system and enable the most interesting signals to be identified and recorded. Her involvement doesn’t stop there: she is now working on the analysis of the first signals recorded.

With 20,000 tonnes of glittering liquid and almost 700 researchers from 74 institutions involved, JUNO is an extraordinary scientific project. A true technical and human feat, to which our university is making an active contribution, in order to better unravel the mysteries of the Universe.

See the photos on Better Call Science, the ULB research Instagram account