The ND280 detector, an essential part of the T2K (Tokai to Kamioka) neutrino experiment in Japan, has undergone a significant upgrade to enhance its ability to precisely measure neutrino interactions. T2K aims to study neutrinos to improve our understanding of matter-antimatter asymmetry in the universe.
At the start of its second data collection phase in June 2024, the upgraded near detector ND280, which contains multiple subdetectors assembled and tested at CERN, was used for the first time. This marks the end of an extraordinary journey that started in 2017 as an R&D project between T2K and CERN's Neutrino Platform.
After all the parts arrived in Japan, the detector was tested on the surface before being lowered it into its final position about 50 metres below ground in late 2023. "ND280 passed its first crucial test with flying colours in December 2023," says Stefano Levorato, researcher at INFN. "It was so incredible to see the first event displays with the neutrino tracks."
