Researchers using the Super-Kamiokande neutrino detector in Japan have detected the first signal of the Diffuse Supernova Neutrino Background (DSNB), a cumulative flux of neutrinos released by supernovas across billions of years. The detection emerged from analysis of nearly 14 years of data and represents the first observational evidence of this elusive signal, advancing understanding of how massive stars die and seed the universe with heavy elements. The finding could improve knowledge of neutron star and black hole formation in core-collapse supernovas.
Super-Kamiokande, buried 1,000 meters underground, detected the DSNB signal by observing Cherenkov light generated when neutrinos interacted with 50,000 tons of ultrapure water. The signal aligns with theoretical predictions for the DSNB, though it still requires confirmation. The research team plans to combine ongoing Super-Kamiokande observations with data from its planned successor, Hyper-Kamiokande, to increase sensitivity in future studies. Results were presented June 25 at the International Conference on Neutrino Physics and Astrophysics.