NEUTRINO OSCILLATIONS FOR THE FIRST TIME
To examine numerous physics events, the Super-Kamiokande experiment in Japan used a giant subterranean detector filled with ultrapure water. The first evidence of neutrino oscillations was revealed by the team in 1998, implying that neutrinos must have mass (something Bruno Pontecorvo had suggested decades before). Some air muon neutrinos vanished as they went to the one-kilometer-deep detector, oscillating into a different flavor, according to the experiment.
