A cikin 1962 Leon M. Lederman, Melvin Schwartz da Jack Steinberger sun tabbatar ta hanyar yin gwaji a Brookhaven National Laboratory cewa akwai nau'ikan neutrino fiye da ɗaya ta hanyar fara gano ma'amala na muon neutrino (wanda aka riga aka ɗauka tare da sunan neutretto), wanda ya ba su lambar yabo ta Nobel ta 1988. Tambaya: yaushe aka kafa gwajin?
Shekara ta 1962