Bayan bincike, an fahimci cewa muon ba shi da kaddarorin da ake tsammani na meson, amma ya yi kama da lantarki, kawai tare da mafi girma taro. Ya ɗauki har zuwa 1947 don manufar "leptons" a matsayin dangi na barbashi da za a ba da shawara. Neutrino na farko, neutrino na lantarki, wanda Wolfgang Pauli ya gabatar a 1930 don bayyana wasu halaye na lalacewar beta. An fara lura da shi a cikin Cowan Cowan da kuma Cowan Cowan neutrino a shekara ta 1956.
Cowan <unk> Reines neutrino