50th anniversary of neutral current interaction in the Gargamelle bubble chamber (1973)

The discovery of the neutral current was announced in the CERN main auditorium in July 1973. This event shows the real tracks produced in the 1200 litre Gargamelle bubble chamber that provided the first confirmation of a neutral current interaction. A neutrino interacts with an electron, the track of which is seen horizontally, and emerges as a neutrino without producing a muon. It shows an incoming neutrino (not visible) arriving from below where it then interacts with an electron (visible track). The interaction radiates photons and then produces electron–positron pairs.