1965 Kolar Gold and South Africa experiments : Located in India, in the Kolar Gold Field mine, 7500 m underground, the KGF detector was looking for muons produced by atmospheric neutrinos, resulting from cosmic rays interaction with Earth’s atmosphere. It was made of 3m walls of plastic scintillators, Neon flash tubes and photomultipliers. The experiment discovered the first atmospheric neutrinos about the same time as an other experiment done by F. Reines team in a mine in South Africa. Some of the experimental observations, called Kolar events, have yet to be explained as they suggested the existence of massive particles having a long life time and that interacted with the detector.

Experiments on Neutrinos