Other attendees included theorist Venyamin Berezinski cosmic-ray experts Alexander Chudakov, Boris Dolgoshein and Anatolij Petrukhin from Moscow Saburo Miyake (founder of ICRR in Tokyo, later home of Kamiokande) and astronomer G A Tamman. Attendees of the 1976 workshop, showing Fred Reines (back, second from left) and one of the present authors, JL (back, third from left). With light detectors, such as a basketball-sized photomultiplier tube, one could register the light flash over large distances. The water also shields the many downward-moving muons from cosmic-ray interactions in the atmosphere. This detection principle goes back to Russian physicists Moisey Markov and Igor Zheleznykh in 1960: water provides the target for neutrinos, which create charged particles that generate a flash of light in approximate proportion to the neutrino energy. It was at this meeting that the detection of Cherenkov radiation in water was chosen as the most viable method to “see” neutrino interactions in a transparent medium, with some deep lakes and the ocean near Hawaii considered to be good locations. The first organised stirrings of what was to become DUMAND took place at a cosmic-ray conference in Denver, Colorado, in 1973, which led to a preliminary workshop at Western Washington University in 1975. Moreover, totally new concepts such as particle detection via sound waves or radio waves were explored. The technology for smaller water-filled detectors such as IMB (Irvine–Michigan–Brookhaven) and, later, Kamiokande in Japan, were also laid out in detail for the first time. ![]() It was here that some of the first ideas for large detectors such as the gigaton DUMAND (Deep Underwater Muon and Neutrino Detector) array, which eventually morphed into the present-day IceCube experiment at the South Pole, were envisioned. Plans that ultimately would shape the present-day neutrino industry blossomed in September 1976 at a meeting in Waikiki, Hawaii. The time was right to start thinking seriously about neutrino astronomy. Also in the late 1960s, Ray Davis was beginning his famous solar-neutrino observations. The first naturally generated neutrinos, originating from cosmic-ray collisions in the Earth’s atmosphere, were observed in 1965 in deep gold mines located in South Africa and India. On the other hand, the theory of electroweak interactions mediated by the W and Z bosons was firming up, and measurements of neutrinos played a significant role in this context. In 1962, researchers at Brookhaven National Laboratory discovered a second type of neutrino, the muon neutrino, but the third (tau) neutrino would not be seen directly for a further 38 years. Postulated by Pauli in 1930, they had been said to be undetectable due to their tiny interaction probability, and were only first observed in the mid-1950s by Fred Reines and Clyde Cowan using a detector located close to a military nuclear reactor. In 1976, neutrinos did not yet have the prominent role in particle physics that they play today. ![]() A seminal meeting in 1976 shaped the course of neutrino detectors.Ĭover art from the DUMAND conference proceedings, showing the basic undersea neutrino-detection principle.
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