Science Bringing Nations Together

Prev | Main | Next

Worldwide Neutrino Web

The idea of an invisible particle that carries off energy was introduced by Wolfgang Pauli in 1930. The term "neutrino" ("little neutral one") was suggested by Enrico Fermi in his 1934 theory of beta-radioactivity which explained how a weak nuclear force could make atomic nuclei unstable. The neutrino, Fermi said, had no mass at all - and John Updike said the same in his 1960 poem, "Cosmic Gall"

"Neutrinos, they are very small. They have no charge and have no mass and do not interact at all…"

But the neutrino does interact, slightly, and its importance has grown under the watchful eyes of experimenters and theorists.

Bruno Pontecorvo first suggested, in 1957 at Dubna, the existence of neutrino oscillations - under the right conditions, different species of neutrinos might be able to interchange roles.

Neutrino theorists Bruno Pontecorvo and Samoil Bilenky at Dubna

In 1962, a group of scientists from Columbia University and Brookhaven National Laboratory performed the first accelerator neutrino experiment and demonstrated the existence of two distinct species, the electron neutrino, and the muon neutrino.

In 1988, Leon Lederman, Mel Schwartz and Jack Steinberger were awarded the Nobel Physics Prize for this discovery.

Neutrino pioneer Jack Steinberger at the Neutrino '90 conference at CERN.

A third species, the tau neutrino, has since been shown to exist.

For many years, neutrinos were believed to have no mass, flashing through the Universe at the speed of light.

Experiments at the Japanese SuperKamiokande laboratory and elsewhere have shown recently that neutrinos probably do have a very tiny mass.

The underground Superkamiokande experiment in Japan uses 22.5 kilotons of water to catch neutrinos.

To be continued

Prev | Main | Next

help | mail | links

Copyright (C) 1996-2000 CERN, JINR. All rights reserved. In case of problems or questions please contact the Webmaster.