The following is a short history of neutrinos as it relates to neutrino oscillation studies.

1920-1927 Charles Drummond Ellis (along with James Chadwick and colleagues) establishes clearly that the beta decay spectrum is really continuous, ending all controversies.

1930 Wolfgang Pauli hypothesizes the existence of neutrinos to account for the beta decay energy conservation crisis.

1932 James Chadwick discovers the neutron.

1933 Enrico Fermi writes down the correct theory for beta decay, incorporating the neutrino.

1946 Shoichi Sakata and Takesi Inoue propose the pi-mu scheme with a neutrino to accompany muon.

1956 Fred Reines and Clyde Cowan discover (electron anti-) neutrinos using a nuclear reactor.

1957 Neutrinos found to be left handed by Goldhaber, Grodzins and Sunyar.

1957 Bruno Pontecorvo proposes neutrino-antineutrino oscillations analogously to K0-K0bar, this is the first time neutrino oscillations (of some sort) are hypothesized.

1962 Ziro Maki, Masami Nakagawa and Sakata introduce neutrino flavor mixing and flavor oscillations.

1962 Muon neutrinos are discovered by Leon Lederman, Mel Schwartz, Jack Steinberger and colleagues at Brookhaven National Laboratories and it is confirmed that they are different from electron neutrinos.

1964 John Bahcall and Ray Davis discuss the feasibility of measuring neutrinos from the sun.

1965 The first natural neutrinos are observed by Reines and colleagues in a gold mine in South Africa, and by Goku Menon and colleagues in Kolar gold fields in India, setting first astrophysical limits.

1968 Ray Davis and colleagues get first radiochemical solar neutrino results using cleaning fluid in the Homestake Mine in North Dakota, leading to the observed deficit now known as the "solar neutrino problem".

1976 The tau lepton is discovered by Martin Perl and colleagues at SLAC in Stanford, California.  After several years, analysis of tau decay modes leads to the conclusion that tau is accompanied  by its own neutrino, nutau, which is neither nue nor numu.

1980s The IMB, the first massive underground nucleon decay search instrument and neutrino detector is built in a 2000' deep Morton Salt mine near Cleveland, Ohio. The Kamioka experiment is built in a zinc mine in Japan.

1985 The "atmospheric neutrino anomaly" is observed by IMB and Kamiokande.

1986 Kamiokande group makes first directional counting observation solar of solar neutrinos and confirms deficit.

1987 The Kamiokande and IMB experiments detect burst of neutrinos from Supernova 1987A, heralding the birth of neutrino astronomy, and setting many limits on neutrino properties, such as mass.

1988 Lederman, Schwartz and Steinberger awarded the Physics Nobel Prize for the discovery of the muon neutrino.

1989 The LEP accelerator experiments in Switzerland and the SLC at SLAC (Stanford) determine that there are only 3 light neutrino species (electron, muon and tau).

1991-2 SAGE (in Russia) and GALLEX (in Italy) confirm the solar neutrino deficit in radiochemical experiments.

1995 Frederick Reines and Martin Perl share the Physics Nobel Prize for discovery of electron neutrinos (and observation of supernove neutrinos) and the tau lepton, respectively.

1996 Super-Kamiokande, the largest particle detector ever, begins searching for neutrino interactions on 1 April at the site of the Kamioka experiment, with a Japan-US team.

1998 After analyzing more than 500 days of data, the Super-Kamiokande team reports finding oscillations in atmospheric neutrinos and, thus, neutrino mass.

1999-2000 The Chooz and Palo Verde reactor experiments report no oscillations, concluding that electron neutrinos are not the dominant participant in the atmospheric neutrino oscillations.

2000 The DONUT Collaboration working at Fermilab announces observation of tau particles produced by tau neutrinos, making the first direct observation of the tau neutrino.

2000 Super-Kamiokande announces that the oscillating partner to the muon neutrino is not a sterile neutrino, but the tau neutrino.

2001-02 SNO announces observation of neutral currents from solar neutrinos, along with charged currents and elastic scatters, providing convincing evidence that neutrino oscillations are the cause of the solar neutrino problem.

2002 Masatoshi Koshiba and Raymond Davis win Nobel Prize for measuring solar neutrinos (as well as supernova neutrinos).

2002 KamLAND observes neutrino oscillations consistent with the solar neutrino puzzle using, for the first time, man-made neutrinos.

Modified by Giorgio Gratta from an original by John Leaned and Sandip Pakvasa.

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