Construction of Kamioka Underground Observatory, the predecessor of the present Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo began in 1982 and was completed in April, 1983. The purpose of the observatory was to detect proton decay, one of the most fundamental questions of elementary particle physics. The detector, named KamiokaNDE for Kamioka […]
Neutrino History
1996 – AMANDA neutrino telescope observes neutrinos at the south pole
The Antarctic Muon And Neutrino Detector Array (AMANDA) was a neutrino telescope located beneath the Amundsen-Scott South Pole Station. It consists of optical modules, each containing one photomultipler tube, sunk in Antarctic ice cap at a depth of about 1500 to 1900 meters. In its latest development stage, known as AMANDA-II, AMANDA is made up […]
1995 – Missing solar neutrinos confirmed by GALLEX
Until the year 1990 there was no observation of the initial reaction in the nuclear fusion chain. This changed with the installation of the Gallium Experiments. Gallium as target allows neutrino interaction via νe + 71Ga → 71Ge + e–. The threshold of this reaction is 233 keV (see the spectrum) , low enough also […]
1994 – First proclamation of possible neutrinos oscillations seen by LSND experiment
The Liquid Scintillator Neutrino Detector (LSND) experiment involved the amassed data collected between the years of 1993-1998 designed to measure the number of neutrinos being produced by an accelerator neutrino source. It consisted of a tank filled with 167 tons (50,000 gallons) of mineral oil, 14 pounds of b-PDB (butyl-phenyl-bipheny-oxydiazole) organic scintillator material, and an […]
1991 – LEP experiments show that there are only three light neutrinos
When the LEP collider started operation in 1989 it accelerated the electrons and positrons to a total energy of 45 GeV each to enable production of the Z Boson, which has a mass of approximately 91 GeV. The accelerator was upgraded later to enable production of a pair of W Bosons, each weighing approximately 80 […]
1990 – IMB confirms deficit of muon neutrino interactions
The Atmospheric Neutrino Anomaly IMB found a ratio of ratios equal to (0.54 +/- 0.13) and Kamiokande found a ratio of ratios equal to (0.57 +/- 0.10). This significant difference implies one of two things. Either the simulation is wrong or the standard model prediction of 2:1 muon to electron neutrinos from pion decay is […]
1989 – Kamiokande becomes second experiment detecting neutrinos from the sun and confirms anomaly of finding only 1/3 expected rate
The first evidence of the massive amount of energy produced by supernovas in a neutrino burst came in 1989 when both the Kamiokande and the IMB detected the resulting neutrinos. In 1989 the Kamiokande team confirmed Ray Davis’s 1968 results, that the flux of neutrinos from the Sun was indeed much lower than expected by […]
1987 – Kamiokande and IMB detect simultaneous burst of neutrinos from Supernova
The first evidence of the massive amount of energy produced by supernovas in a neutrino burst came in 1989 when both the Kamiokande and the IMB detected the resulting neutrinos. In 1989 the Kamiokande team confirmed Ray Davis’s 1968 results, that the flux of neutrinos from the Sun was indeed much lower than expected, approximately […]
1985 – The IMB experiment & Russian team reports measurement of non-zero neutrino mass
The IMB experiment, named after the sponsoring organizations: University of California, Irvine, University of Michigan, and the Brookhaven National Laboratory, was a large neutrino observatory consisting of a roughly 20 meter (60 foot) cubical tank full of ultrapure water and layered on the inner surface with 2,048 photomultiplier tubes. Located in a purpose-built cavern in […]
1983 – Kamiokande becomes operational
The original Kamioka Nucleon Decay Experiment, or Kamiokande, was constructed between the years of 1982 and 1983 in Kamiokacho, Gifu, Japan. Located 1000 meters underground and housed in the Mozumi Mine of the Kamioka Mining and Smelting Co., Kamiokande consisted of approximately 1000 photomultiplier tubes or PMTs attached to the inner surface of a tank […]