Neutrino experiment

The Cowan–Reines neutrino experiment was performed by Clyde L. Cowan and Frederick Reines in 1956. This experiment confirmed the existence of the antineutrino—a neutrally charged subatomic particle with very low mass.

During the 1910s and 1920s, through the study of electron spectra from the nuclear beta decay, it became apparent that, in addition to an electron, another particle with very small mass and with no electric charge is emitted in the beta-decay but not observed. The observed electron energy spectrum was continuous. Assuming energy conservation, this is only possible if the beta decay is a three-body rather than a two-body decay: the latter would produce a monochromatic peak rather than a continuous energy spectrum. This and other reasons led Wolfgang Pauli to postulate the existence of the neutrino in 1930.

Via the inverse beta decay, the predicted electron antineutrino ( ${\bar {\nu }}_{e}$ ${\bar {\nu }}_{e}$ ), should interact with a proton (
p
) to produce a neutron (
n
) and positron ( $e^{+}$ $e^{+}$ ) – the antimatter counterpart of the electron.

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