Neutrino Discovery - Experimentally

The detector used by Cowan and Reines

  • In 1953,  neutrinos were experimentally discovered by American physicists Clyde Cowan and Fred Reines.
  • They reasoned that if neutrinos were being created in nuclear processes like beta decay, then placing a detector near a nuclear reactor (huge neutrino source) would be their best chanc
  • The pair relied upon another type of beta decay where an antineutrino (an antimatter neutrino) hits a proton inside one of the atoms in the detector liquid and changes into a neutron and a positron (an antimatter electron).
  • The energy released was unique to this process, therefore the detection of such an amount of energy was seen as a signature for the neutrino.

Antineutrino + Proton → Neutron + Positron. Note the bar above
the neutrino, symbolizing that it is an antimatter particle.