Detection of Antineutrinos / Neutrinos

Since neutrinos do not ionize matter, they cannot be detected directly. The antineutrino detection (1995 Nobel Prize for Frederick Reines and Clyde Cowan) is  based on the reaction:

This interaction is symmetrical to the beta decay of free neutron, therefore it sometimes referred to as inverse beta decay. All detection methods require the neutrinos to carry a minimum threshold energy of 1.8 MeV. Only antineutrinos with an energy above the threshold of 1.8 MeV can cause interactions with the protons in the water, producing positrons and neutrons.


Reference: Griffiths, David, Introduction to Elementary Particles, Wiley, 1987.

antineutrino detection
Antineutrino signature: coincidence between prompt positron and delayes neutron capture on hydrogen.
Source: Slides – Dr. Blucher, Enrico Fermi Institute
Antineutrino detector
The inside of a cylindrical antineutrino detector before being filled with clear liquid scintillator, which reveals antineutrino interactions by the very faint flashes of light they emit. Sensitive photomultiplier tubes line the detector walls, ready to amplify and record the telltale flashes.
Photo: Roy Kaltschmidt, LBNL
Source: Daya Bay Reactor Neutrino Experiment

See above:

Antineutrino

See next:

Nuclear Reactor as the Antineutrino Source