Inverse beta decay

Inverse beta decay, commonly abbreviated to IBD, is a nuclear reaction involving electron antineutrino scattering off a proton, creating a positron and a neutron. This process is commonly used in the detection of electron antineutrinos in neutrino detectors, such as the first detection of antineutrinos in the Cowan–Reines neutrino experiment, or in neutrino experiments such as KamLAND, Borexino and SAGE (Soviet–American Gallium Experiment). It is an essential process to experiments involving low energy neutrinos (< 60 MeV) such as those studying neutrino oscillation,reactor neutrinos, sterile neutrinos, and geoneutrinos.

Inverse beta decay proceeds as

${\displaystyle {\bar {\nu }}_{e}+p\to e^{+}+n}$,

...
Wikipedia