An Etymological Dictionary of Astronomy and Astrophysics

The transformation of a → radioactive nuclide in which a → beta particle is emitted. In beta minus decay, a → neutron changes into a → proton, → antineutrino, and → electron: n → p + e + ν^-. Beta plus decay involves the conversion of a proton to a neutron, → positron, and → neutrino: p → n + e⁺ + ν.

See also: Beta (β), from → beta particle; → decay.