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“beta disintegration”
beta decay, beta disintegration
The radioactive decay of an atomic nucleus accompanied by emission of a beta particle.
Beta decay is the disintegration of the nucleus of an atom to produce a beta particle, or high-speed electron, and an electron-antineutrino.
During beta decay a neutron in the nucleus changes into a proton, thereby increasing the atomic number by one while the mass number stays the same.