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Related to beta particle: Gamma particle
An electron or positron, especially one emitted at high energy in the decay of certain radioactive nuclei.
(General Physics) a high-speed electron or positron emitted by a nucleus during radioactive decay or nuclear fission
an electron or positron emitted from an atomic nucleus in beta decay.
A high-speed electron emitted by an atomic nucleus undergoing radioactive decay. A beta particle is created when a neutron becomes a proton. Beta particles have greater speed and penetrating power than alpha particles. ♦ The process by which a neutron becomes a proton and emits an electron is called beta decay. Beta decay results in the atomic number of an element being increased by one and its mass number staying the same. See more at radiation, radioactive decay.
An electron emitted by an isotope undergoing radioactive decay.