Beta radiation is on of the 3 types of radiactive decay that occur in nature, the others being alpha decay and gamma radiation. Henri Becquerel was awarded the 1906 nobel prize in physics with the Curies for his contribution to the discovery of radioactivity, Becquerel’s discovery being that of beta radiation. This discovery came as an accident to Becquerel whilst experimenting with fluorescence from Uranium. Uranium salts exposed photographic plates wrapped in black paper with an unknown radiation that couldn’t be turned off like X-rays. Ernest Rutherford later continued these experiments to conclude that 2 types of radiation were present, alpha particles (alpha radiation) that didn’t show up as they were absorbed by the paper and beta particles (radiation) that were much more penetrating than alpha particles and able to expose the plate.
We now know the workings of beta radiation and the risks that it can pose to health (unlike at the time of it’s discovery). So, beta decay occurs in one of two ways either as a B+ decay or B- decay of which are determined by the particle that is ejected from the atomic nucleus during the decay process. An unstable nucleus with an excess of neutrons may undergo a B- decay where a neutron is converted into a proton, an electron and an electron type anti neutrino. The proton in this case remains in the nucleus, the electron and anti neutrino are emitted from the nucleus at high speed. A similar situation occurs with B+ decay, in B+ a proton undergoes a conversion to a neutron leading to the emission of a positron (anti particle of the electron) and an electron neutrino.
Beta decay is mediated by the weak nuclear force and as a result weak interaction by causing changes at the quark level (although I won’t go into this). The neutrino is introduced is present in this decay to account for what was initially deemed ‘missing’ energy. In decay a small amount of energy wasn’t present in the decay products this was eventually accounted for by the discovery of the neutrino.
Beta particles although ionising and harmful to health, have their uses to us. They are used to treat a number of eye and bone cancers as well as being used as radioactive tracers. They can also be used in manufacture processes to control the thickness of items coming through a system of rollers, the absorption of particles being correlated to the thickness.