Positron emission

Positron emission, also known as positron decay or β⁺ decay, is a type of radioactive decay in which an unstable atomic nucleus emits a positron. A positron is the antimatter counterpart of an electron, possessing the same mass as an electron but with a positive charge. In positron emission, a proton in the nucleus of an atom is transformed into a neutron, accompanied by the release of a positron and a neutrino (an almost massless, neutral particle).