Some Radioactive Decays

Chart showing some well-known radioactive decays: (top to bottom) alpha decay, in which a nucleus emits an alpha particle, which consists of 2 neutrons and 2 protons and is equivalent to a helium nucleus; beta-minus decay, in which an electron is emitted along with an antineutrino (not shown); gamma decay, in which a nucleus gets rid of its excess energy by emitting a gamma ray photon; and proton decay, the release of a single proton from a nucleus. Proton decay is shown from a normal spherically shaped nucleus and from a deformed, football- shaped nucleus. Researchers have found that the rates of proton radioactivity are different for the two types of nuclei because of their different shapes. (Illustration by Malcolm Tarlton, AIP)