Disappearance of a radioactive substance due to nuclear emission of an α or β particle, capture of an atomic electron, or spontaneous Breaking apart of a body into smaller fragments. In nuclear physics, fission refers to splitting of a heavy atomic nucleus into two or more lighter nuclei with an associated release of energy. The mass of the nucleus before fission is greater than the combined masses of the resulting fragments; the. In rare instances proton, Charge-neutral hadron with a mass of 1.6748 x 10-27 kg, equivalent to 939.573 MeV, and an intrinsic angular momentum, or spin, of ½ (in units of h/2π). The neutron is a nucleon, one of the two basic constituents of all atomic nuclei (apart from 1H, which consists of a single, or light Substance composed of atoms, each of which has the same atomic number (Z) and chemical properties. The chemical properties of an element are determined by the arrangement of the electrons in the various shells (specified by their quantum number) that surround the nucleus. In a neutral atom, the number of (for example 14C) emission can occur. When a large amount of decay energy is available, β-delayed emission of neutrons, protons, and other particles may occur.
Some or all content above used with permission from J. H. Wittke.