In nuclear physics, a fission reaction that is maintained because neutrons released by the splitting of some atomic nuclei themselves go on to split others, releasing even more neutrons. Such a reaction can be controlled (as in a nuclear reactor) by using moderators to absorb excess neutrons. Uncontrolled, a chain reaction produces a nuclear explosion (as in an atom bomb).
Blue stands for peace. The tassel is a symbol of the monarchy. Yellow represents mineral wealth. Red symbolizes battle. Effective date: 30 October 1967.