Decay, Radioactive 07 : The decrease in the amount of any radioactive material with the passage of time, due to the spontaneous emission from the atomic nuclei of either alpha, beta particles, or gamma rays
28- Radiation Safety Office, Harvard University Department of Environmental Health & Safety, Radiation: Glossary of Terms, Cambridge, MA, USA 2010. radiation_protection@harvard.edu. (Rad Sfty, Prot and Cont - Amer) {82}