Name for the former unit of activity. The activity of 1 curie, symbol: Ci, is equal to the decay of 3.7·1010 (37 billion) atoms of a radionuclide per second. The activity unit curie was replaced by → Becquerel. 1 curie = 3.7·1010 becquerels
Winfried Koelzer, Nuclear Terms, Karlsruher Institut for Technologie KIT (Ed.), ISBN German print version 2001: 3-923704-32-1, Translation by Informationskreis KernEnergie (Berlin), Karlsruhe, Germany 2013. https://www.euronuclear.org/info/encyclopedia/pdf/ Nuclear_Glossary-%202013-02-13.pdf, (Nucl Sfty - Amer) {1011}