An elementary particle with a negative charge and a mass 1/1837 that of a proton. Electrons surround the positively charged nucleus of anatom, and determine its chemical properties
U.S. Nuclear Regulatory Commission (NRC), Full-Text Glossary, Washington, DC, USA 2014. http://www.nrc.gov/reading-rm/basic-ref/glossary/f ull-text.html, (Dzstr/ Disabl Mass Care - Amer) {826}
Health Physics Society (HPS), Radiation Terms and Definitions, Virginia, USA 2014. http://hps.org/publicinformation/radterms/#, (Rad Sfty, Prot and Cont - Amer) {825}