Nucleus 09 : The small, central region of an atom consisting of protons and neutrons (nucleons). The nucleus contains essentially all of the mass of the atom
Jefferson Lab, Radiation Worker Glossary, Newport News, VA, USA 2007. http://www.jlab.org/div_dept/train/rad_guide/gloss ary.html, (Rad Sfty, Prot and Cont - Amer) {1005}