Spontaneous fission (SF) is a form of radioactive decay that is found only in very heavy chemical elements. The nuclear binding energy of the elements reaches its maximum at an atomic mass number greater than about 58 atomic mass units (u), spontaneous breakdown into smaller nuclei and a few isolated nuclear particles becomes possible at heavier a...
type of radioactive decay in which certain unstable nuclei of heavier elements split into two nearly equal fragments (nuclei of lighter elements) ... [3 related articles]
nuclear fission which occurs naturally in certain radionuclides
Nuclear decay by splitting the nucleus into two parts (fission fragments), neutrons, and gamma rays. 
Nuclear decay by splitting the nucleus into two parts (fission fragments), neutrons, and gamma rays.