4 0.0005486 amu
ENERGY RELEASE FROM FISSION
Atomic and Nuclear Physics
The total energy released per fission will vary from the fission to the next depending on what
fission products are formed, but the average total energy released per fission of uranium-235
with a thermal neutron is 200 MeV.
As illustrated in the preceding example, the majority of the energy liberated in the fission
process is released immediately after the fission occurs and appears as the kinetic energy of the
fission fragments, kinetic energy of the fission neutrons, and instantaneous gamma rays. The
remaining energy is released over a period of time after the fission occurs and appears as kinetic
energy of the beta, neutrino, and decay gamma rays.
Estimation of Decay Energy
In addition to this instantaneous energy release during the actual fission reaction, there is
additional energy released when the fission fragments decay by emission. This additional
energy is called decay energy, E
. The decay chains for rubidium-93 and cesium-140 are
The energy released during the decay for each chain will be equivalent to the mass difference
between the original fission product and the sum of the final stable nuclide and the beta particles
The energy released in the decay chain of rubidium-93 is calculated below.