Binding Energy per Nucleon
The nuclear binding energy divided by the number of nucleons, measuring the stability of a nucleus.
Formula / equation
BE/A
Unit
MeV/nucleon
In depth
Plotted against mass number, the curve rises steeply to a maximum near iron-56 at about 8.8 MeV and then declines slowly. Nuclei move towards that peak when they react, which is why light nuclei release energy by fusing and heavy nuclei by splitting.
Examples in the real world
Iron-56 sits at the peak, which is why it is the end point of stellar nucleosynthesis in massive stars.