Gamma Decay

In gamma decay,  a nucleus changes from a higher energy state to a lower energy state through the emission of  electromagnetic radiation (photons). The number of protons (and neutrons) in the nucleus does not  change in this  process, so  the parent and daughter atoms  are  the  same  chemical element.  In  the  gamma  decay  of  a nucleus, the emitted photon and recoiling nucleus each have a well-defined energy after the decay. The characteristic energy is divided between only two particles.