Gamma rays<span> are </span>produced<span> in the disintegration of radioactive atomic nuclei and in the decay of certain subatomic particles. When an unstable atomic nucleus decays into a more stable nucleus, the “daughter” nucleus is sometimes </span>produced<span> in an excited state.</span>
The process of splitting one large nucleus into
smaller ones is nuclear fission.
The process of combining two small nuclei into
one larger one is nuclear fusion.