Nuclear fusion : In stars energy is produced by hydrogen into helium.
Fission in a nuclear reactor : In nuclear reactor fission of ${}_{92}{}^{235}\mathrm{U}$ takes place by absorption of thermal neutrons. Heavy water is used as a moderator during this reaction.
${}_{27}{}^{60}\mathrm{C}\mathrm{o}$ emits $\mathrm{\beta }$ particle to attain stable nucleus. It also emits $\mathrm{\gamma }$ radians.
$\mathrm{\gamma }$ -rays are emitted by ${}_{27}{}^{60}\mathrm{C}\mathrm{o}$ during fission of ${}_{92}{}^{235}\mathrm{U}$ , conversion of hydrogen to helium and during decay of ${\mathrm{U}}^{235}$ after absorption of neutron.