Question

Describe gamma decay and write down the formula for the energy generated in this decay.

Answer 1

A given nucleus does not emit α- and -β particles simultaneously. However, on emission of α or β-particles, most nuclei are left in an excited state. A nucleus in an excited state emits a γ-ray photon in a transition to the lower energy state. Hence, α-and β-particle emissions are often accompanied by γ-rays.

\[\ce{_Z^AX->_2^4\alpha{ +} _{Z-2}^{A-4}Y + energy released}\]

\[\ce{_Z^AX->_-1^0\beta{ +} _{Z+1}^{A}Y + energy released}\]

\[\ce{_Z^AX->_0^0\gamma{ +} _{Z}^{A}X}\] (Energy released is carried by the γ-ray photon).