Question

Why are γ-radiations emitted during α-emission?

Answer 1

After an alpha emission, the daughter nuclide is often left in an excited state, i.e., it possesses more energy than is required to hold its nucleons together. To become stable, this excited nucleus releases its excess energy in the form of gamma (γ) radiation.

Since gamma rays carry no mass and no charge, the mass number and atomic number of the nucleus remain unchanged; only its energy decreases.