The `alpha`-decay of nucleus `X^(230)` is accompanied by emission of two groups of `alpha-`particles-one group having `alpha-`particles of kinetic energy 6.7MeV and other having `alpha`-particles of kinetic energy 5.2 MeV. Following the emission of these particles the daugheter muclei are found in ground and exiceted states. find the energy of gamma photon. that is subsequenctly emitted by de-exictation of the excited daughter nuclei. Assume that nuclei of `X^(230)` are at rest.
