Study of particle and γ decays of the Ex = 12.00 MeV 63+ level in 24Mg

Direct coincidence observation of α- and γ-decays of the E_x = 12.0 MeV level populated in the ${}^{12}\text{C}\text{(}{}^{16}\text{O}\text{, α)}{}^{24}\text{Mg}$ reaction has been used to show that both 6⁺ and 3^? levels exist near this excitation energy. Comparison of the present work with previous radiative capture studies permits the conclusion that the 6₃⁺ level in ²⁴Mg decays primarily by γ-emission, in agreement with recent shell-model calculations using an (sd)⁸ basis. Absolute E2 and M1 strengths deduced from the data are not, however, in good quantitative agreement with the predictions of the shell model.