Measurements of Γ γ/Γ for states of 24Mg in the excitation region 10< Ex< 12MeV

Abstract

Measurements of Γ γ/Γ have been carried out for about 40 states of 24Mg in the excitation region 10 to 12 MeV using a recoil-coincidence technique. The information obtained has been combined with known values of ωγ to determine Γ γ, and Γ α. Widths of the order of 0.01 to 100 eV can be determined accurately using this method. Some previous data on levels in this excitation region are discussed. Excitation energies and electromagnetic transition rates are compared with theoretical predictions. Two notable conclusions are the observation of a considerable excess in E2 strength in the 10 to 12 MeV region compared with that predicted by the shell model, and the identification of the 4 + 11.219 MeV level as possibly being a member of a collective band based on the 0 +, 6.432 MeV level.