The 24Mg(16O,16O') reaction and triaxial structures in 24Mg

Angular distributions for the elastic and inelastic scattering of 16O from 24Mg exciting the 21+ (1.37 MeV), 41+ (4.12 MeV) and 22+ (4.24 MeV) states, have been measured at Esub(c.m.)=43.5 MeV, an energy at which resonance-like structure has been observed previously in the related 24Mg(16O, 12C)28Si reaction. In particular, the 41+, 22+ doublet has been resolved for the first time for heavy-ion projectiles. The data have been well described by coupled-channels calculations within the framework of a Davydov-Filippov asymmetric rotor model for the low-lying states of 24Mg, which has been extended to include a symmetric hexadecapole shape component. The optical model potential for the 16O+24Mg interaction was found to have a moderate real well depth and some surface transparency. The shape parameters for the nuclear potential were determined to be #betta#2sup((N))=0.25, #betta#=220 and #betta#4sup((N))=-0.065 and the corresponding deformation lengths are in good agreement with earlier light-ion results. The inclusion of a negative symmetric hexadecapole component leads to an improved description of the reduced transition rates. The triaxial structure of 24Mg is discussed. (orig.)