Multistep processes in the 26Mg(p, d) 25Mg reaction at 24.0 MeV

Abstract

Deuteron angular distributions from the 26Mg(p, d) 25Mg reaction at E p = 23.95 MeV and the 25Mg(d, d') 25Mg reaction at E d = 14.96 MeV have been measured with a split-pole magnetic spectrograph. Coupled-channels calculations have been performed to calculate the angular distributions from the inelastic excitation of the 7 2 + and 9 2 + members of the ground-state band (GSB) in 25Mg. The pick-up data have been analyzed with DWBA and CCBA. Two types of deuteron potentials were used in the calculations: an optical-model potential and an adiabatic potential. Only the adiabatic potential yields satisfactory results. The DWBA description of the (p, d) data is not satisfactory — even for the single-particle transitions. Much better results are obtained with CCBA, especially for the ground state and for the heads of both low-lying K π = 1 2 + bands. Reorientation effects appear to be very important both for the shape and the height of the calculated angular distributions. Spectroscopic amplitudes calculated from the Nilsson model do not lead to good descriptions for the states of both low-lying K π = 1 2 + bands — even when band mixing is taken into account. The (p, d; d, d') paths seem to be overestimated in the present calculations for the GSB.