Two-step effects in 15-35 MeV proton scattering fromMg24low-lying states

Abstract

Differential cross sections for proton scattering from the six lowest states of $^{24}\mathrm{Mg}$ have been measured at eleven energies from 15 to 35 MeV. Optical model parameters with a constant geometry and with a linear dependence for the well depths have been deduced for the whole energy range. Coupled channel calculations and the asymmetric rotational model describe satisfactorily the inelastic scattering data of the ${K}^{\ensuremath{\pi}}={0}^{+}$ rotational band while, in the fits relative to some members of the ${K}^{\ensuremath{\pi}}={2}^{+}$ band, disagreements have been found. ($p$,$d$,${p}^{\ensuremath{'}}$) and ($p$,${p}^{\ensuremath{'}\ensuremath{'}}$,${p}^{\ensuremath{'}}$) two-step effects have been considered; the contributions to the ${3}_{2}^{+}$(5.22 MeV) level data relative to the last process show an energy dependence in agreement with the $^{24}\mathrm{Mg}$ giant resonance strength distributions.NUCLEAR REACTIONS $^{24}\mathrm{Mg}$($p$,${p}^{\ensuremath{'}}$), ${E}_{p}=15\ensuremath{-}35$ MeV; measured $\ensuremath{\sigma}(\ensuremath{\theta})$ for the six lowest states of $^{24}\mathrm{Mg}$; OM, CC, and CN analyses; deduced OM and deformation parameters; microscopic ADWBA including GR resonance effects and ($p$,$d$,${p}^{\ensuremath{'}}$) two-step analyses of the ${3}_{2}^{+}$ (5.22 MeV) level data. Enriched target.