Nuclear states ofSi28andAl28from (α,t) and (α,h) reactions at 80 MeV

Abstract

Angular distributions for the $^{27}\mathrm{Al}(\ensuremath{\alpha},\mathrm{t})^{28}\mathrm{Si}$ and $^{27}\mathrm{Al}(\ensuremath{\alpha},\mathrm{h})^{28}\mathrm{Al}$ one-nucleon transfer reactions have been measured for an incident energy of 80 MeV. Finite-range distorted-wave Born-approximation calculations, using new $\mathrm{sd}$-shell model wave functions, were found to be in reasonable agreement with the data corresponding to exciting positive-parity final states. Transitions to negative-parity ${4}^{\ensuremath{-}}$, ${5}^{\ensuremath{-}}$, and ${6}^{\ensuremath{-}}$ $T=0 \mathrm{and} 1$ states display shapes characteristic of an $l=3$ orbital angular momentum transfer, consistent with a dominant ($0{f}_{\frac{7}{2}}0{d}_{\frac{5}{2}}^{\ensuremath{-}1}$) model configuration. Extracted strengths are in generally fair agreement with previous results, except for those corresponding to the unbound ${5}^{\ensuremath{-}}$ and ${6}^{\ensuremath{-}}$ $T=1$ $^{28}\mathrm{Si}$ states which are about 50% more fragmented than previously observed.