A two-step interpretation for the observed analyzing power of ${}_{}{}^{18}{}_{}{}^{}\mathrm{O}$($\overrightarrow{p}$,$t$)${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$($2^{-}$, 8.88 MeV) reaction at 24.4 MeV is reported. The result supports a two-step excitation mechanism for the unnatural-parity state transitions.

NUCLEAR REACTIONS ${}_{}{}^{18}{}_{}{}^{}\mathrm{O}$($\overrightarrow{p}$,$t$) ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$($2^{-}$, 8.88 MeV), $E_p=24.4\mathrm{}$ MeV; calculated $\sigma \left(\theta \right)$ and $A\left(\theta \right)$; second-order DWBA analysis.

• Received 18 September 1978

DOI:https://doi.org/10.1103/PhysRevC.19.2403