We have employed the line shape analysis technique to study nuclear spin alignment produced in the ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ + ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ reaction populating the $2^{+}$ 4.43-MeV state in ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$. We present excitation functions of $m$-substate population $P\left(m\right)\mathrm{}$ measured in the range $E_{\mathrm{c}.\mathrm{m}.\mathrm{}}=19\mathrm{}-22.6$ MeV and detailed angular distributions of $P\left(m\right)\mathrm{}$ obtained at $E_{\mathrm{c}.\mathrm{m}.\mathrm{}}=21.7,21.9, \mathrm{and} 22.3$ MeV. Results have been analyzed in terms of a single resonance with sharp spin in the compound nucleus and found to contradict previous spin assignment based on studies of angular distributions of cross section in the $E_{\mathrm{c}.\mathrm{m}.\mathrm{}}\approx 22 \mathrm{to} 22.6$ MeV region.

NUCLEAR REACTIONS ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$(${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$, ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}_{}^{*}{}_{}{}^{}$)${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$, $E_{\mathrm{lab}}=45\mathrm{}-53$ MeV. Measured $\sigma (E;E{}_{}{}^{12}{}_{}{}^{}\mathrm{C}_{}^{*}{}_{}{}^{},\theta )$, deduced ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}_{}^{*}{}_{}{}^{}$ (4.43 MeV, $2^{+}$) spin alignment ($\sigma (E;m,\theta )$). ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ + ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ resonances, deduced $J$, $\pi$.

• Received 18 April 1979

DOI:https://doi.org/10.1103/PhysRevC.21.167