Dynamical $R$-matrix methodology of Lane and Robson is used to determine the properties of the recently proposed $J^{\pi }=4^{+}$, $\Gamma \approx \mathrm{several}$ MeV, $T=0\mathrm{}$ state at 24.6 MeV excitation energy in the ${}_{}{}^4{}_{}{}^{}\mathrm{He}$ system. The calculations lead to a $J^{\pi }=4^{+}$ state with the following properties: $E_x=42.4\mathrm{}$ MeV, $T=0\mathrm{}$, and $\Gamma =4.0\mathrm{}$ MeV. The model results and data are in reasonable agreement except for predictions of the excitation energy of the $4^{+}$ level. Discrepancies in the excitation energy may be due to model space truncation restrictions, model interaction inadequacies, or uncertainties in the experimental location of the ($4^{+}$,0) level.

NUCLEAR STRUCTURE Calculated via dynamical $R$-matrix methodology the following properties for the proposed ($4^{+}$,0) resonance of Grüebler et al. in ${}_{}{}^4{}_{}{}^{}\mathrm{He}$: $J^{\pi }=4^{+}$, $T=0\mathrm{}$, $\Gamma =4.0\mathrm{}$ MeV, and $E_x=42.4\mathrm{}$ MeV.

• Received 16 December 1982

DOI:https://doi.org/10.1103/PhysRevC.28.2540