A polarized neutron beam has been used to measure the angular distribution of the analyzing power for the ${}_{}{}^3{}_{}{}^{}\mathrm{He}$($\overrightarrow{\mathrm{n}}$,$\gamma$)${}_{}{}^4{}_{}{}^{}\mathrm{He}$ reaction at $E_n$ $\left(E_x\right)=9.0\mathrm{} \mathrm{}\left(27.3\right)\mathrm{}$ MeV. The angular distribution of the cross section, obtained with an unpolarized beam, is combined with these data to obtain the $b_k$ coefficients. These coefficients are compared to the results of a previous measurement performed for the ${}_{}{}^3{}_{}{}^{}\mathrm{H}$($\overrightarrow{\mathrm{p}}$,$\gamma$)${}_{}{}^4{}_{}{}^{}\mathrm{He}$ reaction, and to the results of a recent continuum shell model calculation.

NUCLEAR REACTIONS ${}_{}{}^3{}_{}{}^{}\mathrm{He}$($\overrightarrow{\mathrm{n}}$,$\gamma$)${}_{}{}^4{}_{}{}^{}\mathrm{He}$, measured $\sigma \left(\theta \right)$ and $A\left(\theta \right)$ at $E_n=9.0\mathrm{}$ MeV. Compared results to previous ${}_{}{}^3{}_{}{}^{}\mathrm{H}$($\overrightarrow{\mathrm{p}}$,$\gamma$)${}_{}{}^4{}_{}{}^{}\mathrm{He}$ measurements and to recent continuum shell model calculations.

• Received 14 December 1981

DOI:https://doi.org/10.1103/PhysRevC.25.2111