The ${}_{}{}^9{}_{}{}^{}\mathrm{Be}$(${}_{}{}^3{}_{}{}^{}\mathrm{He}$,$\alpha \alpha$)${}_{}{}^4{}_{}{}^{}\mathrm{He}$ reaction has been studied at low incident energy to test the predictions of the pole approximation. Treiman-Yang distributions have been deduced from the measured differential cross sections for a wide range of the Treiman-Yang angle and of the spectator momentum. The data are consistent with the isotropic distribution predicted by the pole mechanism.

NUCLEAR REACTIONS ${}_{}{}^9{}_{}{}^{}\mathrm{Be}$(${}_{}{}^3{}_{}{}^{}\mathrm{He}$,$\alpha \alpha$)${}_{}{}^4{}_{}{}^{}\mathrm{He}$, $E_{{}_{}{}^3{}_{}{}^{}\mathrm{He}}=2.8\mathrm{}$ MeV; measured $\frac{d^3\sigma }{d{\Omega }_{1}d{\Omega }_{2}d{E}_1}$; deduced Treiman-Yang distributions.

• Received 26 March 1981

DOI:https://doi.org/10.1103/PhysRevC.24.1394