Differential cross sections for the reactions ${}_{}{}^{10}{}_{}{}^{}\mathrm{B}(\alpha ,{}_{}{}^6{}_{}{}^{}\mathrm{Li}){}_{}{}^8{}_{}{}^{}\mathrm{Be}_{\mathrm{g}.\mathrm{s}.\mathrm{}}^{}{}_{}{}^{}$ and ${}_{}{}^{10}{}_{}{}^{}\mathrm{B}(\alpha ,{}_{}{}^6{}_{}{}^{}\mathrm{Li}){}_{}{}^8{}_{}{}^{}\mathrm{Be}_{2.9}^{}{}_{}{}^{}$ have been measured in the angular range from 9 to 25° (lab system) in 1° steps at $E_{\alpha }=46\mathrm{}$ MeV. The shapes of the angular distributions are typical of a direct reaction, and the pickup processes are analyzed in distorted-wave approximations on the basis of an extreme cluster model, i.e., on the assumption that a deuteron is picked up from the target nucleus ${}_{}{}^{10}{}_{}{}^{}\mathrm{B}$. Calculations using proper two-particle form factors are also performed, and the results agree with the former method. From the ratio of the experimental to the theoretical cross section, a relative spectroscopic factor (${}_{}{}^8{}_{}{}^{}\mathrm{Be}$-core-plus-deuteron-cluster parentage) is obtained and compared with two-particle fractional-parentage coefficients calculated in intermediate coupling.

• Received 13 July 1970

DOI:https://doi.org/10.1103/PhysRevC.2.1612