First Excited State ofB11and Spin-Flip Stripping

A theoretical treatment is presented of the anomalous angular distribution in the ${\mathrm{B}}^{10}(d, p){\mathrm{B}}^{11}$ reaction to the first excited state of the final nucleus. The experimental distribution is characteristic of the orbital angular momentum of the captured neutron being 1. However, the known spins and parities of the target and final state nuclei do not admit this value. By coupling the spin of the stripped proton to the spin of the target nucleus + neutron, an extra unit of angular momentum may be imparted to this system allowing the final state to be reached. The angular distribution from such a mechanism is calculated and fits rather well the experimental curves.