Distorted-wave effects in stripping reactions may be more apparent in the analysis of nucleon-$\gamma$-ray angular correlation than in the angular distribution of the stripped nucleon. The reaction ${\mathrm{B}}^{11}(d, n{\gamma }_{15.11\mathrm{MeV}}){\mathrm{C}}^{12}$ has been used to study the distortion effect, since the angular distribution of neutrons feeding 15.11-MeV 1(+) state shows remarkably good agreement with the Butler stripping pattern. The angular distribution of other neutron groups of the reaction ${\mathrm{B}}^{11}(d, n){\mathrm{C}}^{12*}$ cannot be fitted satisfactorily by Butler approximation. The neutrons feeding the 1(+) 15.11-MeV state of ${\mathrm{C}}^{12}$ as determined by a time-of-flight technique were detected in coincidence with the 15.11-MeV de-excitation $\gamma$ ray emitted in direction 10° and 90° relative to the incident deuterons at deuteron energies of 2.59 and 2.29 MeV. The result of the $n-\gamma$ correlation shows marked departure from the plane-wave, Butler theory.

• Received 21 January 1963

DOI:https://doi.org/10.1103/PhysRev.131.2594