Angular Distribution of Photons in Light-Particle-Induced Reactions on the \({}^{{12}}\)C Nucleus from Analysis of Particle–\({\gamma}\) Correlations

The angular-correlation function for a final particle \(y\) and a photon is used to analyze gamma radiation that deexcites the nucleus produced in a nuclear reaction. The experimentally measured and calculated angular distributions of gamma radiation accompanying the deexcitation of \({}^{12}\)C(\(2^{+}\)) nuclei in reactions of inelastic deuteron and neutron scattering are compared. In the inelastic scattering of 15.3-MeV deuterons, this analysis was performed with the aid of the experimental and calculated values that we determined earlier for the spin-tensor components \(A_{k0}(\theta_{d})\) of the \({}^{12}\)C(\(2^{+}\)) density matrix. In the inelastic scattering of 14.1-MeV neutrons, the experimental angular distribution of photons that was obtained by the TANGRA Collaboration is contrasted against its counterpart calculated on the basis of the spin-tensor components \(A_{k0}(\theta_{n})\) determined by means of the coupled-channel method. The normalized angular distributions of photons agree with the experimental ones both in deuteron and in neutron scattering. It is shown that the anisotropy of gamma radiation in inelastic neutron scattering is greater by a factor of about 1.5 than that in inelastic deuteron scattering.