Measurement of yields and angular distributions of $\gamma$-quanta from the interaction of $14.1$ MeV neutrons with oxygen, phosphorus and sulfur

A study of the inelastic scattering of neutrons with an energy of $14.1$~MeV on the nuclei of oxygen, phosphorus and sulfur was carried out at the TANGRA facility at JINR (Dubna). The purpose of the experiment was to refine existing and obtain new data on the yields and angular distributions of $\gamma$-quanta emitted by the studied nuclei as a result of neutron-induced nuclear reactions using the tagged neutron method. Two types of detector systems were used to register $\gamma$-quanta. The $\gamma$-ray yields were measured using a high-purity germanium (HPGe) detector. The angular distributions of $\gamma$-rays were obtained using a system of 18 scintillation detectors based on bismuth germanite Bi$_{4}$Ge$_{3}$O$_{12}$ (BGO) located around the sample. As a result of the studies carried out, the yields of two transitions for the reaction of tagged neutrons with $^{16}$O, nine transitions for the reaction with $^{31}$P, and nine transitions for the reaction with $^{32}$S were measured for the first time. The angular anisotropy of the $\gamma$-radiation accompanying the inelastic scattering of neutrons with an energy of $14.1$~MeV on $^{31}$P nuclei was also measured for the first time.
Comment: 16 pages, 11 figures. Accepted for publication in Chinese Physics C