Gamma Rays from the Proton Bombardment of ³¹P and the Excited States of ³¹P

Abstract

Gamma rays from ³¹P bombarded by protons of up to 5.7 MeV energy were analysed by scintillation spectrometers. Most of the observed gamma rays were attributed to the transitions from the excited states of ³¹P produced by the inelastic scattering of protons. Gamma ray transition branching ratios from several excited states were determined. The results are in general agreement with the results obtained from the experiments on ³⁰Si(p, γ)³¹P reaction, but there are some differences between them which are discussed in detail. In particular, it was noted that the gamma ray of 1.65 MeV energy resulting from the transition from the excited state at 4.784 MeV to 3.133 MeV state is emitted in considerable intensity at the proton bombarding energy of 5.7 MeV. It was suggested that this selective excitation might be the result of the collective nature for the 4.784 MeV excited level. Excitation curve for the gamma ray intensity gave the compound levels of ³²S at 13.61, 13.97 and 14.27 MeV.