Proton Capture Gamma Rays from the ReactionP31(p, γ)S32Leading to the Ground and First Excited States ofS32

Abstract

Resonances in the reaction ${\mathrm{P}}^{31}(p, \gamma ){\mathrm{S}}^{32}$ which show transitions to the ground or first excited state of ${\mathrm{S}}^{32}$ have been studied for proton energies between 0.68 and 2.35 Mev. Angular distributions have been measured at resonances at 0.816, 0.825, 1.117, 1.146, 1.248, 1.892, 1.985, 2.027, 2.120, 2.320, and 2.340 Mev. These distributions along with the ${\mathrm{P}}^{31}(p, {\alpha }_0){\mathrm{Si}}^{28}$ results enabled assignments of 1- to be made for the resonances at 1.892, 2.027, and 2.120 Mev, of 1± for those at 0.825, 1.117, 1.985, 2.320, and 2.340 Mev, and of 2± to that at 1.248 Mev. Partial widths for ${\gamma }_0$ and ${\gamma }_1$ were also measured and are compared with theory. Analysis of the angular distributions at one resonance suggests that the spin of the first excited state of ${\mathrm{S}}^{32}$ at 2.25 Mev is 2+. The reduced proton widths for the three resonances with $J=1-$ together amount to 60 percent of the single-particle width.