Radiative decay of the 15.235 MeV level in²⁸Si

Summary

In²⁷Al(p, γ)²⁸Si reaction, a narrow resonance was located for the incident proton energyE _p=3.785 MeV. It is tentatively identified as the analogue of the 5.91 MeV level in²⁸Al. It is found to populate only levels of high spin (J≥3) and the angular distributions are consistent with spin-parity assignment ofJ ^π=3⁺ for the resonance. Gamma-decay strengths and branching ratios are deduced. The transition strengths from the otherJ ^π=3⁺,T=1 are compiled and compared against the strength expected from the positron decay of the ground state of²⁸P (J ^π=3⁺). It is apparent that there is considerable configuration mixing among theJ ^π=3⁺,T=1 levels in²⁸Si.