Angular-Correlation Study of 27Si Between Ex=2.5 and Ex=5 MeV Using the Reaction 28Si(3He,αγ)27Si

Angular correlations and branching ratios have been measured for the 2.65-, 2.86-, 2.91-, 4.14-, and 4.30-MeV states in ²⁷Si. When combined with the known lifetimes, the results exclude spins 72 and 92 for the 2.86-MeV state and spin 32 for the 2.91-MeV state; the branching ratios suggest that the 2.86- and 2.91-MeV states are the mirrors of states at 2.98 and 3.00 MeV ²⁷Al. The 4.30-MeV state is assigned J^π=52⁺ its decay scheme is very similar to that of the 4.41-MeV state in ²⁷Al. Multipole mixing ratios are presented and compared with the predictions for mirror nuclei recently reported for sd-shell nuclei.