Alpha decay widths of excited states of 16O

The 12C(13C, 9Be)16O reaction has been used to populate excited states in 16O. The 9Be nuclei were detected in a magnetic spectrometer and the 12C decay product of the recoiling excited 16O nucleus was detected in an array of silicon strip detectors. The large angular coverage of the strip detector array allowed the α-decay widths of the 14.66 MeV, 5−, and 16.275 MeV, 6+, states to be determined with good accuracy. The present results, together with earlier measurements, allow precise values for the branching ratios to be calculated: Ex(16O) = 14.66 MeV, Jπ = 5−, Γα0/Γ = 0.951 ± 0.049 and Γα1/Γ < 0.05; Ex(16O) = 16.275 MeV, Jπ = 6+, Γα0/Γ = 0.982 ± 0.048 and Γα1/Γ < 0.02.