Search for a doublet inO16near 9.85 MeV

The region of excitation in ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ near 9.85 MeV has been investigated for evidence of a doublet, expected from tetrahedral symmetry arguments, by using the ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ ${(}^4$He,${\gamma }_3$ ${)}^{16}$O and ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ ${(}^4$He${,}^4$He${)}^{12}$C reactions. Energy-matched measurements of the pair of reactions show no evidence for cascade gamma-ray decay of any but the known D-wave resonance observed in the elastic channel. The gamma-ray decay width of a possible second nondegenerate level to the $2_1^{+}$ state is determined to be less than 5×${10}^{\mathrm{-}4}$ eV.