The NaI scintillation spectroscopy of the proton groups from the inelastic scattering of 19-Mev protons by ${\mathrm{O}}^{16}$ yielded levels in ${\mathrm{O}}^{16}$ at 6.14, 7.02, 8.87, 9.85, 10.34, 11.08, 11.51, 12.02, 12.53, 13.06, and possibly 13.39 Mev, with an error of ±30 kev. The levels at 8.87 and 11.08 Mev are probably $2^{-}$ in character and are found to decay by $\gamma$ rays cascading through the states at 6 and 7 Mev. The relatively weakly excited level at 12.02 Mev is probably accompanied by $\gamma$-ray emission. Differential cross sections for most inelastic groups are also given.

• Received 3 August 1955

DOI:https://doi.org/10.1103/PhysRev.100.1409