${\mathrm{O}}^{16}(p, p){\mathrm{O}}^{16}$ differential cross-section data for $E_p=2-7.6\mathrm{}$ Mev have been used to fix parameters of ${\mathrm{F}}^{17}$ levels. The cross-section data were first fitted to a partial-wave phase-shift expansion by a least-squares method using an IBM 704. The level parameters were then obtained by application of dispersion formalism to the extracted phase shifts. The two-level approximation was used where appropriate. Four very narrow levels and the well-known $\frac{7}{2^{-}}$ level at $E_p=3.47\mathrm{}$ Mev were ignored in the present analysis. However, resonant energies and limits on widths (obtained by inspection) for these and higher energy ${\mathrm{F}}^{17}$ states are given. Level schemes of ${\mathrm{O}}^{17}$ and ${\mathrm{F}}^{17}$ are compared. Assignment of levels to particular nuclear configurations is attempted. An appendix is included, giving illustrations of branching solutions in the phase-shift analysis.

• Received 1 February 1962

DOI:https://doi.org/10.1103/PhysRev.126.2147