High resolution measurement of proton resonances inCo57

Differential cross sections for the reactions ${}_{}{}^{56}{}_{}{}^{}\mathrm{Fe}$($p$,$p$) and ${}_{}{}^{56}{}_{}{}^{}\mathrm{Fe}$($p$,$p^{\prime }$) were measured at 5 angles from $E_p=3.1\mathrm{} \mathrm{to} 4.0$ MeV with an overall energy resolution of 425-450 eV, full width at half maximum. Over 340 resonances were observed, half of which were $d$-wave levels. Angular distributions of deexcitation $\gamma$ rays were measured for the stronger $l=2\mathrm{}$ resonances and a few $p$-wave resonances to aid in assigning spins. Excitation functions were analyzed with a multilevel, multichannel $R$-matrix formalism. Analogs of the fourteenth (${\frac{5}{2}}^{-}$) and seventeenth through twentieth (${\frac{9}{2}}^{+}$, ${\frac{5}{2}}^{+}$, ${\frac{3}{2}}^{-}$, ${\frac{1}{2}}^{-}$) excited state of ${}_{}{}^{57}{}_{}{}^{}\mathrm{Fe}$ were identified. Coulomb energies, fine structure parameters, and spectroscopic factors for these analogs are given. Proton strength functions are presented, and level densities are compared with semiempirical predictions.