Population of analogs of excited states inCu63(p, n)at 16, 19, and 22 MeV

The ${}_{}{}^{63}{}_{}{}^{}\mathrm{Cu}(p, n)$ analog and excited analog differential cross sections have been measured at bombarding energies of 16, 19, and 22 MeV. Analogs of excited states populated by the ($p, n$) reaction in medium mass odd-$A$ nuclei have not been previously reported. Coupled-channel calculations for the ($p, n$) reaction to the ${\frac{5}{2}}^{-}$ and ${\frac{7}{2}}^{-}$ excited analog states give differential cross sections at 19 and 22 MeV in excellent agreement with measurements. At 16 MeV, the measured ${\frac{5}{2}}^{-}$, ${\frac{7}{2}}^{-}$, and ${\mathrm{½}}^{-}$ cross sections are higher than calculations at the middle angles, perhaps reflecting the contribution from preequilibrium processes. At 16 and 19 MeV the ${\mathrm{½}}^{-}$ angular distribution shapes suggest some spin-flip contribution. The calculated cross section for the ${\mathrm{½}}^{-}$ state is too high at 22 MeV. As in even-$A$ nuclei a two-step mechanism is mainly responsible for the population of excited analog states in ${}_{}{}^{63}{}_{}{}^{}\mathrm{Cu}(p, n)$.