Nuclear-Reaction Studies in the Nickel Isotopes: TheNi58(p,p′)Ni58andNi58(d,p)Ni59Reactions

Abstract

The reactions ${\mathrm{Ni}}^{58}(p,p^{\prime }){\mathrm{Ni}}^{58}$ and ${\mathrm{Ni}}^{58}\mathrm{}(d,p)\mathrm{}{\mathrm{Ni}}^{59}$ have been studied at a bombarding energy of 7.0 MeV using the MIT-ONR Van de Graaff generator and both the single-gap and multiple-gap broad-range spectrographs. With an energy resolution of better than 10 keV, fourteen levels in ${\mathrm{Ni}}^{58}$ were observed up to 4.2-MeV excitation; and in ${\mathrm{Ni}}^{59}$, 173 levels were observed up to an excitation energy of 7.5 MeV. $Q$ values and positions of energy levels for both reactions have been measured with accuracies between 5 and 10 keV using the single-gap spectrograph. In the ${\mathrm{Ni}}^{58}\mathrm{}(d,p)\mathrm{}{\mathrm{Ni}}^{59}$ investigation, simultaneous proton spectra were obtained at 24 reaction angles with the multiple-gap spectrograph. The angular distribution of the proton groups showing stripping characteristics were analyzed by use of the distorted-wave Born approximation. Absolute differential cross sections for all levels have been measured, and the values of $l_n$, the orbital angular momentum of the transferred neutron, and the strength functions $\mathrm{}(2J+1)\mathrm{}{S}_{l_n,j}$ for the stripping levels have been obtained. A sum-rule analysis is made, and the results are compared with shell-model predictions.