Proton-Induced Reactions onAr40and Analogs ofAr41Levels

Excitation functions have been measured at several angles between 58° and 161° for the ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ar}\mathrm{}(p,p)\mathrm{}{}_{}{}^{40}{}_{}{}^{}\mathrm{Ar}$, ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ar}(p,p^{\prime }){}_{}{}^{40}{}_{}{}^{}\mathrm{Ar}_{}^{*}{}_{}{}^{}$ (first excited level), and ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ar}(p,\alpha ){}_{}{}^{37}{}_{}{}^{}\mathrm{Cl}$ reactions. Differential cross sections were measured in 3-keV steps with an energy resolution of 3 keV for incident proton energies from 1.81 to 4.35 MeV. The structures observed in the proton inelastic scattering yields and $\alpha$-particle yields were not completely resolved. Averaging the cross sections with an interval of ∼25 keV revealed a residual resonance structure with widths and spacings between 10 and 40 keV, interpreted as analog resonances. Seventeen resonances are included in an analysis of the averaged cross sections for proton elastic and inelastic scattering. Eight of these correspond to known levels of ${}_{}{}^{41}{}_{}{}^{}\mathrm{Ar}$. Reduced proton widths of the eight analogs imply neutron spectroscopic factors for bound levels of ${}_{}{}^{41}{}_{}{}^{}\mathrm{Ar}$ in agreement with those extracted from an analysis of the ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ar}\mathrm{}(d,p)\mathrm{}{}_{}{}^{41}{}_{}{}^{}\mathrm{Ar}$ reactions.