Study of Proton Particle-Hole States inCa40by theK39(He3, d)Ca40Reaction

Helium-3-induced charged-particle reactions on ${}_{}{}^{39}{}_{}{}^{}\mathrm{K}$ have been studied using a solid-state-detector $\frac{\mathrm{dE}}{\mathrm{dx}}-E$ particle-identification telescope. Elastic-scattering angular distributions at ${}_{}{}^3{}_{}{}^{}\mathrm{He}$ energies of 12, 14, and 16 MeV as well as (${}_{}{}^3{}_{}{}^{}\mathrm{He}$, $d$) angular distributions at 14 MeV have been measured. The reaction data are found to be characterized by extremely weak transitions to all known positive-parity excited states up to 5.3 MeV. Strong transitions to 15 negative-parity states up to 8.6-MeV excitation are observed and identified with the $T=0\mathrm{}$ components of (${d_{\frac{3}{2}}}^{-1\mathrm{}}{f}_{\frac{7}{2}}$) and (${d_{\frac{3}{2}}}^{-1\mathrm{}}{p}_{\frac{3}{2},\frac{1}{2}}$) configurations and the $T=1\mathrm{}$ analogs of the ground-state quarted in ${}_{}{}^{40}{}_{}{}^{}\mathrm{K}$ having the (${d_{\frac{3}{2}}}^{-1\mathrm{}}{f}_{\frac{7}{2}}$) configuration. Since the distorted-wave method does not give a unique prescription for choosing between the various possible optical potentials which fit elastic scattering, a detailed examination is made of the effects of the choice specific ${}_{}{}^3{}_{}{}^{}\mathrm{He}$ and deuteron potentials, of the inclusion of spin-orbit coupling and nonlocality, and of the different approximations for the bound-state wave function; and the significance of the spectroscopic factors is discussed. The distorted-wave results are compared with the revised predictions of Gillet and Sanderson, and it is concluded that above and beyond the inherent uncertainties in the spectroscopic factors, Gillet and Sanderson's theoretical predictions agree poorly with the experimental results.