Determination of the asymptoticD- toS-state ratio forHe3via (d→, He3) reactions

Angular distributions of the tensor analyzing powers $A_{\mathrm{yy}}$ and $A_{\mathrm{zz}}$ have been measured for the ground-state transition in the ${}_{}{}^{93}{}_{}{}^{}\mathrm{Nb}(\overrightarrow{d}, {}_{}{}^3{}_{}{}^{}\mathrm{He}){}_{}{}^{92}{}_{}{}^{}\mathrm{Zr}$ reaction at $E_d=12\mathrm{}$ MeV, and of $A_{\mathrm{zz}}$ for the ground-state transitions in ${}_{}{}^{63}{}_{}{}^{}\mathrm{Cu}(\overrightarrow{d}, {}_{}{}^3{}_{}{}^{}\mathrm{He}){}_{}{}^{62}{}_{}{}^{}\mathrm{Ni}$ at $E_d=8\mathrm{}$ MeV and ${}_{}{}^{89}{}_{}{}^{}\mathrm{Y}(\overrightarrow{d}, {}_{}{}^3{}_{}{}^{}\mathrm{He}){}_{}{}^{88}{}_{}{}^{}\mathrm{Sr}$ at $E_d=10.5\mathrm{}$ MeV. The data are compared with predictions of full finite-range distorted-wave Born approximation (DWBA) calculations from which the asymptotic $D$- to $S$-state ratio, $\eta$, for ${}_{}{}^3{}_{}{}^{}\mathrm{He}$ is extracted to be -0.0386±0.0045±0.0012. The difficulties with a choice of deuteron tensor optical potentials used in the DWBA calculations are discussed.