Low-Lying Levels inCa42Excited by theCa43(d, t)Reaction

Angular distributions of triton groups corresponding to ($d, t$) transitions to five states in ${}_{}{}^{42}{}_{}{}^{}\mathrm{Ca}$ have been observed at a bombarding energy of 8.522 MeV. The tritons were recorded in a multigap broad-range spectro-graph. The elastic scattering of deuterons from ${}_{}{}^{43}{}_{}{}^{}\mathrm{Ca}$ was also measured and fitted with an optical-model potential, which was then used in a distorted-wave analysis of the ($d, t$) cross sections. The results are in good agreement with the predictions for an ${\left(f_{\frac{7}{2}}\right)}^3$ configuration for ${}_{}{}^{43}{}_{}{}^{}\mathrm{Ca}$ and ${\left(f_{\frac{7}{2}}\right)}^2$ for ${}_{}{}^{42}{}_{}{}^{}\mathrm{Ca}$, except that the $2^{+}$ parentage is split approximately equally between the 1.53- and 2.44-MeV states of ${}_{}{}^{42}{}_{}{}^{}\mathrm{Ca}$. The data do not allow $l=1\mathrm{}$ pickup with more than a few percent of the single-particle strength. Transitions to the second $0^{+}$ state at 1.84 MeV are not observed. The results are discussed in terms of the seniority coupling scheme and in terms of the shell model with residual interactions.