Nuclear-Structure Studies with (d, p) Reactions onPd106andPd108

Abstract

Energy distributions of protons emitted at various angles from 12-MeV-deuteron-induced ($d, p$) reactions on ${\mathrm{Pd}}^{106}$ and ${\mathrm{Pd}}^{108}$ were measured with 7-keV energy resolution using an Enge split-pole spectrograph. The results for the two isotopes are very similar except that summed spectroscopic factors are a little smaller in ${\mathrm{Pd}}^{108}$, as expected from the fact that it has more neutrons. The level densities were found to be about 25 levels per MeV, and the single-particle levels are fragmented over a wide range of energies, although a large fraction of the strength of single-particle levels in the 50-82 shell is always in the lowest-lying nuclear level. The $l=4$ strengths seem to be too large, and the $\frac{(d, p)}{(d, t)}$ cross-section ratio of one of these states in each isotope indicates that it may be ${g}_{\frac{9}{2}}$ rather than ${g}_{\frac{7}{2}}$; the ${h}_{\frac{11}{2}}$ strengths are too small. Possible explanations for this are discussed, including the possibility that these nuclei are strongly deformed. The $s$ and $d$ states are somewhat more full in ${\mathrm{Pd}}^{108}$ than in its isotone ${\mathrm{Sn}}^{112}$.