Level Structure ofCd109from the Decay ofIn109

The excited levels of ${\mathrm{Cd}}^{109}$ have been investigated from the decay of ${\mathrm{In}}^{109}$ with high-resolution Ge(Li) and Si(Li) detectors as well as with standard scintillation counters. ${\mathrm{In}}^{109}$ was produced by the ($\alpha ,n$) reaction on enriched ${\mathrm{Cd}}^{106}$. This reaction produced ${\mathrm{Sn}}^{109}$, which decays with a short half-life to ${\mathrm{In}}^{109}$. Levels of the following energies (in keV) have been established in ${\mathrm{Cd}}^{109}$: 59.5, 203.3, 347.4, 426.2, 623.8, 673.7, 721.5, 822.5, 997.5, 1352.2, 1475.6, 1539.8, 1622.5, and 1772.6. The use of two Ge(Li) detectors in connection with the PDP-8/I and a program for two-dimensional analysis with a 4096-dual analog-to-digital converter revealed the presence of several previously unreported transitions in ${\mathrm{In}}^{109}$. Based on the $\gamma -\gamma$ and $\beta -\gamma$ coincidence results, a consistent level scheme for ${\mathrm{Cd}}^{109}$ is given. The spin and parity assignments of levels of ${\mathrm{Cd}}^{109}$ are discussed.