The neutron-capture cross sections of the stable isotopes 106Cd,108Cd,114Cd, and 116Cd have been measured relative to gold by means of the activation method, using the quasi-stellar neutron spectrum for kT = 25 keV that can be produced via the 7Li(p, n)7Be reaction near threshold. These data are given with uncertainties between 3% and 6%, five times smaller than quoted for most of the few previous experiments. The present results complement recent measurements on isotopes of tin and a discussion of the stellar β-decay rates in the A = 113/115 region, and allow an update of the nucleosynthetic origin of the Cd/In/Sn isotopes, which is complicated by the s-process branchings at 113Cd,115Cd, and 115In as well as by the many isomers in this mass region. The s-process yields obtained with the classical s-process and with an AGB model exhibit a significant difference with respect to the cadmium and tin abundances, with interesting consequences for the r-process residuals in this mass region. Nevertheless, the origin of the rare, odd isotopes 113In and 115Sn remains unclear. The cross sections for the two light Cd isotopes, 106 and 108, are of interest for testing Hauser-Feshbach extrapolations to the p-process region.
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