To resolve the reported anomalous behavior of the a-decay rates of 186 -188 ' 1 90,i92p^ we determined more accurate a-decay branches for these isotopes. Our data result in a-decay reduced widths whose dependence on TV is similar to that observed for other elements. However, contrary to the expectation of a shell effect at Z = 82, this new information indicates lead nuclei to be less hindered toward a decay than mercury isotopes. It appears that midway between N = 82 and N = 126 the proton number of 82 is not magic.

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