Structure of high-spin yrast states in 205Pb and 206Pb

The properties of high-spin states in Pb and Pb have been investigated using the Hg(Be, α4n)Pb and Hg(Be, α3n)Pb reactions at a bombarding energy of 62 MeV. Decay properties for states up to an excitation energy of 6866 keV and spin of ( 37 2) have been deduced for Pb, and up to an excitation energy of 8705 keV and spin of (21) for Pb. The level schemes are compared with predictions of multi-particle shell-model calculations. The observation that the yrast 33 2 isomer in Pb is essentially bypassed is explained as a consequence of the absence of related configurations of higher spin near the yrast line