Core-excited states and the yrast line in 208Po

Abstract

The properties of high-spin states in 208Po have been investigated using the 204Hg( 9Be,5n) 208Po reaction at a bombarding energy of 62 MeV. Decay properties for states in 208Po up to an excitation energy of 9643 keV and spins up to J = 24 have been deduced. The level scheme is compared with predictions of multi-particle shell-model calculations and evidence is presented that the coreexcited states intrude into the decay sequence at an excitation energy near 6500 keV, although they do not form isomers. Above 7.5 MeV the yrast line is dominated by core-excited states.