High-spin yrast isomers in $^{204}$HG

This work reports the observation of high-spin states in 204Hg using time-correlated γ-ray spectroscopy to identify isomers populated in deep-inelastic collisions of a ~1.4 GeV 208Pb beam on a thick 238U target. A high-spin isomer with τ>1 μs has been found and the observed γ-ray decay has established the yrast states below it, including another isomer with τ=33(3) ns. Spin and parity assignments were based on conversion coefficients deduced from intensity balance and on the observed γ-decay patterns. The experimental results are compared with shell model calculations that include four holes in the entire configuration space between 132Sn and 208Pb. Observed agreement with the calculation gave the supplementary arguments to the spin-parity assignments and clarified configurations of experimental states. The τ>1 μs isomer is suggested to be the πh-2 11/2ν-2 13/2, 22+ states that results from the coupling to maximum spin available for the four valence holes. Few prompt transitions feeding the isomer were also observed