0000000000515030
AUTHOR
C J Herrlander
On the Yrast Structure of206Po
Excited states in 206Po with spins up to 16 were identified through reactions with 3He- and α-particles on targets of 206Pb. Level and transition properties were studied using conventional in-beam γ-ray and conversion electron spectroscopy. The half-life of the yrast 9- state, identified as the neutron two-quasiparticle state ν(f5/2-1i13/2-1)9-, was determined as 1.0 μs. No other isomers, besides the previously known isomeric 8+ state, were observed. The excited states are classified within the shell-model description. Transition probabilities are discussed.
Evidence for Two-Nucleon Polarization in the π(h9/2i13/2)11- ν(j-2)0+ Level in 208Po
From in-beam gamma-ray spectroscopy measurements on the 208Pb(α, 4n)208Po reaction using the Stockholm 225-cm cyclotron, we have concluded that there is an 11-, 8 ns isomeric state in 208Po, which lies 1 175 keV above the π(h 9/2 2)8+ state and that this isomeric state should have the configuration π(h 9/2 i 13/2)11- ν(j -2)0+. Calculations based on the use of empirical two-particle interactions give a position of the 11- level which deviates by about + 100 keV from the experimentally found position. It is suggested that this deviation is mainly due to the difference in the polarization of the 206Pb-and 208Pb-cores by the two aligned h 9/2 and i 13/2 protons.