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A 70 ns isomeric state at 2 641 keV has been produced in the 209Bi(α,2n)211 At reaction and interpreted as the 29/2+ state of the h 9/2 2 i 13/2 proton configuration. It decays to the states (h 9/2 2 f 7/2)23/2, (h 9/2 3)21/2, (h 9/2 3)17/2, (h 9/2 3)13/2 and (h 9/2 3)9/2 by a straight cascade of transitions with energies (multipolarities) 713.3 keV (E3), 511.6 keV (M1), 96.0 keV (E2), 253.4 keV (E2), and 1 066.9 keV (E2). There is also indirect evidence for a 24.4 keV (E2) branch to a (h 9/2 2 i 13/2)25/2 state followed by a 688.9 keV (E1) transition to the 21/2- state. The reduced transition rate B(E3, 29/2+ → 23/2-) = 51 000 e 2 fm6 can be reproduced by taking the value 0.9 MeV for the particle-phonon coupling matrix element ⟨i 13/2, 3-; 7/2|H coupl|f 7/2⟩.

Using alpha particles from the Stockholm 225-cm cyclotron, gamma rays from the 208Pb(α, 3n) reaction have been studied. Excitation functions, angular distributions, prompt and delayed gamma rays and gamma-gamma coincidences were measured. The results give strong evidence for a 31/2- isomeric state in 209 84Po125 with a half-life of 118 ± 3 ns, which is interpreted as being mainly due to the core-excited πh 9/2πi 13/2νg 9/2 (ν-2)0+ configuration.

High-spin levels in 2~ populated in the 2~ were studied using c~-particles in the energy region 41-51 MeV. The energies of levels above the 6 + level have an uncertainty of about 10 keV due to the fact that the 8 +--.6 + transition has not been observed so far, but this transition has previously been established to be converted neither in the K-shell nor in the L-shells. It was found that the yrast cascade of y-rays from a 19 + level at 5896+ekeV feeds levels of lower spin which all can be explained as originating from two proton-two neutron hole configurations. In the higher part of the cascade it is mainly the neutron holes which change their configuration, while the lower part of the cascade is dominated by changes in the proton configuration. The yrast levels in the angular momentum region J--8-19 vary practically linearly with energy in the region 1.5-6 MeV. No isomeric traps were found above the 11-level at 2699 + e keV.