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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.

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Using a-particles in the energy range 42-51 MeV, the 2~ 4n)Z~ reaction was studied with the intention of investigating the properties of excited high spin states in 2~In-beam prompt and delayed gamma-ray and conversion electron spectroscopy reveal two isomeric states at 2 429 and 1428 keV having the half-lives of 875 + 100 ns and 25 _+ 1 ns, respectively. The spins and parities of these states are found to be 29/2 + and 21/2-, respectively. The g-factors of the isomeric states are 1.06__+0.02 and 0.88_+0.06, which, within the experimental errors, are the same as the g-factors of the corresponding states in 211At. This suggests that the isomeric states are due to the n(hZ/2)s + it3/zV(j-2)O + and n(h39/2) v(j-:)o + configurations, respectively. The deviation between the calculated and experimentally found excitation energies of the isomeric levels are -146_+26 and +72_+ 26 keV. This deviation which in cases of a 2~ usually is smaller than 15 keV, is likely to be due to the neglect of the interaction between two particles via the exchange of virtual 2 + phonons in the 2~ core. This two-particle polarization interaction is found to be approximately described by a P2-force.

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