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Abstract:: High-spin states in 208Pb have been studied by γ-ray-spectroscopy methods in deep inelastic reactions induced by beams of 208Pb, 136Xe and 76Ge beams on a thick 208Pb target. The 11+2 state and new γ-transitions between the one-particle one-hole states of highest spin have been found and electromagnetic matrix elements verified. High-spin states of two-particle two-hole structure have been detected for the first time. The results are compared to shell model calculations with realistic interactions in the complete Kuo-Herling space.

Reaction product cross sections have been measured for reactions of4He projectile with54,56Fe,58Ni and59Co targets in the bombarding energy range 14–27 MeV. The cross-section-weighted average charge $$\overline {\Delta Z}$$ and mass $$\overline {\Delta A}$$ removed from the compound system were deduced and compared with results reported for heavy-ion induced reactions. Variation of $$\overline {\Delta A}$$ with ECN* is independent of the initial angular momentum of compound nucleus in theA=60 mass region in contrary to the rare-earth region. This would suggest a strong angular momentum removal from the compound nucleus by evaporation of particles forA˜60 nuclei. The average evaporated charge $$\overline {\Delta Z}$$ depends on both the CN excitation energy ECN* and the compound nucleusN andZ numbers. The $$\overline {\Delta A}$$ and $$\overline {\Delta Z}$$ dependence on excitation energy and the projectile-target combination can be understood in terms of the statistical model calculations.

Abstract:: Prompt and delayed γ-rays in nuclei of the 208Pb region produced in 450 MeV 76Ge +208Pb collisions have been studied at GASP. Yrast states above the α-decaying isomer in 211Po have been located including a 0.25 μs 31/2− isomer at 2135 keV and a 2 μs isomer at 4874 keV.

Gamma-ray studies of130Te+275 MeV64Ni reaction products have identified yrast states of129Te up to a 33 ns isomer at 2138 keV. Theß--decay of 17.7 min129Sb to levels in129Te is elucidated.