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An effective residual interaction between particles and holes for shell model calculations around 208Pb, derived from the interaction between free nucleons, is compared with the measured properties of proton-hole neutron states in 208Tl and the interaction between proton holes is adjusted to newly measured level energies in 206Hg. These interaction elements are particularly relevant for neutron-rich nuclei. The adjustment of two mixing elements reproduces the known γ-decay data in 208Tl. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The present status of experimental approach to Sn in the spectroscopy of excited states is landmarked by the T=3/2 nuclei between Pd and In and the T=1 nuclei Pd and Cd. The detection limits with Pre-EUROBALL γ-arrays and ancillary detectors are below the 10 level of the total fusion- evaporation residue cross section. A large scale shell model analysis of the existing data reveals the shell structure at Sn, which shows a remarkable similarity to Ni. Evidence for an increasing proton-neutron interaction in approaching the N=Z line is deduced from high spin isomers and spherical yrast lines. The effective E2 operator for protons and neutrons and implications for a low lying particle-hole (ph) E2 excitation in Sn are discussed. [ABSTRACT FROM AUTHOR]

The high-spin states of 147Tb have been studied with regard to their spins. The data were obtained by in-beam γ-ray spectroscopy using the reaction 120Sn(31P,4n)147Tb at 152 MeV performed at the Osiris spectrometer in Berlin. We obtained multipole mixing ratios for 60 transitions, and level spins up to 67/2ħ are introduced. [ABSTRACT FROM AUTHOR]

High spin states in nuclei around 208Pb were populated in deep inelastic collisions of 76Ge, 136Xe, and 208Pb projectiles with 208Pb targets at beam energies about 12% above the Coulomb barrier. New states in 209Pb were found by measuring γ-γ-coincidences. They are interpreted as the yrast states that originate from the coupling of one neutron to the lowest excitations of the 208Pb core. The results are discussed in the frame of the shell model. [ABSTRACT FROM AUTHOR]

The neutron deficient 199At nucleus has been studied in the 175Lu+28Si reaction at Eb= 141 MeV. In order to select events of interest in the presence of the very strong background caused by fission, γ-rays have been detected in coincidence with recoiling evaporation residues. The excited states of 199At observed for the first time may indicate that this nucleus is deformed. [ABSTRACT FROM AUTHOR]