PARTICLE-HOLE YRAST STATES IN GD-146 AND GD-147 AND THE Z=64 SHELL CLOSURE

The level structures of146Gd and147Gd have been investigated by in-beam γ-ray and e- spectroscopy with (α, xn) reactions on enriched Sm targets. Detailed level schemes up to ∼4 MeV, which differ radically from earlier schemes, are reported. The energy levels are characterized as particle-hole excitations using empirical single particle energies and two nucleon interactions. Analysis of pure 1 p 1 h proton excitations demonstrates that the Z=64 and N=82 energy gaps are about equally large. © 1979 Springer-Verlag.