Band crossings in mercury nuclei: effect of occupation of i13/2 neutron orbits

The K=0+ ground band and two rotation-aligned bands (K=1+ or K2+ two quasi-particle band and K=2+ four quasi-particle band) are studied in 198Hg, 194Hg and 190Hg by angular momentum projection from Hartree-Fock and particle-hole intrinsic states. There is a first anomaly in these three nuclei around 8(h/2π) due to the crossing of the ground band and the two quasi-particle band. Because of the nature of occupation of i13/2 orbitals the four quasi-particle band is too highlying in 198Hg and does not cross the two quasi-particle bands, while such a second crossing occurs in 194Hg and 190Hg near 20 (h/2π). (author)