AN IBA-2 CALCULATION OF E2 M1 MULTIPOLE MIXING RATIOS OF TRANSITIONS IN W-182, W-184, W-186/

The tungsten isotopes (Z = 74) lie in the transitional region that occ urs at the upper limit of the range of deformed nuclei. Energy levels, B(E2) and B(M1) values and gamma-ray E2/M1 mixing ratios for selected transitions in W-182, W-184, W-186 are calculated in the proton-neutr on interacting boson approximation (IBA-2). The Majorana parameters ar e found to have a great effect on the energy of mixed-symmetry states as well as on the sign and magnitude of the E2/M1 mixing ratios of tra nsitions between regular (symmetric) states. The results demonstrate t he sensitivity of the sign and magnitude of delta values on particular IBA-2 parameters.