A test of the interacting boson approximation using electron scattering

New electron scattering data are presented for levels of 154 Gd. The study includes the three lowest-lying 2 + levels at 0.123, 0.816, and 0.996 MeV excitation energies. These data provide a test of the Interacting Boson Approximation (IBA) prediction that three electric quadrupole transition charge densities are clearly dependent. Deviation of the experimental densities from linear dependence is presented and discussed.