Nuclear structure of the neutron-rich 140-148Ba isotopes

The level structure of even-even neutron-rich 140-148Ba isotopes was studied in the framework of the interacting boson model. The reduced transition probabilities B(E2) of these nuclei was calculated. A set of parameters was used in the calculation to approach the values with the measured data. It was pointed out that interacting boson approximations are equitably reliable for the description of spectra and other properties. It was found that there is a rapid transition between spherical and rotational shapes.