Structure Evolution in the Even-Even ^124-134Xe with IBM2

We have investigated the structure evolution of the ^124-134Xe isotopic chain in the framework of the proton-neutron interacting model IBM2. The positive parity spectra of the ground state, quasi-β and quasi-γ bands are reproduced well. The staggering in ^124-130Xe are almost completely removed and the ？ band agree well with the experiment data, even for the high-spin quasi-3 states. The key quantities of the collective structure evolution, including level energies, the B（E2） transition branching ratios, and the M1 excitations to 11^＋ mixer-symmetry states are analyzed by comparing with the experimental data. The parameters for representation of the Oπν（6） and SUπν^＊（3） features in isotopes are examined. Both experimental data and theoretical results show that the shape phase transition of ^124-134Xe isotopic chain is from the SUπν^＊ （3） （triaxial rotation） to the Uπν（5） （vibration motion） with a considerable constituent of the Oπν（6） symmetry （γ-unstable rotation）, where the shape phase transition rapidly takes place between the neutron number N = 76 and N = 78.