Excited states in Sm-139 described with the interacting boson model plus broken pairs

The high-spin structure of Sm-139 has been studied through the Pd-110(S-34,5n) reaction at beam energies of 150 and 165 MeV. The level scheme has been extended up to an excitation energy of 11.1 MeV and spin 61/2(+). A band built on the vi(13/2) [660]1/2(+) intruder orbital has been established and firmly linked to the known lower-spin levels in the nucleus. The low-lying states of both parities as well asa relatively strong Delta I=1 regular structure observed above spin 27/2(-) are nicely reproduced by the interacting boson-fermion model with broken pairs.