Structure of the 11/2(-) isomeric state in La-133

摘要

We report measurement of the g-factor for the 11/2(-) isomeric state at 535 keV in La-133, employing the time differential perturbed angular distribution technique (TDPAD). This isomer was populated in the reaction Te-126 (B-11 4n) La-133 at beam energy of 52 MeV. From the observed nuclear spin precession, analysed through combined, magnetic dipole and electric quadrupole hyperfine interactions, we obtain the g factor for the 11/2(-) state as g = 1.16 +/- 0.07. In addition, this analysis provides the spectroscopic quadrupole moment vertical bar Q vertical bar = 1.71 0.34 b, yielding the deformation parameter beta = 0.28 +/- 0.10. Further, we have performed theoretical calculations using the large-scale shell model and the Monte Carlo shell model. The results successfully describe the lowlying levels and the band structures of La-133, and the calculated g factor compares well with the values obtained from our experiment. The dominant configuration of 11/2(-) isomeric state in La-133 is inferred to be pi(h(11)(/2)) circle times Ba-132 (0(+)).