Interplay between particle and core ecitations in $^{133}$Sb
Résumé
The
decay of the one-proton valence nucleus 133Sb is studied using
the cold-neutron induced fission of 235U and 241Pu targets. The experiment
is performed at the ILL reactor in Grenoble, using a highly efficient HPGe
array, also coupled to fast LaBr3(Ce) scintillators. High-spin excited states
above the 16.6 s isomer are observed, and the lifetime of the 13/2+ and
15/2+ states is measured by fast-timing techniques, revealing a complex
nature of the wave functions. The experimental results are well-interpreted
by a newly developed microscopic model which takes into account the coupling
between the valence proton and excitations (both collective and noncollective)
of the doubly magic 132Sn core.