Proton-neutron structure of collective excitations in ⁹⁴Mo

Abstract:

Resulting wave functions of low-lying J ^π = 2⁺ states from a recent shell model calculation for the near-spherical nucleus ⁹⁴Mo are analyzed with respect to their collectivity and the proton-neutron degree of freedom. The analysis uses the Q-phonon scheme applied to the shell model and it supports the mixed-symmetry interpretation of the interacting boson model for the multiphonon structure observed recently in ⁹⁴Mo by means of γ-ray spectroscopy. Simple operators are obtained which generate major parts of the symmetric- and mixed-symmetry 2⁺ states in ⁹⁴Mo when applied to the calculated ground state.