Consistent analysis of collective level structure and neutron interaction data for 12C in the framework of the soft-rotator model

A systematic analysis of nuclear structure and neutron interaction data for 12C was carried out in the framework of the soft-rotator model. The model was firstly applied to analyze the low-lying collective level structure of the 12C nucleus, which turned out to be very successful. The intrinsic wave function obtained in such an analysis was then used to construct the coupling potentials in the coupled-channels formalism to calculate the neutron total and scattering cross sections. The quadrupole deformation parameter obtained in the present analysis was 0.164, which was much smaller in the absolute sense than the value used in the symmetric-rotator, vibrator model employed frequently in the past, i.e., ≅0.6. When averaged over the β-vibration function, however, the present result yields an effective quadrupole strength of about the same scale as the previous studies due to softness of the 12C wave function with respect to β2 degree of freedom. The soft-rotator model was found to be very successful in reproducing both the structure and neutron scattering data consistently for the first time in this mass region. (author)