Impact of off-diagonal cross-shell interaction on C-14

A shell-model investigation is performed to show the impact on the structure of C-14 from the off-diagonal cross-shell interaction, < pp vertical bar V vertical bar sdsd >, which represents the mixing between the 0 and 2(sic)omega configurations in the psd model space. The observed levels of the positive states in C-14 can be nicely described in 0-4(sic)omega or a larger model space through the well defined Hamiltonians, YSOX and WBP, with a reduction of the strength of the < pp vertical bar V vertical bar sdsd > interaction in the latter. The observed B(GT) values for C-14 can be generally described by YSOX, while WBP and their modifications of the < pp vertical bar V vertical bar sdsd > interaction fail for some values. Further investigation shows the effect of such interactions on the configuration mixing and occupancy. The present work shows examples of how the off-diagonal cross-shell interaction strongly drives the nuclear structure.