An improved variational ansatz is proposed and implemented for variational many-body wave functions for light nuclei with nucleons interacting through Argonne (AV${}_{18}$) and Urbana IX (UIX) three-nucleon interactions. The new ansatz is based upon variationally distinguishing between the various components of the two-body Jastrow and operatorial correlations, which are operated upon by three-body and spin-orbit correlations. We obtain noticeable improvement in the quality of the wave function and lowering of the energies compared to earlier results. The new energies are −8.38(1), −28.07(1), and −29.90(1) MeV for ${}^3$H, ${}^4$He, and ${}^6$Li, respectively. Though, the present improved ansatz still fails to stabilize the ${}^6$Li nucleus against a breakup into an α particle and a deuteron by 390 KeV; nonetheless, it is an improvement over previous studies.

• Received 21 June 2012

DOI:https://doi.org/10.1103/PhysRevC.86.034323