Higher-shell corrections for systems with one and two valence nucleons: A spin-orbit and tensor interaction analysis

It is shown that when higher-shell admixtures are included for systems with two valence particles or holes, there are effects which are quite different from those for one-valence-nucleon systems. For example, for nuclei with one valence particle or hole, there is no first-order correction for the magnetic dipole moment or the Gamow-Teller transition amplitude. However for nuclei with two valence particles or holes, one can get substantial corrections. The effects of the tensor and spin-orbit interactions in core renormalization are emphasized. We find that in 6Li, the spin-orbit interaction causes the quadrupole moment of the J=1+ ground state to be positive, but the tensor interaction causes it to be negative. The G-matrices derived from realistic interactions are employed in these calculations.