1305.4448 (K. Neergård)

Cooperation of anti-aligning and aligning shell-model forces for N=Z    [PDF]

K. Neergård

For two neutrons and two protons or two neutron holes and two proton holes in a single j-shell, the ground state with only a pairing force and the ground state with only an attractive force acting solely on pairs of a quasineutron and a quasiproton with maximally aligned angular momenta overlap considerably for all realistic j, and the state produced with one of these forces has a large content of the pair angular momentum formally favored by the other force. Therefore, these two strongly attractive components of a realistic effective two-quasinucleon interaction cooperate to produce a ground state which is essentially a linear combination of both states with comparable coefficients. In the 1f_7/2 and 1g_9/2 shells, the state produced with only a pairing force makes up about 80 % of the ground state. The overlaps of the latter with both states decrease with increasing j.

View original: http://arxiv.org/abs/1305.4448