Generator coordinate method combined with exact triaxial spin projection:: Application to the single-j shell model -: art. no. 044322

The generator coordinate method (GCM) is applied to the single-j shell model with pure quadrupole-quadrupole interaction. The results of the GCM for the j = 15/2 and 19/2 shells are compared with the exact solutions in the shell model. As for the four-hole (or four-particle) systems, the GCM reproduces the shell model results exactly. The half-filled systems are found to exhibit the triaxial rigid rotorlike property against the expectation based on the mean-field theory. The spin-projected potential energy surface offers much more intuitive insight into the shell model spectra than the unprojected one.