Beyond-mean-field-model analysis of low-spin normal-deformed and superdeformed collective states of^{32} S,^{36} Ar,^{38} Ar, and^{40} Ca

Vrije Universiteit Brussel, Bruxelles, Brussels Capital, Belgium
Physical Review C (Impact Factor: 3.88). 10/2003; 68(4). DOI: 10.1103/PhysRevC.68.044321
Source: arXiv

ABSTRACT We investigate the coexistence of spherical, deformed, and superdeformed states at low spin in 32S, 36Ar, 38Ar, and 40Ca. The microscopic states are constructed by configuration mixing of BCS states projected on good particle number and angular momentum. The BCS states are themselves obtained from Hartree-Fock BCS calculations using the Skyrme interaction SLy6 for the particle-hole channel and a density-dependent contact force in the pairing channel. The same interaction is used within the generator coordinate method to determine the configuration mixing and calculate the properties of even-spin states with positive parity. Our calculations underestimate moments of inertia. Nevertheless, for the four nuclei, the global structural properties of the states of normal deformation as well as the recently discovered superdeformed bands up to spin 6 are correctly reproduced with regard to both the energies and the transition rates.

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