Accuracy of the new pairing theory and its improvement

Abstract

Recently I proposed a new method for solving the pairing Hamiltonian with the pair-condensate wavefunction ansatz based on the Heisenberg equations of motion for the density matrix operators. In this work an improved version is given by deriving the relevant equations more carefully. I evaluate both versions in a large ensemble with random interactions, and the accuracy of the methods is given statistically in terms of root-mean-square derivations from the exact results. The widely used variational calculation is also done and the results and computing-time costs are compared.

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• Systematic investigation of the high-$K$ isomers and the high-spin rotational bands in the neutron rich Nd and Sm isotopes by a particle-number conserving method
• Solving for the Particle-Number-Projected HFB Wavefunction
• Configuration and bandhead spin assignments for the 2-quasiparticle rotational bands in the neutron-rich nuclei ${}^{154,156}$Pm
• Band crossings in ${}^{168}$Ta: a particle-number conserving analysis
• Systematic investigation of the high-spin structures in the odd-odd nuclei ${}^{166,168,170,172}$Re by a particle-number conserving method