Pairing models of Pb206, Pb204 and Pb202

Abstract

Exact eigenstates of the pairing-force Hamiltonian are used to study paring models of Pb206, Pb204 and Pb202. The properties of the eigenstates are discussed as functions of the interaction strength g and numerical results are given for g = 0.146 MeV. This interaction strength is stronger than the value, g = 0.111 MeV, adopted in a previous study of these models which used the approximate methods of the theory of superconductivity. However, using the exact eigen states and the stronger pairing interaction, the experimentally observed spectra of these three nuclei are predicted with an average error of 0.1 MeV. This error is as large as that of the approximate calculation in which the weaker pairing interaction was used.