Journal of Physics Conference Series

Description of pairing in finite like-particle systems in a formalism of quartets

Michelangelo Sambataro, Nicolae Sandulescu

Published Sep 10, 2014• 0 citations

Abstract

We provide a description of the ground state correlations induced by a general pairing Hamiltonian in a finite system of like fermions in terms of four-body correlated structures (quartets). These are real superpositions of products of two pairs of particles in time-reversed states. Quartets are determined variationally through an iterative sequence of diagonalizations of the Hamiltonian in restricted model spaces and are, in principle, all distinct from one another. The ground state is represented as a product of quartets to which, depending on the number of particles (supposed to be even, in any case), an extra collective pair is added. The extra pair is also determined variationally. We show some realistic applications of the quartet formalism in the case of Sn isotopes.

DOI: 10.1088/1742-6596/533/1/012017

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