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

20th International School on Nuclear Physics, Neutron Physics and Applications

Sambataro, M.^1 ; Sandulescu, N.^2

Istituto Nazionale di Fisica Nucleare-Sezione di Catania, Via S. Sofia 64, Catania

I-95123, Italy^1

National Institute of Physics and Nuclear Engineering, PO Box MG-6, Magurele, Bucharest, Romania^2

关键词: Diagonalizations;    Finite systems;    Ground-state correlation;    Iterative sequences;    Particle systems;    Realistic applications;    Restricted models;    Time-reversed;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/533/1/012017/pdf
DOI  :  10.1088/1742-6596/533/1/012017

来源: IOP

【 摘 要 】

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.