Progress of Theoretical Physics

Unitary-Model-Operator Approach to Nuclear Effective Interaction. I: Description of Short-Range Correlations

K. Suzuki

Published Nov 1, 1982• 16 citations

Abstract

A general theory is proposed for the description of short-range correlations of two nucleons in nuclei in the framework of the unitary-model-operator approach. A new effective interaction is derived through the unitary transformation of the original Hamiltonian. The transformed Hamiltonian is given in a cluster expansion form, and the structure of the one- and two-body cluster terms is studied. New aspects of the present approach, compared with the G-matrix theory, are; (i) the new effective interaction is E-independent and Hermitian, (ii) it satisfies the decoupling condition between low- and high-momentum two-particle states, and (iii) it contains both of the contributions of ladder and folded diagrams. It is suggested that the properties (i)∼(iii) of the new effective interaction may offer considerable advantages in accounting manybody correlations and deriving effective interaction among valence nucleons.

DOI: 10.1143/ptp.68.1627

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