Particle-Hole Optical Model: Fantasy or Reality?

TL;DR

This paper explores a novel optical model for particle-hole excitations, using the Bethe-Goldstone equation to incorporate complex interactions and spreading effects, aiming to assess its practical viability.

Contribution

It introduces a particle-hole optical model based on the Bethe-Goldstone equation, highlighting the role of energy-dependent interactions and their imaginary components.

Findings

Formulation of a particle-hole optical model using Bethe-Goldstone equation

Identification of energy-dependent interactions responsible for spreading effects

Analogy established between single-quasiparticle and particle-hole optical models

Abstract

An attempt to formulate the optical model of particle-hole-type excitations (including giant resonances) is undertaken. The model is based on the Bethe--Goldstone equation for the particle-hole Green function. This equation involves a specific energy-dependent particle-hole interaction that is due to virtual excitation of many-quasiparticle configurations and responsible for the spreading effect. After energy averaging, this interaction involves an imaginary part. The analogy between the single-quasiparticle and particle-hole optical models is outlined.