On unitarity of the particle-hole dispersive optical model

TL;DR

This paper examines unitarity violations in the particle-hole dispersive optical model and proposes methods to restore unitarity, demonstrating their effectiveness on 208Pb for giant resonance properties and neutron decay analysis.

Contribution

It introduces unitarity restoration techniques for the particle-hole dispersive optical model and applies them to analyze giant resonances and neutron decay in 208Pb.

Findings

Unitarity violations are identified and addressed in the model.

Restoration methods improve the description of resonance properties.

The model successfully describes neutron decay processes.

Abstract

For the recently developed particle-hole dispersive optical model, weak violations of unitarity due to a phenomenological description of the spreading effect are considered. Methods for unitarity restoration are proposed and implemented for the 208Pb nucleus in the description of the energy-averaged isoscalar monopole double transition density and strength functions in a wide excitation energy interval that includes the isoscalar giant monopole resonance and its overtone. To illustrate abilities of the model, direct neutron decay of the mentioned giant resonance is also considered.