A novel treatment of the proton-proton Coulomb force in elastic proton-deuteron Faddeev calculations

TL;DR

This paper introduces a new method to include the proton-proton Coulomb force in three-nucleon Faddeev calculations using a 3D screened Coulomb t-matrix, enabling direct computation of elastic proton-deuteron observables without renormalization.

Contribution

A novel approach employing a 3D screened Coulomb t-matrix to incorporate Coulomb effects in Faddeev calculations, avoiding renormalization.

Findings

Elastic pd observables can be obtained directly from the 3N amplitude.

The screening limit exists without renormalization for observables and the amplitude.

The method provides analytical and numerical validation for the approach.

Abstract

We propose a novel approach to incorporate the proton-proton (pp) Coulomb force into the three-nucleon (3N) Faddeev calculations. The main new ingredient is a 3-dimensional screened pp Coulomb t-matrix obtained by a numerical solution of the 3-dimensional Lippmann-Schwinger (LS) equation. We demonstrate numerically and provide analytical insight that the elastic proton-deuteron (pd) observables can be determined directly from the resulting on shell 3N amplitude increasing the screening radius. The screening limit exists without the need of renormalisation not only for observables but for the elastic pd amplitude itself.