Low-energy p-d scattering and He-3 in pionless EFT

TL;DR

This paper uses pionless effective field theory to calculate low-energy proton-deuteron scattering and helium-3 binding energy differences, achieving good agreement with experimental data and exploring the role of Coulomb interactions.

Contribution

It provides next-to-next-to-leading order calculations for proton-deuteron scattering and analyzes Coulomb effects on helium-3 binding energy within pionless EFT.

Findings

Good agreement with phase shift analyses at low energies.

Calculated Coulomb contributions to helium-3 and tritium binding energy difference.

Explored implications for three-body force power counting.

Abstract

We calculate low-energy proton--deuteron scattering in the framework of pionless effective field theory. In the quartet channel, we calculate the elastic scattering phase shift up to next-to-next-to-leading order in the power counting. In the doublet channel, we perform a next-to-leading order calculation. We obtain good agreement with the available phase shift analyses down to the scattering threshold. The phase shifts in the region of non-perturbative Coulomb interactions are calculated by using an optimised integration mesh. Moreover, the Coulomb contribution to the 3He-3H binding energy difference is evaluated in first order perturbation theory. We comment on the implications of our results for the power counting of subleading three-body forces.