Few nucleons scattering in pionless effective field theory

TL;DR

This paper uses pionless effective field theory at next-to-leading order to accurately predict low-energy scattering parameters for systems with up to four nucleons, confirming the necessity of a four-body force in certain channels.

Contribution

It provides a comprehensive NLO analysis of few nucleon scattering, demonstrating the theory's accuracy and clarifying the role of four-body forces in nuclear systems.

Findings

Accurate predictions of low-energy scattering parameters across all studied channels.

Confirmation that a four-body force is necessary at NLO in specific spin-isospin channels.

Theoretical results align well with experimental data and previous calculations.

Abstract

We present a comprehensive theoretical study of low-energy few nucleon scattering for systems with $A\leq 4$. To this end, we utilize pionless effective field theory, which we employ at next-to-leading order. We show that at this level the theory yields accurate predictions for the low-energy scattering parameters in all studied channels. These predictions are on par with the best experimental evaluations and the available theoretical calculations. We confirm the recent observation that a four-body force is needed at next-to-leading-order and find that for nuclear systems it only appears in a single spin-isospin channel.