Relativistic baryon-baryon interactions in chiral perturbation theory

TL;DR

This paper explores leading order baryon-baryon interactions using covariant chiral perturbation theory, achieving good agreement with experimental phase shifts and scattering data in different strangeness sectors.

Contribution

It demonstrates the effectiveness of covariant baryon chiral perturbation theory at leading order in describing baryon-baryon interactions, comparable to higher-order and phenomenological models.

Findings

Good description of $np$ phase shifts for $J\,\leq\,1$

Accurate fit to hyperon-nucleon scattering data

Comparable results to NLO heavy baryon approach

Abstract

We report on the recent studies of leading order baryon-baryon interactions in covariant baryon chiral perturbation theory. In the strangeness $S=0$ sector, one can achieve a rather good description of the Nijmegen $np$ phase shifts with angular momenta $J\leq 1$, particularly the $^1S_0$ and $^3P_0$ partial waves, comparable with the next-to-leading order (NLO) heavy baryon approach. In the strangeness $S=-1$ hyperon-nucleon sector, the best fit of the 36 scattering data is similar to the sophisticated phenomenological models and the NLO heavy baryon approach.