# Flavor decomposition of the pion-nucleon $\sigma$-term

## TL;DR

This paper re-analyzes the flavor decomposition of the pion-nucleon sigma-term using baryon chiral perturbation theory, finding a small strangeness content in the proton but with large uncertainties.

## Contribution

It provides a detailed re-analysis of the sigma-term's flavor decomposition at fourth order in chiral perturbation theory, including covariant and heavy baryon frameworks.

## Key findings

- Small strangeness content of the proton found
- Large uncertainties in the analysis
- Highlights need for lattice QCD calculations

## Abstract

We re-analyze the flavor decomposition of the pion-nucleon $\sigma$-term in the framework of baryon chiral perturbation to fourth order. We employ a covariant and the heavy baryon framework including also the low-lying decuplet. Using only continuum data, we find a small strangeness content of the proton. The uncertainties are, however, large and might be overcome by dedicated lattice QCD calculations.