# Extracting the σ-term from low-energy pion-nucleon scattering

@article{Elvira2017ExtractingT, title={Extracting the $\sigma$-term from low-energy pion-nucleon scattering}, author={Jacobo Ruiz de Elvira and Martin Hoferichter and Bastian Kubis and Ulf-G. Mei{\ss}ner}, journal={Journal of Physics G}, year={2017}, volume={45}, pages={024001} }

We present an extraction of the pion-nucleon (πN) scattering lengths from low-energy πN scattering, by fitting a representation based on Roy–Steiner equations to the low-energy data base. We show that the resulting values confirm the scattering-length determination from pionic atoms, and discuss the stability of the fit results regarding electromagnetic corrections and experimental normalization uncertainties in detail. Our results provide further evidence for a large πN σ-term, σπN = 58(5) MeV…

## 84 Citations

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