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arXiv · 1902.10508

Flavor decomposition of the pion-nucleon $σ$-term

Daniel Severt·Ulf-G. Meißner·Jambul Gegelia
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Abstract

We re-analyze the flavor decomposition of the pion-nucleon $σ$-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.

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Daniel Severt, Ulf-G. Meißner, Jambul Gegelia. 2019-04-03. Flavor decomposition of the pion-nucleon $σ$-term. https://doi.org/10.1007/jhep03(2019)202

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