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arXiv · 1402.3991

The nucleon mass and pion-nucleon sigma term from a chiral analysis of Nf = 2+1 lattice QCD world data

L. Alvarez-Ruso·T. Ledwig·J. Martin-Camalich·M. J. Vicente Vacas
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Abstract

Fits of the p^4 covariant SU(2) baryon chiral perturbation theory to lattice QCD nucleon mass data from several collaborations for 2 and 2+1 flavors are presented. We consider contributions from explicit Delta(1232) degrees of freedom, finite volume and finite spacing corrections. We emphasize here our Nf=2+1 study. We obtain low-energy constants of natural size that are compatible with the rather linear pion-mass dependence of the nucleon mass observed in lattice QCD. We report a value for the pion-nucleon sigma term of 41(5)(4) MeV for the 2 flavor case and 52(3)(8) MeV for 2+1 flavors.

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L. Alvarez-Ruso, T. Ledwig, J. Martin-Camalich, M. J. Vicente Vacas. 2014-02-17. The nucleon mass and pion-nucleon sigma term from a chiral analysis of Nf = 2+1 lattice QCD world data. https://doi.org/10.1051/epjconf%2F20146606001

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