Nucleon mass and sigma term from lattice QCD with two light fermion flavors Original Research Article

We analyze image nucleon mass data with respect to their dependence on the pion mass down to image and compare it with predictions from covariant baryon chiral perturbation theory (BChPT). A novel feature of our approach is that we fit the nucleon mass data simultaneously with the directly obtained pion–nucleon σ-term. Our lattice data below image is well described by image BChPT and we find image for the σ-term at the physical point. Using the nucleon mass to set the scale we obtain a Sommer parameter of image.