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arXiv · hep-ph/9508354

Baryon masses and pion-nucleon $σ$-term to second order in the quark masses

B. Borasoy·Ulf-G. Meißner
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Abstract

We analyze the octet baryon masses and the pion--nucleon $σ$--term in the framework of heavy baryon chiral perturbation theory. In contrast to previous investigations, we include {\it all} terms up-to-and-including quadratic order in the light quark masses. The pertinent low--energy constants are fixed from resonance exchange. This leaves as the only free parameter the baryon mass in the chiral limit, $\krig{m}$. We find $\krig{m} = 749 \pm 125$~MeV together with $σ_{πN} (0) = 48 \pm 10$ ~MeV. We discuss various implications of these results.

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B. Borasoy, Ulf-G. Meißner. 1995-08-24. Baryon masses and pion-nucleon $σ$-term to second order in the quark masses. https://doi.org/10.1016/0370-2693(95)01286-9

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