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The nucleon axial-vector coupling beyond one loop

Véronique Bernard·Ulf-G. Meißner
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Abstract

We analyze the nucleon axial-vector coupling to two loops in chiral perturbation theory. We show that chiral extrapolations based on this representation require lattice data with pion masses below 300 MeV.

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Véronique Bernard, Ulf-G. Meißner. 2006-05-14. The nucleon axial-vector coupling beyond one loop. https://doi.org/10.1016/j.physletb.2006.06.018

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