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arXiv · 1710.01901

The Pion Mass and Decay Constant at Three Loops in Two-Flavour Chiral Perturbation Theory

Johan Bijnens·Nils Hermansson Truedsson
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Abstract

A calculation of the pion mass and decay constant at NNNLO in two-flavour chiral perturbation theory is presented. The results are cross-checked by using both the exponential and square root parameterizations of the Goldstone matrix field, as well as by comparing to the known leading log coefficients of the two quantities. A small numerical study of the quark mass dependence is performed, and for a physical quark mass there is good agreement with lower order results.

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Johan Bijnens, Nils Hermansson Truedsson. 2017-10-05. The Pion Mass and Decay Constant at Three Loops in Two-Flavour Chiral Perturbation Theory. https://doi.org/10.1007/jhep11(2017)181

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