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The anomalous chiral Lagrangian of order $p^6$

J. Bijnens·L. Girlanda·P. Talavera
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Abstract

We construct the effective chiral Lagrangian for chiral perturbation theory in the mesonic odd-intrinsic-parity sector at order $p^6$. The Lagrangian contains 24 in principle measurable terms and no contact terms for the general case of $N_f$ light flavours, 23 terms for three and 5 for two flavours. In the two flavour case we need a total of 13 terms if an external singlet vector field is included. We discuss and implement the methods used to reduce to a minimal set. The infinite parts needed for renormalization are calculated and presented as well.

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J. Bijnens, L. Girlanda, P. Talavera. 2005-10-26. The anomalous chiral Lagrangian of order $p^6$. https://doi.org/10.1007/s100520100887

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