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arXiv · hep-ph/9902437

The Mesonic Chiral Lagrangian of Order $p^6$

Johan Bijnens·Gilberto Colangelo·Gerhard Ecker
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Abstract

We construct the effective chiral Lagrangian for chiral perturbation theory in the mesonic even-intrinsic-parity sector at order $p^6$. The Lagrangian contains 112 in principle measurable + 3 contact terms for the general case of $n$ light flavours, 90+4 for three and 53+4 for two flavours. The equivalence between equations of motion and field redefinitions to remove spurious terms in the Lagrangians is shown to all orders in the chiral expansion. We also discuss and implement other methods for reducing the number of terms to a minimal set.

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Johan Bijnens, Gilberto Colangelo, Gerhard Ecker. 1999-04-09. The Mesonic Chiral Lagrangian of Order $p^6$. https://doi.org/10.1088/1126-6708%2F1999%2F02%2F020

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