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Relationship between the quark condensate and low-energy Pi-Pi observables beyond O(p^4)

Luca Girlanda
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Abstract

The two-flavor Gell-Mann-Oakes-Renner ratio is expressed in terms of low-energy pi-pi observables including the O(p^6) double chiral logarithms, computed in Generalized Chiral Perturbation Theory. It is found that their contribution is important and tends to compensate the one from the single chiral logarithms.

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Luca Girlanda. 2000-07-29. Relationship between the quark condensate and low-energy Pi-Pi observables beyond O(p^4). https://arxiv.org/abs/hep-ph/0007348

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