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Two-point Functions at Two Loops in Three Flavour Chiral Perturbation Theory

Gabriel Amoros·Johan Bijnens·Pere Talavera
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Abstract

The vector and axial-vector two-point functions are calculated to next-to-next-to-leading order in Chiral Perturbation Theory for three light flavours. We also obtain expressions at the same order for the masses, $m_π^2$, $m_K^2$ and $m_η^2$, and the decay constants, $F_π$, $F_K$ and $F_η$. We present some numerical results after a simple resonance estimate of some of the new ${\cal O}(p^6)$ constants.

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Gabriel Amoros, Johan Bijnens, Pere Talavera. 1999-07-07. Two-point Functions at Two Loops in Three Flavour Chiral Perturbation Theory. https://doi.org/10.1016/s0550-3213(99)00674-4

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