Double chiral logarithms of Generalized Chiral Perturbation Theory for low-energy ππ scattering
نویسنده
چکیده
We express the two-massless-flavor Gell-Mann–Oakes–Renner ratio in terms of low-energy ππ observables, including the O(p) double chiral logarithms of generalized chiral perturbation theory. Their contribution is sizeable and tends to compensate the one from the single chiral logarithms. However it is not large enough to spoil the convergence of the chiral expansion.
منابع مشابه
ππ scattering, pion form factors and chiral perturbation theory
I discuss recent progress in our understanding of the ππ scattering amplitude at low energy thanks to the combined use of chiral perturbation theory and dispersion relations. I also comment on the criticism raised by Peláez and Ynduráin on this work.
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