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arXiv · 0806.4863

Pion scattering in Wilson ChPT

Sinya Aoki·Oliver Bar·Benedikt Biedermann
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Abstract

We compute the scattering amplitude for pion scattering in Wilson chiral perturbation theory for two degenerate quark flavors. We consider two different regimes where the quark mass m is of order (i) aΛ_QCD^2 and (ii) a^2Λ_QCD^3. Analytic expressions for the scattering lengths in all three isospin channels are given. As a result of the O(a^2) terms the I=0 and I=2 scattering lengths do not vanish in the chiral limit. Moreover, additional chiral logarithms proportional to a^2\ln M_π^2 are present in the one-loop results for regime (ii). These contributions significantly modify the familiar results from continuum chiral perturbation theory.

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Sinya Aoki, Oliver Bar, Benedikt Biedermann. 2008-11-07. Pion scattering in Wilson ChPT. https://doi.org/10.1103/physrevd.78.114501

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