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Power Counting Regime of Chiral Extrapolation and Beyond

Derek B. Leinweber·Anthony W. Thomas·Ross D. Young
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Abstract

Finite-range regularised (FRR) chiral effective field theory is presented in the context of approximation schemes ubiquitous in modern lattice QCD calculations. Using FRR techniques, the power-counting regime (PCR) of chiral perturbation theory can be estimated. To fourth-order in the expansion at the 1% tolerance level, we find m_π< 180 MeV for the PCR, extending only a small distance beyond the physical pion mass.

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Derek B. Leinweber, Anthony W. Thomas, Ross D. Young. 2005-10-12. Power Counting Regime of Chiral Extrapolation and Beyond. https://arxiv.org/abs/hep-lat/0510070

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