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arXiv · hep-lat/0504022

Chiral and Continuum Extrapolation of Partially-Quenched Lattice Results

C. R. Allton·W. Armour·D. B. Leinweber·A. W. Thomas·R. D. Young
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Abstract

The vector meson mass is extracted from a large sample of partially quenched, two-flavor lattice QCD simulations. For the first time, discretisation, finite-volume and partial quenching artefacts are treated in a unified framework which is consistent with the low-energy behaviour of QCD. This analysis incorporates the leading infrared behaviour dictated by chiral effective field theory. As the two-pion decay channel cannot be described by a low-energy expansion alone, a highly-constrained model for the decay channel of the rho-meson is introduced. The latter is essential for extrapolating lattice results from the quark-mass regime where the rho is observed to be a physical bound state.

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C. R. Allton, W. Armour, D. B. Leinweber, A. W. Thomas, R. D. Young. 2005-10-11. Chiral and Continuum Extrapolation of Partially-Quenched Lattice Results. https://doi.org/10.1016/j.physletb.2005.09.020

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