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arXiv · 0706.3026

Precise Determination of the I=2 pipi Scattering Length from Mixed-Action Lattice QCD

Silas R. Beane·Thomas C. Luu·Kostas Orginos·Assumpta Parreno·Martin J. Savage·Aaron Torok·Andre Walker-Loud
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Abstract

The I=2 pipi scattering length is calculated in fully-dynamical lattice QCD with domain-wall valence quarks on the asqtad-improved coarse MILC configurations (with fourth-rooted staggered sea quarks) at four light-quark masses. Two- and three-flavor mixed-action chiral perturbation theory at next-to-leading order is used to perform the chiral and continuum extrapolations. At the physical charged pion mass, we find m_pi a_pipi(I=2) = -0.04330 +- 0.00042, where the error bar combines the statistical and systematic uncertainties in quadrature.

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Silas R. Beane, Thomas C. Luu, Kostas Orginos, Assumpta Parreno, Martin J. Savage, Aaron Torok, Andre Walker-Loud. 2007-06-20. Precise Determination of the I=2 pipi Scattering Length from Mixed-Action Lattice QCD. https://doi.org/10.1103/physrevd.77.014505

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