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arXiv · 1905.10202

Pion scattering in the isospin I=2 channel from elongated lattices

C. Culver·M. Mai·A. Alexandru·M. Doring·F. X. Lee
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Abstract

Pion-pion elastic scattering in the isospin I=2 channel is investigated in two-flavor dynamical lattice QCD. Six ensembles are used with lattices elongated in one of the spatial dimensions at two quark masses corresponding to a pion mass of 315 MeV and 226 MeV. The energy of the low-lying states below the inelastic threshold are extracted in each case using the standard variational method.The extracted finite-volume spectrum is fitted by the inverse amplitude method simultaneously for both quark masses and extrapolated thereafter to the physical point. The resulting phase-shifts and scattering length are compared with those from experiment, leading-order chiral perturbation theory and other lattice studies. Our calculations match the experimental results.

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C. Culver, M. Mai, A. Alexandru, M. Doring, F. X. Lee. 2019-05-24. Pion scattering in the isospin I=2 channel from elongated lattices. https://doi.org/10.1103/physrevd.100.034509

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