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arXiv · 1511.02351

Pion-pion scattering and the timelike pion form factor from $N_{\mathrm{f}} = 2+1$ lattice QCD simulations using the stochastic LapH method

John Bulava·Ben Hörz·Brendan Fahy·K. J. Juge·Colin Morningstar·Chik Him Wong
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Abstract

We report on progress applying the stochastic LapH method to estimate all-to-all propagators required in correlation functions of multi-hadron operators relevant for pion-pion scattering. Large-volume results for $I=2$ and $I=1$ pion-pion scattering phase shifts with good statistical precision are obtained from an $N_{\rm f} = 2+1$ anisotropic Wilson clover ensemble with $m_π = 240\mathrm{MeV}$. We also present a preliminary determination of the $I=1$ pion-pion scattering phase shift and timelike pion form factor on an isotropic $N_{\rm f}=2+1$ flavour ensemble generated by the Coordinated Lattice Simulation (CLS) community effort.

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John Bulava, Ben Hörz, Brendan Fahy, K. J. Juge, Colin Morningstar, Chik Him Wong. 2015-11-18. Pion-pion scattering and the timelike pion form factor from $N_{\mathrm{f}} = 2+1$ lattice QCD simulations using the stochastic LapH method. https://arxiv.org/abs/1511.02351

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