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تسجيل مستخدم جديدPion-pion scattering and the timelike pion form factor from $N_{mathrm{f}} = 2+1$ lattice QCD simulations using the stochastic LapH method
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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 $m_{pi} = 240mathrm{MeV}$. 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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Progress in calculating scattering phase shifts on $N_f=2+1$ anisotropic clover Wilson lattices is described. The stochastic LapH method facilitates computations in large volumes and for light pion masses. Results for pion masses down to 240 MeV, keeping $m_pi L > 4$, are presented.
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