2014/10/30 by Thibaut Métivet, Metivet, Thibaut
Physics and Astronomy · #Quantum Chromodynamics and Particle Interactions #Particle physics theoretical and experimental studies #High-Energy Particle Collisions Research
paper · pdf · doi:10.48550/arxiv.1410.8447
We use 2HEX smeared gauge configurations generated with an Nf=2+1 clover improved Wilson action to investigate ππ scattering in the ρ channel. The range of lattice spacings (0.054 to 0.12 fm) and space-like extents (32 and 48) allows us to extract the scattering parameters through the volume dependence of the ππ-state energies according to Lüscher's formalism. The pion masses (134 to 300 MeV) are light enough to allow the decay of the rho and the level repulsion observed indicates that our data are sensitive to the interaction. We analyse our data with a multi-channel GEVP variational formula. Our results are in good agreement with the experimental values and consistent with a weak pion mass dependence of the ρππ coupling constant.