Chiral extrapolations of the ρ(770) meson in Nf=2+1 lattice QCD simulations

Recent Nf=2+1 lattice data for meson-meson scattering in the p-wave and with isospin I=1 are analyzed using a unitarized model inspired by chiral perturbation theory in the inverse-amplitude formulation for two and three flavors. Chiral extrapolations are performed that postdict phase shifts extracted from experiment quite well. In addition, the low-energy constants are compared to the ones from a recent analysis of Nf=2 lattice QCD simulations to check for the consistency of the hadronic model used here. Some inconsistencies are detected in the fits to Nf=2+1 data, in contrast to the previous analysis of Nf=2 data.