We study the quark-mass dependence of ω→3π decays, based on a
dispersion-theoretical framework. We rely on the quark-mass-dependent
scattering phase shift for the pion-pion P-wave extracted from unitarized
chiral perturbation theory. The dispersive representation then takes into
account the final-state rescattering among all three pions. The described
formalism may be used as an extrapolation tool for lattice QCD calculations of
three-pion decays, for which ω→3π can serve as a paradigm case.Comment: 12 pages, 8 figures; v2: added two references, version published in
EPJ