η'→ηππ decays in unitarized resonance chiral theory

We study the hadronic η'→ηππ decays within the framework of U(3)L⊗U(3)R Chiral Perturbation Theory including resonance states and the complete one-loop corrections. The amplitude is projected in partial waves and unitarized by means of the N / D method resumming both the important S- and D-wave ππ and the subleading S-wave πη final-state interactions. The participating scalar multiplet mass and coupling strengths are determined from fits to the Dalitz plot experimental data recently released by the A2 collaboration. As a byproduct of our analysis, the associated Dalitz-plot slope parameters are found to be a=-0.072(7)stat(8)syst,b=-0.052(1)stat(2)syst,d=-0.051(8)stat(6)syst, which lie in the ballpark of the current experimental and theoretical determinations.