${\eta }^{\prime }\to \eta \pi \pi$ decays in unitarized resonance chiral theory

Sergi Gonzàlez-Solís, Emilie Passemar

We study the hadronic ${\eta }^{\prime }\to \eta \pi \pi$ decays within the framework of $U(3{)}_L\otimes U(3{)}_R$ Chiral Perturbation Theory including resonance states and the complete one-loop c…