η′→ηππ decay as a probe of a possible lowest-lying scalar nonet

We study the ${\ensuremath{\eta}}^{\ensuremath{'}}\ensuremath{\rightarrow}\ensuremath{\eta}\ensuremath{\pi}\ensuremath{\pi}$ decay within an effective chiral Lagrangian approach in which the lowest lying scalar meson candidates $\ensuremath{\sigma}(560)$ and $\ensuremath{\kappa}(900)$ together with the ${f}_{0}(980)$ and ${a}_{0}(980)$ are combined into a possible nonet. We show that there exists a unique choice of the free parameters of this model which, in addition to fitting the $\ensuremath{\pi}\ensuremath{\pi}$ and $\ensuremath{\pi}K$ scattering amplitudes, well describes the experimental measurements for the partial decay width of ${\ensuremath{\eta}}^{\ensuremath{'}}\ensuremath{\rightarrow}\ensuremath{\eta}\ensuremath{\pi}\ensuremath{\pi}$ and the energy dependence of this decay. As a by-product, we estimate the ${a}_{0}(980)$ width to be 70 MeV, in agreement with a new experimental analysis.