Dalitz plot analysis for the $\eta'\to\eta\pi\pi$ decay at GlueX

The study of the decay $\eta'\to\eta\pi\pi$ is interesting in many ways. First, the decay can be used to analyze the properties of the resonances $f_0(500)$ (or $\sigma$), where the scalar resonances contribution is predominant even if the decay is thought to be dominated by the contributions of the $a_0$ resonance. Second, the study of the $\eta'\to\eta\pi\pi$ decay may supply information to test predictions from $\chi PT$. Last, it offers the opportunity to constrain $\eta\pi$ scattering. In this talk, we report the progress in the analysis of the Dalitz plot for photoproduced $\eta'$, $\gamma p \to p \eta'$, for the decay channel $\eta'\to\eta\pi\pi$ using data obtained from the GlueX experiment in Hall D at Jefferson Laboratory.