Effect of eigenstates on spectra in coupled-channel scattering with the chiral unitary model

Abstract

In recent years, as experimental data on the excited $\Xi(1620)$ and $\Xi(1690)$ states have accumulated, theoretical analyses based on chiral dynamics have also been actively pursued. In this study, we construct theoretical models within the chiral unitary approach to reproduce recent experimental data, and perform a model interpolation to examine the relationship between the poles appearing in different models. We then calculate the invariant mass spectra of the $\pi^+\Xi^-$ system in the $\Xi_c \to \pi\pi\Xi$ decay, using the scattering amplitudes obtained from each model, to investigate how the distinct pole structures influence the observable spectrum.