Reassessing the $X(2370)$ in $J/ψ\toγK_S^0K_S^0π^0$ beyond the one-dimensional mass projections

Abstract: The BESIII Collaboration recently extracted the properties of the $X(2370)$ from a fit to the one-dimensional $K_S<sup>0K_S<sup>0π<sup>0$ invariant-mass spectrum in $J/ψ\toγK_S<sup>0K_S<sup>0π<sup>0$. The intermediate two-body structures visible in the mass correlations, including the $K_0<sup>*(1430)$ bands, require a coherent treatment of cross-channel interference when interpreting the enhancement near 2.3 GeV. We reassess the need for an additional $X(2370)$ contribution by fitting the published data using an effective coupled-channel framework. The three-body parent amplitude is parameterized by a $K$-matrix as the scattering among several quasi-two-body channels. The seven- and eight-bare-state models give similar mass distributions. Adding the eighth bare state lowers the Poisson deviance by 1.26% and produces an additional pole at $E=(2424-i\,149)$ MeV, substantially broader than the $X(2370)$ mass-width reference. This pole is model-dependent, and its identification with the $X(2370)$ is not clear. The present analysis does not establish the need for an additional $X(2370)$ contribution in $J/ψ\toγK_S<sup>0K_S<sup>0π<sup>0$, thereby weakening the flavor-singlet argument based on the suppression of $K^*\bar K$ relative to the total $K\bar Kπ$ contribution. A more comprehensive experimental amplitude analysis, incorporating coherent interference, mass and angular correlations, and detector effects across related decay channels, is needed to establish the role and decay properties of the $X(2370)$.