Searching for charmoniumlike states with hidden $s\bar{s}$

TL;DR

This paper explores the potential for kinematic effects, specifically anomalous triangle singularities, to mimic charmnium-like states with hidden s-sbar quark content in certain e+e- collision processes, challenging the resonance interpretation.

Contribution

It introduces a method to differentiate between genuine resonance states and kinematic singularities caused by rescattering effects in e+e- collisions.

Findings

Anomalous triangle singularities can produce resonance-like structures.

The positions of these singularities depend on the scattering kinematics.

This provides a criterion to distinguish kinematic effects from real particles.

Abstract

We investigate the processes $e^+e^-$$\to$$\gamma J/\psi\phi$, $\gamma J/\psi\omega$ and $\pi^0 J/\psi\eta$ to search for the charmnium-like states with hidden $s\bar{s}$, such as $Y(4140)$, $Y(4274)$, $X(4350)$ and $X(3915)$. These processes will receive contributions from the charmed-strange meson rescatterings. When the center-of-mass energies of the $e^+e^-$ scatterings are taken around the $D_{s0}(2317)D_s^{*}$, $D_{s1}(2460)D_s$ or $D_{s1}(2460)D_s^{*}$ threshold, the anomalous triangle singularities can be present in the rescattering amplitudes, which implies a non-resonance explanation about the resonance-like structures. The positions of the anomalous triangle singularities are sensitive to the kinematics, which offers us a criterion to distinguish the kinematic singularities from genuine particles.