Search for the reaction channel $e^+e^- \rightarrow \eta_c\eta \pi^+\pi^-$ at center-of-mass energies from 4.23 to 4.60 GeV

TL;DR

This study searches for the specific reaction $e^+e^- ightarrow ext{eta}_c ext{eta} ext{pi}^+ ext{pi}^-$ at energies 4.23 to 4.60 GeV using BESIII data, but finds no evidence of the process and sets upper limits on cross sections.

Contribution

First search for the reaction at these energies with detailed upper limits, expanding knowledge of charmonium-related processes in this energy range.

Findings

No signal observed in the eta_c mass region.

Upper limits on cross sections range from 6.2 to 27.6 pb.

Provides constraints for theoretical models of charmonium production.

Abstract

Using data collected with the BESIII detector operating at the Beijing Electron Positron Collider, we search for the process $e^+e^-\rightarrow \eta_c\eta \pi^+\pi^-$. The search is performed using five large data sets recorded at center-of-mass energies of 4.23, 4.26, 4.36, 4.42, and 4.60 GeV. The $\eta_c$ meson is reconstructed in 16 exclusive decay modes. No signal is observed in the $\eta_c$ mass region at any center-of-mass energy. The upper limits on the reaction cross sections are determined to be 6.2, 10.8, 27.6, 22.6 and 23.7 pb at the 90% confidence level at the center-of-mass energies listed above.