A Comprehensive Study of the Radiative Decays of $J/\psi$ and $\psi(2S)$ to Pseudoscalar Meson Pairs, and Search for Glueballs

TL;DR

This study analyzes radiative decays of $J/\psi$ and $\psi(2S)$ into pseudoscalar meson pairs, measuring branching fractions and searching for glueball states in specific mass ranges, providing insights into meson spectroscopy and glueball candidates.

Contribution

It provides the first comprehensive measurement of radiative decay branching fractions of $J/\psi$ and $\psi(2S)$ into pseudoscalar pairs and extends glueball searches to higher mass regions.

Findings

Measured branching fractions for multiple scalar and tensor resonances.

Identified potential glueball candidates among observed resonances.

Extended glueball search to masses between 2.5 and 3.3 GeV.

Abstract

Using 53 pb$^{-1}$ of $e^+e^-$ annihilation data taken at $\sqrt{s}=3.686$ GeV, a comprehensive study has been made of the radiative decays of samples of 5.1 million $J/\psi$ and 24.5 million $\psi(2S)$ into pairs of pseudoscalar mesons, $\pi^+\pi^-$, $\pi^0\pi^0$, $K^+K^-$, $K_S^0K_S^0$, and $\eta\eta$. Product branching fractions for the radiative decays of $J/\psi$ and $\psi(2S)$ to scalar resonances $f_0(1370,1500,1710,2100, \text{and} 2200)$, and tensor resonances $f_2(1270,1525, \text{and} 2230)$ have been determined, and are discussed in relation to predicted glueballs. For $\psi(2S)$ radiative decays the search for glueballs has been extended to masses between 2.5 GeV and 3.3 GeV.