Study of the rare decay $J/\psi \to 2\gamma+hadrons$ at the BESIII

TL;DR

This paper investigates the rare decay process of the $J/\psi$ particle into two photons and hadrons at BESIII, calculating main contributions, analyzing background processes, and demonstrating the potential for experimental measurement.

Contribution

The study provides the first detailed calculation of the $J/\psi \to 2\gamma + hadrons$ decay process and assesses its observability at BESIII.

Findings

Signal-to-background ratio can reach 1.24 with optimized criteria.

The decay process has a sufficiently large signal for experimental detection.

Distributions of signal and background are presented for analysis.

Abstract

Two-photon radiative decay process $J/\psi \to 2\gamma+hadrons$ is studied, and the main contribution processes $J/\psi \to 2\gamma + g g g$ and $J/\psi \to 2\gamma + q \bar{q}$ are calculated. With the specific condition at the BESIII, this rare decay process and the main background process $e^{+} e^{-} \to \gamma \gamma + hadrons (q \bar{q})$ are investigated. The results show that the ratio of signal to background can reach 1.24 with the optimized selection criteria at the BESIII. In addition, a few distributions of the signal and background are presented. All the results show that the signal is large enough to be measured in the experiment.