Search for the decay $h_c\rightarrow\pi^0J/\psi$

TL;DR

This study searches for the decay $h_c\rightarrow\pi^0J/\psi$ using data from $e^+e^-$ collisions, finds no significant signal, and sets the first upper limits on its branching ratio, contributing to understanding charmonium decays.

Contribution

First upper limit established for the decay $h_c\rightarrow\pi^0J/\psi$, providing new constraints on charmonium decay modes.

Findings

No significant signal observed for $h_c\rightarrow\pi^0J/\psi$.

Upper limit on branching ratio: $7.5\times10^{-2}$.

Upper limit on branching fraction: $4.7\times10^{-4}$.

Abstract

A search for the decay $h_c\rightarrow\pi^0J/\psi$ is performed using a sample of $h_c$ produced in the reaction $e^+e^-\rightarrow\pi^+\pi^-h_c$. The data samples were collected with the BESIII detector at center-of-mass energies between 4.189 and 4.437 GeV, corresponding to a total integrated luminosity of 11 fb$^{-1}$. No significant signal is observed. Upper limits on the branching ratio $\mathcal{B}(h_c\rightarrow\pi^0J/\psi)/\mathcal{B}(h_c\rightarrow\gamma\eta_c\rightarrow\gamma K^+K^-\pi^0)$ and on the branching fraction $\mathcal{B}(h_c\rightarrow\pi^0J/\psi)$ are determined to be $7.5\times10^{-2}$ and $4.7\times10^{-4}$ at $90\%$ confidence level, respectively. The latter is derived from the former using the measured branching fraction of the normalization channel. This is the first determination of the upper limit of the decay $h_c\rightarrow\pi^0J/\psi$.