Study of the rare decay $J/\psi \to e^{+}{e}^{-}\varphi$

Abstract

We study the decay process of $J/\psi \to e^{+}{e}^{-}\varphi$ where the relatively clean electromagnetic (EM) transitions appear at leading order at tree level while the hadronic contributions only emerge via hadronic loop transitions. We include the low-lying scalar $f_0(980)$ and pseudoscalar $\eta /{\eta }^{\prime }$ as the dominant contributions in the evaluation of the hadronic loop contributions. It is found that the hadronic effects are negligible comparing with the EM contributions. The decay width of $J/\psi \to e^{+}{e}^{-}\varphi$ is determined to be about $2.12\times 10^{-6}$ keV if there is no any other leading mechanism contributing, and this result will be tested by the BESIII experiment with a large data sample of $J/\psi$.

Comments: 8 pages, 2 figures