Search for the decay ${\eta }^{\prime }\to \gamma \gamma \eta$

M. Ablikim, M. N. Achasov, P. Adlarson +479

Using a data sample of $1.31\times 10^{9}J/\psi$ events collected with the BESIII detector, a search for ${\eta }^{\prime }\to \gamma \gamma \eta$ via $J/\psi \to \gamma {\eta }^{\prime }$ is performed for the first time. No significant $η…