Study of $\eta (1475)$ and $X(1835)$ in radiative $J/\psi$ decays to $\gamma \varphi$

BESIII Collaboration, M. Ablikim, M. N. Achasov +428

The decay $J/\psi \to \gamma \gamma \varphi$ is studied using a sample of $1.31\times 10^9$ $J/\psi$ events collected with the BESIII detector. Two structures around 1475 MeV/c${}^2$ and 1835 MeV/c…