Search for a scalar partner of the $X(3872)$ via $\psi (3770)$ decays into $\gamma \eta {\eta }^{\prime }$ and $\gamma {\pi }^{+}{\pi }^{-}J/\psi$

BESIII Collaboration, M. Ablikim, M. N. Achasov +609

Using a data sample corresponding to an integrated luminosity of 2.93 fb${}^{-1}$ collected at a center-of-mass energy of 3.773~GeV with the BESIII detector at the BEPCII collider, w…