Study of $e^{+}{e}^{-}\to {\rm Y}(1S,2S)\eta$ and $e^{+}{e}^{-}\to {\rm Y}(1S){\eta }^{\prime }$ at $\sqrt{s}=10.866$ GeV with the Belle detector

Belle Collaboration, E. Kovalenko, A. Garmash +179

We report the first observation of the processes $e^{+}{e}^{-}\to {\rm Y}(1S,2S)\eta$ at $\sqrt{s}=10.866$~GeV with a $10.2\sigma$ and $16.5\sigma$ significance respectively. The measured Born cross sec…