Evidence for ψ′ Decays into γπ0 and γη

Résumé fourni par la source

The decays ${\ensuremath{\psi}}^{\ensuremath{'}}\ensuremath{\rightarrow}\ensuremath{\gamma}{\ensuremath{\pi}}^{0}$, $\ensuremath{\gamma}\ensuremath{\eta}$ and $\ensuremath{\gamma}{\ensuremath{\eta}}^{\ensuremath{'}}$ are studied using data collected with the BESIII detector at the BEPCII ${e}^{+}{e}^{\ensuremath{-}}$ collider. The processes ${\ensuremath{\psi}}^{\ensuremath{'}}\ensuremath{\rightarrow}\ensuremath{\gamma}{\ensuremath{\pi}}^{0}$ and ${\ensuremath{\psi}}^{\ensuremath{'}}\ensuremath{\rightarrow}\ensuremath{\gamma}\ensuremath{\eta}$ are observed for the first time with signal significances of $4.6\ensuremath{\sigma}$ and $4.3\ensuremath{\sigma}$, respectively. The branching fractions are determined to be $\mathcal{B}({\ensuremath{\psi}}^{\ensuremath{'}}\ensuremath{\rightarrow}\ensuremath{\gamma}{\ensuremath{\pi}}^{0})=(1.58\ifmmode\pm\else\textpm\fi{}0.40\ifmmode\pm\else\textpm\fi{}0.13)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}6}$, $\mathcal{B}({\ensuremath{\psi}}^{\ensuremath{'}}\ensuremath{\rightarrow}\ensuremath{\gamma}\ensuremath{\eta})=(1.38\ifmmode\pm\else\textpm\fi{}0.48\ifmmode\pm\else\textpm\fi{}0.09)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}6}$, and $\mathcal{B}({\ensuremath{\psi}}^{\ensuremath{'}}\ensuremath{\rightarrow}\ensuremath{\gamma}{\ensuremath{\eta}}^{\ensuremath{'}})=(126\ifmmode\pm\else\textpm\fi{}3\ifmmode\pm\else\textpm\fi{}8)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}6}$, where the first errors are statistical and the second ones systematic.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.