Confirmation of theY(4260)resonance production in initial state radiation

Abstract

Using $13.3{\mathrm{fb}}^{-1}$ of $e^{+}{e}^{-}$ collision data taken in the ${\rm Y}(1S-4S)$ region with the CLEO III detector at the CESR collider, a search has been made for the new resonance $Y(4260)$ recently reported by the BABAR Collaboration. The production of $Y(4260)$ in initial state radiation (ISR), and its decay into ${\pi }^{+}{\pi }^{-}J/\psi$, are confirmed. A good quality fit to our data is obtained with a single resonance. We determine $M(Y(4260))=({4284}_{-16}^{+17}(\mathrm{stat})\pm 4(\mathrm{syst}))\mathrm{MeV}/c^2$, $\Gamma (Y(4260))=({73}_{-25}^{+39}(\mathrm{stat})\pm 5(\mathrm{syst}))\mathrm{MeV}/c^2$, and ${\Gamma }_{ee}(Y(4260))\times \mathcal{B}(Y(4260)\to {\pi }^{+}{\pi }^{-}J/\psi )=({8.9}_{-3.1}^{+3.9}(\mathrm{stat})\pm 1.8(\mathrm{syst}))\mathrm{eV}/c^2$.