Measurement of {\boldmath $J/\ddot{I}ˆ\to \hat{I}ž(1530{)}^{-}\bar{\hat{I}}{ž}^{+}$} and evidence for the radiative decay {\boldmath $\hat{I}ž(1530{)}^{-}\to {\hat{I}}^3\hat{I}{ž}^{-}$}

Abstract

The SU(3)-flavor violating decay $J/\ddot{I}ˆ\to \hat{I}ž(1530{)}^{-}\bar{\hat{I}}{ž}^{+}+c.c.$ is studied using $(1310.6\pm 7.0)\times 10^{6}J/\ddot{I}ˆ$ events collected with the BESIII detector at BEPCII and the branching fraction is measured to be $\mathcal{B}(J/\ddot{I}ˆ\to \hat{I}ž(1530{)}^{-}\bar{\hat{I}}{ž}^{+}+c.c.)=(3.17\pm 0.02_{stat.}\pm 0.08_{syst.})\times 10^{-4}$. This is consistent with previous measurements with an improved precision. The angular parameter for this decay is measured for the first time and is found to be $\hat{I}\pm =-0.21\pm 0.04_{stat.}\pm 0.06_{syst.}$. In addition, we report evidence for the radiative decay $\hat{I}ž(1530{)}^{-}\to {\hat{I}}^3\hat{I}{ž}^{-}$ with a significance of 3.9$\ddot{I}ƒ$, including the systematic uncertainties. The 90\% confidence level upper limit on the branching fraction is determined to be $\mathcal{B}(\hat{I}ž(1530{)}^{-}\to {\hat{I}}^3\hat{I}{ž}^{-})\le 3.7$\%.

10 pages, 7 figures