اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدMeasurement of {boldmath $J/psitoXi(1530)^{-}barXi^{+}$} and evidence for the radiative decay {boldmath $Xi(1530)^{-}togammaXi^-$}
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The SU(3)-flavor violating decay $J/psitoXi(1530)^{-}barXi^{+}+c.c.$ is studied using $(1310.6pm7.0)times 10^{6} ~J/psi$ events collected with the BESIII detector at BEPCII and the branching fraction is measured to be ${cal{B}}(J/psitoXi(1530)^{-}barXi^{+}+c.c.)=(3.17pm0.02_{rm stat.}pm0.08_{rm syst.})times10^{-4}$. 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 $alpha=-0.21pm0.04_{rm stat.}pm0.06_{rm syst.}$. In addition, we report evidence for the radiative decay $Xi(1530)^{-}togammaXi^- $ with a significance of 3.9$sigma$, including the systematic uncertainties. The 90% confidence level upper limit on the branching fraction is determined to be $mathcal{B}(Xi(1530)^{-}togammaXi^- )leq3.7$%.
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