اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدDetermination of the number of $J/psi$ events with inclusive $J/psi$ decays
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A measurement of the number of $J/psi$ events collected with the BESIII detector in 2009 and 2012 is performed using inclusive decays of the $J/psi$ . The number of $J/psi$ events taken in 2009 is recalculated to be $(223.7pm1.4)times 10^6$, which is in good agreement with the previous measurement, but with significantly improved precision due to improvements in the BESIII software. The number of $J/psi$ events taken in 2012 is determined to be $(1086.9pm 6.0)times 10^6$. In total, the number of $J/psi$ events collected with the BESIII detector is measured to be $(1310.6pm 7.0)times 10^6$, where the uncertainty is dominated by systematic effects and the statistical uncertainty is negligible.
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