ISSN - 16741137, Chinese Physics C, 2016, vol. 41, 1, p. -
Determination of the number of J/ψ events with inclusive J/ψ decays
ï¿½ Article funded by SCOAP3 and published under licence by Chinese Physical Society and the Institute of High Energy Physics of the Chinese Academy of Sciences and the Institute of Modern Physics of the Chinese Academy of Sciences and IOP Publishing Ltd. A measurement of the number of J/ψ events collected with the BESIII detector in 2009 and 2012 is performed using inclusive decays of the J/ψ. The number of J/ψ events taken in 2009 is recalculated to be (223.7 ï¿½ 1.4) ï¿½ 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/ψ events taken in 2012 is determined to be (1086.9 ï¿½ 6.0) ï¿½ 10 6 . In total, the number of J/ψ events collected with the BESIII detector is measured to be (1310.6 ï¿½ 7.0) ï¿½ 10 6 , where the uncertainty is dominated by systematic effects and the statistical uncertainty is negligible.