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±...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±1.4）×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±6.0）×10^6. In total, the number of J/ψ events collected with the BESⅢ detector is measured to be（1310.6±7.0）×10^6, where the uncertainty is dominated by systematic effects and the statistical uncertainty is negligible.展开更多
基金Supported by National Key Basic Research Program of China(2015CB856700)National Natural Science Foundation of China(NSFC)(10805053,11125525,11175188,11235011,11322544,11335008,11425524)+15 种基金Chinese Academy of Sciences(CAS)Large-Scale Scientific Facility Programthe CAS Center for Excellence in Particle Physics(CCEPP)Collaborative Innovation Center for Particles and Interactions(CICPI)Joint Large-Scale Scientific Facility Funds of NSFC and CAS(11179007,U1232201,U1232107,U1332201)CAS(KJCX2-YW-N29,KJCX2-YW-N45)100 Talents Program of CAS,INPACShanghai Key Laboratory for Particle Physics and CosmologyGerman Research Foundation DFG(Collaborative Research Center CRC-1044)Istituto Nazionale di Fisica Nucleare,ItalyMinistry of Development of Turkey(DPT2006K-120470)Russian Foundation for Basic Research(14-07-91152)U.S.Department of Energy(DE-FG02-04ER41291,DE-FG02-05ER41374,DE-FG02-94ER40823,DESC0010118)U.S.National Science FoundationUniversity of Groningen(RuG)the Helmholtzzentrum fuer Schwerionenforschung GmbH(GSI),DarmstadtWCU Program of National Research Foundation of Korea(R32-2008-000-10155-0)
文摘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±1.4）×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±6.0）×10^6. In total, the number of J/ψ events collected with the BESⅢ detector is measured to be（1310.6±7.0）×10^6, where the uncertainty is dominated by systematic effects and the statistical uncertainty is negligible.
