Determination of the number of J/$\psi$ events with J/$\psi$ \rightarrow   decays
  The number of $J/\psi$ events collected with the BESIII detector at the BEPCII from June 12 to July 28, 2009 is determined to be $(225.3\pm2.8)\times10^{6}$ using $J/\psi \rightarrow inclusive$ events, where the uncertainty is the systematic error and the statistical one is negligible. 
BESIII collaboration
hep-ex