Determination of the number of J/$\ddot{I}ˆ$ events with J/$\ddot{I}ˆ$ \rightarrow decays

Abstract

The number of $J/\ddot{I}ˆ$ events collected with the BESIII detector at the BEPCII from June 12 to July 28, 2009 is determined to be $(225.3\pm 2.8)\times 10^6$ using $J/\ddot{I}ˆ\to inclusive$ events, where the uncertainty is the systematic error and the statistical one is negligible.

12 pages, 14 figures; (the paper has been received by the Chinese Physics C.)