Speaker
Jianyong Zhang
(IHEP, CAS)
Description
In order to obtain the most accurate mass of tau lepton using a limited amount of data at BESIII, we optimized the position and luminosity distribution of each energy point. Beam energy measurement system was built at BEPCII for minimizing the system error caused by energy uncertainty. About 140 pb-1 tau mass scan data was acquired in April this year, and preliminary measurement results is presented in this talk.
