Determination of the number of $\psi^{\prime}$ event at BESIII

TL;DR

This paper reports the precise measurement of the total number of $\psi^{ ext{'}}$ events collected by the BESIII experiment in 2009, using inclusive hadronic event counting, with a focus on systematic uncertainties.

Contribution

It provides a systematic-error-based determination of $\psi^{ ext{'}}$ event count, improving the accuracy of data used for subsequent physics analyses.

Findings

Total $\psi^{ ext{'}}$ events: 106.41 million

Systematic error: 0.81%

Negligible statistical error

Abstract

The number of $\psp$ events accumulated by the BESIII experiment from March 3 through April 14, 2009, is determined by counting inclusive hadronic events. The result is $106.41\times(1.00\pm 0.81%)\times 10^{6} $. The error is systematic only; the statistical error is negligible.