Measurement of the integrated luminosities of the data taken by BESIII at $\sqrt s=$ 3.650 and 3.773 GeV

TL;DR

This paper reports precise measurements of the integrated luminosities of data collected by the BESIII detector at specific energies, essential for accurate physics analyses.

Contribution

The paper provides the first detailed measurement of integrated luminosities at these energies using large angle Bhabha scattering events.

Findings

Integrated luminosity at 3.650 GeV: 44.49 pb^{-1}

Integrated luminosity at 3.773 GeV: 2916.94 pb^{-1}

Measurement uncertainties are well quantified

Abstract

Data sets were collected with the BESIII detector at the BEPCII collider at the center-of-mass energy of $\sqrt s =$ 3.650 GeV during May 2009 and at $\sqrt s=$ 3.773 GeV from January 2010 to May 2011. By analyzing the large angle Bhabha scattering events, the integrated luminosities of the two data sets are measured %at $\sqrt s=$ 3.650 and 3.773 GeV to be ($\rm 44.49\pm0.02\pm0.44$) $\rm pb^{-1}$ and ($\rm 2916.94\pm0.18\pm29.17$) $\rm pb^{-1}$, respectively, where the first error is statistical and the second error is systematic.