Measurement of the integrated luminosity of data samples collected during 2019-2022 by the Belle II experiment

TL;DR

This paper reports precise measurements of the integrated luminosity of data samples collected by the Belle II experiment from 2019 to 2022, using three independent methods to ensure accuracy and reliability.

Contribution

It introduces a comprehensive methodology combining Bhabha, digamma, and dimuon events to accurately determine integrated luminosity for Belle II data samples.

Findings

Total integrated luminosity is approximately 427.87 fb$^{-1}$.

Three independent methods yield consistent luminosity measurements.

Uncertainties are minimized through combined analysis.

Abstract

A series of data samples was collected with the Belle~II detector at the SuperKEKB collider from March 2019 to June 2022. We determine the integrated luminosities of these data samples using three distinct methodologies involving Bhabha ($e^+e^- \to e^+e^-(n\gamma)$), digamma ($e^+e^- \to \gamma\gamma(n\gamma)$), and dimuon ($e^+e^- \to \mu^+ \mu^- (n\gamma)$) events. The total integrated luminosity obtained with Bhabha, digamma, and dimuon events is ({426.88} $\pm$ 0.03 $\pm$ {2.61})~fb$^{-1}$, ({429.28} $\pm$ 0.03 $\pm$ {2.62})~fb$^{-1}$, and ({423.99} $\pm$ 0.04 $\pm$ {3.83})~fb$^{-1}$, where the first uncertainties are statistical and the second are systematic. The resulting total integrated luminosity obtained from the combination of the three methods is ({427.87 $\pm$ 2.01})~fb$^{-1}$.