Luminosities and energies of $e^+e^-$ collision data taken between $\sqrt{s}$=4.612 GeV and 4.946 GeV at BESIII

TL;DR

This paper reports on the BESIII experiment's collection of high-energy $e^+e^-$ collision data between 4.61 and 4.95 GeV, with precise measurements of energies and luminosities, enabling advanced studies of charmonium states and charmed-hadron decays.

Contribution

It introduces a novel method for measuring collision energies with high precision and provides highly accurate luminosity measurements for the BESIII data samples.

Findings

Collision energies measured with ~0.6 MeV precision

Luminosities measured with better than 1% accuracy

Data collected at the highest energies achieved by BEPCII

Abstract

From December 2019 to June 2021, the BESIII experiment collected about 5.85 fb$^{-1}$ of data at center-of-mass energies between 4.61 GeV and 4.95 GeV. This is the highest collision energy BEPCII has reached so far. The accumulated $e^+e^-$ annihilation data samples are useful for studying charmonium(-like) states and charmed-hadron decays. By adopting a novel method of analyzing the production of $\Lambda_{c}^{+}\bar{\Lambda}_{c}^{-}$ pairs in $e^+e^-$ annihilation, the center-of-mass energies are measured with a precision of $\sim$0.6 MeV. Integrated luminosities are measured with a precision of better than 1\% by analyzing the events of large-angle Bhabha scattering. These measurements provide important inputs to the analyses based on these data samples.