Studies of the muon momentum calibration and performance of the ATLAS detector with pp collisions at √s=13 TeV

Abstract

This paper presents the muon momentum calibration and performance studies for the ATLAS detector based on the pp collisions data sample produced at s = 13 TeV at the LHC during Run 2 and corresponding to an integrated luminosity of 139 fb - 1 . An innovative approach is used to correct for potential charge-dependent momentum biases related to the knowledge of the detector geometry, using the Z→ μ+μ- resonance. The muon momentum scale and resolution are measured using samples of J/ ψ→ μ+μ- and Z→ μ+μ- events. A calibration procedure is defined and applied to simulated data to match the performance measured in real data. The calibration is validated using an independent sample of Υ → μ+μ- events. At the Z (J/ ψ) peak, the momentum scale is measured with an uncertainty at the 0.05% (0.1%) level, and the resolution is measured with an uncertainty at the 1.5% (2%) level. The charge-dependent bias is removed with a dedicated in situ correction for momenta up to 450 GeV with a precision better than 0.03 TeV - 1 .