Studies of the muon momentum calibration and performance of the ATLAS detector with $pp$ collisions at $\sqrt{s}$=13 TeV

TL;DR

This paper details the muon momentum calibration and performance assessment of the ATLAS detector at 13 TeV, achieving high precision in momentum scale and resolution corrections using various resonance samples.

Contribution

It introduces an innovative charge-dependent bias correction method and a calibration procedure that aligns simulated data with real detector performance.

Findings

Momentum scale uncertainty at 0.05% (Z peak) and 0.1% (J/psi peak)

Resolution uncertainty at 1.5% (Z) and 2% (J/psi)

Charge bias corrected with better than 0.03 TeV$^{-1}$ precision

Abstract

This paper presents the muon momentum calibration and performance studies for the ATLAS detector based on the $pp$ collisions data sample produced at $\sqrt{s}$=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 $Z \rightarrow \mu^{+}\mu^{-}$ resonance. The muon momentum scale and resolution are measured using samples of $J/\psi \rightarrow \mu^{+}\mu^{-}$ and $Z \rightarrow \mu^{+}\mu^{-}$ 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 $\Upsilon \rightarrow \mu^{+}\mu^{-}$ events. At the $Z$ ($J/\psi$) 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 {\em in situ} correction for momenta up to 450 GeV with a precision better than 0.03 TeV$^{-1}$.