Performance of the ATLAS muon triggers in Run 2

ATLAS Collaboration

doi:10.1088/1748-0221/15/09/p09015

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arXiv · 2004.13447

Performance of the ATLAS muon triggers in Run 2

ATLAS Collaboration

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Abstract

The performance of the ATLAS muon trigger system is evaluated with proton-proton ($pp$) and heavy-ion (HI) collision data collected in Run 2 during 2015-2018 at the Large Hadron Collider. It is primarily evaluated using events containing a pair of muons from the decay of $Z$ bosons to cover the intermediate momentum range between 25 GeV and 100 GeV. Overall, the efficiency of the single-muon triggers is about 68 % in the barrel region and 85% in the endcap region. The $p_{\text{T}}$ range for efficiency determination is extended by using muons from decays of $J/\psi$ mesons, $W$ bosons, and top quarks. The performance in HI collision data is measured and shows good agreement with the results obtained in $pp$ collisions. The muon trigger shows uniform and stable performance in good agreement with the prediction of a detailed simulation. Dedicated multi-muon triggers with kinematic selections provide the backbone to beauty, quarkonia, and low-mass physics studies. The design, evolution and performance of these triggers are discussed in detail.

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ATLAS Collaboration. 2020-04-28. Performance of the ATLAS muon triggers in Run 2. https://doi.org/10.1088/1748-0221/15/09/p09015

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