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arXiv · 1807.09477

In situ calibration of large-$R$ jet energy and mass in 13 TeV proton-proton collisions with the ATLAS detector

ATLAS Collaboration
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Abstract

The response of the ATLAS detector to large-radius jets is measured in situ using 36.2 fb$^{-1}$ of $\sqrt{s} = 13$ TeV proton-proton collisions provided by the LHC and recorded by the ATLAS experiment during 2015 and 2016. The jet energy scale is measured in events where the jet recoils against a reference object, which can be either a calibrated photon, a reconstructed $Z$ boson, or a system of well-measured small-radius jets. The jet energy resolution and a calibration of forward jets are derived using dijet balance measurements. The jet mass response is measured with two methods: using mass peaks formed by $W$ bosons and top quarks with large transverse momenta and by comparing the jet mass measured using the energy deposited in the calorimeter with that using the momenta of charged-particle tracks. The transverse momentum and mass responses in simulations are found to be about 2-3% higher than in data. This difference is adjusted for with a correction factor. The results of the different methods are combined to yield a calibration over a large range of transverse momenta ($p_{\rm T}$). The precision of the relative jet energy scale is 1-2% for $200~{\rm GeV} < p_{\rm T} < 2~{\rm TeV}$, while that of the mass scale is 2-10%. The ratio of the energy resolutions in data and simulation is measured to a precision of 10-15% over the same $p_{\rm T}$ range.

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ATLAS Collaboration. 2019-03-27. In situ calibration of large-$R$ jet energy and mass in 13 TeV proton-proton collisions with the ATLAS detector. https://doi.org/10.1140/epjc%2Fs10052-019-6632-8

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