Jet energy scale measurements and their systematic uncertainties in proton-proton collisions at √𝑠 =13  TeV with the ATLAS detector

Abstract

Jet energy scale measurements and their systematic uncertainties are reported for jets measured with the ATLAS detector using proton-proton collision data with a center-of-mass energy of √𝑠=13  TeV, corresponding to an integrated luminosity of 3.2  fb−1 collected during 2015 at the LHC. Jets are reconstructed from energy deposits forming topological clusters of calorimeter cells, using the anti-𝑘𝑡 algorithm with radius parameter 𝑅 =0.4. Jets are calibrated with a series of simulation-based corrections and in situ techniques. In situ techniques exploit the transverse momentum balance between a jet and a reference object such as a photon, 𝑍 boson, or multijet system for jets with 20<𝑝T<2000  GeV and pseudorapidities of |𝜂| <4.5, using both data and simulation. An uncertainty in the jet energy scale of less than 1% is found in the central calorimeter region (|𝜂| <1.2) for jets with 100<𝑝T<500  GeV. An uncertainty of about 4.5% is found for low-𝑝T jets with 𝑝T=20  GeV in the central region, dominated by uncertainties in the corrections for multiple proton-proton interactions. The calibration of forward jets (|𝜂| >0.8) is derived from dijet 𝑝T balance measurements. For jets of 𝑝T=80  GeV, the additional uncertainty for the forward jet calibration reaches its largest value of about 2% in the range |𝜂| >3.5 and in a narrow slice of 2.2 <|𝜂| <2.4.