A determination of the jet energy scale is presented using proton-proton collision data with a centre-ofmass energy of
SQUARE ROOT s = 13 TeV, corresponding to an integrated luminosity of 140 fb-1 collected using the ATLAS detector at the LHC. Jets are reconstructed using the ATLAS particleflow method that combines charged-particle tracks and topoclusters formed from energy deposits in the calorimeter cells.
The anti-kt jet algorithm with radius parameter R = 0.4 is used to define the jet.Novel jet energy scale calibration strategies developed for the LHC Run 2 are reported that lay the foundation for the jet calibration in Run 3. Jets are calibrated with a series of simulation-based corrections, including stateof- the-art techniques in jet calibration such as machine learning methods and novel in situ calibrations to achieve better performance than the baseline calibration derived using up to 81 fb-1 of Run 2 data. The performance of these new techniques is then examined in the in situ measurements by exploiting the transverse momentum balance between a jet and a reference object. The b-quark jet energy scale using particle flow jets is measured for the first time with around 1% precision using γ +jet events.