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Abstract

Precision measurements of electron reconstruction, identifcation, and isolation efciencies and photon identifcation efciencies are presented. They use the full Run 2 data sample collected by the ATLAS experiment in pp collisions at a centre-of-mass energy of 13 TeV during the years 2015–2018, corresponding to an integrated luminosity of 139 fb−1 . The measured electron identifcation efciencies have uncertainties that are around 30%–50% smaller than the previous Run 2 results due to an improved methodology and the inclusion of more data. A better pile-up subtraction method leads to electron isolation efciencies that are more independent of the amount of pile-up activity. Updated photon identifcation efciencies are also presented, using the full Run 2 data. When compared to the previous measurement, a 30%–40% smaller uncertainty is observed on the photon identifcation efciencies, thanks to the increased amount of available data.