Identification and energy calibration of hadronically decaying tau leptons with the ATLAS experiment in $pp$ collisions at $\sqrt{s}$=8 TeV

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This paper describes the trigger and offline reconstruction, identification and energy calibration algorithms for hadronic decays of tau leptons employed for the data collected from $pp$ collisions in 2012 with the ATLAS detector at the LHC center-of-mass energy $\sqrt{\mathrm{s}} = 8$ TeV.

• The performance of these algorithms is measured in most cases with $Z$ decays to tau leptons using the full 2012 dataset, corresponding to an integrated luminosity of 20.3 fb$^{-1}$.
• An uncertainty on the offline reconstructed tau energy scale of $2-4$%, depending on transverse energy and pseudorapidity, is achieved using two independent methods.
• The offline tau identification efficiency is measured with a precision of 2.5% for hadronically decaying tau leptons with one associated track, and of 4% for the case of three associated tracks, inclusive in pseudorapidity and for a visible transverse energy greater than $20$ GeV.