Measurement of the $k_{\mathrm{t}}$ splitting scales in $Z\to \mathrm{\ell }\mathrm{\ell }$ events in $pp$ collisions at $\sqrt{s}=8$ TeV with the ATLAS detector

A measurement of the splitting scales occuring in the $k_{\mathrm{t}}$ jet-clustering algorithm is presented for final states containing a $Z$ boson. The measurement is done using 20.2 fb${}^{-1}$ of proton-proton collision data collected at a centre-of-mass energy of $\sqrt{s}=8$ TeV by the ATLAS experiment at the LHC in 2012. The measurement is based on charged-particle track information, which is measured with excellent precision in the $p_{\mathrm{T}}$ region relevant for the transition between the perturbative and the non-perturbative regimes. The data distributions are corrected for detector effects, and are found to deviate from state-of-the-art predictions in various regions of the observables.