Studies of Tau-Lepton Polarisation in Decays of Higgs and Z Bosons with the ATLAS Experiment

The Tau-Lepton Polarisation is studied in Decays of 125 GeV Higgs and Z Bosons with regard to the separation power. Three di↵erent observables: the fraction of visible energy x, the charged energy asymmetry ⌥and the polarimetric vector h are discussed in this study. The analysis is based on Monte Carlo simulated proton-proton collisions at 8 TeV center-of-mass energy at LHC, collected by the ATLAS detector. Each variable is evaluated regarding the theoretical and observed separation power between tau leptons with positive and negative helicity, followed by the separation power between 125 GeV Higgs and Z Bosons.