Measurements of Higgs boson production cross-section and $CP$ violation in the $H \to \tau \tau$ decay channel with the ATLAS detector

The $H \to \tau \tau$ decay is an important decay mode of the Higgs boson as it allows to measure directly the Higgs coupling to fermions. This paper presents the measurement of the $H \to \tau \tau$ cross-section and a test of $CP$ invariance in the Higgs boson production performed in the same channel. The results achieved using the data collected by the ATLAS experiment during the Run 1 of the LHC (2011– 2012), corresponding to 20 fb$^{-1}$, are shown and future perspectives for the Run 2 are described as well.