Search for Additional Heavy Neutral Higgs and Gauge Bosons with LHC Run 2 data in the $\tau\tau$ final state with the ATLAS detector

A search for heavy neutral Higgs and Z' bosons in the $\tau\tau$ channel is presented from data collected by the ATLAS detector in 2015 and 2016. The total data sample corresponds to an integrated luminosity of 36.1 fb$^{-1}$. The search is performed in two channels; both $\tau$ decay hadronically, or one $\tau$ decaying leptonically and one hadronically. Data are in good agreement with the standard model. Results are interpreted as limits on the cross section times branching fraction. Model-specific limits are presented in the $\tan\beta-m_{h}$ plane for two benchmark scenarios, hMSSM and $m_{h}^{mod+}$. For the Z' search results are interpreted using the Sequential Standard Model and non-universal G(221) model.