Searches for Beyond Standard Model Higgs Bosons in $pp$ collisions at $\sqrt{s} = 8$ and 13 TeV with the ATLAS detector

The searches for a Beyond Standard Model (BSM) heavy CP-odd Higgs boson $A$ decaying to $Zh$ in the context of two-Higgs-doublet models (2HDM), and Minimal Supersymmetric Standard Model (MSSM) neutral Higgs bosons $H/A$ decaying to a tau pair are presented. The search for the heavy CP-odd Higgs boson, $A$, is conducted through the $A \rightarrow Zh\rightarrow ll\tau_{lep}\tau_{had}$ decay channel using 20.3 fb$^{-1}$ of proton-proton collision data collected by the ATLAS detector at a center-of-mass of 8 TeV. The search for the neutral MSSM $H/A$ decaying to a tau pair in the lephad $b$-veto final state is done using 3.2 fb$^{-1}$ of protonproton collision data recorded by the ATLAS detector at a center-of-mass of 13 TeV. The observed data agrees with the Standard Model background prediction, and upper limits are set on cross-section times branching ratio of neutral BSM Higgs bosons.