Search for charged Higgs bosons decaying into top and bottom quarks at $\sqrt{s}$ = 13 TeV with the ATLAS detector
JHEP 1811 (2018) 085
The collaboration

Abstract (data abstract)
CERN-LHC. A search for charged Higgs bosons heavier than the top quark and decaying via $H^\pm\to tb$ is presented. The dataset analysed corresponds to 36.1 fb$^{-1}$ of $pp$ collisions at $\sqrt{s}=13$ TeV and was recorded with the ATLAS detector at the LHC in 2015 and 2016. The production of a charged Higgs boson in association with a top quark and a bottom quark, $pp \to tbH^\pm$, is explored in the mass range from $m_{H^\pm}=200$ to $2000$ GeV using multi-jet final states with one or two electrons or muons. Events are categorised according to the multiplicity of jets and how likely these are to have originated from hadronisation of a bottom quark. Multivariate techniques are used to discriminate between signal and background events. No significant excess above the background-only hypothesis is observed and exclusion limits are derived for the production cross-section times branching ratio of a charged Higgs boson as a function of its mass, which range from 2.9 pb at $m_{H^\pm} = 200$ GeV to 0.070 pb at $m_{H^\pm} = 2000$ GeV. The results are interpreted in two benchmark scenarios of the Minimal Supersymmetric Standard Model.