Search for charged Higgs bosons decaying into top and bottom quarks at $\sqrt{s}$ = 13 TeV with the ATLAS detector

The ATLAS collaboration Aaboud, Morad ; Aad, Georges ; Abbott, Brad ; et al.
JHEP 11 (2018) 085, 2018.
Inspire Record 1686365 DOI 10.17182/hepdata.83203

A search for charged Higgs bosons heavier than the top quark and decaying via $H^\pm \rightarrow tb$ is presented. The data 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, $pp \rightarrow tb H^\pm$, 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 fraction 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.

5 data tables match query

Expected and observed limits for the production of $H^{+} \to tb$ in association with a top quark and a bottom quark. The bands surrounding the expected limit show the 68% and 95% confidence intervals. The limits are based on the combination of the $\ell+$jets and $\ell\ell$ final states. Theory predictions are shown for three representative values of $\tan\beta$ in the $m_h^{\mathrm{mod-}}$ benchmark scenario. Uncertainties in the predicted $H^+$ cross-sections or branching ratios are not considered.

Expected and observed upper limits on $\tan\beta$ as a function of $m_{H^{+}}$ in the $m_h^{\mathrm{mod-}}$ scenario of the MSSM. Limits are shown for $\tan\beta$ values in the range of 0.5-60, where predictions are available from both scenarios. The bands surrounding the expected limits show the 68% and 95% confidence intervals. The limits are based on the combination of the $\ell+$jets and $\ell\ell$ final states. The production cross-section of $t\bar{t}H$ and $tH$, as well as the branching ratios of the $H$, are fixed to their SM values at each point in the plane. Uncertainties on the predicted $H^{+}$ cross-sections or branching ratios are not considered.

Expected and observed lower limits on $\tan\beta$ as a function of $m_{H^{+}}$ in the $m_h^{\mathrm{mod-}}$ scenario of the MSSM. Limits are shown for $\tan\beta$ values in the range of 0.5-60, where predictions are available from both scenarios. The bands surrounding the expected limits show the 68% and 95% confidence intervals. The limits are based on the combination of the $\ell+$jets and $\ell\ell$ final states. The production cross-section of $t\bar{t}H$ and $tH$, as well as the branching ratios of the $H$, are fixed to their SM values at each point in the plane. Uncertainties on the predicted $H^{+}$ cross-sections or branching ratios are not considered.

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Search for dijet resonances in events with an isolated charged lepton using $\sqrt{s} = 13$ TeV proton-proton collision data collected by the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abbott, Dale Charles ; et al.
JHEP 06 (2020) 151, 2020.
Inspire Record 1782373 DOI 10.17182/hepdata.94787

A search for dijet resonances in events with at least one isolated charged lepton is performed using $139~{\text{fb}}^{-1}$ of $\sqrt{s}=13$ TeV proton-proton collision data recorded by the ATLAS detector at the LHC. The dijet invariant-mass ($m_{jj}$) distribution constructed from events with at least one isolated electron or muon is searched in the region $0.22 < m_{jj} < 6.3$ TeV for excesses above a smoothly falling background from Standard Model processes. Triggering based on the presence of a lepton in the event reduces limitations imposed by minimum transverse momentum thresholds for triggering on jets. This approach allows smaller dijet invariant masses to be probed than in inclusive dijet searches, targeting a variety of new-physics models, for example ones in which a new state is produced in association with a leptonically decaying $W$ or $Z$ boson. No statistically significant deviation from the Standard Model background hypothesis is found. Limits on contributions from generic Gaussian signals with widths ranging from that determined by the detector resolution up to 15% of the resonance mass are obtained for dijet invariant masses ranging from 0.25 TeV to 6 TeV. Limits are set also in the context of several scenarios beyond the Standard Model, such as the Sequential Standard Model, a technicolor model, a charged Higgs boson model and a simplified Dark Matter model.

12 data tables match query

Observed and expected 95% credibility-level upper limits on the cross-section times acceptance times branching ratio for the techicolor model with production of $\rho_T$ decaying to $\pi_T W^{\pm}$. The table also shows the corresponding $1\sigma$ and $2\sigma$ bands for the expected limits. The limits are calculated using jets in events with at least one isolated lepton ($e$ or $\mu$) with $p_\text{T}^\ell \ge 60$ GeV.

Observed and expected 95% credibility-level upper limits on the cross-section times acceptance times branching ratio for $W' \to Z' W^{\pm}$ production in the Sequential Standard Model. The table also shows the corresponding $1\sigma$ and $2\sigma$ bands for the expected limits. The limits are calculated using jets in events with at least one isolated lepton ($e$ or $\mu$) with $p_\text{T}^\ell \ge 60$ GeV.

Observed and expected 95% credibility-level upper limits on the cross-section times branching ratio for the $tbH^+$ model. The table also shows the corresponding $1\sigma$ and $2\sigma$ bands for the expected limits. The limits are calculated using jets in events with at least one isolated lepton ($e$ or $\mu$) with $p_\text{T}^\ell \ge 60$ GeV.

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