Expected Sensitivity in Light Charged Higgs Boson Searches for H⁺→τ⁺ν and H⁺→cs with Early LHC Data at the ATLAS Experiment

This page contains approved plots and results as they appear in the ATL-PHYS-PUB-2010-006 note. Only the note contains all the relevant information and should thus be consulted if one of the plots is used. Click on an image to download in eps format. Please contact the HSG Documentation manager if you find any errors on this page.

Figure 1 contains D0 and CDF results. If required, please retrieve up to date results from their respective publications.

Figure 1: The 95% confidence level upper limits on the branching ratio versus , assuming (left, CDF) and (right, D0) for the charged Higgs boson. The CDF study [7] used a dataset while the D0 study [8] used a dataset.

Figure 2: At left, the dijet mass templates (normalized to a unit area) for the reconstructed and bosons. At right, the dijet mass templates (normalized to a unit area) for and after fitting. In the fitted distributions, a cut was made on the of the dijet mass fitter at 10 and we require the reconstructed top top mass on the hadronic side to the smaller than 195GeV.

Figure 3: Example likelihood shape normalized to have maximum at 1 (solid line) and likelihood integral (dotted line) as a function of positive for one PE. In both cases the maximum value is normalised to one. The arrow shows the position of the 95% CL upper limit from this particular PE.

Figure 4: At left, an example likelihood shape for one PE before (solid line) and after (dotted line) systematic smearing. The solid and dotted arrows show the respective 95% CL upper limit on for each PE assuming a mass of 130GeV. The mean (solid line) is taken as the expected value given a null-Higgs hypotheis. The dotted and dashed lines show the values of which contain 68% and 95% of entries respectively.

Figure 5: Left, di-jet mass as a function of the number of additional vertices in the event. The linear fit was used to derive a correction to the jet energies. Right, mass template from SM background events after correction of the jet energies.

Figure 6: At left, the normalized distribution of final state electrons and muons in dilepton events, coming from (dotted line), (dashed line) and (full line). Note that only the normalized distribution associated to follows Equation (4). At right, generator-level distribution of the final state electrons and muons in dilepton events, assuming a correct assignment of the various decay products, in the SM (dashed line) and with a 130GeV charged Higgs boson in the top quark decays with = 17% (full line).

Figure 7: At left, the normalized distributions for (dotted line) and (full line). At right, generator-level distributions of the generalized transverse mass, assuming a correct assignment of the various decay products, in the SM (dashed line) and with a 130GeV charged Higgs boson in the top quark decays, with = 17% (full line).

Figure 8: Comparison of the and generalized transverse mass distributions, as obtained from the scaled MC samples and the TopMixing sample in the sideband (the and backgrounds are shown by the darker shaded histograms). Dilepton events were later added to the TopMixing sample, however this sideband is not sensitive to the signal.

Figure 9: Comparison of the and generalized transverse mass distributions, as obtained from the scaled MC samples (with no event) and the TopMixing sample in the sideband, however with no cut on .

Figure 10: Comparison of the distribution in the SM case (dashed line) and as obtained when assuming = 130GeV together with = 17% (filled histogram). All selection cuts are applied, except the one on .

Figure 11: Comparison of the generalized transverse mass distributions in the SM case (dashed line) and as obtained when assuming = 130GeV together with = 17% (filled histogram). All selection cuts are applied, except the one on .

Figure 12: Determination of the branching ratio upper limit with (dashed line) and without (solid line) systematic uncertainties, for a 130GeV charged Higgs boson.

Figure 13: Expected 95% CL upper limits for as a function of in ATLAS, using the early LHC data (i.e. and = 10TeV), in the (left) and (right) channels. Also shown for reference are the current Tevatron upper limits on . No pile-up is included here.