Search for excited electrons and muons in $\sqrt{s}$=8 TeV proton-proton collisions with the ATLAS detector
- Aad, Georges et al
- arXiv:1308.1364CERN-PH-EP-2013-131
| Acceptance times efficiency ($A\times \epsilon$) of the excited-lepton selection as a function of the excited-lepton mass ($m_\lstar$), evaluated for a compositeness scale of 5~\tev. The uncertainties correspond to the sum in quadrature of the statistical uncertainty and systematic uncertainties associated with the lepton and photon efficiencies. |
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| noimgData yields and background expectations in the control region and after the $Z$ veto. The \zpjet\ and $W+\gamma+\rm jets$ backgrounds are scaled as described in the text. The uncertainties shown are purely from MC statistics, except for \zpjet\ and $W+\gamma+\rm jets$ where the statistical uncertainty on the associated scale factor is reported. |
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| Distributions of the transverse momentum of the photon ($\ptgam$) for the electron~\ref{fig:photon_pt_e} and muon~\ref{fig:photon_pt_mu} channels, in the control region defined by the dilepton mass range $70<m_{\ell\ell} < 110$~\gev. The background uncertainty corresponds to the sum in quadrature of the statistical uncertainties and the uncertainty in the data-driven \zpjet\ normalization.Caption not extracted |
| Distributions of the $\ell\gamma$ invariant mass ($m_{\ell\gamma}$) for the electron~\ref{fig:eg-final} and muon~\ref{fig:mug-final} channels after requiring the dilepton mass to satisfy $m_{\ell\ell} > 110$~\gev. Combinations with both the leading and subleading leptons are shown. The binned results of exponential fits are used for all backgrounds. The background uncertainty corresponds to the sum in quadrature of the statistical and systematic uncertainties. The last bin contains the sum of all entries with $m_{\ell\gamma}> 875$~\gev. Signal predictions for three different values of the excited-lepton mass ($m_\lstar$) with a compositeness scale ($\Lambda$) of 10~\tev\ are also shown.Caption not extracted |
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| Distributions of the $\ell\ell\gamma$ invariant mass ($m_{\ell\ell\gamma}$) for the electron~\ref{fig:eeg-final} and muon~\ref{fig:mumug-final} channels after requiring the dilepton mass to satisfy $m_{\ell\ell} > 110$~\gev. The binned results of exponential fits are used for the \zpgam, \zpjet, \ttbar\ and $W+\gamma+\rm jets$ backgrounds. The background uncertainty combining the statistical and systematic uncertainties is displayed as the hatched area. The last bin contains the sum of all events with $m_{\ell\ell\gamma}> 1350$~\gev. Signal predictions for three different values of the excited-lepton mass ($m_\lstar$) with a compositeness scale ($\Lambda$) of 10~\tev\ are also shown.Caption not extracted |
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| Upper limits at 95\% CL on the cross section times branching ratio ($\sigma B$) as a function of the excited-lepton mass ($m_{\lstar}$), for the electron~\ref{fig:limits1d-e} and muon~\ref{fig:limits1d-mu} channels. LO signal predictions with uncertainties from renormalization and factorization scales and PDFs are shown for three different compositeness scales ($\Lambda$).Caption not extracted |
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| Exclusion limits in the compositeness scale ($\Lambda$) vs excited-lepton mass~($m_{\lstar}$) parameter space for the electron~\ref{fig:limits2d-e} and muon~\ref{fig:limits2d-mu} channels. The filled area is excluded at 95\% CL. No limits are set in the dark shaded region $m_{\lstar} > \Lambda$ where the model is not applicable.Caption not extracted |