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arXiv · 1412.6681

Background to Higgs-boson searches from internal conversions of off-shell photons associated with $Z/\gamma ^*$-boson production at the LHC

Anatoli Fedynitch·Mieczyslaw Witold Krasny·Wiesław Płaczek
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Abstract

This paper presents the studies of the background contribution to the $H \rightarrow 4l$ searches originating from the processes of off-shell (virtual) photon emissions and their conversions into lepton pairs accompanying the production of $Z/ \gamma ^*$-bosons at the LHC. They extend the analyses of the irreducible background presented in the ATLAS and CMS Higgs papers by taking into account the emissions of off-shell photons by parton showers. Including these effects does not change significantly the Higgs-searches background level, provided that the transverse momentum of each of the final-state leptons is restricted to the range of $p_{T, l} > 7$ GeV. In the kinematical region extended towards lower lepton transverse momenta the parton-shower contribution becomes important. A measurement method for pinning down the parton-shower effects is proposed.

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Anatoli Fedynitch, Mieczyslaw Witold Krasny, Wiesław Płaczek. 2014-12-20. Background to Higgs-boson searches from internal conversions of off-shell photons associated with $Z/\gamma ^*$-boson production at the LHC. https://doi.org/10.5506/aphyspolb.46.983

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