$t\bar{t}b\bar{b}$ hadroproduction with massive bottom quarks with PowHel

G. Bevilacqua; M. V. Garzelli; A. Kardos

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arXiv · 1709.06915

$t\bar{t}b\bar{b}$ hadroproduction with massive bottom quarks with PowHel

G. Bevilacqua·M. V. Garzelli·A. Kardos

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Abstract

The associated production of top-antitop-bottom-antibottom quarks is a relevant irreducible background for Higgs boson analyses in the top-antitop-Higgs production channel, with Higgs decaying into a bottom-antibottom quark pair. We implement this process in the PowHel event generator, considering the bottom quarks as massive in all steps of the computation which involves hard-scattering matrix-elements in the 4-flavour number scheme combined with 4-flavour Parton Distribution Functions. Predictions with NLO QCD + Parton Shower accuracy, as obtained by PowHel + PYTHIA, are compared to those which resulted from a previous PowHel implementation with hard-scattering matrix-elements in the 5-flavour number scheme, considering as a baseline the example of a realistic analysis of top-antitop hadroproduction with additional $b$-jet activity, performed by the CMS collaboration at the Large Hadron Collider.

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G. Bevilacqua, M. V. Garzelli, A. Kardos. 2017-09-20. $t\bar{t}b\bar{b}$ hadroproduction with massive bottom quarks with PowHel. https://arxiv.org/abs/1709.06915

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