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arXiv · 1309.5912

NLO matching for ttbb production with massive b-quarks

Fabio Cascioli·Philipp Maierhoefer·Niccolo Moretti·Stefano Pozzorini·Frank Siegert
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Abstract

Theoretical uncertainties in the simulation of ttbb production represent one of the main obstacles that still hamper the observation of Higgs-boson production in association with top-quark pairs in the H->bb channel. In this letter we present a next-to-leading order (NLO) simulation of ttbb production with massive b-quarks matched to the Sherpa parton shower. This allows one to extend NLO predictions to arbitrary ttbb kinematics, including the case where one or both b-jets arise from collinear g->bb splittings. We find that this splitting mechanism plays an important role for the ttH(bb) analysis.

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Fabio Cascioli, Philipp Maierhoefer, Niccolo Moretti, Stefano Pozzorini, Frank Siegert. 2014-06-04. NLO matching for ttbb production with massive b-quarks. https://doi.org/10.1016/j.physletb.2014.05.040

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