2018/08/28 by Tomáš Ježo, Ježo, Tomáš
Computer Science · Physics and Astronomy · #Distributed and Parallel Computing Systems #FOS: Physical sciences #High Energy Physics - Phenomenology (hep-ph) #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies
paper · pdf · doi:10.48550/arxiv.1808.09311
openalex publication_date 2018/08/28 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Measurements of tt H production in the H→ bb channel depend in a critical way on the theoretical uncertainty associated with the irreducible QCD tt+b-jet background. We introduce a new pp→ ttbb POWHEG generator in the 4F scheme based on POWHEG-BOX-RES and on OpenLoops for fast evaluation of the scattering amplitudes. We present predictions and uncertainties for tt+b-jet observables at the 13 TeV LHC. We also consider theoretical uncertainties related to the POWHEG matching method and to the parton shower (PS) modelling, with emphasis on g→ bb splittings. In general, matching and shower uncertainties turn out to be remarkably small. This is confirmed by a consistent comparison against SHERPA+OpenLoops.