Five-flavour scheme predictions for $t\bar{t}b\bar{b}$ at next-to-leading order accuracy

TL;DR

This paper presents NLO predictions for top quark pair production with bottom quarks at the LHC using the five-flavour scheme, employing advanced merging techniques and event generation enhancements.

Contribution

It introduces a novel approach combining the five-flavour scheme with FxFx merging for accurate $t\bar{t}b\bar{b}$ predictions at NLO, improving event selection efficiency.

Findings

Differences observed between five-flavour and four-flavour scheme predictions.

Enhanced bottom quark event generation increases selection efficiency.

NLO accuracy achieved with up to 2 jets in the merging scheme.

Abstract

We compute top quark pair production in association with a bottom quark pair at the LHC within the five-flavour scheme, matched to a parton shower, employing the FxFx merging scheme for $t\bar{t}+\textrm{jets}$ production with up to 2 jets at NLO accuracy. To enhance the selection efficiency for the events with $b$-jets within the inclusive five-flavour sample, we augment the generation probability of bottom quark flavours in the short-distance event generation. Our analysis reveals some differences from NLO predictions within the four-flavour scheme.