Predictions for Z -Boson Production in Association with a b -Jet at O(αs3)

R Gauld,I Majer,A Gehrmann–De Ridder,E W N Glover,A Huss

doi:10.1103/physrevlett.125.222002

Abstract

Precise predictions are provided for the production of a $\mathrm{Z}$-boson and a $\mathrm{b}$-jet in hadron-hadron collisions within the framework of perturbative QCD, at $\mathcal{O}(\alpha_s^3)$. To obtain these predictions we perform the first calculation of a hadronic scattering process involving the direct production of a flavoured-jet at next-to-next-to-leading order accuracy in massless QCD, and extend techniques to also account for the impact of finite heavy-quark mass effects. The predictions are compared to CMS data obtained in $\mathrm{pp}$ collisions at a centre-of-mass energy of $8~\mathrm{TeV}$, which are the most precise data from Run I of the LHC for this process, where a good description of the data is achieved. To allow this comparison we have performed an unfolding of the data, which overcomes the long-standing issue that the experimental and theoretical definitions of jet flavour are incompatible.

Highlights

Introduction.—The high-energy hadron collisions at the LHC provide an environment in which to search for signals of physics beyond-the-standard model, both through precision measurements of known processes as well as direct searches
We perform the first calculation of a hadronic scattering process involving the direct production of a flavored jet at next-to-nextto-leading-order accuracy in massless QCD and extend techniques to account for the impact of finite heavy-quark mass effects
Theoretical predictions for processes involving the direct production of a flavored jet in hadron-hadron scattering are currently limited to next-to-leading order (NLO) QCD accuracy interfaced to a parton shower (NLO þ PS) [4,5,6,7]

Summary

Introduction

Introduction.—The high-energy hadron collisions at the LHC provide an environment in which to search for signals of physics beyond-the-standard model, both through precision measurements of known processes as well as direct searches. We perform the first calculation of a hadronic scattering process involving the direct production of a flavored jet at next-to-nextto-leading-order accuracy in massless QCD and extend techniques to account for the impact of finite heavy-quark mass effects.

Results

Conclusion