Lund multiplicity in QCD jets

Abstract

We compute the average Lund multiplicity of high-energy QCD jets. This extends an earlier calculation, done for event-wide multiplicity in $e^{+}{e}^{-}$ collisions [arxiv:2205.02861], to the large energy range available at the LHC. Our calculation achieves next-to-next-to-double logarithmic (NNDL) accuracy. Our results are split into a universal collinear piece, common to the $e^{+}{e}^{-}$ calculation, and a non-universal large-angle contribution. The latter amounts to 10-15% of the total multiplicity. We provide accurate LHC predictions by matching our resummed calculation to fixed-order NLO results and by incorporating non-perturbative corrections via Monte Carlo simulations. Including NNDL terms leads to a 50% reduction of the theoretical uncertainty, with non-perturbative corrections remaining below 5% down to transverse momentum scales of a few GeV. This proves the suitability of Lund multiplicities for robust theory-to-data comparisons at the LHC.

arXiv comment37 pages, 9 figures

References in corpus (54)

• The automated computation of tree-level and next-to-leading order differential cross sections, and their matching to parton shower simulations
• The anti-k_t jet clustering algorithm
• FastJet user manual
• Herwig 7.0 / Herwig++ 3.0 Release Note
• Better Jet Clustering Algorithms
• Event Generation with Sherpa 2.2
• Tuning PYTHIA 8.1: the Monash 2013 Tune
• Next-to-leading order calculation of three-jet observables in hadron-hadron collision
• Jet Substructure at the Large Hadron Collider: A Review of Recent Advances in Theory and Machine Learning
• Interleaved Parton Showers and Tuning Prospects
• The t-tbar cross-section at 1.8 and 1.96 TeV: a study of the systematics due to parton densities and scale dependence
• Jet Substructure at the Large Hadron Collider: Experimental Review
• Quark and Gluon Tagging at the LHC
• Jet Shapes with the Broadening Axis
• The PDF4LHC21 combination of global PDF fits for the LHC Run III
• Sudakov Safety in Perturbative QCD
• Parton showers beyond leading logarithmic accuracy
• Factorization for groomed jet substructure beyond the next-to-leading logarithm
• The Lund Jet Plane
• Jets with Variable R
• A first next-to-next-to-leading order study of three-jet production at the LHC
• On jet mass distributions in Z+jet and dijet processes at the LHC
• Casimir Meets Poisson: Improved Quark/Gluon Discrimination with Counting Observables
• Exposing the QCD Splitting Function with CMS Open Data
• Colour and logarithmic accuracy in final-state parton showers
• Leading-Color Two-Loop QCD Corrections for Three-Jet Production at Hadron Colliders
• The jet mass distribution after Soft Drop
• Accurate QCD predictions for heavy-quark jets at the Tevatron and LHC
• Soft drop groomed jet angularities at the LHC
• Jet Substructure Studies with CMS Open Data
• Spin correlations in final-state parton showers and jet observables
• Jet Angularities in Z+jet production at the LHC
• Associated jet and subjet rates in light-quark and gluon jet discrimination
• Phenomenology of jet angularities at the LHC
• The groomed and ungroomed jet mass distribution for inclusive jet production at the LHC
• PanScales parton showers for hadron collisions: formulation and fixed-order studies
• PanScales showers for hadron collisions: all-order validation
• Soft spin correlations in final-state parton showers
• Quarks and gluons in the Lund plane
• The soft drop groomed jet radius at NLL
• Computing $N$-subjettiness for boosted jets
• Calculating the primary Lund Jet Plane density
• Calculating the angle between jet axes
• A new tagger for hadronically decaying heavy particles at the LHC
• Lund and Cambridge multiplicities for precision physics
• Investigating the Topology Dependence of Quark and Gluon Jets
• QCD Jet Rates with the Inclusive Generalized kt Algorithms
• The Jet Shape at NLL${}^{\prime }$
• Resumming double non-global logarithms in the evolution of a jet
• Dynamical grooming meets LHC data
• QCD resummation for groomed jet observables at NNLL+NLO
• Jet mass distribution in Higgs/vector boson + jet events at hadron colliders with $k_t$ clustering
• The soft drop momentum sharing fraction $z_g$ beyond leading-logarithmic accuracy
• Jet energy drop

Cited by in corpus (5)

• Parton showering with higher-logarithmic accuracy for soft emissions
• Introduction to the PanScales framework, version 0.1
• Measurements of Lund subjet multiplicities in 13 TeV proton-proton collisions with the ATLAS detector
• Foundations of automatic feature extraction at LHC--point clouds and graphs
• 2B or not 2B, a study of bottom-quark-philic semi-visible jets