Modelling and computational improvements to the simulation of single vector-boson plus jet processes for the ATLAS experiment

Abstract

This paper presents updated Monte Carlo configurations used to model the production of single electroweak vector bosons (W, Z/${\gamma }^{\ast }$) in association with jets in proton-proton collisions for the ATLAS experiment at the Large Hadron Collider. Improvements pertaining to the electroweak input scheme, parton-shower splitting kernels and scale-setting scheme are shown for multi-jet merged configurations accurate to next-to-leading order in the strong and electroweak couplings. The computational resources required for these set-ups are assessed, and approximations are introduced resulting in a factor three reduction of the per-event CPU time without affecting the physics modelling performance. Continuous statistical enhancement techniques are introduced by ATLAS in order to populate low cross-section regions of phase space and are shown to match or exceed the generated effective luminosity. This, together with the lower per-event CPU time, results in a 50% reduction in the required computing resources compared to a legacy set-up previously used by the ATLAS Collaboration. The set-ups described in this paper will be used for future ATLAS analyses and lay the foundation for the next generation of Monte Carlo predictions for single vector-boson plus jets production.

59 pages in total, author list starting page 44, 15 figures, 3 tables, published in JHEP 08 (2022) 089. All figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/PMGR-2021-01/

References in corpus (10)

• The automated computation of tree-level and next-to-leading order differential cross sections, and their matching to parton shower simulations
• A parton shower algorithm based on Catani-Seymour dipole factorisation
• Automation of next-to-leading order computations in QCD: the FKS subtraction
• Robust Independent Validation of Experiment and Theory: Rivet version 3
• Soft Photon Radiation in Particle Decays in SHERPA
• Electroweak corrections to W + jet hadroproduction including leptonic W-boson decays
• Electroweak Corrections in High Energy Processes using Effective Field Theory
• Accelerating Monte Carlo event generation -- rejection sampling using neural network event-weight estimates
• Search for squarks and gluinos in events with an isolated lepton, jets, and missing transverse momentum at $\sqrt{s}$ = 13 TeV with the ATLAS detector
• Measurement of the differential cross sections for the associated production of a W boson and jets in proton-proton collisions at sqrt(s) = 13 TeV

Cited by in corpus (13)

• Event Generators for High-Energy Physics Experiments
• Accelerating LHC event generation with simplified pilot runs and fast PDFs
• Unweighting multijet event generation using factorisation-aware neural networks
• Search for heavy Majorana or Dirac neutrinos and right-handed $W$ gauge bosons in final states with charged leptons and jets in $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector
• A simultaneous unbinned differential cross section measurement of twenty-four $Z$+jets kinematic observables with the ATLAS detector
• Search for a light charged Higgs boson in $t\to H^{\pm }b$ decays, with $H^{\pm }\to cs$, in $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector
• Electroweak, QCD and flavour physics studies with ATLAS data from Run 2 of the LHC
• Precise measurements of $W$- and $Z$-boson transverse momentum spectra with the ATLAS detector using $pp$ collisions at $\sqrt{s}=5.02$ TeV and $13$ TeV
• Accelerating multijet-merged event generation with neural network matrix element surrogates
• Measurement of the production of a $W$ boson in association with a charmed hadron in $pp$ collisions at $\sqrt{s}=13\mathrm{TeV}$ with the ATLAS detector
• Search for decays of the Higgs boson into scalar particles decaying into four or six $b$-quarks using $pp$ collisions at $\sqrt{s}=13\mathrm{TeV}$ with the ATLAS detector
• Improved reconstruction of highly boosted $\tau$-lepton pairs in the $\tau \tau \to (\mu {\nu }_{\mu }{\nu }_{\tau })(hadrons+{\nu }_{\tau })$ decay channels with the ATLAS detector
• Cross-section measurements for the production of a $W$-boson in association with high-transverse-momentum jets in $pp$ collisions at $\sqrt{s}$= 13 TeV with the ATLAS detector