Accelerating LHC event generation with simplified pilot runs and fast PDFs

Abstract

Poor computing efficiency of precision event generators for LHC physics has become a bottleneck for Monte-Carlo event simulation campaigns. We provide solutions to this problem by focusing on two major components of general-purpose event generators: The PDF evaluator and the matrix-element generator. For a typical production setup in the ATLAS experiment, we show that the two can consume about 80% of the total runtime. Using NLO simulations of $pp\to {\ell }^{+}{\ell }^{-}+\text{jets}$ and $pp\to t\bar{t}+\text{jets}$ as an example, we demonstrate that the computing footprint of LHAPDF and Sherpa can be reduced by factors of order 10, while maintaining the formal accuracy of the event sample. The improved codes are made publicly available.

arXiv comment21 pages, 7 figures, 1 table, 2 listings

References in corpus (50)

• The automated computation of tree-level and next-to-leading order differential cross sections, and their matching to parton shower simulations
• Parton distributions for the LHC Run II
• MadGraph 5 : Going Beyond
• ALPGEN, a generator for hard multiparton processes in hadronic collisions
• Matching NLO QCD computations and parton shower simulations
• LHAPDF6: parton density access in the LHC precision era
• Scattering Amplitudes with Open Loops
• A parton shower algorithm based on Catani-Seymour dipole factorisation
• QCD Matrix Elements + Parton Showers
• An update on vector boson pair production at hadron colliders
• Comix, a new matrix element generator
• Event Generation with Sherpa 2.2
• QCD matrix elements + parton showers: The NLO case
• Vector boson pair production at the LHC
• A critical appraisal of NLO+PS matching methods
• OpenLoops 2
• General-purpose event generators for LHC physics
• An Automated Implementation of On-Shell Methods for One-Loop Amplitudes
• AMEGIC++ 1.0, A Matrix Element Generator In C++
• Correcting the Colour-Dipole Cascade Model with Fixed Order Matrix Elements
• GoSam-2.0: a tool for automated one-loop calculations within the Standard Model and beyond
• Helac-nlo
• RECOLA: REcursive Computation of One-Loop Amplitudes
• Automating dipole subtraction for QCD NLO calculations
• Recola2: REcursive Computation of One-Loop Amplitudes 2
• Precise Predictions for W + 3 Jet Production at Hadron Colliders
• Helac-Phegas: a generator for all parton level processes
• Recursive generation of one-loop amplitudes in the Standard Model
• NLO QCD matrix elements + parton showers in e+e- -> hadrons
• Numerical evaluation of virtual corrections to multi-jet production in massless QCD
• Hard photon production and matrix-element parton-shower merging
• A proposal for a standard interface between Monte Carlo tools and one-loop programs
• NLO QCD+EW predictions for V+jets including off-shell vector-boson decays and multijet merging
• On-the-fly reduction of open loops
• Next-to-Leading Order W + 5-Jet Production at the LHC
• Update of the Binoth Les Houches Accord for a standard interface between Monte Carlo tools and one-loop programs
• NGluon: A Package to Calculate One-loop Multi-gluon Amplitudes
• Challenges in Monte Carlo event generator software for High-Luminosity LHC
• Uncertainties in NLO + parton shower matched simulations of inclusive jet and dijet production
• Accelerating Monte Carlo event generation -- rejection sampling using neural network event-weight estimates
• Simulation of vector boson plus many jet final states at the high luminosity LHC
• A Neural Resampler for Monte Carlo Reweighting with Preserved Uncertainties
• Automated one-loop calculations with GoSam
• NLO electroweak corrections in extended Higgs Sectors with RECOLA2
• On the reduction of negative weights in MC@NLO-type matching procedures
• A matching of matrix elements and parton showers
• Jet cross sections at the LHC and the quest for higher precision
• Triple vector boson production through Higgs-Strahlung with NLO multijet merging
• Modelling and computational improvements to the simulation of single vector-boson plus jet processes for the ATLAS experiment
• Accelerating LHC phenomenology with analytic one-loop amplitudes: A C++ interface to MCFM

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• The $q_{\mathrm{T}}$ and $\Delta {\varphi }_{t\bar{t}}$ spectra in top-antitop hadroproduction at NNLL+NNLO: the interplay of soft-collinear resummation and Coulomb singularities
• Towards a Fully Automated Differential ${\text{NNLO}}_{\text{EW}}$ Generator for Lepton Colliders
• An Algorithm to Parallelise Parton Showers on a GPU
• Accelerating Berends-Giele recursion for gluons in arbitrary dimensions over finite fields
• Environmental sustainability in basic research: a perspective from HECAP+