ALPGEN, a generator for hard multiparton processes in hadronic collisions

By M. Mangano, F. Piccinini, A. Polosa, M. Moretti, R. Pittau. 2002

199 citations recorded by the source corpus.

This paper presents a new event generator, ALPGEN, dedicated to the study of multiparton hard processes in hadronic collisions. The code performs, at the leading order in QCD and EW interactions, the calculation of the exact matrix elements for a large set of parton-level processes of interest in the study of the Tevatron and LHC data. The current version of the code describes the following final states: (W→f')Q+N jets (Q being a heavy quark, and f = l,q), with N ≤ 4;(Z/γ*→f)Q+N jets (f = l,ν), with N ≤ 4; W→f')+charm+N jets (f = l,q,N ≤ 5;W→f')+N jets (f = l,q and Z/γ*→f)+N jets (f = l,ν), with N ≤ 6; nW+mZ+lH+N jets, with n+m+l+N ≤ 8, N ≤ 3, including all 2-fermion decay modes of W and Z bosons, with spin correlations; Q+N jets, with t→bf' decays and relative spin correlations included where relevant, and N ≤ 6; QQ''+N jets, with Q and Q' heavy quarks (possibly equal) and N ≤ 4; HQ+N jets, with t→bf' decays and relative spin correlations included where relevant and N ≤ 4; N jets, with N ≤ 6. Parton-level events are generated, providing full information on their colour and flavour structure, enabling the evolution of the partons into fully hadronised final states.

Subfields: Nuclear and High Energy Physics

View Paper: https://www.semanticscholar.org/paper/b36d8c17670feadd19126266d38ca734b33542bf

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Citations in the corpus

• Jet energy measurement with the ATLAS detector in proton-proton collisions at sqrt(s) = 7 TeV (2011, background): “ALPGEN is a tree level matrix-element generator for hard multi-parton processes (2 → n) in hadronic collisions [60].”
• A comprehensive approach to new physics simulations (2009, unknown): “At the matrix-element level, these include the development of general purpose event generators, such as COMPHEP/CALCHEP [4–6], MADGRAPH/MADEVENT [7–10], SHERPA [11, 12], as well as high efficiency multiparton generators which go beyond the usual Feynman diagram techniques, such as WHIZARD [13], ALPG”
• HERWIG 6: an event generator for hadron emission reactions with interfering gluons (including supersymmetric processes) (2001, methodology): “ need the options we have not yet supported please let us know. It should also be noted that while the interface has been tested with Standard Model processes, for example all the processes in ALPGEN [91], it is less well tested for SUSY processes. 9.2 CIRCE Simulation of beamstrahlung is now availa”
• Jet energy measurement and its systematic uncertainty in proton–proton collisions at $$\sqrt{s}=7$$s=7 TeV with the ATLAS detector (2015, methodology): “13) [37] is used to produce Z -jet events, interfaced to Herwig (version 6.”
• Measurement of inclusive jet and dijet cross sections in proton-proton collisions at 7 TeV centre-of-mass energy with the ATLAS detector (2010, methodology): “8.3 Event generator models The contributions to the JES uncertainty from the fragmentation and underlying event models and parameters of the MC event generator are obtained using samples generated with ALPGEN + HERWIG + JIMMY (which has a different matrix element, parton shower, hadronisation model ”
• Tuning PYTHIA 8.1: the Monash 2013 tune (2014, methodology): “Especially in the latter context of matrix-element matching, we expect that in many cases PYTHIA 8 will be used together with codes such as ALPGEN [127], MADGRAPH [128], aMCatNLO [129], or POWHEG [130], either using the matching algorithms of those programs themselves, or via any of PYTHIA’s several”
• Simulation of LHC events on a millions threads (2015, methodology): “14) [1], was chosen for this study because it is one of the largest sources of W/Z+jet events.”
• Measurement of the photon identification efficiencies with the ATLAS detector using LHC Run-1 data (2016, methodology): “= μ with each of the following three event generators: POWHEGinterfacedtoPYTHIA8;ALPGEN[38]interfaced to HERWIG [39] and JIMMY [40] for showering, hadronisa-tion and modelling of the underlying event; and SHERPA.”
• UFO - The Universal FeynRules Output (2011, background): “ties in the field of Monte Carlo simulations have been rather intense over the last fifteen years, resulting in many advances in the field. Automated tree-level matrix-element generators, such as Alpgen [1], Comix [2], CompHep/CalcHep [3,4,5], Helac [6], Herwig [7,8], MadGraph/MadEvent[9,10,11,12,13], ”
• Search for new phenomena in final states with large jet multiplicities and missing transverse momentum using sqrt(s)=7 TeV pp collisions with the ATLAS detector (2011, methodology): “The contribution in each SR is calculated from the corresponding CR t ¯ tj,p (with the same j, p ) in each case using a transfer factor evaluated using ALPGEN [18] v2.”
• Scattering amplitudes from unitarity-based reduction algorithm at the integrand-level (2010, background): “ becomes mandatory. Leading order (LO) processes are the core of well-established multi-purpose event generators like MadGraph MadEvent [1–3], CompHEP-CalcHEP [4,5], SHERPA [6,7], WHIZARD [8], ALPGEN [9], and HELAC [10,11], whereas a variety of processes computed at NLO are currently implemented in ”
• Jet energy resolution in proton-proton collisions at sqrt(s) = 7 TeV recorded in 2010 with the ATLAS detector (2012, background): “ALPGEN is a tree-level matrix element generator for hard multi-parton processes (2 → n) in hadronic collisions [31].”