# Development and validation of HERWIG 7 tunes from CMS underlying-event measurements

Published on Apr 12, 2021in European Physical Journal C4.389
· DOI :10.1140/EPJC/S10052-021-08949-5
Albert M Sirunyan178
Estimated H-index: 178
(Yerevan Physics Institute),
Rudolf Fruehwirth77
Estimated H-index: 77
(Yerevan Physics Institute)
+ 2410 AuthorsKevin Sung171
Estimated H-index: 171
(NU: Northwestern University)
Sources
Abstract
This paper presents new sets of parameters (“tunes”) for the underlying-event model of the \${\textsc {herwig}} \,7 event generator. These parameters control the description of multiple-parton interactions (MPI) and colour reconnection in {\textsc {herwig}} \,7 , and are obtained from a fit to minimum-bias data collected by the CMS experiment at \sqrt{s}=0.9 , 7, and 13 \,\text {Te}\text {V} . The tunes are based on the NNPDF 3.1 next-to-next-to-leading-order parton distribution function (PDF) set for the parton shower, and either a leading-order or next-to-next-to-leading-order PDF set for the simulation of MPI and the beam remnants. Predictions utilizing the tunes are produced for event shape observables in electron-positron collisions, and for minimum-bias, inclusive jet, top quark pair, and Z and W boson events in proton-proton collisions, and are compared with data. Each of the new tunes describes the data at a reasonable level, and the tunes using a leading-order PDF for the simulation of MPI provide the best description of the data.
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References53
#1Albert M Sirunyan (Yerevan Physics Institute)H-Index: 178
#2R. Erbacher (UC Davis: University of California, Davis)H-Index: 8
Last. Kevin SungH-Index: 171
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New sets of CMS underlying-event parameters (“tunes”) are presented for the pythia8 event generator. These tunes use the NNPDF3.1 parton distribution functions (PDFs) at leading (LO), next-to-leading (NLO), or next-to-next-to-leading (NNLO) orders in perturbative quantum chromodynamics, and the strong coupling evolution at LO or NLO. Measurements of charged-particle multiplicity and transverse momentum densities at various hadron collision energies are fit simultaneously to determine the paramet...
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BMWFW and FWF (Austria); FNRS and FWO (Belgium); CNPq, CAPES, FAPERJ, FAPERGS, and FAPESP (Brazil); MES (Bulgaria); CERN; CAS, MoST, and NSFC (China); COLCIENCIAS (Colombia); MSES and CSF (Croatia); RPF (Cyprus); SENESCYT (Ecuador); MoER, ERC IUT, and ERDF (Estonia); Academy of Finland, MEC, and HIP (Finland); CEA and CNRS/IN2P3 (France); BMBF, DFG, and HGF (Germany); GSRT (Greece); NKFIA (Hungary); DAE and DST (India); IPM (Iran); SFI (Ireland); INFN (Italy); MSIP and NRF (Republic of Korea); M...
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V. B., N. H., J. R., L. R. and E. S. are supported by an European Research Council Starting Grant “PDF4BSM”. R. D. B. and L. D. D. are supported by the UK STFC grants ST/L000458/1 and ST/P000630/1. L. D. D. is supported by the Royal Society, Wolfson Research Merit Award, grant WM140078. S. F. is supported by the European Research Council under the Grant Agreement 740006NNNPDFERC-2016-ADG/ERC-2016-ADG. E. R. N. is supported by the UK STFC grant ST/M003787/1. S. C. is supported by the HICCUP ERC C...
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