1 import FWCore.ParameterSet.Config
as cms
3 herwig7LHESettingsBlock = cms.PSet(
4 hw_lhe_settings = cms.vstring(
5 '##################################################',
6 '# Example generator based on LHC parameters',
7 '# usage: Herwig read LHE.in',
8 '##################################################',
9 'read snippets/PPCollider.in',
10 '##################################################',
11 '# Technical parameters for this run',
12 '##################################################',
13 'cd /Herwig/Generators',
14 '#set EventGenerator:NumberOfEvents 10000000',
15 '#set EventGenerator:RandomNumberGenerator:Seed 31122001',
16 '#set EventGenerator:DebugLevel 0',
17 '#set EventGenerator:PrintEvent 10',
18 '#set EventGenerator:MaxErrors 10000',
19 '##################################################',
20 '# Create the Les Houches file handler and reader',
21 '##################################################',
22 'cd /Herwig/EventHandlers',
23 'library LesHouches.so',
24 '# create the event handler',
25 'create ThePEG::LesHouchesEventHandler LesHouchesHandler',
26 '# set the various step handlers',
27 'set LesHouchesHandler:PartonExtractor /Herwig/Partons/PPExtractor',
28 'set LesHouchesHandler:CascadeHandler /Herwig/Shower/ShowerHandler',
29 'set LesHouchesHandler:DecayHandler /Herwig/Decays/DecayHandler',
30 'set LesHouchesHandler:HadronizationHandler /Herwig/Hadronization/ClusterHadHandler',
31 '# set the weight option (e.g. for MC@NLO)',
32 'set LesHouchesHandler:WeightOption VarNegWeight',
33 '# set event hander as one to be used',
34 'set /Herwig/Generators/EventGenerator:EventHandler /Herwig/EventHandlers/LesHouchesHandler',
35 '# Set up an EMPTY CUTS object',
36 '# Normally you will have imposed any cuts you want',
37 '# when generating the event file and do not want any more',
38 '# in particular for POWHEG and MC@NLO you must not apply cuts on the',
40 'create ThePEG::Cuts /Herwig/Cuts/NoCuts',
41 '# You may wish to use the same PDF as the events were generated with',
42 'create ThePEG::LHAPDF /Herwig/Partons/LHAPDF ThePEGLHAPDF.so',
43 'set /Herwig/Partons/LHAPDF:PDFName NNPDF31_nnlo_as_0118',
44 'set /Herwig/Partons/LHAPDF:RemnantHandler /Herwig/Partons/HadronRemnants',
45 'set /Herwig/Particles/p+:PDF /Herwig/Partons/LHAPDF',
46 'set /Herwig/Particles/pbar-:PDF /Herwig/Partons/LHAPDF',
47 'set /Herwig/Partons/PPExtractor:FirstPDF /Herwig/Partons/LHAPDF',
48 'set /Herwig/Partons/PPExtractor:SecondPDF /Herwig/Partons/LHAPDF',
49 '# We would recommend the shower uses the default PDFs with which it was tuned.',
50 '# However it can be argued that the same set as for the sample should be used for',
51 '# matched samples, i.e. MC@NLO (and less so POWHEG)',
52 '#set /Herwig/Shower/ShowerHandler:PDFA /Herwig/Partons/LHAPDF',
53 '#set /Herwig/Shower/ShowerHandler:PDFB /Herwig/Partons/LHAPDF',
54 '# You can in principle also change the PDFs for the remnant extraction and',
55 '# multiple scattering. As the generator was tuned with the default values',
56 '# this is STRONGLY DISCOURAGED without retuning the MPI parameters',
57 '# create the reader and set cuts',
58 'create ThePEG::LesHouchesFileReader LesHouchesReader',
59 'set LesHouchesReader:FileName cmsgrid_final.lhe',
60 'set LesHouchesReader:AllowedToReOpen No',
61 'set LesHouchesReader:InitPDFs 0',
62 'set LesHouchesReader:Cuts /Herwig/Cuts/NoCuts',
63 '# option to ensure momentum conservation is O.K. due rounding errors (recommended)',
64 'set LesHouchesReader:MomentumTreatment RescaleEnergy',
66 'set LesHouchesReader:PDFA /Herwig/Partons/LHAPDF',
67 'set LesHouchesReader:PDFB /Herwig/Partons/LHAPDF',
68 '# if using BSM models with QNUMBER info',
69 '#set LesHouchesReader:QNumbers Yes',
70 '#set LesHouchesReader:Decayer /Herwig/Decays/Mambo',
71 '# and add to handler',
72 'insert LesHouchesHandler:LesHouchesReaders 0 LesHouchesReader',
73 '##################################################',
74 '# Shower parameters',
75 '##################################################',
76 '# normally, especially for POWHEG, you want',
77 '# the scale supplied in the event files (SCALUP)',
78 '# to be used as a pT veto scale in the parton shower',
79 'set /Herwig/Shower/ShowerHandler:MaxPtIsMuF Yes',
80 'set /Herwig/Shower/ShowerHandler:RestrictPhasespace Yes',
81 '# Shower parameters',
82 '# treatment of wide angle radiation',
83 'set /Herwig/Shower/PartnerFinder:PartnerMethod Random',
84 'set /Herwig/Shower/PartnerFinder:ScaleChoice Partner',
85 '# fix issue before 7.0.5 (not needed after this)',
86 'set /Herwig/Shower/GtoQQbarSplitFn:AngularOrdered Yes',
87 'set /Herwig/Shower/GammatoQQbarSplitFn:AngularOrdered Yes',
88 '# with MC@NLO these parameters are required for consistency of the subtraction terms',
89 '# suggested parameters (give worse physics results with POWHEG)',
90 '#set /Herwig/Shower/KinematicsReconstructor:InitialInitialBoostOption LongTransBoost',
91 '#set /Herwig/Shower/KinematicsReconstructor:ReconstructionOption General',
92 '#set /Herwig/Shower/KinematicsReconstructor:FinalStateReconOption Default',
93 '#set /Herwig/Shower/KinematicsReconstructor:InitialStateReconOption Rapidity',
94 '#set /Herwig/Shower/ShowerHandler:SpinCorrelations No',
95 '##################################################',
96 '# LHC physics parameters (override defaults here) ',
97 '##################################################',
98 '# e.g if different top mass used',
99 'set /Herwig/Particles/t:NominalMass 172.5',
100 '##################################################',
101 '# Save run for later usage with `Herwig run`',
102 '##################################################',
103 'cd /Herwig/Generators',
104 'saverun LHE EventGenerator' 
1.8.11
