Kittikul Kovitanggoona, Sung-Won Leea, Nural Akchurina, Jordan Damgova, Efe Yazganb, Lovedeep Sainic, Stephan Linnd, Luis Lebolod,

Shin-Shan Yue, Anil Singhe

aTexas Tech UniversitybUniversity of Ghent

cPanjab University, IndiadFlorida International University

eNational Central University, Taiwan

Z+jet Comparison to Theory

Part 1 Z(μμ) + jets

- Kinematics - MCFM

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Data sets Z(μμ) + jets Analysis is on 2011 (A +B) Rereco datasets in the total of 4.7 fb-1

DoubleMu_Run2011A-08Nov2011 DoubleMu_Run2011B-19Nov2011 Using the unprescaled Double Muons HLT MC + BG are Fall11 - MC

MADGRAPH POWHEG SHERPA MCFM

SHERPA weigh = LumiDATA

x X-sectionMC

/sumWeightMC

SHERPA histograms fill with h->Fill(variable,PU_weight*MC_weight)

Only shape comparison with MCFM

- Backgrounds are Fall11 MCDYToTauTauQCDWToMuNuTTWWWZZZ

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Di-muon properties for Z+njets

All MC give good agreement in Di-muon mass within 10% MADGRAPH give better agreement in Di-muon pT than POWHEG and SHERPA

Mμμ pTμμ

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Di-muon properties for Z+njets

Yμμ Φμμ

MADGRAPH , POWHEG, SHERPA give good agreement in Di-muon Y and Φ

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Inclusive Jet Multiplicity

All regions Central region

MADGRAPH provide good comparison in jet multiplicity but SHERPA and POWHEG does not

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Di-muon pT and Di-muon Yof

Z + 1 jet event

pTμμYμμ

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Jet pT and Jet YOf

Z + 1 jet event

pTjetYjet

MADGRAPH and POWHEG are good predictions of Z and jet in Z+1jet event SHERPA does bad prediction in kinematic of Z and jet

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MCFM Comparison Di-muon pT and Rapidity

YμμpTμμ

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MCFM Comparison Leading Jet pT and Rapidity

pTjet Yjet

Y shape comparisons to MCFM for both Z and jet show agreement within about 5-10% pT shape comparisons to MCFM for both Z and jet show agreement within about 20%

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MCFM Comparison Rapidity Sum and Difference between Z and Jet

0.5*(YZ+Yjet) 0.5*(YZ-Yjet)

SHERPA agrees better in term of rapidity sum and rapidity difference than MADGRAPH

Part 2 Z(ee) + jets

- Kinematic https://indico.cern.ch/getFile.py/accesscontribId=4&resId=0&materialId=slides&confId=176821

- MCFM

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Data sets Z(ee) + jets

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MCFM Comparison Di-muon pT and Rapidity

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MCFM Comparison Leading Jet pT and Rapidity

Y shape comparisons to MCFM for jet show agreement within about 10% but not bad for Z pT shape comparisons to MCFM for both Z and jet show agreement within about 20%

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MCFM Comparison Rapidity Sum and Difference between Z and Jet

0.5*(YZ+Yjet) 0.5*(YZ-Yjet)

SHERPA agrees better in term of rapidity sum and rapidity difference than MADGRAPH as we see in Z(μμ) + jet

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Conclusions

MC generations has their own Pros and Cons MADGRAPH

Better agreements in overall kinematics both Z and jets Angular variable (rapidity) between Z and jet is not good agreement

POWHEG Good prediction on Z (muons) In term of jet, only give good prediction up to 1 jet but not rapidity

SHERPA Better agreement in angular variable (rapidity) in Z+1jet Not so good prediction in term of other variables

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Conclusions

Madgraph, Sherpa, and MCFM all agree to within 5-20% of the data for pT and Y distributionsSherpa agrees better with data only for the rapidity sum and rapidity difference, but not good particularly for jet pt and jet y, and Z pT ΔY and ΣY should de-correlate matrix elements from PDF'S, but correlations persist. Madgraph agrees with NLO QCD (MCFM) Sherpa agrees with the data shape but normalization is wrong** The main difference between Sherpa and Madgraph is the method of matching patron showers to matrix elements to avoid double counting of jets.

Madgraph uses MLM Sherpa uses CKKW

**This statements is consistent with the D0 Result   PhysLett b682(2010) p370-380]  D0 did not have MadGraph

Ongoing: We are preparing CMS AN 12-037 It would be interesting to see ΔY for photons vs MADGRAPH and SHERPA

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Back Up

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Z(mumu) + jets Selections

The Muon Cuts are1. Muons are both Tracker muons and Global Muons but used Global muons variables 2. Opposite charge dimuon3. Muon pT > 20 GeV4. Muon isolationR03.sumPt < 35. Muon |eta| < 2.16. | Muon dxy(beamSport.position)| < 0.27. Muon ID

- Number of valid Pixel hits ≥ 1- Number of valid Tracker hits > 10- normChi2 < 10- Number of valid Muon hits ≥ 1

AK5 PFJet

- These jets are from the Z mass window events (76<Zmass<106)- We cleaned the jets from muons with DeltaR jet and muon > 0.5- The cut is jets pT > 30 GeV- Central region |jet eta|<2.4

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Z(ee) + jets Selections

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Z(ee) + jets Selections

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Di-muon pT and Di-muon YOf

Z + 2 jet event

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First Jet pT and First Jet YOf

Z + 2 jet event

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Second Jet pT and Second Jet YOf

Z + 2 jet event

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MEDGRAPHGeneration Variables

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#*********************************************************************# PDF CHOICE: this automatically fixes also alpha_s and its evol. *#********************************************************************* 'cteq6l1' = pdlabel ! PDF set #*********************************************************************# Renormalization and factorization scales *#********************************************************************* F = fixed_ren_scale ! if .true. use fixed ren scale F = fixed_fac_scale ! if .true. use fixed fac scale 91.1880 = scale ! fixed ren scale 91.1880 = dsqrt_q2fact1 ! fixed fact scale for pdf1 91.1880 = dsqrt_q2fact2 ! fixed fact scale for pdf2 1 = scalefact ! scale factor for event-by-event scales#*********************************************************************# Matching - Warning! ickkw > 0 is still beta#********************************************************************* 1 = ickkw ! 0 no matching, 1 MLM, 2 CKKW matching 1 = highestmult ! for ickkw=2, highest mult group 1 = ktscheme ! for ickkw=1, 1 Durham kT, 2 Pythia pTE 1 = alpsfact ! scale factor for QCD emission vx F = chcluster ! cluster only according to channel diag T = pdfwgt ! for ickkw=1, perform pdf reweighting#*********************************************************************# #**********************************# BW cutoff (M+/-bwcutoff*Gamma)#********************************** 15 = bwcutoffF = cut_decays ! Apply decays to products

#******************* # Running parameters#******************* # #*********************************************************************# Tag name for the run (one word) *#********************************************************************* 'Zjets' = run_tag ! name of the run #*********************************************************************# Run to generate the grid pack *#********************************************************************* .false. = gridpack !True = setting up the grid pack#*********************************************************************# Number of events and rnd seed *#********************************************************************* 100000 = nevents ! Number of unweighted events requested 0 = iseed ! rnd seed (0=assigned automatically=default))#*********************************************************************# Collider type and energy *#********************************************************************* 1 = lpp1 ! beam 1 type (0=NO PDF) 1 = lpp2 ! beam 2 type (0=NO PDF) 3500 = ebeam1 ! beam 1 energy in GeV 3500 = ebeam2 ! beam 2 energy in GeV#*********************************************************************# Beam polarization from -100 (left-handed) to 100 (right-handed) *#********************************************************************* 0 = polbeam1 ! beam polarization for beam 1 0 = polbeam2 ! beam polarization for beam 2

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SHERPAGeneration Variables

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import FWCore.ParameterSet.Config as cmssource = cms.Source("EmptySource")generator = cms.EDFilter("SherpaGeneratorFilter", maxEventsToPrint = cms.untracked.int32(0), filterEfficiency = cms.untracked.double(1.0), crossSection = cms.untracked.double(-1), Path = cms.untracked.string('SherpaRun'), PathPiece = cms.untracked.string('SherpaRun'), ResultDir = cms.untracked.string('Result'), default_weight = cms.untracked.double(1.0), SherpaParameters = cms.PSet(parameterSets = cms.vstring( "Run"), Run = cms.vstring( "(run){", " EVENTS = 1000;", " EVENT_MODE = HepMC;", " # avoid comix re-init after runcard modification", " WRITE_MAPPING_FILE 3;", "}(run)", "(beam){", " BEAM_1 = 2212; BEAM_ENERGY_1 = 3500.;", " BEAM_2 = 2212; BEAM_ENERGY_2 = 3500.;", "}(beam)", "(processes){", " Process 93 93 -> 90 90 93{4};", " Order_EW 2;", " Enhance_Factor 2 {3};", " Enhance_Factor 35 {4};", " Enhance_Factor 40 {5};", " Enhance_Factor 50 {6};", " CKKW sqr(20./E_CMS);", " Integration_Error 0.02 {5,6};", " End process;", "}(processes)", "(selector){", " Mass 90 90 50. E_CMS;", "}(selector)", "(me){", " ME_SIGNAL_GENERATOR = Internal Comix", " EVENT_GENERATION_MODE = Unweighted;", "}(me)", "(mi){", " MI_HANDLER = Amisic # None or Amisic", "}(mi)" ), ))ProductionFilterSequence = cms.Sequence(generator)

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MCFMGeneration Variables

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[General options to specify the process and execution Z+1j=41,Z+2j=44]41 [nproc]'tota' [part 'lord','real' or 'virt','tota']'ex_cal' ['runstring']7000d0 [sqrts in GeV]+1 [ih1 =1 for proton and -1 for antiproton]+1 [ih2 =1 for proton and -1 for antiproton]120d0 [hmass]1.0d0 [scale:QCD scale choice]1.0d0 [facscale:QCD fac_scale choice]'m(34)' [dynamicscale].false. [zerowidth].false. [removebr]10 [itmx1, number of iterations for pre-conditioning]400000 [ncall1]10 [itmx2, number of iterations for final run]400000 [ncall2]1089 [ij].false. [dryrun].true. [Qflag].true. [Gflag]

[Heavy quark masses]172.5d0 [top mass]4.75d0 [bottom mass]1.5d0 [charm mass]

[Pdf selection]'ctq61.00' [pdlabel]4 [NGROUP, see PDFLIB]46 [NSET - see PDFLIB]mstw2008nlo90cl.LHgrid [LHAPDF group]0 [LHAPDF set]

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POWHEGGeneration Variables

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<LesHouchesEvents version="1.0"><!--file generated with POWHEG-BOX version 1.0Input file powheg.input contained:! Z production parametervdecaymode 2 !(1:leptonic decay, 2:muonic decay, 3: tauonic decay,...) numevts 10000000 ! number of events to be generatedih1 1 ! hadron 1 (1 for protons, -1 for antiprotons)ih2 1 ! hadron 2 (1 for protons, -1 for antiprotons)ndns1 131 ! pdf set for hadron 1 (mlm numbering)ndns2 131 ! pdf set for hadron 2 (mlm numbering)ebeam1 3500d0 ! energy of beam 1ebeam2 3500d0 ! energy of beam 2 ! To be set only if using LHA pdfslhans1 10800 ! pdf set for hadron 1 (LHA numbering)lhans2 10800 ! pdf set for hadron 2 (LHA numbering) ! To be set only if using different pdf sets for the two incoming hadrons! QCDLambda5 0.25 ! for not equal pdf sets

! Parameters to allow or not the use of stored datause-old-grid 1 ! if 1 use old grid if file pwggrids.dat is present (<> 1 regenerate)use-old-ubound 1 ! if 1 use norm of upper bounding function stored in pwgubound.dat, if present; <>

ncall1 100000 ! number of calls for initializing the integration griditmx1 5 ! number of iterations for initializing the integration gridncall2 100000 ! number of calls for computing the integral and finding upper bounditmx2 5 ! number of iterations for computing the integral and finding upper boundfoldcsi 1 ! number of folds on csi integrationfoldy 1 ! number of folds on y integrationfoldphi 1 ! number of folds on phi integrationnubound 20000 ! number of bbarra calls to setup norm of upper bounding functionicsimax 1 ! <= 100, number of csi subdivision when computing the upper boundsiymax 1 ! <= 100, number of y subdivision when computing the upper boundsxupbound 2d0 ! increase upper bound for radiation generation

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! OPTIONAL PARAMETERS

ptsqmin 0.8 ! (default 0.8 GeV) minimum pt for generation of radiationcharmthr 1.5 ! (default 1.5 GeV) charm treshold for gluon splittingbottomthr 5.0 ! (default 5.0 GeV) bottom treshold for gluon splittingcharmthrpdf 1.5 ! (default 1.5 GeV) pdf charm tresholdbottomthrpdf 5.0 ! (default 5.0 GeV) pdf bottom treshold

#renscfact 1d0 ! (default 1d0) ren scale factor: muren = muref * renscfact#facscfact 1d0 ! (default 1d0) fac scale factor: mufact = muref * facscfact#ptsupp 0d0 ! (default 0d0) mass param for Born suppression factor (generation cut) If < 0 su#bornonly 0 ! (default 0) if 1 do Born only#smartsig 1 ! (default 1) remember equal amplitudes (0 do not remember)#withsubtr 0 ! (default 1) subtract real counterterms (0 do not subtract)#withdamp 1 ! (default 0, do not use) use Born-zero damping factortestplots 1 ! (default 0, do not) do NLO and PWHG distributions#hfact 100d0 ! (default no dumping factor) dump factor for high-pt radiation: > 0 dumpfac=h**2#testsuda 1 ! (default 0, do not test) test Sudakov form factor#radregion 1 ! (default all regions) only generate radiation in the selected singular region

iseed 0019 ! initialize random number sequence#rand1 -1 ! initialize random number sequence#rand2 -1 ! initialize random number sequence

#iupperisr 1 ! (default 1) choice of ISR upper bounding functional form#iupperfsr 2 ! (default 2) choice of FSR upper bounding functional form

#pdfreweight 1 ! (default 0) write extra pdf infos on LHEF

#manyseeds 1 ! (default 0) allow for the generation of different statistically independent samples (

sthw2 0.2312 ! sin**2 theta wmasswindow_low 28.529817249118306 ! M Z > Zmass - masswindow low * Zwidthmasswindow_high 2768.84113497916 ! M Z < Zmass + masswindow high * Zwidthrunningscale 1 ! choice for ren and fac scales in Bbar integration Z ! 0: fixed scale M ! 1: running scale inv mass ZEnd of powheg.input content