Rivet analyses
Measurements of angular distance and momentum ratio distributions in three-jet and Z + two-jet final states in pp collisions at 8 and 13 TeV
Experiment: CMS (LHC)
Inspire ID: 1847230
Status: VALIDATED
Authors: - cms-pag-conveners-smp@cern.ch - Hannes Jung - Hyunyong Kim - Olga Kodolova
References: - arXiv: 2102.08816 - Expt page: CMS-SMP-17-008 - EPJC (Submitted)
Beams: p+ p+
Beam energies: (4000.0, 4000.0); (6500.0, 6500.0)GeV
Run details: - QCD with pt>300 or Z -> mu+ mu-
Collinear (small-angle) and large-angle, as well as soft and hard radiations are investigated in three-jet and Z + two-jet events collected in proton-proton collisions at the LHC. The normalized production cross sections are measured as a function of the ratio of transverse momenta of two jets and their angular separation. The measurements in the three-jet and Z + two-jet events are based on data collected at a center-of-mass energy of 8 TeV, corresponding to an integrated luminosity of 19.8 fb^{-1}. The Z + two-jet events are reconstructed in the dimuon decay channel of the Z boson. The three-jet measurement is extended to include = 13 TeV data corresponding to an integrated luminosity of 2.3 fb^{-1}. The results are compared to predictions from event generators that include parton showers, multiple parton interactions, and hadronization. The collinear and soft regions are in general well described by parton showers, whereas the regions of large angular separation are often best described by calculations using higher-order matrix elements.
Source
code:CMS_2021_I1847230.cc
// -*- C++ -*-
#include "Rivet/Analysis.hh"
#include "Rivet/Projections/FinalState.hh"
#include "Rivet/Projections/FastJets.hh"
#include "Rivet/Projections/DileptonFinder.hh"
namespace Rivet {
/// @brief Angular distance and momentum ratios in 3-jet and Z+2-jet final states
class CMS_2021_I1847230 : public Analysis {
public:
CMS_2021_I1847230 ()
: Analysis("CMS_2021_I1847230")
{}
void init() {
_mode = 0;
if ( getOption("MODE") == "QCD8TeV" ) _mode = 1;
else if ( getOption("MODE") == "QCD13TeV" ) _mode = 2;
else if ( getOption("MODE") == "ZJet" ) _mode = 3;
if (_mode == 1) {
_jr = 0.5;
book(_h1, "d01-x01-y01");
book(_h2, "d02-x01-y01");
book(_h3, "d03-x01-y01");
book(_h4, "d04-x01-y01");
}
if (_mode == 2) {
_jr = 0.4;
book(_h1, "d05-x01-y01");
book(_h2, "d06-x01-y01");
book(_h3, "d07-x01-y01");
book(_h4, "d08-x01-y01");
}
if (_mode == 1 or _mode == 2) {
const FastJets jets(FinalState(), JetAlg::ANTIKT, _jr);
declare(jets, "jets");
}
if (_mode == 3) {
//PromptFinalState pfs(Cuts::abseta < 2.4 and Cuts::pT > 100*MeV);
DileptonFinder zfinder(91.2*GeV, 0.2, Cuts::abseta < 5 and Cuts::pT > 30*GeV and
Cuts::abspid == PID::MUON, Cuts::massIn(70*GeV, 110*GeV));
declare(zfinder, "DileptonFinder");
declare(FastJets(zfinder.remainingFinalState(), JetAlg::ANTIKT, 0.5), "JetsAK5_zj");
book(_h1, "d09-x01-y01");
book(_h2, "d10-x01-y01");
book(_h3, "d11-x01-y01");
book(_h4, "d12-x01-y01");
book(_ZJw_gen, "TMP/ZJw_gen");
}
}
void analyze(const Event& event) {
if (_mode == 1 or _mode ==2) {
const Jets& jets = apply<JetFinder>(event, "jets").jetsByPt(Cuts::pT > 30.0*GeV);
if (jets.size() < 3) vetoEvent;
const FourMomentum jet1 = jets[0].momentum();
const FourMomentum jet2 = jets[1].momentum();
const FourMomentum jet3 = jets[2].momentum();
if (jet1.pT() < 510.0*GeV) vetoEvent;
if (jet1.absrapidity() > 2.5 or jet2.absrapidity() > 2.5) vetoEvent;
const double del_phi12 = mapAngle0ToPi(jet2.phi() - jet1.phi());
if (abs(del_phi12 - M_PI) > 1.0) vetoEvent;
const double jet3_pt_jet2_pt = jet3.pT()/jet2.pT();
if (!inRange(jet3_pt_jet2_pt, 0.1, 0.9)) vetoEvent;
const double del_r23 = deltaR(jet3.rapidity(), jet3.phi(), jet2.rapidity(), jet2.phi());
if (!inRange(del_r23, _jr+0.1, 1.5)) vetoEvent;
if (del_r23 < 1.0) _h1->fill(jet3_pt_jet2_pt);
if (del_r23 > 1.0) _h2->fill(jet3_pt_jet2_pt);
if (jet3_pt_jet2_pt < 0.3) _h3->fill(del_r23);
if (jet3_pt_jet2_pt > 0.6) _h4->fill(del_r23);
}
if (_mode == 3) {
const DileptonFinder& zfinder = apply<DileptonFinder>(event, "DileptonFinder");
if (zfinder.bosons().size() != 1) vetoEvent;
const Particle& z = zfinder.bosons()[0];
const Particles leptons = sortBy(zfinder.constituents(), cmpMomByPt);
if (leptons[0].pT() < 25.0*GeV or leptons[1].pT() < 10.0*GeV or z.pT() < 80.0*GeV) vetoEvent;
if (leptons[0].absrapidity() > 2.1 or leptons[1].absrapidity() > 2.4) vetoEvent;
const PseudoJets& psjetsAK5_zj = apply<FastJets>(event, "JetsAK5_zj").pseudojetsByPt(20.0*GeV);
if (psjetsAK5_zj.empty()) vetoEvent;
const PseudoJet& j0 = psjetsAK5_zj[0];
const FourMomentum jmom0(j0.e(), j0.px(), j0.py(), j0.pz());
if (jmom0.absrapidity() > 1.0 or jmom0.pT() < 80.0*GeV) vetoEvent;
if (!(deltaPhi(z, jmom0) > 2.0 and deltaR(leptons[0], jmom0) > 0.5 and deltaR(leptons[1], jmom0) > 0.5)) vetoEvent;
_ZJw_gen ->fill();
if(psjetsAK5_zj.size() < 2) vetoEvent;
const PseudoJet& j1 = psjetsAK5_zj[1];
const FourMomentum jmom1(j1.e(), j1.px(), j1.py(), j1.pz());
if(deltaR(leptons[0], jmom1) < 0.5 or deltaR(leptons[1], jmom1) < 0.5 or jmom1.absrapidity() > 2.4) vetoEvent;
const double dR_gen_Jj = deltaR(jmom0, jmom1);
if (!inRange(dR_gen_Jj, 0.5, 1.5)) vetoEvent;
const double rPt_gen_Jj = jmom1.pT()/jmom0.pT();
if (dR_gen_Jj < 1.0) _h1->fill(rPt_gen_Jj);
if (dR_gen_Jj > 1.0) _h2->fill(rPt_gen_Jj);
if (rPt_gen_Jj < 0.3) _h3->fill(dR_gen_Jj);
if (rPt_gen_Jj > 0.6) _h4->fill(dR_gen_Jj);
}
}
void finalize() {
if (_mode == 1 or _mode == 2) {
normalize(_h1);
normalize(_h2);
normalize(_h3);
normalize(_h4);
//scale(_h1, 1.0/_h1->effNumEntries());
//scale(_h2, 1.0/_h2->effNumEntries());
//scale(_h3, 1.0/_h3->effNumEntries());
//scale(_h4, 1.0/_h4->effNumEntries());
}
if (_mode == 3) {
for (size_t i = 0; i < _h1->numBins(); i++) {
_h1->bin(i).scaleW(_h1->bin(i).xWidth());
}
for (size_t i = 0; i < _h2->numBins(); i++) {
_h2->bin(i).scaleW(_h2->bin(i).xWidth());
}
for (size_t i = 0; i < _h3->numBins(); i++) {
_h3->bin(i).scaleW(_h3->bin(i).xWidth());
}
for (size_t i = 0; i < _h4->numBins(); i++) {
_h4->bin(i).scaleW(_h4->bin(i).xWidth());
}
scale(_h1, 1.0/ *_ZJw_gen);
scale(_h2, 1.0/ *_ZJw_gen);
scale(_h3, 1.0/ *_ZJw_gen);
scale(_h4, 1.0/ *_ZJw_gen);
}
}
private:
Histo1DPtr _h1;
Histo1DPtr _h2;
Histo1DPtr _h3;
Histo1DPtr _h4;
CounterPtr _ZJw_gen;
double _jr;
size_t _mode;
};
RIVET_DECLARE_PLUGIN(CMS_2021_I1847230);
}