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| // -*- C++ -*-
#include "Rivet/Analysis.hh"
#include "Rivet/Projections/FinalState.hh"
#include "Rivet/Projections/ZFinder.hh"
#include "Rivet/Projections/WFinder.hh"
#include "Rivet/Projections/UnstableParticles.hh"
#include "Rivet/Projections/FastJets.hh"
#include "Rivet/Math/LorentzTrans.hh"
namespace Rivet {
class MC_VH2BB : public Analysis {
public:
/// @name Constructors etc.
//@{
/// Constructor
MC_VH2BB()
: Analysis("MC_VH2BB")
{ }
//@}
/// @name Analysis methods
//@{
/// Book histograms and initialise projections before the run
void init() {
FinalState fs;
Cut cut = Cuts::abseta < 3.5 && Cuts::pT > 25*GeV;
ZFinder zeefinder(fs, cut, PID::ELECTRON, 65*GeV, 115*GeV, 0.2);
declare(zeefinder, "ZeeFinder");
ZFinder zmmfinder(fs, cut, PID::MUON, 65*GeV, 115*GeV, 0.2);
declare(zmmfinder, "ZmmFinder");
WFinder wefinder(fs, cut, PID::ELECTRON, 60*GeV, 100*GeV, 25*GeV, 0.2);
declare(wefinder, "WeFinder");
WFinder wmfinder(fs, cut, PID::MUON, 60*GeV, 100*GeV, 25*GeV, 0.2);
declare(wmfinder, "WmFinder");
declare(fs, "FinalState");
declare(FastJets(fs, FastJets::ANTIKT, 0.4), "AntiKT04");
declare(FastJets(fs, FastJets::ANTIKT, 0.5), "AntiKT05");
declare(FastJets(fs, FastJets::ANTIKT, 0.6), "AntiKT06");
/// Book histograms
book(_h_jet_bb_Delta_eta ,"jet_bb_Delta_eta", 50, 0, 4);
book(_h_jet_bb_Delta_phi ,"jet_bb_Delta_phi", 50, 0, 1);
book(_h_jet_bb_Delta_pT ,"jet_bb_Delta_pT", 50,0, 500);
book(_h_jet_bb_Delta_R ,"jet_bb_Delta_R", 50, 0, 5);
book(_h_jet_b_jet_eta ,"jet_b_jet_eta", 50, -4, 4);
book(_h_jet_b_jet_multiplicity ,"jet_b_jet_multiplicity", 11, -0.5, 10.5);
book(_h_jet_b_jet_phi ,"jet_b_jet_phi", 50, 0, 1);
book(_h_jet_b_jet_pT ,"jet_b_jet_pT", 50, 0, 500);
book(_h_jet_H_eta_using_bb ,"jet_H_eta_using_bb", 50, -4, 4);
book(_h_jet_H_mass_using_bb ,"jet_H_mass_using_bb", 50, 50, 200);
book(_h_jet_H_phi_using_bb ,"jet_H_phi_using_bb", 50, 0, 1);
book(_h_jet_H_pT_using_bb ,"jet_H_pT_using_bb", 50, 0, 500);
book(_h_jet_eta ,"jet_eta", 50, -4, 4);
book(_h_jet_multiplicity ,"jet_multiplicity", 11, -0.5, 10.5);
book(_h_jet_phi ,"jet_phi", 50, 0, 1);
book(_h_jet_pT ,"jet_pT", 50, 0, 500);
book(_h_jet_VBbb_Delta_eta ,"jet_VBbb_Delta_eta", 50, 0, 4);
book(_h_jet_VBbb_Delta_phi ,"jet_VBbb_Delta_phi", 50, 0, 1);
book(_h_jet_VBbb_Delta_pT ,"jet_VBbb_Delta_pT", 50, 0, 500);
book(_h_jet_VBbb_Delta_R ,"jet_VBbb_Delta_R", 50, 0, 8);
book(_h_VB_eta ,"VB_eta", 50, -4, 4);
book(_h_VB_mass ,"VB_mass", 50, 60, 110);
book(_h_Z_multiplicity ,"Z_multiplicity", 11, -0.5, 10.5);
book(_h_W_multiplicity ,"W_multiplicity", 11, -0.5, 10.5);
book(_h_VB_phi ,"VB_phi", 50, 0, 1);
book(_h_VB_pT ,"VB_pT", 50, 0, 500);
book(_h_jet_bVB_angle_Hframe ,"jet_bVB_angle_Hframe", 50, 0, 1);
book(_h_jet_bb_angle_Hframe ,"jet_bb_angle_Hframe", 50, 0, 1);
book(_h_jet_bVB_cosangle_Hframe ,"jet_bVB_cosangle_Hframe", 50, -1, 1);
book(_h_jet_bb_cosangle_Hframe ,"jet_bb_cosangle_Hframe", 50, -1, 1);
}
/// Perform the per-event analysis
void analyze(const Event& event) {
const double JETPTCUT = 30*GeV;
const ZFinder& zeefinder = apply<ZFinder>(event, "ZeeFinder");
const ZFinder& zmmfinder = apply<ZFinder>(event, "ZmmFinder");
const WFinder& wefinder = apply<WFinder>(event, "WeFinder");
const WFinder& wmfinder = apply<WFinder>(event, "WmFinder");
const Particles vectorBosons = zeefinder.bosons() + zmmfinder.bosons() + wefinder.bosons() + wmfinder.bosons();
_h_Z_multiplicity->fill(zeefinder.bosons().size() + zmmfinder.bosons().size());
_h_W_multiplicity->fill(wefinder.bosons().size() + wmfinder.bosons().size());
const Jets jets = apply<FastJets>(event, "AntiKT04").jetsByPt(JETPTCUT);
_h_jet_multiplicity->fill(jets.size());
// Identify the b-jets
Jets bjets;
for (const Jet& jet : jets) {
const double jetEta = jet.eta();
const double jetPhi = jet.phi();
const double jetPt = jet.pT();
_h_jet_eta->fill(jetEta);
_h_jet_phi->fill(jetPhi/2/M_PI);
_h_jet_pT->fill(jetPt/GeV);
if (jet.bTagged() && jet.pT() > JETPTCUT) {
bjets.push_back(jet);
_h_jet_b_jet_eta->fill(jetEta);
_h_jet_b_jet_phi->fill(jetPhi/2/M_PI);
_h_jet_b_jet_pT->fill(jetPt);
}
}
_h_jet_b_jet_multiplicity->fill(bjets.size());
// Plot vector boson properties
for (const Particle& v : vectorBosons) {
_h_VB_phi->fill(v.phi()/2/M_PI);
_h_VB_pT->fill(v.pT());
_h_VB_eta->fill(v.eta());
_h_VB_mass->fill(v.mass());
}
// rest of analysis requires at least 1 b jets
if(bjets.empty()) vetoEvent;
// Construct Higgs candidates from pairs of b-jets
for (size_t i = 0; i < bjets.size()-1; ++i) {
for (size_t j = i+1; j < bjets.size(); ++j) {
const Jet& jet1 = bjets[i];
const Jet& jet2 = bjets[j];
const double deltaEtaJJ = fabs(jet1.eta() - jet2.eta());
const double deltaPhiJJ = deltaPhi(jet1.momentum(), jet2.momentum());
const double deltaRJJ = deltaR(jet1.momentum(), jet2.momentum());
const double deltaPtJJ = fabs(jet1.pT() - jet2.pT());
_h_jet_bb_Delta_eta->fill(deltaEtaJJ);
_h_jet_bb_Delta_phi->fill(deltaPhiJJ/M_PI);
_h_jet_bb_Delta_pT->fill(deltaPtJJ);
_h_jet_bb_Delta_R->fill(deltaRJJ);
const FourMomentum phiggs = jet1.momentum() + jet2.momentum();
_h_jet_H_eta_using_bb->fill(phiggs.eta());
_h_jet_H_mass_using_bb->fill(phiggs.mass());
_h_jet_H_phi_using_bb->fill(phiggs.phi()/2/M_PI);
_h_jet_H_pT_using_bb->fill(phiggs.pT());
for (const Particle& v : vectorBosons) {
const double deltaEtaVH = fabs(phiggs.eta() - v.eta());
const double deltaPhiVH = deltaPhi(phiggs, v.momentum());
const double deltaRVH = deltaR(phiggs, v.momentum());
const double deltaPtVH = fabs(phiggs.pT() - v.pT());
_h_jet_VBbb_Delta_eta->fill(deltaEtaVH);
_h_jet_VBbb_Delta_phi->fill(deltaPhiVH/M_PI);
_h_jet_VBbb_Delta_pT->fill(deltaPtVH);
_h_jet_VBbb_Delta_R->fill(deltaRVH);
// Calculate boost angles
const vector<double> angles = boostAngles(jet1.momentum(), jet2.momentum(), v.momentum());
_h_jet_bVB_angle_Hframe->fill(angles[0]/M_PI);
_h_jet_bb_angle_Hframe->fill(angles[1]/M_PI);
_h_jet_bVB_cosangle_Hframe->fill(cos(angles[0]));
_h_jet_bb_cosangle_Hframe->fill(cos(angles[1]));
}
}
}
}
/// Normalise histograms etc., after the run
void finalize() {
scale(_h_jet_bb_Delta_eta, crossSection()/sumOfWeights());
scale(_h_jet_bb_Delta_phi, crossSection()/sumOfWeights());
scale(_h_jet_bb_Delta_pT, crossSection()/sumOfWeights());
scale(_h_jet_bb_Delta_R, crossSection()/sumOfWeights());
scale(_h_jet_b_jet_eta, crossSection()/sumOfWeights());
scale(_h_jet_b_jet_multiplicity, crossSection()/sumOfWeights());
scale(_h_jet_b_jet_phi, crossSection()/sumOfWeights());
scale(_h_jet_b_jet_pT, crossSection()/sumOfWeights());
scale(_h_jet_H_eta_using_bb, crossSection()/sumOfWeights());
scale(_h_jet_H_mass_using_bb, crossSection()/sumOfWeights());
scale(_h_jet_H_phi_using_bb, crossSection()/sumOfWeights());
scale(_h_jet_H_pT_using_bb, crossSection()/sumOfWeights());
scale(_h_jet_eta, crossSection()/sumOfWeights());
scale(_h_jet_multiplicity, crossSection()/sumOfWeights());
scale(_h_jet_phi, crossSection()/sumOfWeights());
scale(_h_jet_pT, crossSection()/sumOfWeights());
scale(_h_jet_VBbb_Delta_eta, crossSection()/sumOfWeights());
scale(_h_jet_VBbb_Delta_phi, crossSection()/sumOfWeights());
scale(_h_jet_VBbb_Delta_pT, crossSection()/sumOfWeights());
scale(_h_jet_VBbb_Delta_R, crossSection()/sumOfWeights());
scale(_h_VB_eta, crossSection()/sumOfWeights());
scale(_h_VB_mass, crossSection()/sumOfWeights());
scale(_h_Z_multiplicity, crossSection()/sumOfWeights());
scale(_h_W_multiplicity, crossSection()/sumOfWeights());
scale(_h_VB_phi, crossSection()/sumOfWeights());
scale(_h_VB_pT, crossSection()/sumOfWeights());
scale(_h_jet_bVB_angle_Hframe, crossSection()/sumOfWeights());
scale(_h_jet_bb_angle_Hframe, crossSection()/sumOfWeights());
scale(_h_jet_bVB_cosangle_Hframe, crossSection()/sumOfWeights());
scale(_h_jet_bb_cosangle_Hframe, crossSection()/sumOfWeights());
}
/// This should take in the four-momenta of two b's (jets/hadrons) and a vector boson, for the process VB*->VBH with H->bb
/// It should return the smallest angle between the virtual vector boson and one of the b's, in the rest frame of the Higgs boson.
/// It should also return (as the second element of the vector) the angle between the b's, in the rest frame of the Higgs boson.
vector<double> boostAngles(const FourMomentum& b1, const FourMomentum& b2, const FourMomentum& vb) {
const FourMomentum higgsMomentum = b1 + b2;
const FourMomentum virtualVBMomentum = higgsMomentum + vb;
const LorentzTransform lt = LorentzTransform::mkFrameTransformFromBeta(higgsMomentum.betaVec());
const FourMomentum virtualVBMomentumBOOSTED = lt.transform(virtualVBMomentum);
const FourMomentum b1BOOSTED = lt.transform(b1);
const FourMomentum b2BOOSTED = lt.transform(b2);
const double angle1 = b1BOOSTED.angle(virtualVBMomentumBOOSTED);
const double angle2 = b2BOOSTED.angle(virtualVBMomentumBOOSTED);
const double anglebb = mapAngle0ToPi(b1BOOSTED.angle(b2BOOSTED));
vector<double> rtn;
rtn.push_back(angle1 < angle2 ? angle1 : angle2);
rtn.push_back(anglebb);
return rtn;
}
//@}
private:
/// @name Histograms
//@{
Histo1DPtr _h_Z_multiplicity, _h_W_multiplicity;
Histo1DPtr _h_jet_bb_Delta_eta, _h_jet_bb_Delta_phi, _h_jet_bb_Delta_pT, _h_jet_bb_Delta_R;
Histo1DPtr _h_jet_b_jet_eta, _h_jet_b_jet_multiplicity, _h_jet_b_jet_phi, _h_jet_b_jet_pT;
Histo1DPtr _h_jet_H_eta_using_bb, _h_jet_H_mass_using_bb, _h_jet_H_phi_using_bb, _h_jet_H_pT_using_bb;
Histo1DPtr _h_jet_eta, _h_jet_multiplicity, _h_jet_phi, _h_jet_pT;
Histo1DPtr _h_jet_VBbb_Delta_eta, _h_jet_VBbb_Delta_phi, _h_jet_VBbb_Delta_pT, _h_jet_VBbb_Delta_R;
Histo1DPtr _h_VB_eta, _h_VB_mass, _h_VB_phi, _h_VB_pT;
Histo1DPtr _h_jet_bVB_angle_Hframe, _h_jet_bb_angle_Hframe, _h_jet_bVB_cosangle_Hframe, _h_jet_bb_cosangle_Hframe;
//Histo1DPtr _h_jet_cuts_bb_deltaR_v_HpT;
//@}
};
// This global object acts as a hook for the plugin system
RIVET_DECLARE_PLUGIN(MC_VH2BB);
}
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