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| #include "Rivet/Analysis.hh"
#include "Rivet/Projections/FinalState.hh"
#include "Rivet/Projections/FastJets.hh"
#include "Rivet/Projections/ZFinder.hh"
#include "Rivet/Projections/Thrust.hh"
namespace Rivet {
/// CMS Z+jets delta(phi) and jet thrust measurement at 7 TeV
class CMS_2013_I1209721 : public Analysis {
public:
CMS_2013_I1209721()
: Analysis("CMS_2013_I1209721")
{ }
/// Book projections and histograms
void init() {
// Full final state
const FinalState fs((Cuts::etaIn(-5.0,5.0)));
declare(fs, "FS");
// Z finders for electrons and muons
Cut cuts = Cuts::abseta < 2.4 && Cuts::pT > 20*GeV;
const ZFinder zfe(fs, cuts, PID::ELECTRON, 71*GeV, 111*GeV);
const ZFinder zfm(fs, cuts, PID::MUON, 71*GeV, 111*GeV);
declare(zfe, "ZFE");
declare(zfm, "ZFM");
// Jets
const FastJets jets(fs, FastJets::ANTIKT, 0.5);
declare(jets, "JETS");
// Book histograms from data
for (size_t i = 0; i < 2; ++i) {
book(_histDeltaPhiZJ1_1[i] ,1+i*9, 1, 1);
book(_histDeltaPhiZJ1_2[i] ,2+i*9, 1, 1);
book(_histDeltaPhiZJ1_3[i] ,4+i*9, 1, 1);
book(_histDeltaPhiZJ2_3[i] ,5+i*9, 1, 1);
book(_histDeltaPhiZJ3_3[i] ,3+i*9, 1, 1);
book(_histDeltaPhiJ1J2_3[i] ,6+i*9, 1, 1);
book(_histDeltaPhiJ1J3_3[i] ,7+i*9, 1, 1);
book(_histDeltaPhiJ2J3_3[i] ,8+i*9, 1, 1);
book(_histTransvThrust[i] ,9+i*9, 1, 1);
}
}
void analyze(const Event& event) {
const double weight = 1.0;
// Apply the Z finders
const ZFinder& zfe = apply<ZFinder>(event, "ZFE");
const ZFinder& zfm = apply<ZFinder>(event, "ZFM");
// Choose the Z candidate (there must be one)
if (zfe.empty() && zfm.empty()) vetoEvent;
const Particles& z = !zfm.empty() ? zfm.bosons() : zfe.bosons();
const Particles& leptons = !zfm.empty() ? zfm.constituents() : zfe.constituents();
// Determine whether we are in the boosted regime
const bool is_boosted = (z[0].pT() > 150*GeV);
// Build the jets
const FastJets& jetfs = apply<FastJets>(event, "JETS");
const Jets& jets = jetfs.jetsByPt(Cuts::pT > 50*GeV && Cuts::abseta < 2.5);
// Clean the jets against the lepton candidates, as in the paper, with a deltaR cut of 0.4 against the clustered leptons
vector<const Jet*> cleanedJets;
for (size_t i = 0; i < jets.size(); ++i) {
bool isolated = true;
for (size_t j = 0; j < 2; ++j) {
if (deltaR(leptons[j], jets[i]) < 0.4) {
isolated = false;
break;
}
}
if (isolated) cleanedJets.push_back(&jets[i]);
}
// Require at least 1 jet
const unsigned int Njets = cleanedJets.size();
if (Njets < 1) vetoEvent;
// Now compute the thrust
// Collect Z and jets transverse momenta to calculate transverse thrust
vector<Vector3> momenta;
momenta.clear();
Vector3 mom = z[0].p3();
mom.setZ(0);
momenta.push_back(mom);
for (size_t i = 0; i < cleanedJets.size(); ++i) {
Vector3 mj = cleanedJets[i]->momentum().p3();
mj.setZ(0);
momenta.push_back(mj);
}
if (momenta.size() <= 2){
// We need to use a ghost so that Thrust.calc() doesn't return 1.
momenta.push_back(Vector3(0.0000001,0.0000001,0.));
}
Thrust thrust; thrust.calc(momenta);
const double T = thrust.thrust();
FILLx2(_histTransvThrust, is_boosted, log(max(1-T, 1e-6)), weight);
const double dphiZJ1 = deltaPhi(z[0], *cleanedJets[0]);
FILLx2(_histDeltaPhiZJ1_1, is_boosted, dphiZJ1, weight);
if (Njets > 1) {
FILLx2(_histDeltaPhiZJ1_2, is_boosted, dphiZJ1, weight);
if (Njets > 2) {
FILLx2(_histDeltaPhiZJ1_3, is_boosted, dphiZJ1, weight);
FILLx2(_histDeltaPhiZJ2_3, is_boosted, deltaPhi(z[0], *cleanedJets[1]), weight);
FILLx2(_histDeltaPhiZJ3_3, is_boosted, deltaPhi(z[0], *cleanedJets[2]), weight);
FILLx2(_histDeltaPhiJ1J2_3, is_boosted, deltaPhi(*cleanedJets[0], *cleanedJets[1]), weight);
FILLx2(_histDeltaPhiJ1J3_3, is_boosted, deltaPhi(*cleanedJets[0], *cleanedJets[2]), weight);
FILLx2(_histDeltaPhiJ2J3_3, is_boosted, deltaPhi(*cleanedJets[1], *cleanedJets[2]), weight);
}
}
}
/// Normalizations
/// @note Most of these data normalizations neglect the overflow bins
void finalize() {
for (size_t i = 0; i < 2; ++i) {
normalize(_histDeltaPhiZJ1_1[i], 1, false);
normalize(_histDeltaPhiZJ1_2[i], 1, false);
normalize(_histDeltaPhiZJ1_3[i], 1, false);
normalize(_histDeltaPhiZJ2_3[i], 1, false);
normalize(_histDeltaPhiZJ3_3[i], 1, false);
normalize(_histDeltaPhiJ1J2_3[i], 1, false);
normalize(_histDeltaPhiJ1J3_3[i], 1, false);
normalize(_histDeltaPhiJ2J3_3[i], 1, false);
normalize(_histTransvThrust[i]);
}
}
private:
// Define a helper to appropriately fill both unboosted and boosted histo versions
void FILLx2(Histo1DPtr* HNAME, bool is_boosted, double VAL, double weight) {
double x = VAL;
for (size_t i = 0; i < 2; ++i) {
if (i == 0 || is_boosted)
HNAME[i]->fill(x, weight);
}
}
// Arrays of unboosted/boosted histos
Histo1DPtr _histDeltaPhiZJ1_1[2];
Histo1DPtr _histDeltaPhiZJ1_2[2];
Histo1DPtr _histDeltaPhiZJ1_3[2];
Histo1DPtr _histDeltaPhiZJ2_3[2];
Histo1DPtr _histDeltaPhiZJ3_3[2];
Histo1DPtr _histDeltaPhiJ1J2_3[2];
Histo1DPtr _histDeltaPhiJ1J3_3[2];
Histo1DPtr _histDeltaPhiJ2J3_3[2];
Histo1DPtr _histTransvThrust[2];
};
RIVET_DECLARE_PLUGIN(CMS_2013_I1209721);
}
|