Rivet analyses
Run II jet azimuthal decorrelation analysis
Experiment: D0 (Tevatron Run 2)
Inspire ID: 659398
Status: VALIDATED
Authors: - Lars Sonnenschein
References: - Phys. Rev. Lett., 94, 221801 (2005) - arXiv: hep-ex/0409040
Beams: p- p+
Beam energies: (980.0, 980.0)GeV
Run details: - QCD events in ppbar interactions at $\sqrt{s} = 1960$ GeV.
Correlations in the azimuthal angle between the two largest pT jets have been measured using the D0 detector in ppbar collisions at 1960~GeV. The analysis is based on an inclusive dijet event sample in the central rapidity region. The correlations are determined for four different pT intervals.
Source
code:D0_2004_I659398.cc
// -*- C++ -*-
#include "Rivet/Analysis.hh"
#include "Rivet/Projections/FastJets.hh"
#include "Rivet/Projections/VetoedFinalState.hh"
#include "Rivet/Projections/VisibleFinalState.hh"
#include "Rivet/Projections/MissingMomentum.hh"
namespace Rivet {
/// @brief D0 Run II angular correlations in di-jet events
/// @author Lars Sonnenschein
///
/// Measurement of angular correlations in di-jet events.
///
/// @par Run conditions
/// @arg \f$ \sqrt{s} = \f$ 1960 GeV
/// @arg Run with generic QCD events.
/// @arg Several \f$ p_\perp^\text{min} \f$ cutoffs are probably required to fill the histograms:
/// @arg \f$ p_\perp^\text{min} = \f$ 50, 75, 100, 150 GeV for the four pT ranges respecively
///
class D0_2004_I659398 : public Analysis {
public:
RIVET_DEFAULT_ANALYSIS_CTOR(D0_2004_I659398);
/// @name Analysis methods
/// @{
void init() {
// Final state for jets, mET etc.
const FinalState fs(Cuts::abseta < 3.0);
declare(fs, "FS");
// Veto neutrinos, and muons with pT above 1.0 GeV
VetoedFinalState vfs(fs);
vfs.vetoNeutrinos();
vfs.addVetoPairDetail(PID::MUON, 1.0*GeV, DBL_MAX);
declare(vfs, "VFS");
declare(FastJets(vfs, JetAlg::D0ILCONE, 0.7), "Jets");
declare(MissingMomentum(vfs), "CalMET");
// Book histograms
book(_histJetAzimuth_pTmax75_100 ,1, 2, 1);
book(_histJetAzimuth_pTmax100_130 ,2, 2, 1);
book(_histJetAzimuth_pTmax130_180 ,3, 2, 1);
book(_histJetAzimuth_pTmax180_ ,4, 2, 1);
}
/// Do the analysis
void analyze(const Event& event) {
// Analyse and print some info
const JetFinder& jetpro = apply<JetFinder>(event, "Jets");
MSG_DEBUG("Jet multiplicity before any pT cut = " << jetpro.size());
const Jets jets = jetpro.jetsByPt(Cuts::pT > 40.0*GeV);
if (jets.size() >= 2) {
MSG_DEBUG("Jet multiplicity after pT > 40 GeV cut = " << jets.size());
}
else vetoEvent;
const double rap1 = jets[0].absrap();
const double rap2 = jets[1].absrap();
if (rap1 > 0.5 || rap2 > 0.5) {
vetoEvent;
}
MSG_DEBUG("Jet eta and pT requirements fulfilled");
const double pT1 = jets[0].pT();
const MissingMomentum& caloMissEt = apply<MissingMomentum>(event, "CalMET");
MSG_DEBUG("Missing vector Et = " << caloMissEt.vectorEt()/GeV << " GeV");
if (caloMissEt.vectorEt().mod() > 0.7*pT1) {
MSG_DEBUG("Vetoing event with too much missing ET: "
<< caloMissEt.vectorEt()/GeV << " GeV > "
<< 0.7*pT1/GeV << " GeV");
vetoEvent;
}
if (pT1/GeV >= 75.0) {
const double dphi = deltaPhi(jets[0].phi(), jets[1].phi());
if (inRange(pT1/GeV, 75.0, 100.0)) {
_histJetAzimuth_pTmax75_100->fill(dphi);
} else if (inRange(pT1/GeV, 100.0, 130.0)) {
_histJetAzimuth_pTmax100_130->fill(dphi);
} else if (inRange(pT1/GeV, 130.0, 180.0)) {
_histJetAzimuth_pTmax130_180->fill(dphi);
} else if (pT1/GeV > 180.0) {
_histJetAzimuth_pTmax180_->fill(dphi);
}
}
}
// Finalize
void finalize() {
// Normalize histograms to unit area
normalize(_histJetAzimuth_pTmax75_100);
normalize(_histJetAzimuth_pTmax100_130);
normalize(_histJetAzimuth_pTmax130_180);
normalize(_histJetAzimuth_pTmax180_);
}
/// @}
private:
/// @name Histograms
/// @{
Histo1DPtr _histJetAzimuth_pTmax75_100;
Histo1DPtr _histJetAzimuth_pTmax100_130;
Histo1DPtr _histJetAzimuth_pTmax130_180;
Histo1DPtr _histJetAzimuth_pTmax180_;
/// @}
};
RIVET_DECLARE_ALIASED_PLUGIN(D0_2004_I659398, D0_2004_S5992206);
}Aliases: - D0_2004_S5992206