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| // -*- C++ -*-
#include "Rivet/Analysis.hh"
#include "Rivet/Projections/ZFinder.hh"
#include "Rivet/Projections/FastJets.hh"
#include "Rivet/Projections/FinalState.hh"
#include "Rivet/Projections/VetoedFinalState.hh"
#include "Rivet/Projections/IdentifiedFinalState.hh"
#include "Rivet/Projections/LeadingParticlesFinalState.hh"
namespace Rivet {
/// ATLAS Z+jets in pp at 7 TeV
class ATLAS_2011_I945498 : public Analysis {
public:
/// Constructor
ATLAS_2011_I945498()
: Analysis("ATLAS_2011_I945498")
{ }
/// Book histograms and initialise projections before the run
void init() {
// Variable initialisation
_isZeeSample = false;
_isZmmSample = false;
for (size_t chn = 0; chn < 3; ++chn) {
book(weights_nj0[chn], "weights_nj0_" + to_str(chn));
book(weights_nj1[chn], "weights_nj1_" + to_str(chn));
book(weights_nj2[chn], "weights_nj2_" + to_str(chn));
book(weights_nj3[chn], "weights_nj3_" + to_str(chn));
book(weights_nj4[chn], "weights_nj4_" + to_str(chn));
}
// Set up projections
FinalState fs;
ZFinder zfinder_mu(fs, Cuts::abseta < 2.4 && Cuts::pT > 20*GeV, PID::MUON, 66*GeV, 116*GeV, 0.1, ZFinder::ClusterPhotons::NODECAY);
declare(zfinder_mu, "ZFinder_mu");
Cut cuts = (Cuts::abseta < 1.37 || Cuts::absetaIn(1.52, 2.47)) && Cuts::pT > 20*GeV;
ZFinder zfinder_el(fs, cuts, PID::ELECTRON, 66*GeV, 116*GeV, 0.1, ZFinder::ClusterPhotons::NODECAY);
declare(zfinder_el, "ZFinder_el");
Cut cuts25_20 = Cuts::abseta < 2.5 && Cuts::pT > 20*GeV;
// For combined cross-sections (combined phase space + dressed level)
ZFinder zfinder_comb_mu(fs, cuts25_20, PID::MUON, 66.0*GeV, 116.0*GeV, 0.1, ZFinder::ClusterPhotons::NODECAY);
declare(zfinder_comb_mu, "ZFinder_comb_mu");
ZFinder zfinder_comb_el(fs, cuts25_20, PID::ELECTRON, 66.0*GeV, 116.0*GeV, 0.1, ZFinder::ClusterPhotons::NODECAY);
declare(zfinder_comb_el, "ZFinder_comb_el");
// Define veto FS in order to prevent Z-decay products entering the jet algorithm
VetoedFinalState remfs;
remfs.addVetoOnThisFinalState(zfinder_el);
remfs.addVetoOnThisFinalState(zfinder_mu);
VetoedFinalState remfs_comb;
remfs_comb.addVetoOnThisFinalState(zfinder_comb_el);
remfs_comb.addVetoOnThisFinalState(zfinder_comb_mu);
FastJets jets(remfs, FastJets::ANTIKT, 0.4);
jets.useInvisibles();
declare(jets, "jets");
FastJets jets_comb(remfs_comb, FastJets::ANTIKT, 0.4);
jets_comb.useInvisibles();
declare(jets_comb, "jets_comb");
// 0=el, 1=mu, 2=comb
for (size_t chn = 0; chn < 3; ++chn) {
book(_h_njet_incl[chn] ,1, 1, chn+1);
book(_h_njet_ratio[chn] ,2, 1, chn+1);
book(_h_ptjet[chn] ,3, 1, chn+1);
book(_h_ptlead[chn] ,4, 1, chn+1);
book(_h_ptseclead[chn] ,5, 1, chn+1);
book(_h_yjet[chn] ,6, 1, chn+1);
book(_h_ylead[chn] ,7, 1, chn+1);
book(_h_yseclead[chn] ,8, 1, chn+1);
book(_h_mass[chn] ,9, 1, chn+1);
book(_h_deltay[chn] ,10, 1, chn+1);
book(_h_deltaphi[chn] ,11, 1, chn+1);
book(_h_deltaR[chn] ,12, 1, chn+1);
}
}
// Jet selection criteria universal for electron and muon channel
/// @todo Replace with a Cut passed to jetsByPt
Jets selectJets(const ZFinder* zf, const FastJets* allJets) {
const FourMomentum l1 = zf->constituents()[0].momentum();
const FourMomentum l2 = zf->constituents()[1].momentum();
Jets jets;
for (const Jet& jet : allJets->jetsByPt(30*GeV)) {
const FourMomentum jmom = jet.momentum();
if (jmom.absrap() < 4.4 &&
deltaR(l1, jmom) > 0.5 && deltaR(l2, jmom) > 0.5) {
jets.push_back(jet);
}
}
return jets;
}
/// Perform the per-event analysis
void analyze(const Event& event) {
vector<const ZFinder*> zfs;
zfs.push_back(& (apply<ZFinder>(event, "ZFinder_el")));
zfs.push_back(& (apply<ZFinder>(event, "ZFinder_mu")));
zfs.push_back(& (apply<ZFinder>(event, "ZFinder_comb_el")));
zfs.push_back(& (apply<ZFinder>(event, "ZFinder_comb_mu")));
vector<const FastJets*> fjs;
fjs.push_back(& (apply<FastJets>(event, "jets")));
fjs.push_back(& (apply<FastJets>(event, "jets_comb")));
// Determine what kind of MC sample this is
const bool isZee = (zfs[0]->bosons().size() == 1) || (zfs[2]->bosons().size() == 1);
const bool isZmm = (zfs[1]->bosons().size() == 1) || (zfs[3]->bosons().size() == 1);
if (isZee) _isZeeSample = true;
if (isZmm) _isZmmSample = true;
// Require exactly one electronic or muonic Z-decay in the event
bool isZeemm = ( (zfs[0]->bosons().size() == 1 && zfs[1]->bosons().size() != 1) ||
(zfs[1]->bosons().size() == 1 && zfs[0]->bosons().size() != 1) );
bool isZcomb = ( (zfs[2]->bosons().size() == 1 && zfs[3]->bosons().size() != 1) ||
(zfs[3]->bosons().size() == 1 && zfs[2]->bosons().size() != 1) );
if (!isZeemm && !isZcomb) vetoEvent;
vector<int> zfIDs;
vector<int> fjIDs;
if (isZeemm) {
int chn = zfs[0]->bosons().size() == 1 ? 0 : 1;
zfIDs.push_back(chn);
fjIDs.push_back(0);
}
if (isZcomb) {
int chn = zfs[2]->bosons().size() == 1 ? 2 : 3;
zfIDs.push_back(chn);
fjIDs.push_back(1);
}
for (size_t izf = 0; izf < zfIDs.size(); ++izf) {
int zfID = zfIDs[izf];
int fjID = fjIDs[izf];
int chn = zfID;
if (zfID == 2 || zfID == 3) chn = 2;
Jets jets = selectJets(zfs[zfID], fjs[fjID]);
switch (jets.size()) {
case 0:
weights_nj0[chn]->fill();
break;
case 1:
weights_nj0[chn]->fill();
weights_nj1[chn]->fill();
break;
case 2:
weights_nj0[chn]->fill();
weights_nj1[chn]->fill();
weights_nj2[chn]->fill();
break;
case 3:
weights_nj0[chn]->fill();
weights_nj1[chn]->fill();
weights_nj2[chn]->fill();
weights_nj3[chn]->fill();
break;
default: // >= 4
weights_nj0[chn]->fill();
weights_nj1[chn]->fill();
weights_nj2[chn]->fill();
weights_nj3[chn]->fill();
weights_nj4[chn]->fill();
}
// Require at least one jet
if (jets.empty()) continue;
// Fill jet multiplicities
for (size_t ijet = 1; ijet <= jets.size(); ++ijet) {
_h_njet_incl[chn]->fill(ijet);
}
// Loop over selected jets, fill inclusive jet distributions
for (size_t ijet = 0; ijet < jets.size(); ++ijet) {
_h_ptjet[chn]->fill(jets[ijet].pT()/GeV);
_h_yjet [chn]->fill(fabs(jets[ijet].rapidity()));
}
// Leading jet histos
const double ptlead = jets[0].pT()/GeV;
const double yabslead = fabs(jets[0].rapidity());
_h_ptlead[chn]->fill(ptlead);
_h_ylead [chn]->fill(yabslead);
if (jets.size() >= 2) {
// Second jet histos
const double pt2ndlead = jets[1].pT()/GeV;
const double yabs2ndlead = fabs(jets[1].rapidity());
_h_ptseclead[chn] ->fill(pt2ndlead);
_h_yseclead [chn] ->fill(yabs2ndlead);
// Dijet histos
const double deltaphi = fabs(deltaPhi(jets[1], jets[0]));
const double deltarap = fabs(jets[0].rapidity() - jets[1].rapidity()) ;
const double deltar = fabs(deltaR(jets[0], jets[1], RAPIDITY));
const double mass = (jets[0].momentum() + jets[1].momentum()).mass();
_h_mass [chn] ->fill(mass/GeV);
_h_deltay [chn] ->fill(deltarap);
_h_deltaphi[chn] ->fill(deltaphi);
_h_deltaR [chn] ->fill(deltar);
}
}
}
/// @name Ratio calculator util functions
//@{
/// Calculate the ratio, being careful about div-by-zero
double ratio(double a, double b) {
return (b != 0) ? a/b : 0;
}
/// Calculate the ratio error, being careful about div-by-zero
double ratio_err(double a, double b) {
return (b != 0) ? sqrt(a/sqr(b) + sqr(a)/(b*b*b)) : 0;
}
//@}
void finalize() {
// Fill ratio histograms
for (size_t chn = 0; chn < 3; ++chn) {
_h_njet_ratio[chn]->addPoint(1, ratio(weights_nj1[chn]->val(), weights_nj0[chn]->val()), 0.5, ratio_err(weights_nj1[chn]->val(), weights_nj0[chn]->val()));
_h_njet_ratio[chn]->addPoint(2, ratio(weights_nj2[chn]->val(), weights_nj1[chn]->val()), 0.5, ratio_err(weights_nj2[chn]->val(), weights_nj1[chn]->val()));
_h_njet_ratio[chn]->addPoint(3, ratio(weights_nj3[chn]->val(), weights_nj2[chn]->val()), 0.5, ratio_err(weights_nj3[chn]->val(), weights_nj2[chn]->val()));
_h_njet_ratio[chn]->addPoint(4, ratio(weights_nj4[chn]->val(), weights_nj3[chn]->val()), 0.5, ratio_err(weights_nj4[chn]->val(), weights_nj3[chn]->val()));
}
// Scale other histos
for (size_t chn = 0; chn < 3; ++chn) {
// For ee and mumu channels: normalize to Njet inclusive cross-section
double xs = crossSectionPerEvent()/picobarn;
if (chn != 2 && weights_nj0[chn]->val() != 0.) xs = 1.0 / weights_nj0[chn]->val();
// For inclusive MC sample(ee/mmu channels together) we want the single-lepton-flavor xsec
if (_isZeeSample && _isZmmSample) xs *= 0.5;
// Special case histogram: always not normalized
scale(_h_njet_incl[chn], (chn < 2) ? crossSectionPerEvent()/picobarn : xs);
scale(_h_ptjet[chn] , xs);
scale(_h_ptlead[chn] , xs);
scale(_h_ptseclead[chn], xs);
scale(_h_yjet[chn] , xs);
scale(_h_ylead[chn] , xs);
scale(_h_yseclead[chn] , xs);
scale(_h_deltaphi[chn] , xs);
scale(_h_deltay[chn] , xs);
scale(_h_deltaR[chn] , xs);
scale(_h_mass[chn] , xs);
}
}
//@}
private:
bool _isZeeSample;
bool _isZmmSample;
CounterPtr weights_nj0[3];
CounterPtr weights_nj1[3];
CounterPtr weights_nj2[3];
CounterPtr weights_nj3[3];
CounterPtr weights_nj4[3];
Scatter2DPtr _h_njet_ratio[3];
Histo1DPtr _h_njet_incl[3];
Histo1DPtr _h_ptjet[3];
Histo1DPtr _h_ptlead[3];
Histo1DPtr _h_ptseclead[3];
Histo1DPtr _h_yjet[3];
Histo1DPtr _h_ylead[3];
Histo1DPtr _h_yseclead[3];
Histo1DPtr _h_deltaphi[3];
Histo1DPtr _h_deltay[3];
Histo1DPtr _h_deltaR[3];
Histo1DPtr _h_mass[3];
};
RIVET_DECLARE_PLUGIN(ATLAS_2011_I945498);
}
|