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| // -*- C++ -*-
#include "Rivet/Analysis.hh"
#include "Rivet/Projections/FinalState.hh"
#include "Rivet/Projections/ChargedFinalState.hh"
#include "Rivet/Projections/VisibleFinalState.hh"
#include "Rivet/Projections/IdentifiedFinalState.hh"
#include "Rivet/Projections/VetoedFinalState.hh"
#include "Rivet/Projections/FastJets.hh"
namespace Rivet {
class ATLAS_2012_I1186556 : public Analysis {
public:
/// Constructor
ATLAS_2012_I1186556()
: Analysis("ATLAS_2012_I1186556")
{ }
/// @name Analysis methods
//@{
/// Book histograms and initialize projections before the run
void init() {
// projection to find the electrons
IdentifiedFinalState elecs(Cuts::abseta < 2.47 && Cuts::pT > 20*GeV);
elecs.acceptIdPair(PID::ELECTRON);
declare(elecs, "elecs");
// projection to find the muons
IdentifiedFinalState muons(Cuts::abseta < 2.4 && Cuts::pT > 10*GeV);
muons.acceptIdPair(PID::MUON);
declare(muons, "muons");
// Jet finder
VetoedFinalState vfs;
vfs.addVetoPairId(PID::MUON);
declare(FastJets(vfs, FastJets::ANTIKT, 0.4), "AntiKtJets04");
// all tracks (to do deltaR with leptons)
declare(ChargedFinalState(Cuts::abseta < 3.0 && Cuts::pT > 1*GeV), "cfs");
// for pTmiss
declare(VisibleFinalState(Cuts::abseta < 4.9),"vfs");
// Book histograms
book(_count_SR_SF ,"count_SR_SF" , 1, 0., 1.);
book(_count_SR_OF ,"count_SR_OF" , 1, 0., 1.);
book(_hist_mT2_SF_exp ,"hist_mT2_SF_exp", 40 , 0., 200. );
book(_hist_mT2_OF_exp ,"hist_mT2_OF_exp", 40 , 0., 200. );
book(_hist_mT2_SF_MC ,"hist_mT2_SF_MC" , 500, 0., 1000.);
book(_hist_mT2_OF_MC ,"hist_mT2_OF_MC" , 500, 0., 1000.);
}
/// Perform the per-event analysis
void analyze(const Event& event) {
const double weight = 1.0;
// get the candiate jets
Jets cand_jets;
for ( const Jet& jet :
apply<FastJets>(event, "AntiKtJets04").jetsByPt(20.0*GeV) ) {
if ( fabs( jet.eta() ) < 4.5 ) {
cand_jets.push_back(jet);
}
}
// charged tracks for isolation
Particles chg_tracks =
apply<ChargedFinalState>(event, "cfs").particles();
// find the electrons
Particles cand_e;
for( const Particle & e :
apply<IdentifiedFinalState>(event, "elecs").particlesByPt()) {
// remove any leptons within 0.4 of any candidate jets
bool e_near_jet = false;
for ( const Jet& jet : cand_jets ) {
double dR = deltaR(e.momentum(),jet.momentum());
if ( dR < 0.4 && dR > 0.2 ) {
e_near_jet = true;
break;
}
}
if ( e_near_jet ) continue;
cand_e.push_back(e);
}
Particles cand_mu;
for( const Particle & mu :
apply<IdentifiedFinalState>(event, "muons").particlesByPt()) {
// remove any leptons within 0.4 of any candidate jets
bool mu_near_jet = false;
for ( const Jet& jet : cand_jets ) {
if ( deltaR(mu.momentum(),jet.momentum()) < 0.4 ) {
mu_near_jet = true;
break;
}
}
if ( mu_near_jet ) continue;
cand_mu.push_back(mu);
}
// pTcone around muon track
Particles recon_mu;
for ( const Particle & mu : cand_mu ) {
double pTinCone = -mu.pT();
for ( const Particle & track : chg_tracks ) {
if ( deltaR(mu.momentum(),track.momentum()) < 0.2 )
pTinCone += track.pT();
}
if ( pTinCone < 1.8*GeV ) recon_mu.push_back(mu);
}
// pTcone around electron track
Particles recon_e;
for ( const Particle & e : cand_e ) {
double pTinCone = -e.pT();
for ( const Particle & track : chg_tracks ) {
if ( deltaR(e.momentum(),track.momentum()) < 0.2 )
pTinCone += track.pT();
}
if ( pTinCone < 0.1 * e.pT() ) recon_e.push_back(e);
}
// pTmiss
FourMomentum pTmiss;
for ( const Particle & p :
apply<VisibleFinalState>(event, "vfs").particles() ) {
pTmiss -= p.momentum();
}
// discard jets that overlap with electrons
Jets recon_jets;
for ( const Jet& jet : cand_jets ) {
if(jet.abseta()>2.5||
jet.perp()<20.) continue;
bool away_from_e = true;
for ( const Particle & e : cand_e ) {
if ( deltaR(e.momentum(),jet.momentum()) < 0.2 ) {
away_from_e = false;
break;
}
}
if ( away_from_e ) recon_jets.push_back( jet );
}
// put leptons into 1 vector and order by pT
Particles leptons(recon_e.begin(),recon_e.end());
leptons.insert(leptons.begin(),recon_mu.begin(),recon_mu.end());
sort(leptons.begin(),leptons.end(),cmpMomByPt);
// exactly two leptons
if(leptons.size() !=2) vetoEvent;
// hardest lepton pT greater the 25 (20) e(mu)
if( (leptons[0].abspid()==PID::ELECTRON && leptons[0].perp()<25.) ||
(leptons[0].abspid()==PID::ELECTRON && leptons[0].perp()<20.))
vetoEvent;
// require opposite sign
if(leptons[0].pid()*leptons[1].pid()>0) vetoEvent;
// and invariant mass > 20
double mll = (leptons[0].momentum() + leptons[1].momentum()).mass();
if(mll<20.) vetoEvent;
// two jets 1st pT > 50 and second pT> 25
if(recon_jets.size()<2 || recon_jets[0].perp()<50. ||
recon_jets[1].perp()<25.) vetoEvent;
// calculate mT2
double m_T2 = mT2( leptons[0], leptons[1], pTmiss,0.0 ); // zero mass invisibles
// same flavour region
if(leptons[0].pid()==-leptons[1].pid()) {
// remove Z region
if(mll>71.&&mll<111.) vetoEvent;
// require at least 1 b jet
unsigned int n_b=0;
for(unsigned int ix=0;ix<recon_jets.size();++ix) {
if(recon_jets[ix].bTagged() && rand()/static_cast<double>(RAND_MAX)<=0.60)
++n_b;
}
if(n_b==0) vetoEvent;
_hist_mT2_SF_exp->fill(m_T2,weight);
_hist_mT2_SF_MC ->fill(m_T2,weight);
if(m_T2>120.) _count_SR_SF->fill(0.5,weight);
}
// opposite flavour region
else {
_hist_mT2_OF_exp->fill(m_T2,weight);
_hist_mT2_OF_MC ->fill(m_T2,weight);
if(m_T2>120.) _count_SR_OF->fill(0.5,weight);
}
}
//@}
void finalize() {
double norm = 4.7* crossSection()/sumOfWeights()/femtobarn;
scale(_count_SR_SF , norm);
scale(_count_SR_OF , norm);
scale(_hist_mT2_SF_exp,5.*norm);
scale(_hist_mT2_OF_exp,5.*norm);
scale(_hist_mT2_SF_MC , norm/4.7);
scale(_hist_mT2_OF_MC , norm/4.7);
}
private:
/// @name Histograms
//@{
Histo1DPtr _count_SR_SF;
Histo1DPtr _count_SR_OF;
Histo1DPtr _hist_mT2_SF_exp;
Histo1DPtr _hist_mT2_OF_exp;
Histo1DPtr _hist_mT2_SF_MC;
Histo1DPtr _hist_mT2_OF_MC;
//@}
};
// The hook for the plugin system
RIVET_DECLARE_PLUGIN(ATLAS_2012_I1186556);
}
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