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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/VetoedFinalState.hh"
#include "Rivet/Projections/IdentifiedFinalState.hh"
#include "Rivet/Projections/FastJets.hh"
#include "Rivet/Tools/RivetMT2.hh"
namespace Rivet {
/// @author Peter Richardson
class ATLAS_2012_I1190891 : public Analysis {
public:
/// Constructor
ATLAS_2012_I1190891()
: Analysis("ATLAS_2012_I1190891")
{ }
/// @name Analysis methods
//@{
/// Book histograms and initialise projections before the run
void init() {
// projection to find the electrons
IdentifiedFinalState elecs(Cuts::abseta < 2.47 && Cuts::pT > 10*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");
// for pTmiss
declare(VisibleFinalState(Cuts::abseta < 4.9),"vfs");
VetoedFinalState vfs;
vfs.addVetoPairId(PID::MUON);
/// Jet finder
declare(FastJets(vfs, FastJets::ANTIKT, 0.4), "AntiKtJets04");
// all tracks (to do deltaR with leptons)
declare(ChargedFinalState((Cuts::etaIn(-3.0,3.0))),"cfs");
// Book histograms
book(_hist_etmiss ,"hist_etmiss",10,0.,500.);
book(_hist_meff ,"hist_m_eff",7,0.,1050.);
book(_count_SR1 ,"count_SR1", 1, 0., 1.);
book(_count_SR2 ,"count_SR2", 1, 0., 1.);
}
/// Perform the per-event analysis
void analyze(const Event& event) {
const double weight = 1.0;
// get the jet candidates
Jets cand_jets;
for (const Jet& jet :
apply<FastJets>(event, "AntiKtJets04").jetsByPt(20.0*GeV) ) {
if ( fabs( jet.eta() ) < 2.5 ) {
cand_jets.push_back(jet);
}
}
// candidate muons
Particles cand_mu;
Particles chg_tracks =
apply<ChargedFinalState>(event, "cfs").particles();
for ( const Particle & mu :
apply<IdentifiedFinalState>(event, "muons").particlesByPt() ) {
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 )
cand_mu.push_back(mu);
}
// candidate electrons
Particles cand_e;
for ( const Particle & e :
apply<IdentifiedFinalState>(event, "elecs").particlesByPt() ) {
double pTinCone = -e.perp();
for ( const Particle & track : chg_tracks ) {
if ( deltaR(e.momentum(),track.momentum()) <= 0.2 )
pTinCone += track.pT();
}
if (pTinCone/e.perp()<0.1) {
cand_e.push_back(e);
}
}
// resolve jet/lepton ambiguity
Jets recon_jets;
for ( const Jet& jet : cand_jets ) {
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 );
}
// only keep electrons more than R=0.4 from jets
Particles cand2_e;
for(unsigned int ie=0;ie<cand_e.size();++ie) {
const Particle & e = cand_e[ie];
// at least 0.4 from any jets
bool away = true;
for ( const Jet& jet : recon_jets ) {
if ( deltaR(e.momentum(),jet.momentum()) < 0.4 ) {
away = false;
break;
}
}
// and 0.1 from any muons
if ( away ) {
for ( const Particle & mu : cand_mu ) {
if ( deltaR(mu.momentum(),e.momentum()) < 0.1 ) {
away = false;
break;
}
}
}
// and 0.1 from electrons ( keep higher energy)
for(unsigned int ie2=0;ie2<cand_e.size();++ie2) {
if(ie==ie2) continue;
if ( deltaR(e.momentum(),cand_e[ie2].momentum()) < 0.1 &&
e.E() < cand_e[ie2].E() ) {
away = false;
break;
}
}
// if isolated keep it
if ( away )
cand2_e.push_back( e );
}
// remove e+e- pairs with mass < 20.
Particles recon_e;
for(unsigned int ie=0;ie<cand2_e.size();++ie) {
bool pass = true;
for(unsigned int ie2=0;ie2<cand2_e.size();++ie2) {
if(cand2_e[ie].pid()*cand2_e[ie2].pid()>0) continue;
double mtest = (cand2_e[ie].momentum()+cand2_e[ie2].momentum()).mass();
if(mtest<=20.) {
pass = false;
break;
}
}
if(pass) recon_e.push_back(cand2_e[ie]);
}
// only keep muons more than R=0.4 from jets
Particles cand2_mu;
for(unsigned int imu=0;imu<cand_mu.size();++imu) {
const Particle & mu = cand_mu[imu];
bool away = true;
// at least 0.4 from any jets
for ( const Jet& jet : recon_jets ) {
if ( deltaR(mu.momentum(),jet.momentum()) < 0.4 ) {
away = false;
break;
}
}
// and 0.1 from any electrona
if ( away ) {
for ( const Particle & e : cand_e ) {
if ( deltaR(mu.momentum(),e.momentum()) < 0.1 ) {
away = false;
break;
}
}
}
if ( away )
cand2_mu.push_back( mu );
}
// remove mu+mu- pairs with mass < 20.
Particles recon_mu;
for(unsigned int imu=0;imu<cand2_mu.size();++imu) {
bool pass = true;
for(unsigned int imu2=0;imu2<cand2_mu.size();++imu2) {
if(cand2_mu[imu].pid()*cand2_mu[imu2].pid()>0) continue;
double mtest = (cand2_mu[imu].momentum()+cand2_mu[imu2].momentum()).mass();
if(mtest<=20.) {
pass = false;
break;
}
}
if(pass) recon_mu.push_back(cand2_mu[imu]);
}
// pTmiss
Particles vfs_particles =
apply<VisibleFinalState>(event, "vfs").particles();
FourMomentum pTmiss;
for ( const Particle & p : vfs_particles ) {
pTmiss -= p.momentum();
}
double eTmiss = pTmiss.pT();
// now only use recon_jets, recon_mu, recon_e
// reject events with less than 4 electrons and muons
if ( recon_mu.size() + recon_e.size() < 4 ) {
MSG_DEBUG("To few charged leptons left after selection");
vetoEvent;
}
// check if passes single lepton trigger
bool passSingle =
( !recon_e .empty() && recon_e[0] .perp()>25. )||
( !recon_mu.empty() && recon_mu[0].perp()>20.);
// or two lepton trigger
bool passDouble =
( recon_mu.size()>=2 && recon_mu[1].perp()>12.) ||
( recon_e .size()>=2 && recon_e [1].perp()>17.) ||
( !recon_e.empty() && !recon_mu.empty() &&
recon_e[0].perp()>15. && recon_mu[0].perp()>10.);
// must pass a trigger
if( !passSingle && !passDouble ) {
MSG_DEBUG("Hardest lepton fails trigger");
vetoEvent;
}
// calculate meff
double meff = eTmiss;
for ( const Particle & e : recon_e )
meff += e.perp();
for ( const Particle & mu : recon_mu )
meff += mu.perp();
for ( const Jet & jet : recon_jets ) {
double pT = jet.perp();
if(pT>40.) meff += pT;
}
// mass of SFOS pairs closest to the Z mass
for(unsigned int ix=0;ix<recon_e.size();++ix) {
for(unsigned int iy=ix+1;iy<recon_e.size();++iy) {
if(recon_e[ix].pid()*recon_e[iy].pid()>0) continue;
double mtest = (recon_e[ix].momentum()+recon_e[iy].momentum()).mass();
if(mtest>81.2 && mtest<101.2) vetoEvent;
}
}
for(unsigned int ix=0;ix<recon_mu.size();++ix) {
for(unsigned int iy=ix+1;iy<recon_mu.size();++iy) {
if(recon_mu[ix].pid()*recon_mu[iy].pid()>0) continue;
double mtest = (recon_mu[ix].momentum()+recon_mu[iy].momentum()).mass();
if(mtest>81.2 && mtest<101.2) vetoEvent;
}
}
// make the control plots
_hist_etmiss ->fill(eTmiss,weight);
_hist_meff ->fill(meff ,weight);
// finally the counts
if(eTmiss>50.) _count_SR1->fill(0.5,weight);
if(meff >300.) _count_SR2->fill(0.5,weight);
}
//@}
void finalize() {
double norm = crossSection()/femtobarn*4.7/sumOfWeights();
scale(_hist_etmiss,norm* 50.);
scale(_hist_meff ,norm*150.);
scale(_count_SR1,norm);
scale(_count_SR2,norm);
}
private:
/// @name Histograms
//@{
Histo1DPtr _hist_etmiss;
Histo1DPtr _hist_meff;
Histo1DPtr _count_SR1;
Histo1DPtr _count_SR2;
//@}
};
// The hook for the plugin system
RIVET_DECLARE_PLUGIN(ATLAS_2012_I1190891);
}
|