Jet Class Reference

A minimal class representing a jet of particles. More...

#include <Jet.hh>

Inheritance diagram for Jet:
Inheritance graph
[legend]
Collaboration diagram for Jet:
Collaboration graph
[legend]

List of all members.

Public Types

typedef vector< FourMomentum >
::iterator 		iterator
 Define a Jet::iterator via a typedef.
typedef vector< FourMomentum >
::const_iterator 		const_iterator
 Define a Jet::const_iterator via a typedef.

Public Member Functions

 Jet ()
 Constructor.
iterator begin ()
 Get a begin iterator over the particle/track four-momenta in this jet.
iterator end ()
 Get an end iterator over the particle/track four-momenta in this jet.
const_iterator begin () const
 Get a const begin iterator over the particle/track four-momenta in this jet.
const_iterator end () const
 Get a const end iterator over the particle/track four-momenta in this jet.
vector< FourMomentum > & momenta ()
 Get the track momenta in this jet.
const vector< FourMomentum > & momenta () const
 Get the track momenta in this jet (const version).
vector< Particle > & particles ()
 Get the Rivet::Particles (full information) in this jet.
const vector< Particle > & particles () const
 Get the Rivet::Particles (full information) in this jet (const version).
size_t size () const
 Number of particles (tracks) in this jet.
Jet & setParticles (const vector< FourMomentum > &particles)
 Set the particles/tracks collection.
Jet & addParticle (const FourMomentum &particle)
 Add a particle/track to this jet.
Jet & addParticle (const Particle &particle)
 Add a particle/track to this jet.
bool containsParticle (const Particle &particle) const
 Check whether this jet contains a particular particle.
bool containsParticleId (PdgId pid) const
 Check whether this jet contains a certain particle type.
bool containsParticleId (const vector< PdgId > &pids) const
 Check whether this jet contains at least one of certain particle types.
bool containsCharm () const
 Check whether this jet contains a charm-flavoured hadron (or decay products from one).
bool containsBottom () const
 Check whether this jet contains a bottom-flavoured hadron (or decay products from one).
Jet & clear ()
 Reset this jet as empty.
double ptWeightedEta () const
double ptWeightedPhi () const
double eta () const
 Get the unweighted average $ \eta $ for this jet. (caches).
double phi () const
 Get the unweighted average $ \phi $ for this jet. (caches).
const FourMomentum & momentum () const
 Get equivalent single momentum four-vector. (caches).
double totalEnergy () const
 Get the total energy of this jet.
double neutralEnergy () const
 Get the energy carried in this jet by neutral particles.
double hadronicEnergy () const
 Get the energy carried in this jet by hadrons.
double ptSum () const
 Get the sum of the $ p_T $ values of the constituent tracks. (caches).
double EtSum () const
 Get the sum of the $ E_T $ values of the constituent tracks. (caches).

Private Member Functions

void _resetCaches () const
 Clear the internal cached values. Const because cache variables are mutable.
void _calcMomVector () const
 Calculate cached equivalent momentum vector. Const because cache variables are mutable.
void _calcPtAvgs () const

Private Attributes

std::vector< FourMomentum > _particles
 The particle tracks.
ParticleVector _fullParticles
 Full particle information including tracks, ID etc.
double _ptWeightedPhi
 Cached values of the $ p_T $-weighted $ \bar{\phi} $ and $ \bar{\eta} $.
double _ptWeightedEta
bool _okPtWeightedPhi
bool _okPtWeightedEta
FourMomentum _momentum
 Cached effective jet 4-vector.
bool _okMomentum

Detailed Description

A minimal class representing a jet of particles.

Definition at line 12 of file Jet.hh.

Member Typedef Documentation

typedef vector<FourMomentum>::const_iterator const_iterator

Define a Jet::const_iterator via a typedef.

Definition at line 22 of file Jet.hh.

typedef vector<FourMomentum>::iterator iterator

Define a Jet::iterator via a typedef.

Definition at line 19 of file Jet.hh.

Constructor & Destructor Documentation

Jet (  ) 

Constructor.

Definition at line 10 of file Jet.cc.

References Jet::clear().

00011     : ParticleBase()
00012   {
00013     clear();
00014   }

Member Function Documentation

void _calcMomVector (  )  const [private]

Calculate cached equivalent momentum vector. Const because cache variables are mutable.

Definition at line 194 of file Jet.cc.

References Jet::_momentum, Jet::_okMomentum, Jet::begin(), and Jet::end().

Referenced by Jet::momentum().

00194                                  {
00195     if (!_okMomentum) {
00196       _momentum = accumulate(begin(), end(), FourMomentum());
00197       _okMomentum = true;
00198     }
00199   }

void _calcPtAvgs (  )  const [private]

Internal caching method to calculate the average $ \eta $ and $ \phi $ for this jet, weighted by the $ p_T $ values of the constituent tracks. Const because cache variables are mutable.

Definition at line 202 of file Jet.cc.

References Jet::_okPtWeightedEta, Jet::_okPtWeightedPhi, Jet::_ptWeightedEta, Jet::_ptWeightedPhi, FourVector::azimuthalAngle(), Rivet::mapAngleMPiToPi(), Jet::momenta(), Jet::phi(), FourVector::pseudorapidity(), and FourMomentum::pT().

Referenced by Jet::ptWeightedEta(), and Jet::ptWeightedPhi().

00202                               {
00203     if (!_okPtWeightedEta || !_okPtWeightedPhi) {
00204       double ptwetasum(0.0), ptwdphisum(0.0), ptsum(0.0);
00205       double phi0 = phi();
00206       foreach (const FourMomentum& p, momenta()) {
00207         double pt = p.pT();
00208         ptsum += pt;
00209         ptwetasum += pt * p.pseudorapidity();
00210         ptwdphisum += pt * mapAngleMPiToPi(phi0 - p.azimuthalAngle());
00211       }
00212       _ptWeightedEta = ptwetasum/ptsum;
00213       _okPtWeightedEta = true;
00214       _ptWeightedPhi = mapAngleMPiToPi(phi0 + ptwdphisum/ptsum);
00215       _okPtWeightedPhi = true;
00216     }
00217   }

void _resetCaches (  )  const [private]

Clear the internal cached values. Const because cache variables are mutable.

Definition at line 187 of file Jet.cc.

References Jet::_okMomentum, Jet::_okPtWeightedEta, and Jet::_okPtWeightedPhi.

Referenced by Jet::addParticle(), Jet::clear(), and Jet::setParticles().

00187                                {
00188     _okPtWeightedPhi = false;
00189     _okPtWeightedEta = false;
00190     _okMomentum = false;
00191   }

Jet & addParticle ( const Particle &  particle  ) 

Add a particle/track to this jet.

Definition at line 31 of file Jet.cc.

References Jet::_fullParticles, Jet::_particles, Jet::_resetCaches(), and Particle::momentum().

00031                                                 {
00032     _fullParticles.push_back(particle);
00033     _particles.push_back(particle.momentum());
00034     _resetCaches();
00035     return *this;
00036   }

Jet & addParticle ( const FourMomentum &  particle  ) 

Add a particle/track to this jet.

Definition at line 24 of file Jet.cc.

References Jet::_particles, and Jet::_resetCaches().

Referenced by FastJets::_pseudojetsToJets().

00024                                                     {
00025     _particles.push_back(particle);
00026     _resetCaches();
00027     return *this;
00028   }

const_iterator begin (  )  const [inline]

Get a const begin iterator over the particle/track four-momenta in this jet.

Definition at line 35 of file Jet.hh.

References Jet::_particles.

00035                                  {
00036       return _particles.begin();
00037     }

iterator begin (  )  [inline]

Get a begin iterator over the particle/track four-momenta in this jet.

Definition at line 25 of file Jet.hh.

References Jet::_particles.

Referenced by Jet::_calcMomVector().

00025                      {
00026       return _particles.begin();
00027     }

Jet & clear (  ) 

Reset this jet as empty.

Definition at line 132 of file Jet.cc.

References Jet::_fullParticles, Jet::_particles, and Jet::_resetCaches().

Referenced by Jet::Jet().

00132                   {
00133     _particles.clear();
00134     _fullParticles.clear();
00135     _resetCaches();
00136     return *this;
00137   }

bool containsBottom (  )  const

Check whether this jet contains a bottom-flavoured hadron (or decay products from one).

Definition at line 115 of file Jet.cc.

References Rivet::BQUARK, Particle::genParticle(), Rivet::PID::hasBottom(), Rivet::PID::isHadron(), Rivet::particles(), Jet::particles(), Particle::pdgId(), and Rivet::pi.

Referenced by MC_TTBAR::analyze(), ExampleAnalysis::analyze(), and CDF_2008_S7782535::analyze().

00115                                  {
00116     foreach (const Particle& p, particles()) {
00117       const PdgId pid = p.pdgId();
00118       if (abs(pid) == BQUARK) return true;
00119       if (PID::isHadron(pid) && PID::hasBottom(pid)) return true;
00120       HepMC::GenVertex* gv = p.genParticle().production_vertex();
00121       if (gv) {
00122         foreach (const GenParticle* pi, Rivet::particles(gv, HepMC::ancestors)) {
00123           const PdgId pid2 = pi->pdg_id();
00124           if (PID::isHadron(pid2) && PID::hasBottom(pid2)) return true;
00125         }
00126       }
00127     }
00128     return false;
00129   }

bool containsCharm (  )  const

Check whether this jet contains a charm-flavoured hadron (or decay products from one).

Definition at line 98 of file Jet.cc.

References Rivet::CQUARK, Particle::genParticle(), Rivet::PID::hasCharm(), Rivet::PID::isHadron(), Rivet::particles(), Jet::particles(), Particle::pdgId(), and Rivet::pi.

00098                                 {
00099     foreach (const Particle& p, particles()) {
00100       const PdgId pid = p.pdgId();
00101       if (abs(pid) == CQUARK) return true;
00102       if (PID::isHadron(pid) && PID::hasCharm(pid)) return true;
00103       HepMC::GenVertex* gv = p.genParticle().production_vertex();
00104       if (gv) {
00105         foreach (const GenParticle* pi, Rivet::particles(gv, HepMC::ancestors)) {
00106           const PdgId pid2 = pi->pdg_id();
00107           if (PID::isHadron(pid2) && PID::hasCharm(pid2)) return true;
00108         }
00109       }
00110     }
00111     return false;
00112   }

bool containsParticle ( const Particle &  particle  )  const

Check whether this jet contains a particular particle.

Definition at line 39 of file Jet.cc.

References Particle::genParticle(), and Jet::particles().

00039                                                            {
00040     const int barcode = particle.genParticle().barcode();
00041     foreach (const Particle& p, particles()) {
00042       if (p.genParticle().barcode() == barcode) return true;
00043     }
00044     return false;
00045   }

bool containsParticleId ( const vector< PdgId > &  pids  )  const

Check whether this jet contains at least one of certain particle types.

Definition at line 56 of file Jet.cc.

References Jet::particles(), and Particle::pdgId().

00056                                                               {
00057     foreach (const Particle& p, particles()) {
00058       foreach (PdgId pid, pids) {
00059         if (p.pdgId() == pid) return true;
00060       }
00061     }
00062     return false;
00063   }

bool containsParticleId ( PdgId  pid  )  const

Check whether this jet contains a certain particle type.

Definition at line 48 of file Jet.cc.

References Jet::particles(), and Particle::pdgId().

00048                                               {
00049     foreach (const Particle& p, particles()) {
00050       if (p.pdgId() == pid) return true;
00051     }
00052     return false;
00053   }

const_iterator end (  )  const [inline]

Get a const end iterator over the particle/track four-momenta in this jet.

Definition at line 40 of file Jet.hh.

References Jet::_particles.

00040                                {
00041       return _particles.end();
00042     }

iterator end (  )  [inline]

Get an end iterator over the particle/track four-momenta in this jet.

Definition at line 30 of file Jet.hh.

References Jet::_particles.

Referenced by Jet::_calcMomVector().

00030                    {
00031       return _particles.end();
00032     }

double eta (  )  const

Get the unweighted average $ \eta $ for this jet. (caches).

Definition at line 154 of file Jet.cc.

References FourVector::eta(), and Jet::momentum().

Referenced by STAR_2006_S6870392::analyze(), and ATLAS_2010_S8919674::analyze().

00154                         {
00155     return momentum().eta();
00156 
00157   }

double EtSum (  )  const

Get the sum of the $ E_T $ values of the constituent tracks. (caches).

Definition at line 182 of file Jet.cc.

References FourMomentum::Et(), and Jet::momentum().

Referenced by CDF_2004_S5839831::analyze(), Rivet::cmpJetsByEt(), and Rivet::cmpJetsByEtDesc().

00182                           {
00183     return momentum().Et();
00184   }

double hadronicEnergy (  )  const

Get the energy carried in this jet by hadrons.

Definition at line 86 of file Jet.cc.

References FourMomentum::E(), Rivet::PID::isHadron(), Particle::momentum(), Jet::particles(), and Particle::pdgId().

00086                                    {
00087     double e_hadr = 0.0;
00088     foreach (const Particle& p, particles()) {
00089       const PdgId pid = p.pdgId();
00090       if (PID::isHadron(pid)) {
00091         e_hadr += p.momentum().E();
00092       }
00093     }
00094     return e_hadr;
00095   }

const vector<FourMomentum>& momenta (  )  const [inline]

Get the track momenta in this jet (const version).

Definition at line 50 of file Jet.hh.

References Jet::_particles.

00050                                                 {
00051       return _particles;
00052     }

vector<FourMomentum>& momenta (  )  [inline]

Get the track momenta in this jet.

Definition at line 45 of file Jet.hh.

References Jet::_particles.

Referenced by Jet::_calcPtAvgs().

00045                                     {
00046       return _particles;
00047     }

const FourMomentum & momentum (  )  const [virtual]

Get equivalent single momentum four-vector. (caches).

Implements ParticleBase.

Definition at line 165 of file Jet.cc.

References Jet::_calcMomVector(), and Jet::_momentum.

Referenced by CDF_1996_S3349578::_fiveJetAnalysis(), D0_1996_S3214044::_fourJetAnalysis(), CDF_1996_S3349578::_fourJetAnalysis(), D0_1996_S3214044::_threeJetAnalysis(), CDF_1996_S3349578::_threeJetAnalysis(), ZEUS_2001_S4815815::analyze(), STAR_2009_UE_HELEN::analyze(), STAR_2006_S6870392::analyze(), MC_ZZJETS::analyze(), MC_WWJETS::analyze(), MC_TTBAR::analyze(), MC_SUSY::analyze(), MC_PHOTONJETUE::analyze(), MC_JetAnalysis::analyze(), MC_DIJET::analyze(), D0_2009_S8349509::analyze(), D0_2009_S8202443::analyze(), D0_2008_S7863608::analyze(), D0_2008_S7662670::analyze(), D0_2008_S6879055::analyze(), D0_1996_S3324664::analyze(), D0_1996_S3214044::analyze(), CMS_2011_S8957746::analyze(), CDF_2008_S7828950::analyze(), CDF_2008_S7782535::analyze(), CDF_2008_S7541902::analyze(), CDF_2008_S7540469::analyze(), CDF_2007_S7057202::analyze(), CDF_2006_S6450792::analyze(), CDF_2004_S5839831::analyze(), CDF_2001_S4563131::analyze(), CDF_1998_S3618439::analyze(), CDF_1997_S3541940::analyze(), CDF_1996_S3349578::analyze(), CDF_1996_S3108457::analyze(), CDF_1993_S2742446::analyze(), ATLAS_2011_S9019561::analyze(), ATLAS_2011_S8983313::analyze(), ATLAS_2011_S8971293::analyze(), ATLAS_2011_CONF_2011_090::analyze(), ATLAS_2010_S8919674::analyze(), ATLAS_2010_S8817804::analyze(), ATLAS_2010_CONF_2010_049::analyze(), JetShape::calc(), Rivet::cmpJetsByAscAbsPseudorapidity(), Rivet::cmpJetsByAscAbsRapidity(), Rivet::cmpJetsByAscE(), Rivet::cmpJetsByAscP(), Rivet::cmpJetsByAscPseudorapidity(), Rivet::cmpJetsByAscRapidity(), Rivet::cmpJetsByDescAbsPseudorapidity(), Rivet::cmpJetsByDescAbsRapidity(), Rivet::cmpJetsByDescPseudorapidity(), Rivet::cmpJetsByDescRapidity(), Rivet::cmpJetsByE(), Rivet::cmpJetsByP(), Rivet::deltaEta(), Rivet::deltaPhi(), Rivet::deltaR(), Jet::eta(), Jet::EtSum(), JetAlg::jets(), Jet::phi(), Jet::ptSum(), and Jet::totalEnergy().

00165                                           {
00166     _calcMomVector();
00167     return _momentum;
00168   }

double neutralEnergy (  )  const

Get the energy carried in this jet by neutral particles.

Definition at line 74 of file Jet.cc.

References FourMomentum::E(), Particle::momentum(), Jet::particles(), Particle::pdgId(), and Rivet::PID::threeCharge().

Referenced by STAR_2009_UE_HELEN::analyze().

00074                                   {
00075     double e_neutral = 0.0;
00076     foreach (const Particle& p, particles()) {
00077       const PdgId pid = p.pdgId();
00078       if (PID::threeCharge(pid) == 0) {
00079         e_neutral += p.momentum().E();
00080       }
00081     }
00082     return e_neutral;
00083   }

const vector<Particle>& particles (  )  const [inline]

Get the Rivet::Particles (full information) in this jet (const version).

Definition at line 60 of file Jet.hh.

References Jet::_fullParticles.

00060                                               {
00061       return _fullParticles;
00062     }

vector<Particle>& particles (  )  [inline]

Get the Rivet::Particles (full information) in this jet.

Definition at line 55 of file Jet.hh.

References Jet::_fullParticles.

Referenced by ATLAS_2010_CONF_2010_049::analyze(), JetShape::calc(), Jet::containsBottom(), Jet::containsCharm(), Jet::containsParticle(), Jet::containsParticleId(), Jet::hadronicEnergy(), and Jet::neutralEnergy().

00055                                   {
00056       return _fullParticles;
00057     }

double phi (  )  const

Get the unweighted average $ \phi $ for this jet. (caches).

Definition at line 160 of file Jet.cc.

References Jet::momentum(), and FourVector::phi().

Referenced by Jet::_calcPtAvgs().

00160                         {
00161     return momentum().phi();
00162   }

double ptSum (  )  const

Get the sum of the $ p_T $ values of the constituent tracks. (caches).

Definition at line 177 of file Jet.cc.

References Jet::momentum(), and FourMomentum::pT().

Referenced by CDF_2001_S4751469::analyze(), Rivet::cmpJetsByAscPt(), and Rivet::cmpJetsByPt().

00177                           {
00178     return momentum().pT();
00179   }

double ptWeightedEta (  )  const

Get the average $ \eta $ for this jet, with the average weighted by the $ p_T $ values of the constituent tracks. (caches)

Definition at line 140 of file Jet.cc.

References Jet::_calcPtAvgs(), Jet::_okPtWeightedEta, and Jet::_ptWeightedEta.

00140                                   {
00141     _calcPtAvgs();
00142     assert(_okPtWeightedEta);
00143     return _ptWeightedEta;
00144   }

double ptWeightedPhi (  )  const

Get the average $ \phi $ for this jet, with the average weighted by the $ p_T $ values of the constituent tracks. (caches)

Definition at line 147 of file Jet.cc.

References Jet::_calcPtAvgs(), Jet::_okPtWeightedPhi, and Jet::_ptWeightedPhi.

Referenced by CDF_2001_S4751469::analyze().

00147                                   {
00148     _calcPtAvgs();
00149     assert(_okPtWeightedPhi);
00150     return _ptWeightedPhi;
00151   }

Jet & setParticles ( const vector< FourMomentum > &  particles  ) 

Set the particles/tracks collection.

Definition at line 17 of file Jet.cc.

References Jet::_particles, and Jet::_resetCaches().

00017                                                               {
00018     _particles = particles;
00019     _resetCaches();
00020     return *this;
00021   }

size_t size (  )  const [inline]

Number of particles (tracks) in this jet.

Definition at line 65 of file Jet.hh.

References Jet::_particles.

00065                         {
00066       return _particles.size();
00067     }

double totalEnergy (  )  const

Get the total energy of this jet.

Todo:
Jet::containsMatch(Matcher m) { ... if m(pid) return true; ... }

Definition at line 69 of file Jet.cc.

References FourMomentum::E(), and Jet::momentum().

Referenced by STAR_2009_UE_HELEN::analyze().

00069                                 {
00070     return momentum().E();
00071   }

Member Data Documentation

ParticleVector _fullParticles [private]

Full particle information including tracks, ID etc.

Definition at line 159 of file Jet.hh.

Referenced by Jet::addParticle(), Jet::clear(), and Jet::particles().

FourMomentum _momentum [mutable, private]

Cached effective jet 4-vector.

Definition at line 166 of file Jet.hh.

Referenced by Jet::_calcMomVector(), and Jet::momentum().

bool _okMomentum [mutable, private]

Definition at line 167 of file Jet.hh.

Referenced by Jet::_calcMomVector(), and Jet::_resetCaches().

bool _okPtWeightedEta [mutable, private]

Definition at line 163 of file Jet.hh.

Referenced by Jet::_calcPtAvgs(), Jet::_resetCaches(), and Jet::ptWeightedEta().

bool _okPtWeightedPhi [mutable, private]

Definition at line 163 of file Jet.hh.

Referenced by Jet::_calcPtAvgs(), Jet::_resetCaches(), and Jet::ptWeightedPhi().

std::vector<FourMomentum> _particles [private]

The particle tracks.

Definition at line 156 of file Jet.hh.

Referenced by Jet::addParticle(), Jet::begin(), Jet::clear(), Jet::end(), Jet::momenta(), Jet::setParticles(), and Jet::size().

double _ptWeightedEta [mutable, private]

Definition at line 162 of file Jet.hh.

Referenced by Jet::_calcPtAvgs(), and Jet::ptWeightedEta().

double _ptWeightedPhi [mutable, private]

Cached values of the $ p_T $-weighted $ \bar{\phi} $ and $ \bar{\eta} $.

Definition at line 162 of file Jet.hh.

Referenced by Jet::_calcPtAvgs(), and Jet::ptWeightedPhi().

The documentation for this class was generated from the following files: