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MaterialEffects Class Reference

#include <FastSimulation/MaterialEffects/interface/MaterialEffects.h>

List of all members.

Public Member Functions
double	energyLoss () const
	Return the energy loss by ionization in the current layer.
EnergyLossSimulator *	energyLossSimulator () const
	Return the Energy Loss engine.
void	interact (FSimEvent &simEvent, const TrackerLayer &layer, ParticlePropagator &PP, unsigned i)
	Steer the various interaction processes in the Tracker Material and update the FSimEvent.
	MaterialEffects (const edm::ParameterSet &matEff, const RandomEngine *engine)
	Constructor.
MultipleScatteringSimulator *	multipleScatteringSimulator () const
	Return the Multiple Scattering engine.
void	save ()
	Save nuclear interaction information.
double	thickness () const
	Return the thickness of the current layer.
	~MaterialEffects ()
	Default destructor.
Private Member Functions
GlobalVector	normalVector (const TrackerLayer &layer, ParticlePropagator &myTrack) const
	The vector normal to the surface traversed.
double	radLengths (const TrackerLayer &layer, ParticlePropagator &myTrack)
	The number of radiation lengths traversed.
Private Attributes
BremsstrahlungSimulator *	Bremsstrahlung
EnergyLossSimulator *	EnergyLoss
MultipleScatteringSimulator *	MultipleScattering
NuclearInteractionSimulator *	NuclearInteraction
PairProductionSimulator *	PairProduction
double	pTmin
const RandomEngine *	random
double	theEnergyLoss
GlobalVector	theNormalVector
double	theTECFudgeFactor
double	theThickness

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Detailed Description

Definition at line 48 of file MaterialEffects.h.

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Constructor & Destructor Documentation

MaterialEffects::MaterialEffects	(	const edm::ParameterSet &	matEff,
		const RandomEngine *	engine
	)

Constructor.

Definition at line 22 of file MaterialEffects.cc.

References funct::A, Bremsstrahlung, EnergyLoss, edm::ParameterSet::getParameter(), edm::ParameterSet::getUntrackedParameter(), i, outputToXml::inputFile, j, MultipleScattering, NuclearInteraction, PairProduction, pTmin, random, and theTECFudgeFactor.

  : PairProduction(0), Bremsstrahlung(0), 
    MultipleScattering(0), EnergyLoss(0), 
    NuclearInteraction(0),
    pTmin(999.), random(engine)
{
  // Set the minimal photon energy for a Brem from e+/-

  bool doPairProduction     = matEff.getParameter<bool>("PairProduction");
  bool doBremsstrahlung     = matEff.getParameter<bool>("Bremsstrahlung");
  bool doEnergyLoss         = matEff.getParameter<bool>("EnergyLoss");
  bool doMultipleScattering = matEff.getParameter<bool>("MultipleScattering");
  bool doNuclearInteraction = matEff.getParameter<bool>("NuclearInteraction");

  double A = matEff.getParameter<double>("A");
  double Z = matEff.getParameter<double>("Z");
  double density = matEff.getParameter<double>("Density");
  double radLen = matEff.getParameter<double>("RadiationLength");
  
  // Set the minimal pT before giving up the dE/dx treatment

  if ( doPairProduction ) { 

    double photonEnergy = matEff.getParameter<double>("photonEnergy");
    PairProduction = new PairProductionSimulator(photonEnergy,
                                                 random);

  }

  if ( doBremsstrahlung ) { 

    double bremEnergy = matEff.getParameter<double>("bremEnergy");
    double bremEnergyFraction = matEff.getParameter<double>("bremEnergyFraction");
    Bremsstrahlung = new BremsstrahlungSimulator(bremEnergy,
                                                 bremEnergyFraction,
                                                 random);

  }

  if ( doEnergyLoss ) { 

    pTmin = matEff.getParameter<double>("pTmin");
    EnergyLoss = new EnergyLossSimulator(random,A,Z,density,radLen);

  }

  if ( doMultipleScattering ) { 
    
    MultipleScattering = new MultipleScatteringSimulator(random,A,Z,density,radLen);

  }

  if ( doNuclearInteraction ) { 

    // The energies simulated
    std::vector<double> pionEnergies 
      = matEff.getUntrackedParameter<std::vector<double> >("pionEnergies");

    // The particle types simulated
    std::vector<int> pionTypes 
      = matEff.getUntrackedParameter<std::vector<int> >("pionTypes");

    // The corresponding particle names
    std::vector<std::string> pionNames 
      = matEff.getUntrackedParameter<std::vector<std::string> >("pionNames");

    // The corresponding particle masses
    std::vector<double> pionMasses 
      = matEff.getUntrackedParameter<std::vector<double> >("pionMasses");

    // The smallest momentum for inelastic interactions
    std::vector<double> pionPMin 
      = matEff.getUntrackedParameter<std::vector<double> >("pionMinP");

    // The interaction length / radiation length ratio for each particle type
    std::vector<double> lengthRatio 
      = matEff.getParameter<std::vector<double> >("lengthRatio");
    //    std::map<int,double> lengthRatio;
    //    for ( unsigned i=0; i<theLengthRatio.size(); ++i )
    //      lengthRatio[ pionTypes[i] ] = theLengthRatio[i];

    // A global fudge factor for TEC layers (which apparently do not react to 
    // hadrons the same way as all other layers...
    theTECFudgeFactor = matEff.getParameter<double>("fudgeFactor");

    // The evolution of the interaction lengths with energy
    std::vector<double> theRatios  
      = matEff.getUntrackedParameter<std::vector<double> >("ratios");
    //std::map<int,std::vector<double> > ratios;
    //for ( unsigned i=0; i<pionTypes.size(); ++i ) { 
    //  for ( unsigned j=0; j<pionEnergies.size(); ++j ) { 
    //  ratios[ pionTypes[i] ].push_back(theRatios[ i*pionEnergies.size() + j ]);
    //  }
    //}
    std::vector< std::vector<double> > ratios;
    ratios.resize(pionTypes.size());
    for ( unsigned i=0; i<pionTypes.size(); ++i ) { 
      for ( unsigned j=0; j<pionEnergies.size(); ++j ) { 
        ratios[i].push_back(theRatios[ i*pionEnergies.size() + j ]);
      }
    }

    // The smallest momentum for elastic interactions
    double pionEnergy 
      = matEff.getParameter<double>("pionEnergy");

    // The algorithm to compute the distance between primary and secondaries
    // when a nuclear interaction occurs
    unsigned distAlgo 
      = matEff.getParameter<unsigned>("distAlgo");
    double distCut 
      = matEff.getParameter<double>("distCut");

    // The file to read the starting interaction in each files
    // (random reproducibility in case of a crash)
    std::string inputFile 
      = matEff.getUntrackedParameter<std::string>("inputFile");

    // Build the ID map (i.e., what is to be considered as a proton, etc...)
    std::map<int,int> idMap;
    // Protons
    std::vector<int> idProtons 
      = matEff.getUntrackedParameter<std::vector<int> >("protons");
    for ( unsigned i=0; i<idProtons.size(); ++i ) 
      idMap[idProtons[i]] = 2212;
    // Anti-Protons
    std::vector<int> idAntiProtons 
      = matEff.getUntrackedParameter<std::vector<int> >("antiprotons");
    for ( unsigned i=0; i<idAntiProtons.size(); ++i ) 
      idMap[idAntiProtons[i]] = -2212;
    // Neutrons
    std::vector<int> idNeutrons 
      = matEff.getUntrackedParameter<std::vector<int> >("neutrons");
    for ( unsigned i=0; i<idNeutrons.size(); ++i ) 
      idMap[idNeutrons[i]] = 2112;
    // Anti-Neutrons
    std::vector<int> idAntiNeutrons 
      = matEff.getUntrackedParameter<std::vector<int> >("antineutrons");
    for ( unsigned i=0; i<idAntiNeutrons.size(); ++i ) 
      idMap[idAntiNeutrons[i]] = -2112;
    // K0L's
    std::vector<int> idK0Ls 
      = matEff.getUntrackedParameter<std::vector<int> >("K0Ls");
    for ( unsigned i=0; i<idK0Ls.size(); ++i ) 
      idMap[idK0Ls[i]] = 130;
    // K+'s
    std::vector<int> idKplusses 
      = matEff.getUntrackedParameter<std::vector<int> >("Kplusses");
    for ( unsigned i=0; i<idKplusses.size(); ++i ) 
      idMap[idKplusses[i]] = 321;
    // K-'s
    std::vector<int> idKminusses 
      = matEff.getUntrackedParameter<std::vector<int> >("Kminusses");
    for ( unsigned i=0; i<idKminusses.size(); ++i ) 
      idMap[idKminusses[i]] = -321;
    // pi+'s
    std::vector<int> idPiplusses 
      = matEff.getUntrackedParameter<std::vector<int> >("Piplusses");
    for ( unsigned i=0; i<idPiplusses.size(); ++i ) 
      idMap[idPiplusses[i]] = 211;
    // pi-'s
    std::vector<int> idPiminusses 
      = matEff.getUntrackedParameter<std::vector<int> >("Piminusses");
    for ( unsigned i=0; i<idPiminusses.size(); ++i ) 
      idMap[idPiminusses[i]] = -211;

    // Construction
    NuclearInteraction = 
      new NuclearInteractionSimulator(pionEnergies, pionTypes, pionNames, 
                                      pionMasses, pionPMin, pionEnergy, 
                                      lengthRatio, ratios, idMap, 
                                      inputFile, distAlgo, distCut, random);
  }

}

MaterialEffects::~MaterialEffects

(

)

Default destructor.

Definition at line 200 of file MaterialEffects.cc.

References Bremsstrahlung, EnergyLoss, MultipleScattering, NuclearInteraction, and PairProduction.

                                  {

  if ( PairProduction ) delete PairProduction;
  if ( Bremsstrahlung ) delete Bremsstrahlung;
  if ( EnergyLoss ) delete EnergyLoss;
  if ( MultipleScattering ) delete MultipleScattering;
  if ( NuclearInteraction ) delete NuclearInteraction;

}

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Member Function Documentation

double MaterialEffects::energyLoss

(

)

const [inline]

Return the energy loss by ionization in the current layer.

Definition at line 74 of file MaterialEffects.h.

References theEnergyLoss.

Referenced by TrajectoryManager::createPSimHits().

{ return theEnergyLoss; }

EnergyLossSimulator* MaterialEffects::energyLossSimulator

(

)

const [inline]

Return the Energy Loss engine.

Definition at line 82 of file MaterialEffects.h.

References EnergyLoss.

Referenced by MuonSimHitProducer::applyMaterialEffects().

                                                          { 
    return EnergyLoss;
  }

void MaterialEffects::interact	(	FSimEvent &	simEvent,
		const TrackerLayer &	layer,
		ParticlePropagator &	PP,
		unsigned	i
	)

Steer the various interaction processes in the Tracker Material and update the FSimEvent.

Energy loss ---------------

Multiple scattering -----------------------

Definition at line 210 of file MaterialEffects.cc.

References funct::abs(), FBaseSimEvent::addSimTrack(), FBaseSimEvent::addSimVertex(), MaterialEffectsSimulator::beginDaughters(), Bremsstrahlung, RawParticle::charge(), MaterialEffectsSimulator::closestDaughterId(), MaterialEffectsSimulator::endDaughters(), EnergyLoss, TrackerLayer::layerNumber(), MultipleScattering, MaterialEffectsSimulator::nDaughters(), normalVector(), NuclearInteraction, PairProduction, RawParticle::pid(), FSimVertex::position(), pTmin, radLengths(), FSimTrack::setClosestDaughterId(), MaterialEffectsSimulator::setNormalVector(), theEnergyLoss, theNormalVector, theTECFudgeFactor, FBaseSimEvent::track(), MaterialEffectsSimulator::updateState(), RawParticle::vertex(), and FSimTrack::vertex().

Referenced by TrajectoryManager::reconstruct().

                                                {

  MaterialEffectsSimulator::RHEP_const_iter DaughterIter;
  double radlen;
  theEnergyLoss = 0;
  theNormalVector = normalVector(layer,myTrack);
  radlen = radLengths(layer,myTrack);

//-------------------
//  Photon Conversion
//-------------------

  if ( PairProduction && myTrack.pid()==22 ) {
    
    //
    PairProduction->updateState(myTrack,radlen);

    if ( PairProduction->nDaughters() ) {       
      //add a vertex to the mother particle
      int ivertex = mySimEvent.addSimVertex(myTrack.vertex(),itrack);
      
      // This was a photon that converted
      for ( DaughterIter = PairProduction->beginDaughters();
            DaughterIter != PairProduction->endDaughters(); 
            ++DaughterIter) {

        mySimEvent.addSimTrack(&(*DaughterIter), ivertex);

      }
      // The photon converted. Return.
      return;
    }
  }

  if ( myTrack.pid() == 22 ) return;

//------------------------
//   Nuclear interactions
//------------------------ 

  if ( NuclearInteraction && abs(myTrack.pid()) > 100 
                          && abs(myTrack.pid()) < 1000000) { 

    // Simulate a nuclear interaction
    double factor = 1.0;
    if (layer.layerNumber() >= 19 && layer.layerNumber() <= 27 ) 
      factor = theTECFudgeFactor;
    NuclearInteraction->updateState(myTrack,radlen*factor);

    if ( NuclearInteraction->nDaughters() ) { 

      //add a end vertex to the mother particle
      int ivertex = mySimEvent.addSimVertex(myTrack.vertex(),itrack);
      
      // This was a hadron that interacted inelastically
      int idaugh = 0;
      for ( DaughterIter = NuclearInteraction->beginDaughters();
            DaughterIter != NuclearInteraction->endDaughters(); 
            ++DaughterIter) {

        // The daughter in the event
        int daughId = mySimEvent.addSimTrack(&(*DaughterIter), ivertex);
        
        // Store the closest daughter in the mother info (for later tracking purposes)
        if ( NuclearInteraction->closestDaughterId() == idaugh++ ) {
          if ( mySimEvent.track(itrack).vertex().position().Pt() < 4.0 ) 
            mySimEvent.track(itrack).setClosestDaughterId(daughId);
        }

      }
      // The hadron is destroyed. Return.
      return;
    }
    
  }

  if ( myTrack.charge() == 0 ) return;

  if ( !Bremsstrahlung && !EnergyLoss && !MultipleScattering ) return;

//----------------
//  Bremsstrahlung
//----------------

  if ( Bremsstrahlung && abs(myTrack.pid())==11 ) {
        
    Bremsstrahlung->updateState(myTrack,radlen);

    if ( Bremsstrahlung->nDaughters() ) {
      
      // Add a vertex, but do not attach it to the electron, because it 
      // continues its way...
      int ivertex = mySimEvent.addSimVertex(myTrack.vertex(),itrack);

      for ( DaughterIter = Bremsstrahlung->beginDaughters();
            DaughterIter != Bremsstrahlung->endDaughters(); 
            ++DaughterIter) {
        mySimEvent.addSimTrack(&(*DaughterIter), ivertex);

      }
      
    }
    
  } 



  if ( EnergyLoss )
  {
    theEnergyLoss = myTrack.E();
    EnergyLoss->updateState(myTrack,radlen);
    theEnergyLoss -= myTrack.E();
  }
  


  if ( MultipleScattering && myTrack.Pt() > pTmin ) {
    //    MultipleScattering->setNormalVector(normalVector(layer,myTrack));
    MultipleScattering->setNormalVector(theNormalVector);
    MultipleScattering->updateState(myTrack,radlen);
  }
    
}

MultipleScatteringSimulator* MaterialEffects::multipleScatteringSimulator

(

)

const [inline]

Return the Multiple Scattering engine.

Definition at line 77 of file MaterialEffects.h.

References MultipleScattering.

Referenced by MuonSimHitProducer::applyMaterialEffects().

                                                                          { 
    return MultipleScattering;
  }

GlobalVector MaterialEffects::normalVector	(	const TrackerLayer &	layer,
		ParticlePropagator &	myTrack
	)			const [private]

The vector normal to the surface traversed.

Definition at line 385 of file MaterialEffects.cc.

References TrackerLayer::disk(), TrackerLayer::forward(), Plane::normalVector(), RawParticle::R(), RawParticle::X(), and RawParticle::Y().

Referenced by interact().

                                                                  {
  return layer.forward() ?  
    layer.disk()->normalVector() :
    GlobalVector(myTrack.X(),myTrack.Y(),0.)/myTrack.R();
}

double MaterialEffects::radLengths	(	const TrackerLayer &	layer,
		ParticlePropagator &	myTrack
	)			[private]

The number of radiation lengths traversed.

Definition at line 344 of file MaterialEffects.cc.

References TrackerLayer::forward(), TrackerLayer::fudgeFactor(), TrackerLayer::fudgeMax(), TrackerLayer::fudgeMin(), TrackerLayer::fudgeNumber(), Surface::mediumProperties(), P, RawParticle::R(), MediumProperties::radLen(), TrackerLayer::surface(), theNormalVector, theThickness, and RawParticle::Z().

Referenced by interact().

                                                         {

  // Thickness of layer
  theThickness = layer.surface().mediumProperties()->radLen();

  GlobalVector P(myTrack.Px(),myTrack.Py(),myTrack.Pz());
  
  // Effective length of track inside layer (considering crossing angle)
  //  double radlen = theThickness / fabs(P.dot(theNormalVector)/(P.mag()*theNormalVector.mag()));
  double radlen = theThickness / fabs(P.dot(theNormalVector)) * P.mag();

  // This is a series of fudge factors (from the geometry description), 
  // to describe the layer inhomogeneities (services, cables, supports...)
  double rad = myTrack.R();
  double zed = fabs(myTrack.Z());

  double factor = 1;

  // Are there fudge factors for this layer
  if ( layer.fudgeNumber() ) 

    // If yes, loop on them
    for ( unsigned int iLayer=0; iLayer < layer.fudgeNumber(); ++iLayer ) { 

      // Apply to R if forward layer, to Z if barrel layer
      if ( (  layer.forward() && layer.fudgeMin(iLayer) < rad && rad < layer.fudgeMax(iLayer) )  ||
           ( !layer.forward() && layer.fudgeMin(iLayer) < zed && zed < layer.fudgeMax(iLayer) ) ) {
        factor = layer.fudgeFactor(iLayer);
        break;
      }
    
  }

  theThickness *= factor;

  return radlen * factor;

}

void MaterialEffects::save

(

)

Save nuclear interaction information.

Definition at line 393 of file MaterialEffects.cc.

References NuclearInteraction, and NuclearInteractionSimulator::save().

Referenced by TrajectoryManager::reconstruct().

                      { 

  // Save current nuclear interactions in the event libraries.
  if ( NuclearInteraction ) NuclearInteraction->save();

}

double MaterialEffects::thickness

(

)

const [inline]

Return the thickness of the current layer.

Definition at line 71 of file MaterialEffects.h.

References theThickness.

Referenced by TrajectoryManager::createPSimHits().

{ return theThickness; }

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Member Data Documentation

BremsstrahlungSimulator* MaterialEffects::Bremsstrahlung [private]

Definition at line 100 of file MaterialEffects.h.

Referenced by interact(), MaterialEffects(), and ~MaterialEffects().

EnergyLossSimulator* MaterialEffects::EnergyLoss [private]

Definition at line 102 of file MaterialEffects.h.

Referenced by energyLossSimulator(), interact(), MaterialEffects(), and ~MaterialEffects().

MultipleScatteringSimulator* MaterialEffects::MultipleScattering [private]

Definition at line 101 of file MaterialEffects.h.

Referenced by interact(), MaterialEffects(), multipleScatteringSimulator(), and ~MaterialEffects().

NuclearInteractionSimulator* MaterialEffects::NuclearInteraction [private]

Definition at line 103 of file MaterialEffects.h.

Referenced by interact(), MaterialEffects(), save(), and ~MaterialEffects().

PairProductionSimulator* MaterialEffects::PairProduction [private]

Definition at line 99 of file MaterialEffects.h.

Referenced by interact(), MaterialEffects(), and ~MaterialEffects().

double MaterialEffects::pTmin [private]

Definition at line 106 of file MaterialEffects.h.

Referenced by interact(), and MaterialEffects().

const RandomEngine* MaterialEffects::random [private]

Definition at line 116 of file MaterialEffects.h.

Referenced by MaterialEffects().

double MaterialEffects::theEnergyLoss [private]

Definition at line 109 of file MaterialEffects.h.

Referenced by energyLoss(), and interact().

GlobalVector MaterialEffects::theNormalVector [private]

Definition at line 107 of file MaterialEffects.h.

Referenced by interact(), and radLengths().

double MaterialEffects::theTECFudgeFactor [private]

Definition at line 110 of file MaterialEffects.h.

Referenced by interact(), and MaterialEffects().

double MaterialEffects::theThickness [private]

Definition at line 108 of file MaterialEffects.h.

Referenced by radLengths(), and thickness().

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

• FastSimulation/MaterialEffects/interface/MaterialEffects.h
• FastSimulation/MaterialEffects/src/MaterialEffects.cc

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