EDepSim::HitSegment Class Reference

#include <EDepSimHitSegment.hh>

Inheritance diagram for EDepSim::HitSegment:

Public Types
typedef G4THitsCollection< EDepSim::HitSegment >	HitSegmentCollection

Public Member Functions
	HitSegment (double maxSagitta=1 *CLHEP::mm, double maxLength=5 *CLHEP::mm)
	HitSegment (const EDepSim::HitSegment &rhs)
virtual	~HitSegment ()
void *	operator new (size_t)
void	operator delete (void *)
virtual void	AddStep (G4Step *theStep)
	Add the effects of a part of a step to this hit. More...
virtual bool	SameHit (G4Step *theStep)
virtual void	Draw ()
virtual void	Print ()
virtual void	Draw (const char *)
virtual void	Print (const char *) const
std::vector< int > &	GetContributors ()
	Provide public access to the contributors for internal G4 classes. More...
virtual double	GetLength () const
int	GetContributor (int i) const
int	GetContributorCount () const
int	GetPrimaryTrajectoryId (void) const
double	GetEnergyDeposit (void) const
	Get the total energy deposited in this hit. More...
double	GetSecondaryDeposit (void) const
double	GetTrackLength (void) const
const G4LorentzVector &	GetStart () const
	The position of the starting point. More...
const G4LorentzVector &	GetStop () const
	The position of the stopping point. More...
void	ls (std::string="") const
	Print the hit information. More...

Protected Member Functions
int	FindPrimaryId (G4Track *theTrack)
double	FindSagitta (G4Step *theStep)
double	FindSeparation (G4Step *theStep)

Private Attributes
double	fMaxSagitta
	The sagitta tolerance for the segment. More...
double	fMaxLength
	The maximum length between the start and stop points of the segment. More...
std::vector< int >	fContributors
int	fPrimaryId
	The track id of the primary particle. More...
double	fEnergyDeposit
	The total energy deposit in this hit. More...
double	fSecondaryDeposit
double	fTrackLength
G4LorentzVector	fStart
	The starting position of the segment. More...
G4LorentzVector	fStop
	The stopping position of the segment. More...
EDepSim::VolumeId	fHitVolume
	The G4 physical volume that contains the hit. More...
std::vector< G4ThreeVector >	fPath

Detailed Description

Definition at line 31 of file EDepSimHitSegment.hh.

Member Typedef Documentation

typedef G4THitsCollection<EDepSim::HitSegment> EDepSim::HitSegment::HitSegmentCollection

Definition at line 42 of file EDepSimHitSegment.hh.

Constructor & Destructor Documentation

EDepSim::HitSegment::HitSegment	(	double	maxSagitta = 1*CLHEP::mm,
		double	maxLength = 5*CLHEP::mm
	)

Create a new hit segment with a maximum allowed sagitta and length. The default values are set so that normally, a scintillator element will only have a single hit for a through going track (& delta-rays).

Definition at line 36 of file EDepSimHitSegment.cc.

    : fMaxSagitta(maxSagitta), fMaxLength(maxLength),
      fPrimaryId(0), fEnergyDeposit(0), fSecondaryDeposit(0), fTrackLength(0), 
      fStart(0,0,0,0), fStop(0,0,0,0) {
    fPath.reserve(500);
}

EDepSim::HitSegment::HitSegment

(

const EDepSim::HitSegment &

rhs

)

Definition at line 43 of file EDepSimHitSegment.cc.

    : G4VHit(rhs), 
      fMaxSagitta(rhs.fMaxSagitta), fMaxLength(rhs.fMaxLength),
      fContributors(rhs.fContributors), fPrimaryId(rhs.fPrimaryId),
      fEnergyDeposit(rhs.fEnergyDeposit),
      fSecondaryDeposit(rhs.fSecondaryDeposit),
      fTrackLength(rhs.fTrackLength), 
      fStart(rhs.fStart), fStop(rhs.fStop) {}

EDepSim::HitSegment::~HitSegment ( )

virtual

Definition at line 53 of file EDepSimHitSegment.cc.

{ }

Member Function Documentation

void EDepSim::HitSegment::AddStep ( G4Step *  theStep )

virtual

Add the effects of a part of a step to this hit.

First make sure the step has been initialized.

Definition at line 104 of file EDepSimHitSegment.cc.

                                               {
    G4TouchableHandle touchable 
        = theStep->GetPreStepPoint()->GetTouchableHandle();
    G4ThreeVector prePos = theStep->GetPreStepPoint()->GetPosition();
    G4ThreeVector postPos = theStep->GetPostStepPoint()->GetPosition();
    G4StepStatus stepStatus = theStep->GetPostStepPoint()->GetStepStatus();
    G4ParticleDefinition* particle =  theStep->GetTrack()->GetDefinition();
    double energyDeposit = theStep->GetTotalEnergyDeposit();
    double stepLength = (prePos-postPos).mag();
    double trackLength = theStep->GetStepLength();
    double nonIonizingDeposit = theStep->GetNonIonizingEnergyDeposit();
    
    if (trackLength < 0.75*stepLength || trackLength < stepLength - 1*mm) {
        EDepSimWarn("Track length shorter than step: " 
                 << trackLength/mm << " mm "
                 << "<" << stepLength/mm << " mm");
        EDepSimWarn("    Volume: "
                  << theStep->GetTrack()->GetVolume()->GetName());
        EDepSimWarn("    Particle: " << particle->GetParticleName()
                 << " Depositing " << energyDeposit/MeV << " MeV");
        EDepSimWarn("    Total Energy: " 
                  << theStep->GetTrack()->GetTotalEnergy());
    }

    trackLength = std::max(trackLength,stepLength);

    EDepSimTrace("Add Step with " << energyDeposit 
              << " in " << theStep->GetTrack()->GetVolume()->GetName());

    if (energyDeposit <= 0.) {
        EDepSimWarn("EDepSim::HitSegment:: No energy deposited: " << energyDeposit);
    }

    if (trackLength <= 0.) {
        EDepSimWarn("EDepSim::HitSegment:: No track length: " << trackLength);
    }

    // Occasionally, a neutral particle will produce a particle below
    // threshold, and it will be recorded as generating the hit.  All of the
    // energy should be deposited at the stopping point of the track.
    if (stepStatus == fPostStepDoItProc
        && std::abs(particle->GetPDGCharge()) < 0.1) {
        double origStep = stepLength;
        G4ThreeVector dir = (postPos - prePos).unit();
        stepLength = trackLength = std::min(0.5*mm,0.8*origStep);
        prePos = postPos - stepLength*mm*dir;
        EDepSimDebug("EDepSim::HitSegment:: " << particle->GetParticleName()
                  << " Deposited " << energyDeposit/MeV << " MeV");
        EDepSimDebug("    Original step: " << origStep/mm << " mm");
        EDepSimDebug("    New step: " << stepLength/mm << " mm");
    }

    if (stepLength>fMaxLength || trackLength>fMaxLength) {
        G4Track* trk = theStep->GetTrack();
        EDepSimWarn("EDepSim::HitSegment:: Long step in "
                  << trk->GetVolume()->GetName());
        EDepSimWarn("  Step Length is " 
                  << stepLength/mm 
                  << " mm and track length is " 
                  << trackLength/mm << " mm");

        EDepSimWarn("  PID: " << particle->GetParticleName()
                  << " E: " << trk->GetTotalEnergy()/MeV << " MeV"
                  << " (kin: " << trk->GetKineticEnergy()/MeV << " MeV"
                  << " Deposit: " 
                  << energyDeposit/MeV << "MeV"
                  << " Status: " << theStep->GetPreStepPoint()->GetStepStatus()
                  << " -> " << theStep->GetPostStepPoint()->GetStepStatus());
        
        const G4VProcess* proc = theStep->GetPostStepPoint()
            ->GetProcessDefinedStep();
        if (!proc) {
            EDepSimWarn("    Step Limit Reached");
        }
        else {
            EDepSimWarn("    Process: " << proc->GetProcessName()
                      <<"/"<< proc->GetProcessTypeName(proc->GetProcessType()));
        }
    }

    /// First make sure the step has been initialized.
    if (!fHitVolume) {
        fHitVolume = touchable;
        fPrimaryId = FindPrimaryId(theStep->GetTrack());
        fStart.set(prePos.x(),prePos.y(),prePos.z(),
                   theStep->GetPreStepPoint()->GetGlobalTime());
        fPath.push_back(fStart.vect());
        fStop.set(postPos.x(),postPos.y(),postPos.z(),
                      theStep->GetPostStepPoint()->GetGlobalTime());
        fPath.push_back(fStop.vect());
        fContributors.push_back(theStep->GetTrack()->GetTrackID());
    }
    else {
        // Record the tracks that contribute to this hit.
        int trackId = theStep->GetTrack()->GetTrackID();
        if (trackId != fContributors.front()) fContributors.push_back(trackId);

        // Check to see if we have a new stopping point.
        if (trackId == fContributors.front()
            && (fPath.back()-prePos).mag()<0.1*mm) {
            fStop.set(postPos.x(),postPos.y(),postPos.z(),
                      theStep->GetPostStepPoint()->GetGlobalTime());
            fPath.push_back(G4ThreeVector(fStop.x(),fStop.y(),fStop.z()));
        }
    }

    fEnergyDeposit += energyDeposit;
    fSecondaryDeposit += nonIonizingDeposit;
    fTrackLength += trackLength;

    EDepSimDebug("EDepSim::HitSegment:: Deposit " << particle->GetParticleName()
              << " adds " << energyDeposit/MeV << " MeV"
              << " to " << fContributors.front()
              << " w/ " << fEnergyDeposit
              << " L " << trackLength
              << " " << fTrackLength);
}

void EDepSim::HitSegment::Draw ( void  )

virtual

Disambiguate the draw and print methods to distinguish between the G4VHit and TObject definitions.

Definition at line 284 of file EDepSimHitSegment.cc.

                                 {
    G4VVisManager* pVVisManager = G4VVisManager::GetConcreteInstance();
    if(pVVisManager) {
        G4Polyline line;
        line.push_back(G4Point3D(fStart.x(), fStart.y(), fStart.z()));
        line.push_back(G4Point3D(fStop.x(), fStop.y(), fStop.z()));
        G4Color color(1.,0.,1.);
        G4VisAttributes attribs(color);
        line.SetVisAttributes(attribs);
        pVVisManager->Draw(line);
    }
}

virtual void EDepSim::HitSegment::Draw ( const char *  )

inlinevirtual

Definition at line 58 of file EDepSimHitSegment.hh.

{}

int EDepSim::HitSegment::FindPrimaryId ( G4Track *  theTrack )

protected

Find the primary track ID for the current track. This is the primary that is the ultimate parent of the current track.

Definition at line 100 of file EDepSimHitSegment.cc.

                                                      {
    return EDepSim::TrajectoryMap::FindPrimaryId(theTrack->GetTrackID());
}

double EDepSim::HitSegment::FindSagitta ( G4Step *  theStep )

protected

Find the maximum separation (the sagitta) between the current hit segment path points, and the straight line connecting the start and proposed new stop point.

Definition at line 222 of file EDepSimHitSegment.cc.

                                                     {
    const G4ThreeVector& point = fPath.back();
    const G4ThreeVector& preStep = theStep->GetPreStepPoint()->GetPosition();

    // Make sure that the step began at the end of the current segment.  If
    // not, return a ridiculously large sagitta.
    if ((point-preStep).mag()>0.01*mm) return 10*m;

    const G4ThreeVector& postStep = theStep->GetPostStepPoint()->GetPosition();
    // The proposed new segment direction; 
    G4ThreeVector newDir = (postStep-point).unit();
    
    // Initialize the maximum sagitta found.
    double maxSagitta = 0.0;

    G4ThreeVector& front = fPath.front();

    // Loop over the existing path points and see if any would fall outside of
    // the tolerance.
    for (std::vector<G4ThreeVector>::iterator p = fPath.begin();
         p != fPath.end();
         ++p) {
        G4ThreeVector delta = ((*p)-front);
        double dist = (delta*newDir);
        maxSagitta = std::max(maxSagitta,(delta - dist*newDir).mag());
        if (maxSagitta > fMaxSagitta) break;
    }

    return maxSagitta;
}

double EDepSim::HitSegment::FindSeparation ( G4Step *  theStep )

protected

Find the maximum distance from the hit segment to the new step that is proposed to be added to the hit segment. This is used to combine secondaries with a parent track.

Definition at line 253 of file EDepSimHitSegment.cc.

                                                        {
    G4ThreeVector& front = fPath.front();
    const G4ThreeVector& back = fPath.back();
    const G4ThreeVector& preStep = theStep->GetPreStepPoint()->GetPosition();
    const G4ThreeVector& postStep = theStep->GetPostStepPoint()->GetPosition();
    G4ThreeVector dir = (back-front).unit();

    // Check to make sure the beginning of the new step isn't after the
    // end of this segment.
    if ((preStep-back)*dir>0.0) return 1000*m;

    // Check to make sure the beginning of the new step isn't before the
    // beginning of this segment.
    G4ThreeVector frontDelta = preStep-front;
    double cosDelta = frontDelta*dir;
    if (cosDelta<0.0) return 1000*m;

    // Find the distance from the segment center line to the initial point of
    // the new step.
    double s1 = (frontDelta - cosDelta*dir).mag();


    // Find the distance from the segment center line to the final point of
    // the new step.
    G4ThreeVector rearDelta = postStep-front;
    cosDelta = rearDelta*dir;
    double s2 = (rearDelta - cosDelta*dir).mag();
    
    return std::max(s1,s2);
}

int EDepSim::HitSegment::GetContributor ( int  i ) const

inline

Return a list of track identifiers that contributed to this hit. These track ids can be used as indicies to find trajectories in the TG4TrajectoryContainer object associated with an MC event.

Definition at line 71 of file EDepSimHitSegment.hh.

                                    {
        return fContributors[i];
    }

int EDepSim::HitSegment::GetContributorCount ( ) const

inline

Return a list of track identifiers that contributed to this hit. These track ids can be used as indicies to find trajectories in the TG4TrajectoryContainer object associated with an MC event.

Definition at line 78 of file EDepSimHitSegment.hh.

                                    {
        return fContributors.size();
    }

std::vector<int>& EDepSim::HitSegment::GetContributors ( )

inline

Provide public access to the contributors for internal G4 classes.

Definition at line 62 of file EDepSimHitSegment.hh.

{return fContributors;}

double EDepSim::HitSegment::GetEnergyDeposit ( void  ) const

inline

Get the total energy deposited in this hit.

Definition at line 95 of file EDepSimHitSegment.hh.

{return fEnergyDeposit;}

double EDepSim::HitSegment::GetLength ( void  ) const

virtual

Find the distance from the starting point to stoping point of the track.

Definition at line 303 of file EDepSimHitSegment.cc.

                                          {
    return (fStop.vect()- fStart.vect()).mag();
}

int EDepSim::HitSegment::GetPrimaryTrajectoryId ( void  ) const

inline

Get the TrackId of the "primary" particle that is associated with this hit. This is slightly complicated since the "interesting" primary particle is saved. For instance, if the primary particle is a pizero, The TrackId of the gamma-rays from the decay is saved. Likewise, the electron from a muon decay is used as the primary particle. You can find the "really truly" primary particle by finding the trajectory associated with this PrimaryId, and then working backwards to the associated G4PrimaryParticle (You can tell that a trajectory comes from a primary particle by checking if it's ParentID is zero. If it is zero, the trajectory came from a primary).

Definition at line 92 of file EDepSimHitSegment.hh.

{return fPrimaryId;}

double EDepSim::HitSegment::GetSecondaryDeposit ( void  ) const

inline

Get the secondary energy deposited in this hit (see the field documentation).

Definition at line 99 of file EDepSimHitSegment.hh.

{return fSecondaryDeposit;}

const G4LorentzVector& EDepSim::HitSegment::GetStart ( ) const

inline

The position of the starting point.

Definition at line 107 of file EDepSimHitSegment.hh.

{return fStart;}

const G4LorentzVector& EDepSim::HitSegment::GetStop ( ) const

inline

The position of the stopping point.

Definition at line 110 of file EDepSimHitSegment.hh.

{return fStop;}

double EDepSim::HitSegment::GetTrackLength ( void  ) const

inline

Get the total charged track length in this hit. This includes all of the contributions from secondary particles that got lumped into this hit (e.g. the contributions from delta-rays).

Definition at line 104 of file EDepSimHitSegment.hh.

{return fTrackLength;}

void EDepSim::HitSegment::ls

(

std::string

= ""

)

const

Print the hit information.

void EDepSim::HitSegment::operator delete ( void *  aHit )

inline

Definition at line 242 of file EDepSimHitSegment.hh.

                                                         {
    edepHitSegmentAllocator.FreeSingle((EDepSim::HitSegment*) aHit);
}

void * EDepSim::HitSegment::operator new ( size_t  )

inline

Definition at line 236 of file EDepSimHitSegment.hh.

                                                   {
    void *aHit;
    aHit = (void *) edepHitSegmentAllocator.MallocSingle();
    return aHit;
}

void EDepSim::HitSegment::Print ( void  )

virtual

Definition at line 297 of file EDepSimHitSegment.cc.

                                  {
    std::cout << "Hit Energy Deposit: " 
        << G4BestUnit(fEnergyDeposit,"Energy")
        << std::endl;
}

virtual void EDepSim::HitSegment::Print ( const char *  ) const

inlinevirtual

Definition at line 59 of file EDepSimHitSegment.hh.

{}

bool EDepSim::HitSegment::SameHit ( G4Step *  theStep )

virtual

Hits for the same primary particle, in the same physical volume belong in the same hit.

Definition at line 55 of file EDepSimHitSegment.cc.

                                               {
    // Check that the hit and new step are in the same volume
    G4TouchableHandle touchable 
        = theStep->GetPreStepPoint()->GetTouchableHandle();
    if (fHitVolume != touchable) {
        return false;
    }

    int trackId = theStep->GetTrack()->GetTrackID();

    // Check that the hit and new step are close together.
    double endToEnd
        = (theStep->GetPostStepPoint()->GetPosition() - fPath.front()).mag();
    if (endToEnd > fMaxLength) {
        return false;
    }

    const double epsilon = 0.01;
    double deltaT = std::abs(theStep->GetPostStepPoint()->GetGlobalTime()
                             - fStop.t());
    if (deltaT>epsilon) {
        return false;
    }

    if (fContributors.front() == trackId) {
        // This is still the same track that initially created this hit.
        // Check to see if the hit should be extended, or if we should start a
        // new segment.
        double sagitta = FindSagitta(theStep);
        if (sagitta > fMaxSagitta) {
            return false;
        }
    }
    else {
        // This is not the same track that started this hit, but check to see
        // if it is a delta-ray that should be added to this segment.
        double separation = FindSeparation(theStep);
        if (separation > fMaxSagitta) {
            return false;
        }
    }

    return true;
}

Member Data Documentation

std::vector<int> EDepSim::HitSegment::fContributors

private

The TrackID for each trajectory that contributed to this hit. This could contain the TrackID of the primary particle, but not necessarily.

Definition at line 191 of file EDepSimHitSegment.hh.

double EDepSim::HitSegment::fEnergyDeposit

private

The total energy deposit in this hit.

Definition at line 197 of file EDepSimHitSegment.hh.

EDepSim::VolumeId EDepSim::HitSegment::fHitVolume

private

The G4 physical volume that contains the hit.

Definition at line 225 of file EDepSimHitSegment.hh.

double EDepSim::HitSegment::fMaxLength

private

The maximum length between the start and stop points of the segment.

Definition at line 186 of file EDepSimHitSegment.hh.

double EDepSim::HitSegment::fMaxSagitta

private

The sagitta tolerance for the segment.

Definition at line 183 of file EDepSimHitSegment.hh.

std::vector<G4ThreeVector> EDepSim::HitSegment::fPath

private

The end points of the steps that make up this hit. This is used to make sure that the current hit stays inside of it's allowed tolerances.

Definition at line 230 of file EDepSimHitSegment.hh.

int EDepSim::HitSegment::fPrimaryId

private

The track id of the primary particle.

Definition at line 194 of file EDepSimHitSegment.hh.

double EDepSim::HitSegment::fSecondaryDeposit

private

The "secondary" energy deposit in this hit. This is used to help simulate the recombination of electrons, and is part of the total energy deposit.

DETSIM is expected to use this field to save the amount of energy deposited as opticalphotons. The remaining energy will be deposited as ionization. In this model (in argon), the mean number of quanta created will be <N_q> = (fEnergyDeposit)/(19.5*eV), N_q should be fluctuated around <N_q>, N_ph = N_q*fSecondaryDeposit/fEnergyDeposit, and N_e = N_q - N_ph. Thd fSecondaryDeposit value already includes the binomial fluctuation, so don't fluctuate N_ph or N_e.

Definition at line 210 of file EDepSimHitSegment.hh.

G4LorentzVector EDepSim::HitSegment::fStart

private

The starting position of the segment.

Definition at line 218 of file EDepSimHitSegment.hh.

G4LorentzVector EDepSim::HitSegment::fStop

private

The stopping position of the segment.

Definition at line 221 of file EDepSimHitSegment.hh.

double EDepSim::HitSegment::fTrackLength

private

The total charged track length in this hit. This includes the contribution from all of the secondary particles (e.g. delta-rays) that are included in this hit.

Definition at line 215 of file EDepSimHitSegment.hh.

---

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

• edep-sim/src/EDepSimHitSegment.hh
• edep-sim/src/EDepSimHitSegment.cc