ZDC_FiberSD Class Reference

#include <ZDC_FiberSD.h>

Inheritance diagram for ZDC_FiberSD:

Collaboration diagram for ZDC_FiberSD:

Public Member Functions
	ZDC_FiberSD (const G4String &name, const G4String &hitCollectionName, const float &readoutPos)
void	Initialize (G4HCofThisEvent *) override final
G4bool	ProcessHits (G4Step *, G4TouchableHistory *) override final

Private Member Functions
	FRIEND_TEST (ZDC_FiberSDtest, ProcessHits)
ZDC_SimFiberHitCollectionBuilder *	getHitCollection () const

Private Attributes
std::string	m_hitCollectionName
ZDC_SimFiberHitCollectionBuilder *	m_HitColl {}
float	m_readoutPos

Detailed Description

Definition at line 22 of file ZDC_FiberSD.h.

Constructor & Destructor Documentation

ZDC_FiberSD()

ZDC_FiberSD::ZDC_FiberSD	(	const G4String &	name,
		const G4String &	hitCollectionName,
		const float &	readoutPos )

Definition at line 23 of file ZDC_FiberSD.cxx.

    : G4VSensitiveDetector(name), m_hitCollectionName(hitCollectionName), m_readoutPos(readoutPos)
{
    
}

Member Function Documentation

FRIEND_TEST()

ZDC_FiberSD::FRIEND_TEST ( ZDC_FiberSDtest , ProcessHits  )

private

getHitCollection()

ZDC_SimFiberHitCollectionBuilder * ZDC_FiberSD::getHitCollection ( ) const

private

Definition at line 160 of file ZDC_FiberSD.cxx.

{
    auto* eventInfo = AtlasG4EventUserInfo::GetEventUserInfo();
    if (!eventInfo) {
        return nullptr;
    }
    auto hitCollections = eventInfo->GetHitCollectionMap();
    return hitCollections ? hitCollections->Find<ZDC_SimFiberHitCollectionBuilder>(m_hitCollectionName) : nullptr;
}

Initialize()

void ZDC_FiberSD::Initialize ( G4HCofThisEvent * )

finaloverride

Definition at line 29 of file ZDC_FiberSD.cxx.

{
    m_HitColl = getHitCollection();
}

ProcessHits()

G4bool ZDC_FiberSD::ProcessHits ( G4Step * aStep, G4TouchableHistory *  )

finaloverride

Definition at line 41 of file ZDC_FiberSD.cxx.

{
    if (!m_HitColl) {
        m_HitColl = getHitCollection();
        if (!m_HitColl) {
            return false;
        }
    }
 
    G4ThreeVector pos = aStep->GetTrack()->GetPosition();
    G4ThreeVector momentum = aStep->GetPreStepPoint()->GetMomentum();
 
    /*************************************************
    * Reject everything but optical photons
    **************************************************/
    if (aStep->GetTrack()->GetDefinition() != G4OpticalPhoton::OpticalPhotonDefinition()){
        return true;
    }
 
 
    /*************************************************
    * Reject downward going photons
    **************************************************/
    if (momentum.y() < 0.0){
        aStep->GetTrack()->SetTrackStatus(fStopAndKill);
        return true;
    }
 
 
    /*************************************************
    * Reject photons not at the boundary of two volumes
    **************************************************/
    G4StepPoint *endPoint = aStep->GetPostStepPoint();
    if (endPoint->GetStepStatus() != fGeomBoundary)
        return true;
 
    
    /*************************************************
    * Reject photons that are reflected back down 
    * from the top of the fiber
    **************************************************/
 
    // Get the refractive index
    G4MaterialPropertiesTable *MPT = aStep->GetPreStepPoint()->GetMaterial()->GetMaterialPropertiesTable();
    if (!MPT) //Safety check
        return true;
    G4MaterialPropertyVector *RindexMPV = MPT->GetProperty(kRINDEX);
    if (!RindexMPV)//Safety check
        return true;
 
    G4double Rindex;
    size_t index = 0;
    double photonEnergy = aStep->GetTrack()->GetDynamicParticle()->GetTotalMomentum();
    Rindex = RindexMPV->Value(photonEnergy, index);
 
    //Determine the photon's angle from the vertical axis
    G4ThreeVector momDir = aStep->GetPreStepPoint()->GetMomentumDirection();
    G4double angleFromY = atan(sqrt(1 - pow(momDir.y(), 2.0)) / momDir.y());
 
    // kill the photon if angle is greater than TIR critical angle
    // We're assuming the fiber's top face's normal vector is parallel to the y axis
    if (angleFromY > asin(1.0 / Rindex)){ 
        aStep->GetTrack()->SetTrackStatus(fStopAndKill);
        return true;
    }
 
    /*************************************************
    * Reject photons that are not totally internally 
    * reflected inside the fiber
    **************************************************/
 
    G4bool isTIR = false;
    G4ProcessVector *postStepDoItVector = G4OpticalPhoton::OpticalPhotonDefinition()->GetProcessManager()->GetPostStepProcessVector(typeDoIt);
    G4int n_proc = postStepDoItVector->entries();
    for (G4int i = 0; i < n_proc; ++i){
        G4OpBoundaryProcess *opProc = dynamic_cast<G4OpBoundaryProcess *>((*postStepDoItVector)[i]);
        if (opProc && opProc->GetStatus() == TotalInternalReflection){
            isTIR = true;
            break;
        }
    }
 
    if(!isTIR){ 
        aStep->GetTrack()->SetTrackStatus(fStopAndKill);
        return true;
    }
 
    /*************************************************
    * Simulate absorption by calculating the photon's
    * remaining path length and rolling a random number
    * against its absorption chance
    **************************************************/
    G4MaterialPropertyVector *AbsMPV = MPT->GetProperty(kABSLENGTH);
    G4double Absorption = AbsMPV->Value(aStep->GetTrack()->GetDynamicParticle()->GetTotalMomentum(), index);
 
    G4double pathLength = (m_readoutPos - pos.y()) / cos(angleFromY);
    G4double absChance = 1 - exp(-pathLength / Absorption);
 
    // This check amounts to if(absorbed)
    if (CLHEP::RandFlat::shoot(0.0, 1.0) < absChance){
        aStep->GetTrack()->SetTrackStatus(fStopAndKill);
        return true;
    }
 
    /*************************************************
    * Record the survivors
    **************************************************/
 
    Identifier id;
    id = aStep->GetPreStepPoint()->GetPhysicalVolume()->GetCopyNo();
    m_HitColl->AddHit(id, photonEnergy);
 
    /*************************************************
    * Put the survivors out of their misery
    **************************************************/
    aStep->GetTrack()->SetTrackStatus(fStopAndKill);
    return true;
}

Member Data Documentation

m_HitColl

ZDC_SimFiberHitCollectionBuilder* ZDC_FiberSD::m_HitColl {}

private

Definition at line 39 of file ZDC_FiberSD.h.

{};

m_hitCollectionName

std::string ZDC_FiberSD::m_hitCollectionName

private

Definition at line 37 of file ZDC_FiberSD.h.

m_readoutPos

float ZDC_FiberSD::m_readoutPos

private

Definition at line 40 of file ZDC_FiberSD.h.

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

• ZDC_FiberSD.h
• ZDC_FiberSD.cxx