MuonG4R4::MmSensitiveDetector Class Reference

#include <MmSensitiveDetector.h>

Inheritance diagram for MuonG4R4::MmSensitiveDetector:

Collaboration diagram for MuonG4R4::MmSensitiveDetector:

Public Member Functions
	~MmSensitiveDetector ()=default
virtual G4bool	ProcessHits (G4Step *aStep, G4TouchableHistory *ROhist) override final
	member functions
	MuonSensitiveDetector (const std::string &name, const std::string &output_key, const std::string &trf_storeKey, const MuonGMR4::MuonDetectorManager *detMgr)
	Constructor.
virtual void	Initialize (G4HCofThisEvent *HCE) override final
	Create the output container at the beginning of the event.
bool	msgLvl (const MSG::Level lvl) const
	Test the output level.
MsgStream &	msg () const
	The standard message stream.
MsgStream &	msg (const MSG::Level lvl) const
	The standard message stream.
void	setLevel (MSG::Level lvl)
	Change the current logging level.

Protected Member Functions
bool	processStep (const G4Step *step) const
	Checks whether the current step shall be processed at all.
ActsTrk::GeometryContext	getGeoContext () const
	Returns the current geometry context in the event.
xAOD::MuonSimHit *	lastSnapShot (const Identifier &gasGapId, const G4Step *hitStep)
	Returns the last snap shot of the traversing particle.
xAOD::MuonSimHit *	propagateAndSaveStrip (const Identifier &hitId, const Amg::Transform3D &toGasGap, const G4Step *hitStep)
xAOD::MuonSimHit *	saveHit (const Identifier &hitId, const Amg::Vector3D &hitPos, const Amg::Vector3D &hitDir, const double globTime, const G4Step *hitStep)
	Saves the current Step as a xAOD::MuonSimHit snapshot.

Protected Attributes
const MuonGMR4::MuonDetectorManager *	m_detMgr {nullptr}
	Pointer to the underlying detector manager.

Private Member Functions
const MuonGMR4::MmReadoutElement *	getReadoutElement (const ActsTrk::GeometryContext &gctx, const G4TouchableHistory *touchHist) const
	Retrieves the matching readout element to a G4 hit.
Identifier	getIdentifier (const ActsTrk::GeometryContext &gctx, const MuonGMR4::MmReadoutElement *readOutEle, const Amg::Vector3D &hitAtGapPlane) const
	Identify the gasGap layer of the hit.
void	initMessaging () const
	Initialize our message level and MessageSvc.

Private Attributes
SG::WriteHandle< xAOD::MuonSimHitContainer >	m_writeHandle
SG::ReadHandleKey< ActsTrk::DetectorAlignStore >	m_trfCacheKey
	ReadHandleKey to the DetectorAlignmentStore caching the relevant transformations needed in this event.
std::string	m_nm
	Message source name.
boost::thread_specific_ptr< MsgStream >	m_msg_tls
	MsgStream instance (a std::cout like with print-out levels)
std::atomic< IMessageSvc * >	m_imsg { nullptr }
	MessageSvc pointer.
std::atomic< MSG::Level >	m_lvl { MSG::NIL }
	Current logging level.
std::atomic_flag m_initialized	ATLAS_THREAD_SAFE = ATOMIC_FLAG_INIT
	Messaging initialized (initMessaging)

Detailed Description

Definition at line 29 of file MmSensitiveDetector.h.

Constructor & Destructor Documentation

~MmSensitiveDetector()

MuonG4R4::MmSensitiveDetector::~MmSensitiveDetector ( )

default

Member Function Documentation

getGeoContext()

ActsTrk::GeometryContext MuonG4R4::MuonSensitiveDetector::getGeoContext ( ) const

protectedinherited

Returns the current geometry context in the event.

Definition at line 48 of file MuonSensitiveDetector.cxx.

                                                                      {
        ActsTrk::GeometryContext gctx{};
        SG::ReadHandle trfStoreHandle{m_trfCacheKey};
        if (!trfStoreHandle.isValid()) {
            THROW_EXCEPTION("Failed to retrieve "<<m_trfCacheKey.fullKey()<<".");
        }
        gctx.setStore(std::make_unique<DetectorAlignStore>(*trfStoreHandle));
        return gctx;
    }

getIdentifier()

Identifier MmSensitiveDetector::getIdentifier ( const ActsTrk::GeometryContext & gctx, const MuonGMR4::MmReadoutElement * readOutEle, const Amg::Vector3D & hitAtGapPlane ) const

private

Identify the gasGap layer of the hit.

that's the poor man's solution to find out in which gas gap we're

Definition at line 57 of file MmSensitiveDetector.cxx.

                                                                                      {
  for (unsigned int gap = 1; gap <= readOutEle->nGasGaps(); ++gap){
     const Amg::Vector3D gapCentre = readOutEle->center(gctx, MmReadoutElement::createHash(gap, 0));
     ATH_MSG_VERBOSE("Try to match "<<Amg::toString(hitAtGapPlane)<<" to "<<Amg::toString(gapCentre)
                  <<" in "<<m_detMgr->idHelperSvc()->toStringDetEl(readOutEle->identify())<<" dZ: "
                  <<std::abs(gapCentre.z() - hitAtGapPlane.z()));
     if (std::abs(gapCentre.z() - hitAtGapPlane.z()) < tolerance) {
         ATH_MSG_VERBOSE("Assign hit "<<Amg::toString(hitAtGapPlane)<<" to "
                        <<m_detMgr->idHelperSvc()->toStringDetEl(readOutEle->identify())<<" gasGap: "<<gap);
         return readOutEle->measurementId(MmReadoutElement::createHash(gap, 1));
     }
  }
  THROW_EXCEPTION("Invalid gasgap matching for hit "<<Amg::toString(hitAtGapPlane)<<" and detector element "
                  <<m_detMgr->idHelperSvc()->toStringDetEl(readOutEle->identify()));
  return Identifier{};
}

getReadoutElement()

const MuonGMR4::MmReadoutElement * MmSensitiveDetector::getReadoutElement ( const ActsTrk::GeometryContext & gctx, const G4TouchableHistory * touchHist ) const

private

Retrieves the matching readout element to a G4 hit.

The fourth volume is the envelope volume of the NSW station. It will tell us the sector and station eta

av_4375_impr_1_MuonR4::NSW_SM2_StationMuonStation_pv_9_NSW_SM2_Station_-2_1

Find the Detector element from the Identifier

retrieve the translation of the transformation going into the current current gasVolume

Let's use the position of the first gasGap in the second quad as a reference. If the absolute z value is smaller than its z value the hit must be located in quad number one

Definition at line 76 of file MmSensitiveDetector.cxx.

                                                                                                                    {
   const std::string& stationVolume = touchHist->GetVolume(4)->GetName();
   const std::vector<std::string> volumeTokens = tokenize(stationVolume.substr(stationVolume.rfind("NSW") + 4), "_");
   ATH_MSG_VERBOSE("Name of the station volume is "<<volumeTokens);
   if (volumeTokens.size() != 4) {
      THROW_EXCEPTION(" Cannot deduce the station name from "<<stationVolume);
   }
   const std::string stName = volumeTokens[0][0] == 'S' ? "MMS" : "MML";
   const int stationEta = atoi(volumeTokens[2]);
   const int stationPhi = atoi(volumeTokens[3]);
 
   const MmIdHelper& idHelper{m_detMgr->idHelperSvc()->mmIdHelper()};
   const Identifier detElIdMl1 = idHelper.channelID(idHelper.stationNameIndex(stName), stationEta, stationPhi, 1, 1, 1);
   const Identifier detElIdMl2 = idHelper.multilayerID(detElIdMl1, 2);
   const MmReadoutElement* readOutElemMl1 = m_detMgr->getMmReadoutElement(detElIdMl1);
   const MmReadoutElement* readOutElemMl2 = m_detMgr->getMmReadoutElement(detElIdMl2);
   if (!readOutElemMl1 || !readOutElemMl2) {
      THROW_EXCEPTION(" Failed to retrieve a valid detector element from "
                    <<m_detMgr->idHelperSvc()->toStringDetEl(detElIdMl1)<<" "<<stationVolume);    
   }
   const Amg::Vector3D transformCenter = getTransform(touchHist, 0).translation();
   const Amg::Vector3D centerMl2 = readOutElemMl2->center(gctx, detElIdMl2);
   ATH_MSG_VERBOSE("Local gap position "<<Amg::toString(centerMl2)<<" transform center "<<Amg::toString(transformCenter));
   return std::abs(centerMl2.z())  - tolerance <= std::abs(transformCenter.z()) ? readOutElemMl2 : readOutElemMl1;
}

Initialize()

void MuonG4R4::MuonSensitiveDetector::Initialize ( G4HCofThisEvent * HCE )

finaloverridevirtualinherited

Create the output container at the beginning of the event.

Definition at line 37 of file MuonSensitiveDetector.cxx.

                                                           {
        if (m_writeHandle.isValid()) {
            ATH_MSG_VERBOSE("Simulation hit container "<<m_writeHandle.fullKey()<<" is already written");
            return;
        }
        if (!m_writeHandle.recordNonConst(std::make_unique<xAOD::MuonSimHitContainer>(),
                                          std::make_unique<xAOD::MuonSimHitAuxContainer>()).isSuccess()) {
            THROW_EXCEPTION(" Failed to record "<<m_writeHandle.fullKey());     
        }
        ATH_MSG_DEBUG("Output container "<<m_writeHandle.fullKey()<<" has been successfully created");
    }

initMessaging()

void AthMessaging::initMessaging ( ) const

privateinherited

Initialize our message level and MessageSvc.

This method should only be called once.

Definition at line 39 of file AthMessaging.cxx.

{
  m_imsg = Athena::getMessageSvc();
  // If user did not set an explicit level, set a default
  if (m_lvl == MSG::NIL) {
    m_lvl = m_imsg ?
      static_cast<MSG::Level>( m_imsg.load()->outputLevel(m_nm) ) :
      MSG::INFO;
  }
}

lastSnapShot()

xAOD::MuonSimHit * MuonG4R4::MuonSensitiveDetector::lastSnapShot ( const Identifier & gasGapId, const G4Step * hitStep )

protectedinherited

Returns the last snap shot of the traversing particle.

The G4 track must have stepped through the same volume. Otherwise, a nullptr is returned

Parameters

gasGapId	Identifier of the gasGap to consider
hitStep	Pointer to the current step

There's only a snapshot if the last saved hit has the same Identifier & the same particle Link + G4Track Id

Definition at line 146 of file MuonSensitiveDetector.cxx.

                                                                                 {
        TrackHelper trkHelper{hitStep->GetTrack()};
        if (m_writeHandle->empty() || 
            m_writeHandle->back()->identify() != hitId ||
            trkHelper.GenerateParticleLink() != m_writeHandle->back()->genParticleLink() ||
            dec_G4TrkId(*m_writeHandle->back()) != hitStep->GetTrack()->GetTrackID()) {
            return nullptr;
        }
        return m_writeHandle->back();
    }

msg() [1/2]

MsgStream & AthMessaging::msg ( ) const

inlineinherited

The standard message stream.

Returns a reference to the default message stream May not be invoked before sysInitialize() has been invoked.

Definition at line 163 of file AthMessaging.h.

{
  MsgStream* ms = m_msg_tls.get();
  if (!ms) {
    if (!m_initialized.test_and_set()) initMessaging();
    ms = new MsgStream(m_imsg,m_nm);
    m_msg_tls.reset( ms );
  }
 
  ms->setLevel (m_lvl);
  return *ms;
}

msg() [2/2]

MsgStream & AthMessaging::msg ( const MSG::Level lvl ) const

inlineinherited

The standard message stream.

Returns a reference to the default message stream May not be invoked before sysInitialize() has been invoked.

Definition at line 178 of file AthMessaging.h.

{ return msg() << lvl; }

msgLvl()

bool AthMessaging::msgLvl ( const MSG::Level lvl ) const

inlineinherited

Test the output level.

Parameters

lvl	The message level to test against

Returns

boolean Indicating if messages at given level will be printed

Return values

true	Messages at level "lvl" will be printed

Definition at line 151 of file AthMessaging.h.

{
  if (m_lvl <= lvl) {
    msg() << lvl;
    return true;
  } else {
    return false;
  }
}

MuonSensitiveDetector()

MuonG4R4::MuonSensitiveDetector::MuonSensitiveDetector	(	const std::string &	name,
		const std::string &	output_key,
		const std::string &	trf_storeKey,
		const MuonGMR4::MuonDetectorManager *	detMgr )

Constructor.

Parameters

name	Name of the Sensitive detctor / AthMessaging module
output_key	Key under which the sim hits are written into store gate
trf_storeKey	Location of the DetctorAlignmentStore holding the transformations per event
detMgr	Pointer to the run-4 detector manager

Definition at line 29 of file MuonSensitiveDetector.cxx.

                                                                                           :
        G4VSensitiveDetector{name},
        AthMessaging{name},
        m_writeHandle{output_key},
        m_trfCacheKey{trfStore_key},
        m_detMgr{detMgr} {
        m_trfCacheKey.initialize().ignore();
    }

ProcessHits()

G4bool MmSensitiveDetector::ProcessHits ( G4Step * aStep, G4TouchableHistory * ROhist )

finaloverridevirtual

member functions

Fetch the local -> global transformation

Definition at line 32 of file MmSensitiveDetector.cxx.

                                                                         {
 
  if (!processStep(aStep)) {
    return true;
  }
  const ActsTrk::GeometryContext gctx{getGeoContext()};
 
  const G4TouchableHistory* touchHist = static_cast<const G4TouchableHistory*>(aStep->GetPreStepPoint()->GetTouchable());
  const MuonGMR4::MmReadoutElement* readOutEle = getReadoutElement(gctx, touchHist);
 
  const Amg::Transform3D localToGlobal = getTransform(touchHist, 0);
  ATH_MSG_VERBOSE(" Track is inside volume "<< touchHist->GetHistory()->GetTopVolume()->GetName()
                 <<" transformation: "<<Amg::toString(localToGlobal));
 
  const Identifier hitID = getIdentifier(gctx, readOutEle, localToGlobal.translation());
  if (!hitID.is_valid()) {
      ATH_MSG_VERBOSE("No valid hit found");
      return true;
  }
  const Amg::Transform3D toGasGap{readOutEle->globalToLocalTrans(gctx, hitID)};
  propagateAndSaveStrip(hitID, toGasGap, aStep);
  return true;
}

processStep()

bool MuonG4R4::MuonSensitiveDetector::processStep ( const G4Step * step ) const

protectedinherited

Checks whether the current step shall be processed at all.

I.e. the particle needs to be charged, there's a minimum velocity needed and the step length must not vanish

Parameters

step	G4 step to consider

Reject secondary particles

Sensitive detector is only sensitive to charged particles or Geantinos

Definition at line 57 of file MuonSensitiveDetector.cxx.

                                                                     {
        const G4Track* currentTrack = aStep->GetTrack();
        ATH_MSG_VERBOSE("Check whether step pdgId: "<<(*currentTrack)<<" will be processed.");
        constexpr double velCutOff = 10.*Gaudi::Units::micrometer / Gaudi::Units::second;
        if (aStep->GetStepLength() < std::numeric_limits<float>::epsilon() || currentTrack->GetVelocity() < velCutOff) {
            ATH_MSG_VERBOSE("Step length is too short ");
            return false;
        }
        if (currentTrack->GetDefinition()->GetPDGCharge() == 0.0) {
            ATH_MSG_VERBOSE("Particle is neutral");
            return currentTrack->GetDefinition() == G4Geantino::GeantinoDefinition() ||
                   currentTrack->GetDefinition() == G4ChargedGeantino::ChargedGeantinoDefinition();
        }
        return true;
    }

propagateAndSaveStrip()

xAOD::MuonSimHit * MuonG4R4::MuonSensitiveDetector::propagateAndSaveStrip ( const Identifier & hitId, const Amg::Transform3D & toGasGap, const G4Step * hitStep )

protectedinherited

Fetch the step end-points

Hit direction as the momentum direction

Electrons randomly work through the gas instead of drifting through the gas -> take the prestep of the first snap shop inside the gas as pre step point

Definition at line 74 of file MuonSensitiveDetector.cxx.

                                                                                        {
        
        const G4Track* currentTrack = aStep->GetTrack();
        const Amg::Vector3D locPostStep{toGasGap*Amg::Hep3VectorToEigen(aStep->GetPostStepPoint()->GetPosition())};
        Amg::Vector3D locPreStep{toGasGap*Amg::Hep3VectorToEigen(aStep->GetPreStepPoint()->GetPosition())};

        Amg::Vector3D locHitDir = toGasGap.linear() * Amg::Hep3VectorToEigen(currentTrack->GetMomentumDirection());

        xAOD::MuonSimHit* prevHit = lastSnapShot(hitID, aStep);
        if (std::abs(currentTrack->GetParticleDefinition()->GetPDGEncoding()) == 11 && prevHit) {
            locPreStep = xAOD::toEigen(prevHit->localPosition()) - 0.5* prevHit->stepLength() * 
                        xAOD::toEigen(prevHit->localDirection());
 
            locHitDir = (locPostStep - locPreStep).unit();
        }
        const Amg::Vector3D locHitPos = 0.5* (locPreStep + locPostStep);
        ATH_MSG_VERBOSE( m_detMgr->idHelperSvc()->toStringGasGap(hitID)<<" - track: "<<(*currentTrack)
                        <<", deposit: "<<aStep->GetTotalEnergyDeposit()<<", -- local coords: "
                        <<"prestep: "<<Amg::toString(locPreStep)<<",  post step: "<<Amg::toString(locPostStep) 
                        <<" mid point: "<< Amg::toString(locHitPos)<<", direction: "<<Amg::toString(locHitDir)
                        <<", deposit: "<<aStep->GetTotalEnergyDeposit());
 
        const double globalTime = currentTrack->GetGlobalTime() + locHitDir.dot(locPostStep - locHitPos) / currentTrack->GetVelocity();
  
        xAOD::MuonSimHit* newHit = saveHit(hitID, locHitPos, locHitDir, globalTime, aStep);
        if (prevHit) {
            newHit->setStepLength((locPostStep - locPreStep).mag());
        }
        return newHit;
    }

saveHit()

xAOD::MuonSimHit * MuonG4R4::MuonSensitiveDetector::saveHit ( const Identifier & hitId, const Amg::Vector3D & hitPos, const Amg::Vector3D & hitDir, const double globTime, const G4Step * hitStep )

protectedinherited

Saves the current Step as a xAOD::MuonSimHit snapshot.

Parameters

hitId	Identifier of the gasGap/ tube where the hit was deposited
hitPos	Local position of the hit expressed w.r.t gas gap coordinate system
hitDir	Local direction of the hit expressed w.r.t gas gap coordinate system
globTime	Global time of the hit
hitStep	Pointer to the step from which the hit information was derived.

Definition at line 110 of file MuonSensitiveDetector.cxx.

                                                                          {
        const G4Track* currentTrack = aStep->GetTrack();
        TrackHelper trHelper{currentTrack};
        // If Geant4 propagates the same track through the same volume just update the last hit and don't write a new one
        xAOD::MuonSimHit* hit = lastSnapShot(hitId, aStep);
        bool newHit{false};
        if (!hit) {
            hit = m_writeHandle->push_back(std::make_unique<xAOD::MuonSimHit>());
            newHit = true;
        }
        dec_G4TrkId(*hit) = currentTrack->GetTrackID();
        hit->setIdentifier(hitId); 
        hit->setLocalPosition(xAOD::toStorage(hitPos));  
        hit->setLocalDirection(xAOD::toStorage(hitDir));
        hit->setMass(currentTrack->GetDefinition()->GetPDGMass());
        hit->setGlobalTime(globTime);
        hit->setPdgId(currentTrack->GetDefinition()->GetPDGEncoding());
        hit->setEnergyDeposit(aStep->GetTotalEnergyDeposit() + (newHit ? 0. : hit->energyDeposit()));
        hit->setKineticEnergy(currentTrack->GetKineticEnergy());
        hit->setGenParticleLink(trHelper.GenerateParticleLink());
        hit->setStepLength(aStep->GetStepLength());
        
        ATH_MSG_VERBOSE("Save new hit "<<m_detMgr->idHelperSvc()->toString(hitId)
                        <<", pdgId: "<<hit->pdgId()
                        <<", "<<hit->genParticleLink()
                        <<", trackId: "<<currentTrack->GetTrackID()<<", "
                        <<", "<<hit->genParticleLink().cptr()<<std::endl
                        <<"pos: "<<Amg::toString(hitPos)<<", dir: "<<Amg::toString(hitDir)<<", time: "<<globTime
                        <<", energy: "<<hit->kineticEnergy()<<", stepLength: "<<hit->stepLength()<<", "
                        <<", deposit energy: "<<hit->energyDeposit());
        return hit;
    }

setLevel()

void AthMessaging::setLevel ( MSG::Level lvl )

inherited

Change the current logging level.

Use this rather than msg().setLevel() for proper operation with MT.

Definition at line 28 of file AthMessaging.cxx.

{
  m_lvl = lvl;
}

Member Data Documentation

ATLAS_THREAD_SAFE

std::atomic_flag m_initialized AthMessaging::ATLAS_THREAD_SAFE = ATOMIC_FLAG_INIT

mutableprivateinherited

Messaging initialized (initMessaging)

Definition at line 141 of file AthMessaging.h.

m_detMgr

const MuonGMR4::MuonDetectorManager* MuonG4R4::MuonSensitiveDetector::m_detMgr {nullptr}

protectedinherited

Pointer to the underlying detector manager.

Definition at line 81 of file MuonSensitiveDetector.h.

{nullptr};

m_imsg

std::atomic<IMessageSvc*> AthMessaging::m_imsg { nullptr }

mutableprivateinherited

MessageSvc pointer.

Definition at line 135 of file AthMessaging.h.

{ nullptr };

m_lvl

std::atomic<MSG::Level> AthMessaging::m_lvl { MSG::NIL }

mutableprivateinherited

Current logging level.

Definition at line 138 of file AthMessaging.h.

{ MSG::NIL };

m_msg_tls

boost::thread_specific_ptr<MsgStream> AthMessaging::m_msg_tls

mutableprivateinherited

MsgStream instance (a std::cout like with print-out levels)

Definition at line 132 of file AthMessaging.h.

m_nm

std::string AthMessaging::m_nm

privateinherited

Message source name.

Definition at line 129 of file AthMessaging.h.

m_trfCacheKey

SG::ReadHandleKey<ActsTrk::DetectorAlignStore> MuonG4R4::MuonSensitiveDetector::m_trfCacheKey

privateinherited

ReadHandleKey to the DetectorAlignmentStore caching the relevant transformations needed in this event.

Definition at line 45 of file MuonSensitiveDetector.h.

m_writeHandle

SG::WriteHandle<xAOD::MuonSimHitContainer> MuonG4R4::MuonSensitiveDetector::m_writeHandle

privateinherited

Definition at line 42 of file MuonSensitiveDetector.h.

---

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

• MmSensitiveDetector.h
• MmSensitiveDetector.cxx