loon: PhotonCompositeGreenTracker Class Reference

Constructor & Destructor Documentation

PhotonCompositeGreenTracker::PhotonCompositeGreenTracker

(

)

Definition at line 18 of file PhotonCompositeGreenTracker.cxx.

00019 {
00020   Configure(PhotonConfiguration()); // Set up default values.
00021 }

Member Function Documentation

PhotonCompositeGreenTracker::ClassDef	(	PhotonCompositeGreenTracker	,
		0
	)	`[private]`

void PhotonCompositeGreenTracker::Configure ( const Registry & r ) [virtual]

Reimplemented from PhotonTransportModule.

Definition at line 26 of file PhotonCompositeGreenTracker.cxx.

References fClearFibreAttenLength1, fClearFibreAttenLength2, fClearFibreAttenN1, fClearFibreAttenN2, fClearFibreIndex, fFibreAttenLength1, fFibreAttenLength2, fFibreAttenN1, fFibreAttenN2, fFibreIndex, fQuantumEfficiency, fReflectorFibreReflec, Registry::Get(), MSG, and PhotonTransportModule::SetGreenPrescaleFactor().

00027 {
00028   // The other classses in the model need configuring:
00029   MSG("Photon",Msg::kDebug) << "Configuring CompositeGreenTracker." << std::endl;
00030 
00031   double tmpd;
00032   if (r.Get("FibreIndex",tmpd))           fFibreIndex  = tmpd;
00033   if (r.Get("ClearFibreIndex",tmpd))      fClearFibreIndex  = tmpd;
00034 
00035   if (r.Get("ReflectorFibreReflec",tmpd)) fReflectorFibreReflec  = tmpd;
00036   if (r.Get("QuantumEfficiency",tmpd))    fQuantumEfficiency = tmpd;
00037   if (r.Get("FibreAttenN1",tmpd))        fFibreAttenN1 = tmpd;
00038   if (r.Get("FibreAttenN2",tmpd))        fFibreAttenN2 = tmpd;
00039   if (r.Get("FibreAttenLength1",tmpd))   fFibreAttenLength1 = tmpd;
00040   if (r.Get("FibreAttenLength2",tmpd))   fFibreAttenLength2 = tmpd;
00041   if (r.Get("ClearFibreAttenN1",tmpd))   fClearFibreAttenN1 = tmpd;
00042   if (r.Get("ClearFibreAttenN2",tmpd))   fClearFibreAttenN2 = tmpd;
00043   if (r.Get("ClearFibreAttenLength1",tmpd)) fClearFibreAttenLength1 = tmpd;
00044   if (r.Get("ClearFibreAttenLength2",tmpd)) fClearFibreAttenLength2 = tmpd ;
00045   // Set the prescale factors.
00046   SetGreenPrescaleFactor(fQuantumEfficiency); // Phototube photocathode acceptance.
00047 }

Bool_t PhotonCompositeGreenTracker::GreenPhotonToPe	(	const UgliStripHandle &	inStrip,
		DigiPhoton *	inGreenPhoton,
		DigiPE *&	outPe,
		StripEnd::StripEnd_t &	outEnd
	)	`[virtual]`

Reimplemented from PhotonTransportModule.

Definition at line 57 of file PhotonCompositeGreenTracker.cxx.

References UgliStripHandle::ClearFiber(), Calibrator::DecalAttenCorrected(), PhotonUtil::DoubleExp(), fClearFibreAttenLength1, fClearFibreAttenLength2, fClearFibreAttenN1, fClearFibreAttenN2, fClearFibreIndex, fFibreIndex, DigiPhoton::GetCosX(), UgliStripHandle::GetHalfLength(), PlexHandle::GetPixelSpotId(), UgliStripHandle::GetSEId(), Calibrator::Instance(), UgliStripHandle::IsMirrored(), DigiPhoton::ParentHit(), UgliStripHandle::PartialLength(), PlexStripEndId::SetEnd(), DigiPhoton::T(), UgliStripHandle::WlsBypass(), UgliStripHandle::WlsPigtail(), and DigiPhoton::X().

00061 {
00062   outPe = NULL;
00063   if(!inGreenPhoton) return false;
00064 
00065   // First, figure out which way we're going.
00066   StripEnd::StripEnd_t dir = 
00067     (inGreenPhoton->GetCosX()>0) ? StripEnd::kPositive : StripEnd::kNegative;
00068 
00069   StripEnd::StripEnd_t readout = dir; // Assume we're reading out the end it's going.
00070 
00071   // Is the end we've gotten to mirrored? 
00072   if(inStrip.IsMirrored(dir)) {
00073     // Ok, then we're going to need to flip it.
00074     // Does this photon survive the flip?
00075     if(fRandom->Rndm() > fReflectorFibreReflec) {
00076       return false;
00077     }
00078 
00079     // We survived the reflection.
00080     readout = (dir==StripEnd::kPositive) ? StripEnd::kNegative : StripEnd::kPositive;
00081   }
00082 
00083   // Find the distance down the clear strip.
00084   // Note that this distance is used only for attenuation, not for propagation time.
00085   Double_t clearDist = inStrip.ClearFiber(readout);
00086 
00087   // See if it survives the readout cable. 
00088   Double_t clearProb = PhotonUtil::DoubleExp(clearDist, 
00089                                              fClearFibreAttenN1,      fClearFibreAttenN2,
00090                                              fClearFibreAttenLength1, fClearFibreAttenLength2,
00091                                              true);
00092   if(fRandom->Rndm() > clearProb) return false;
00093    
00094   
00095   // The photon is reflecting it's way down the strip.
00096   // Figure out how far it has to go in each medium.
00097 
00098   double distToCenter = (inGreenPhoton->GetCosX()>0) ? (-inGreenPhoton->X())
00099     : (inGreenPhoton->X());
00100 
00101   Double_t halfgreen = inStrip.GetHalfLength()         // Distance to end of strip;
00102                       +inStrip.WlsPigtail(readout); // Pigtail on readout end.
00103 
00104 
00105   Double_t greenDist = distToCenter // Distance to center of strip.
00106                      + halfgreen;
00107 
00108 
00109   // Deal with WLS bypass, if any
00110   double bypassExtra = 0;
00111   if(inStrip.WlsBypass() >0) {    
00112     bypassExtra = ( inStrip.PartialLength(StripEnd::kNegative) + 
00113                     inStrip.PartialLength(StripEnd::kPositive) +
00114                     inStrip.WlsBypass() - 
00115                     inStrip.GetHalfLength()*2.0 );
00116 
00117     // place in the middle of the break;
00118     float x_break =0.5* (inStrip.PartialLength(StripEnd::kNegative) 
00119                          - inStrip.PartialLength(StripEnd::kPositive) );
00120 
00121     if(inGreenPhoton->X() < x_break) {
00122       // If the photon is at -ve end and going +ve, it goes through the bypass
00123       if(dir==StripEnd::kPositive)  greenDist+= bypassExtra;
00124     } else {
00125       // If the photon is at +ve end and going -ve, it goes through the bypass
00126       if(dir==StripEnd::kNegative)  greenDist+= bypassExtra;
00127     }
00128   }
00129 
00130   if(readout!=dir) {
00131     // i.e. we're going towards the mirror end but being read out on the non-mirror end
00132     greenDist+= inStrip.GetHalfLength()*2.0; // Gotta double back...
00133     greenDist+= bypassExtra;                 // ... through the ENTIRE green fibre
00134     greenDist+= inStrip.WlsPigtail(dir)*2.0; // And we have to go through the pigtail, if any
00135                                              // (N.B. This is for caldet, which has pigtails before the reflector)
00136   }
00137 
00138 
00139   // See if it survives the green fibre:
00140   double gdir = 1.0;
00141   if(readout == StripEnd::kNegative) gdir = -1.0;
00142   Calibrator& Cal = Calibrator::Instance();
00143   PlexStripEndId seid = inStrip.GetSEId();
00144   seid.SetEnd(readout);
00145 
00146   double greenProb =1.0-
00147     (  Cal.DecalAttenCorrected(1.0, inGreenPhoton->X(), seid) 
00148      / Cal.DecalAttenCorrected(1.0, gdir*halfgreen,     seid) );
00149 
00150   //MSG("mydebug",Msg::kInfo) << "Green survival prob: " << greenProb << endl;
00151 
00152   if(fRandom->Rndm() < greenProb) return false;
00153 
00154   // But... we don't travel in a straight line!
00155   // We bounce around the fibre a lot. This makes the path length longer.
00156   double greenBouncedDist = greenDist/ fabs(inGreenPhoton->GetCosX());
00157   double clearBouncedDist = clearDist/ fabs(inGreenPhoton->GetCosX());
00158   
00159   // ASSUME: no loss at connector interfaces
00160 
00161   // PMT: ASSUME:
00162   // FIXME: Assume 100% quantum efficiency, or efficiency dealt with
00163   // in photon computation.
00164 
00165   // Build the resultant digipe.
00166   // Find the time of arrival.
00167   double time = inGreenPhoton->T()
00168     + greenBouncedDist * fFibreIndex / Munits::c_light
00169     + clearBouncedDist * fClearFibreIndex / Munits::c_light;
00170 
00171   PlexHandle plex(fContext);
00172   PlexPixelSpotId psid = plex.GetPixelSpotId(seid);
00173 
00174   outPe = new DigiPE( time, psid, inGreenPhoton->ParentHit() );
00175   outEnd = readout;
00176 
00177   return true;  
00178 }

Member Data Documentation

Generated on Mon Feb 15 11:10:01 2010 for loon by

1.3.9.1

PhotonCompositeGreenTracker Class Reference

Public Member Functions

Private Member Functions

Private Attributes

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation


Public Member Functions
	PhotonCompositeGreenTracker ()
virtual void	Configure (const Registry &r)
virtual Bool_t	GreenPhotonToPe (const UgliStripHandle &inStrip, DigiPhoton inGreenPhoton, DigiPE &outPe, StripEnd::StripEnd_t &outEnd)
Private Member Functions
	ClassDef (PhotonCompositeGreenTracker, 0)
Private Attributes
Double_t	fFibreIndex
Double_t	fClearFibreIndex
Double_t	fReflectorFibreReflec
Double_t	fQuantumEfficiency
Double_t	fFibreAttenN1
Double_t	fFibreAttenN2
Double_t	fFibreAttenLength1
Double_t	fFibreAttenLength2
Double_t	fClearFibreAttenN1
Double_t	fClearFibreAttenN2
Double_t	fClearFibreAttenLength1
Double_t	fClearFibreAttenLength2
Double_t	fDarkNoiseRate
Double_t	fGreenNoiseRate
Double_t	fNoiseWindow