DEventProcessor_DCdEdxStudy_tree.cc

Go to the documentation of this file.

#include "DEventProcessor_DCdEdxStudy_tree.h"

// The executable should define the ROOTfile global variable. It will
// be automatically linked when dlopen is called.
extern TFile *ROOTfile;

// Routine used to create our DEventProcessor
extern "C"{
void InitPlugin(JApplication *app){
   InitJANAPlugin(app);
   app->AddProcessor(new DEventProcessor_DCdEdxStudy_tree());
}
} // "C"


//------------------
// init
//------------------
jerror_t DEventProcessor_DCdEdxStudy_tree::init(void)
{

   dDCdEdxInformation = new DCdEdxInformation();
   dPluginTree_DCdEdxInformation = new TTree("dPluginTree_DCdEdxInformation", "DC dEdx Information");
   dPluginTree_DCdEdxInformation->Branch("dPluginBranch_DCdEdxInformation", "DCdEdxInformation", &dDCdEdxInformation);

   return NOERROR;
}

//------------------
// brun
//------------------
jerror_t DEventProcessor_DCdEdxStudy_tree::brun(JEventLoop *eventLoop, int32_t runnumber)
{

   return NOERROR;
}

//------------------
// evnt
//------------------
jerror_t DEventProcessor_DCdEdxStudy_tree::evnt(JEventLoop *loop, uint64_t eventnumber)
{
  // Get the particle ID algorithms
   vector<const DParticleID *> locPIDAlgorithms;
   eventLoop->Get(locPIDAlgorithms);
   if(locPIDAlgorithms.size() < 1){
      _DBG_<<"Unable to get a DParticleID object! NO PID will be done!"<<endl;
      return RESOURCE_UNAVAILABLE;
   }
   // Drop the const qualifier from the DParticleID pointer (I'm surely going to hell for this!)
   locPIDAlgorithm = const_cast<DParticleID*>(locPIDAlgorithms[0]);

   // Warn user if something happened that caused us NOT to get a locPIDAlgorithm object pointer
   if(!locPIDAlgorithm){
      _DBG_<<"Unable to get a DParticleID object! NO PID will be done!"<<endl;
      return RESOURCE_UNAVAILABLE;
   }

   vector<const DMCThrown*> locDMCThrownVector;
   const DMCThrown *locDMCThrown;
   loop->Get(locDMCThrownVector);

   vector<const DChargedTrackHypothesis*> locChargedTrackHypothesisVector;
   const DChargedTrackHypothesis *locChargedTrackHypothesis;
   loop->Get(locChargedTrackHypothesisVector);

   const DTrackTimeBased *locTrackTimeBased;

   Particle_t locThrownPID, locReconstructedPID;
   float locThrownMass, locMomentum, locBeta;

   if(locDMCThrownVector.size() != 1)
      return NOERROR; //routine assumes only one thrown track (matching not performed!)
   if(locChargedTrackHypothesisVector.size() == 0)
      return NOERROR;
   locDMCThrown = locDMCThrownVector[0];
   locThrownPID = Particle_t(locDMCThrown->type);
   locThrownMass = ParticleMass(locThrownPID);

   bool locPIDMatchFlag = false;
   for(unsigned int loc_i = 0; loc_i < locChargedTrackHypothesisVector.size(); loc_i++){
      locChargedTrackHypothesis = locChargedTrackHypothesisVector[loc_i];
      locTrackTimeBased = locChargedTrackHypothesis->dTrackTimeBased;
      locReconstructedPID = locChargedTrackHypothesis->dPID;
      if(locReconstructedPID == locThrownPID){
         locPIDMatchFlag = true;
         break;
      }
   }
   if(locPIDMatchFlag == false)
      locTrackTimeBased = locChargedTrackHypothesisVector[0]->dTrackTimeBased;

   locMomentum = locTrackTimeBased->momentum().Mag();
   locBeta = locMomentum/sqrt(locThrownMass*locThrownMass + locMomentum*locMomentum);

   // Although we are only filling objects local to this plugin, TTree::Fill() periodically writes to file: Global ROOT lock
   japp->RootWriteLock(); //ACQUIRE ROOT LOCK

   //low-momentum & beta protons are reconstructed as low-momentum but high-beta pions
   dDCdEdxInformation->dBeta = locBeta;
   dDCdEdxInformation->dMomentum = locMomentum;
   dDCdEdxInformation->dTheta = locTrackTimeBased->momentum().Theta();
   dDCdEdxInformation->dVertexZ = locTrackTimeBased->z();

   dDCdEdxInformation->ddEdx_FDC = locTrackTimeBased->ddEdx_FDC; //units of GeV/cm
   dDCdEdxInformation->ddx_FDC = locTrackTimeBased->ddx_FDC;
   dDCdEdxInformation->dNumHitsUsedFordEdx_FDC = locTrackTimeBased->dNumHitsUsedFordEdx_FDC;
   dDCdEdxInformation->ddEdx_CDC = locTrackTimeBased->ddEdx_CDC; //units of GeV/cm
   dDCdEdxInformation->ddx_CDC = locTrackTimeBased->ddx_CDC;
   dDCdEdxInformation->dNumHitsUsedFordEdx_CDC = locTrackTimeBased->dNumHitsUsedFordEdx_CDC;

   dDCdEdxInformation->dChiSq_DCdEdx = locChargedTrackHypothesis->dChiSq_DCdEdx;
   dDCdEdxInformation->dNDF_DCdEdx = locChargedTrackHypothesis->dNDF_DCdEdx;
   dDCdEdxInformation->dFOM = TMath::Prob(dDCdEdxInformation->dChiSq_DCdEdx, dDCdEdxInformation->dNDF_DCdEdx);
   dPluginTree_DCdEdxInformation->Fill();

   japp->RootUnLock(); //RELEASE ROOT LOCK

   return NOERROR;
}

//------------------
// erun
//------------------
jerror_t DEventProcessor_DCdEdxStudy_tree::erun(void)
{
   // Any final calculations on histograms (like dividing them)
   // should be done here. This may get called more than once.
   return NOERROR;
}

//------------------
// fini
//------------------
jerror_t DEventProcessor_DCdEdxStudy_tree::fini(void)
{
   return NOERROR;
}