analysis/EICTrigger/PHPy6ParticleTrigger.C

0001 #include "PHPy6GenTrigger.h"
0002 #include "PHPy6ParticleTrigger.h"
0003 #include <phool/PHCompositeNode.h>
0004 #include <phool/phool.h>
0005 #include <phool/getClass.h>
0006
0007 #include <phhepmc/PHHepMCGenEvent.h>
0008 #include <HepMC/GenEvent.h>
0009
0010 #include <cstdlib>
0011 #include <iostream>
0012 using namespace std;
0013
0014 //___________________________________________________________________________
0015 PHPy6ParticleTrigger::PHPy6ParticleTrigger(const std::string &name):
0016   PHPy6GenTrigger(name),
0017
0018   _theParticleType(0),
0019   _Q2Min(0.0),
0020
0021   _doTheParticleType(false),
0022   _doQ2Min(false)
0023 {}
0024
0025
0026 bool PHPy6ParticleTrigger::Apply( const HepMC::GenEvent* evt )
0027 {
0028
0029   if(_doQ2Min && evt->pdf_info()->scalePDF() < _Q2Min) return false;
0030   //  cout<<"EVENT"<<endl;
0031   /*
0032   for ( HepMC::GenEvent::particle_const_iterator p
0033           = evt->particles_begin(); p != evt->particles_end(); ++p ){
0034     if((*p)->status()==1) cout<<(*p)->pdg_id()<<" "<<(*p)->momentum().eta()<<" "<<sqrt(pow((*p)->momentum().px(),2) + pow((*p)->momentum().py(),2))<<endl;
0035
0036   }
0037   */
0038   if(!_doTheParticleType) return true;
0039
0040   // Loop over all particles in the event
0041   for ( HepMC::GenEvent::particle_const_iterator p
0042           = evt->particles_begin(); p != evt->particles_end(); ++p ){
0043
0044     int pi_num = 0;
0045
0046     if((*p)->pdg_id() != _theParticleType) continue;
0047
0048     //if((*p)->pdg_id() == _theParticleType) return true;
0049
0050
0051     for ( HepMC::GenVertex::particle_iterator decay
0052         = (*p)->end_vertex()->
0053         particles_begin(HepMC::children);
0054       decay != (*p)->end_vertex()->
0055         particles_end(HepMC::children);
0056       ++decay )
0057       {
0058     // check if particle decays further
0059     if(!(*decay)->end_vertex()){
0060       if(abs((*decay)->pdg_id()) == 211) pi_num++;
0061     }
0062
0063     // loop over decay if particle decays further
0064     else if((*decay)->end_vertex()){
0065
0066       //further decay loop /
0067       for ( HepMC::GenVertex::particle_iterator second_decay
0068           = (*decay)->end_vertex()->
0069           particles_begin(HepMC::children);
0070         second_decay != (*decay)->end_vertex()->
0071           particles_end(HepMC::children);
0072         ++second_decay )
0073         {
0074           if (abs((*second_decay)->pdg_id()) == 211) pi_num++;
0075
0076           if ((*second_decay)->status() != 1){
0077         for ( HepMC::GenVertex::particle_iterator third_decay
0078             = (*second_decay)->end_vertex()->
0079             particles_begin(HepMC::children);
0080               third_decay != (*second_decay)->end_vertex()->
0081             particles_end(HepMC::children);
0082               ++third_decay )
0083           {
0084             if(abs((*third_decay)->pdg_id()) == 211) pi_num++;
0085           }
0086           }
0087         }
0088     }
0089       }
0090
0091     if (pi_num == 3) return true;
0092
0093   }//pythia event for loop
0094
0095 return false;
0096
0097 }
0098
0099 void PHPy6ParticleTrigger::SetParticleType(int pid) {
0100   _theParticleType = pid;
0101   _doTheParticleType = true;
0102 }
0103
0104 void PHPy6ParticleTrigger::SetQ2Min(double Q2) {
0105   _Q2Min = Q2;
0106   _doQ2Min = true;
0107 }