EvtFromParent.cc

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//--------------------------------------------------------------------------
//
// Environment:
//      This software is part of the EvtGen package developed jointly
//      for the BaBar and CLEO collaborations.  If you use all or part
//      of it, please give an appropriate acknowledgement.
//
// Copyright Information: See EvtGen/COPYRIGHT
//      Copyright (C) 1998      Caltech, UCSB
//
// Module: EvtFromParent.cc
//
// Description: Routine to decay a particle according th phase space
//
// Modification history:
//
//    RYD       January 8, 1997       Module created
//
//------------------------------------------------------------------------
//
#include "EvtFromParent.hh"
#include "../EvtGenBase/EvtDecayTable.hh"
#include "../EvtGenBase/EvtGenKine.hh"
#include "../EvtGenBase/EvtGlobalSet.hh"
#include "../EvtGenBase/EvtId.hh"
#include "../EvtGenBase/EvtPDL.hh"
#include "../EvtGenBase/EvtParticle.hh"
#include "../EvtGenBase/EvtPatches.hh"
#include "../EvtGenBase/EvtReport.hh"
#include <fstream>
#include <iomanip>
#include <iostream>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
 
#include "GeneratorObject/McGenEvent.h"
#include <string>
EvtFromParent::~EvtFromParent() {}
 
void EvtFromParent::getName( std::string& model_name ) { model_name = "FromParent"; }
 
EvtDecayBase* EvtFromParent::clone() { return new EvtFromParent; }
 
void EvtFromParent::init() {
 
  // check that there are 0 arguments
  checkNArg( 0 );
}
 
void EvtFromParent::initProbMax() { noProbMax(); }
 
void EvtFromParent::decay( EvtParticle* p ) {
  bool debug = 0;
  // p->printTree();
  // std::cout<<"FromParent:p->getId() = "<<p->getId()<<std::endl;
  EvtId LambdaId = EvtPDL::getId( "Lambda0" );
  // std::cout<<"LambdaId = "<<LambdaId<<std::endl;
  EvtId antiLambdaId = EvtPDL::getId( "anti-Lambda0" );
  // std::cout<<"antiLambdaId = "<<antiLambdaId<<std::endl;
  if ( p->getId() != LambdaId && p->getId() != antiLambdaId )
  {
    std::cout << "Parent particle is required to be Lambda0 or antiLambda0" << std::endl;
    abort();
  }
  int         more      = 0;
  int         numstable = 0;
  EvtId       evtnumstable[100];
  EvtVector4R p4[20];
  /*if(EvtParticle::_NextLevelDauNum == 0) {
    report(ERROR,"EvtGen") << "EvtParticle failed to store the info of NextLevel";
  ::abort();
  }*/
  if ( EvtParticle::_NextLevelDauNum != 0 )
  {
    if ( p->getId() == LambdaId )
    {
      // pi-
      evtnumstable[numstable] = EvtPDL::evtIdFromStdHep( -211 );
      p4[numstable]           = EvtParticle::_NextLevelP4[2];
      if ( debug )
        std::cout << "FromParent: pi- p4[numstable] = " << p4[numstable] << std::endl;
      numstable++;
      // p
      evtnumstable[numstable] = EvtPDL::evtIdFromStdHep( 2212 );
      p4[numstable]           = EvtParticle::_NextLevelP4[3];
      if ( debug )
        std::cout << "FromParent: p+ p4[numstable] = " << p4[numstable] << std::endl;
      numstable++;
    }
    if ( p->getId() == antiLambdaId )
    {
      if ( debug )
        std::cout << "anti-Lambda0's parent id:" << p->getParent()->getId()
                  << " p4 =" << p->getParent()->getP4() << std::endl;
      // pi+
      evtnumstable[numstable] = EvtPDL::evtIdFromStdHep( 211 );
      p4[numstable]           = EvtParticle::_NextLevelP4[0];
      if ( debug )
        std::cout << "FromParent: pi+ p4[numstable] = " << p4[numstable] << std::endl;
      numstable++;
      // pbar
      evtnumstable[numstable] = EvtPDL::evtIdFromStdHep( -2212 );
      p4[numstable]           = EvtParticle::_NextLevelP4[1];
      if ( debug )
        std::cout << "FromParent: anti-p- p4[numstable] = " << p4[numstable] << std::endl;
      numstable++;
    }
    p->makeDaughters( numstable, evtnumstable );
    int ndaugFound = 0;
    for ( int i = 0; i < numstable; i++ )
    {
      p->getDaug( i )->init( evtnumstable[i], p4[i] );
      ndaugFound++;
    }
    if ( ndaugFound == 0 )
    {
      report( ERROR, "EvtGen" ) << "Phokhara has failed to do a decay ";
      report( ERROR, "EvtGen" ) << EvtPDL::name( p->getId() ).c_str() << " " << p->mass()
                                << endl;
      assert( 0 );
    }
    if ( p->getId() == LambdaId )
    {
      // int channel=EvtDecayTable::inChannelList(p->getId(),numstable,evtnumstable);
      // more=(channel!=-1)&&(channel!=0);
      // if(more) { std::cout<<"EvtFromParent:Existence of mode "<<channel<<" in exclusive
      // decay list has the same final state as this one"<<std::endl;abort(); }
 
      if ( debug )
        std::cout << "EvtFromParent Lambda0's parent id:" << p->getParent()->getId()
                  << " p4 =" << p->getParent()->getP4Lab() << std::endl;
      if ( debug ) std::cout << "EvtFromParent SUMMARY: part p4" << p->getP4Lab() << std::endl;
      if ( debug )
        std::cout << "EvtFromParent SUMMARY: Daug0 p4" << p->getDaug( 0 )->getP4Lab()
                  << std::endl;
      if ( debug )
        std::cout << "EvtFromParent SUMMARY: Daug1 p4" << p->getDaug( 1 )->getP4Lab()
                  << std::endl;
    }
    if ( p->getId() == antiLambdaId )
    {
      // int channel=EvtDecayTable::inChannelList(p->getId(),numstable,evtnumstable);
      // more=(channel!=0);
      // if(more) { std::cout<<"EvtFromParent:Existence of mode "<<channel<<" in exclusive
      // decay list has the same final state as this one"<<std::endl;abort(); }
 
      if ( debug )
        std::cout << "EvtFromParent antiLambda0's parent id:" << p->getParent()->getId()
                  << " p4 =" << p->getParent()->getP4Lab() << std::endl;
      if ( debug ) std::cout << "EvtFromParent SUMMARY: part p4" << p->getP4Lab() << std::endl;
      if ( debug )
        std::cout << "EvtFromParent SUMMARY: Daug0 p4" << p->getDaug( 0 )->getP4Lab()
                  << std::endl;
      if ( debug )
        std::cout << "EvtFromParent SUMMARY: Daug1 p4" << p->getDaug( 1 )->getP4Lab()
                  << std::endl;
    }
  }
  return;
}