G4INCLOmegaNToPiNChannel.cc

Go to the documentation of this file. Or view the newest version in sPHENIX GitHub for file G4INCLOmegaNToPiNChannel.cc

//
// ********************************************************************
// * License and Disclaimer                                           *
// *                                                                  *
// * The  Geant4 software  is  copyright of the Copyright Holders  of *
// * the Geant4 Collaboration.  It is provided  under  the terms  and *
// * conditions of the Geant4 Software License,  included in the file *
// * LICENSE and available at  http://cern.ch/geant4/license .  These *
// * include a list of copyright holders.                             *
// *                                                                  *
// * Neither the authors of this software system, nor their employing *
// * institutes,nor the agencies providing financial support for this *
// * work  make  any representation or  warranty, express or implied, *
// * regarding  this  software system or assume any liability for its *
// * use.  Please see the license in the file  LICENSE  and URL above *
// * for the full disclaimer and the limitation of liability.         *
// *                                                                  *
// * This  code  implementation is the result of  the  scientific and *
// * technical work of the GEANT4 collaboration.                      *
// * By using,  copying,  modifying or  distributing the software (or *
// * any work based  on the software)  you  agree  to acknowledge its *
// * use  in  resulting  scientific  publications,  and indicate your *
// * acceptance of all terms of the Geant4 Software license.          *
// ********************************************************************
//
// INCL++ intra-nuclear cascade model
// Alain Boudard, CEA-Saclay, France
// Joseph Cugnon, University of Liege, Belgium
// Jean-Christophe David, CEA-Saclay, France
// Pekka Kaitaniemi, CEA-Saclay, France, and Helsinki Institute of Physics, Finland
// Sylvie Leray, CEA-Saclay, France
// Davide Mancusi, CEA-Saclay, France
//
#define INCLXX_IN_GEANT4_MODE 1

#include "globals.hh"

#include "G4INCLOmegaNToPiNChannel.hh"
#include "G4INCLKinematicsUtils.hh"
#include "G4INCLBinaryCollisionAvatar.hh"
#include "G4INCLRandom.hh"
#include "G4INCLGlobals.hh"
#include "G4INCLLogger.hh"

namespace G4INCL {

    OmegaNToPiNChannel::OmegaNToPiNChannel(Particle *p1, Particle *p2)
    : particle1(p1), particle2(p2)
    {

    }

    OmegaNToPiNChannel::~OmegaNToPiNChannel(){

    }

    void OmegaNToPiNChannel::fillFinalState(FinalState *fs) {
        Particle * nucleon;
        Particle * omega;
        if(particle1->isNucleon()) {
            nucleon = particle1;
            omega = particle2;
        } else {
            nucleon = particle2;
            omega = particle1;
        }

    const G4double r2 = Random::shoot();
    if (nucleon->getType() == Neutron) {
      if (r2*3. < 2.) {
        nucleon->setType(Proton);
        omega->setType(PiMinus);
      }
      else {
        nucleon->setType(Neutron);
        omega->setType(PiZero);
      }
    }
    else {
      if (r2*3. < 2.) {
        nucleon->setType(Neutron);
        omega->setType(PiPlus);
      }
      else {
        nucleon->setType(Proton);
        omega->setType(PiZero);
      }
    }
    
        G4double sh=nucleon->getEnergy()+omega->getEnergy();
    G4double mn=nucleon->getMass();
    G4double me=omega->getMass();
    G4double en=(sh*sh+mn*mn-me*me)/(2*sh);
    nucleon->setEnergy(en);
    G4double ee=std::sqrt(en*en-mn*mn+me*me);
    omega->setEnergy(ee);
    G4double pn=std::sqrt(en*en-mn*mn);
/*// test isotropy
    const G4double pi=std::acos(-1.0);    
    G4double x1;
    G4double u1;
    G4double fteta;
    G4double teta;
    G4double fi;

    G4int passe1=0;
    while (passe1==0) {
      // Sample x from 0 to pi/2
      x1=(pi/2.)*Random::shoot();
      // Sample u from 0 to 1
      u1=Random::shoot();
      fteta=std::sin(x1);
      // The condition
      if (u1 < fteta) {
        teta=x1;
        passe1=1;
          if (Random::shoot() < 0.5) {
          teta=pi-teta;
        }
      }
      }
        fi=(2.0*pi)*Random::shoot();
    
// end test   
        ThreeVector mom_nucleon(
                                pn*std::sin(teta)*std::cos(fi),
                                pn*std::sin(teta)*std::sin(fi),
                                pn*std::cos(teta)
                                );
    if (Random::shoot() < 0.5) {
      nucleon->setMomentum(mom_nucleon);
      omega->setMomentum(-mom_nucleon);
    }
    else {
      omega->setMomentum(mom_nucleon);
        nucleon->setMomentum(-mom_nucleon);
    }
*/
    ThreeVector mom_nucleon = Random::normVector(pn);
    
    nucleon->setMomentum(mom_nucleon);
    omega->setMomentum(-mom_nucleon);
        
        fs->addModifiedParticle(nucleon);
        fs->addModifiedParticle(omega);
    }

}