EvtPHOTOS.hh

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#ifdef EVTGEN_PHOTOS
#ifndef EVTPHOTOS_HH
#define EVTPHOTOS_HH
 
#include "EvtGenBase/EvtAbsRadCorr.hh"
#include "EvtGenBase/EvtHepMCEvent.hh"
#include "EvtGenBase/EvtId.hh"
#include "EvtGenBase/EvtParticle.hh"
#include "EvtGenBase/EvtVector4R.hh"
 
#ifdef EVTGEN_HEPMC3
#include "HepMC3/Units.h"
 
#include "Photos/PhotosHepMC3Event.h"
#include "Photos/PhotosHepMC3Particle.h"
#else
#include "Photos/PhotosHepMCEvent.h"
#include "Photos/PhotosHepMCParticle.h"
#include "Photos/PhotosParticle.h"
#endif
 
#include <mutex>
#include <string>
 
class EvtParticle;
class EvtAbsExternalGen;
 
/*
 * Description: EvtGen's interface to PHOTOS for generation of
 *              QED final-state radiation.
 */
 
class EvtPHOTOS : public EvtAbsRadCorr {
  public:
    EvtPHOTOS( const std::string& photonType = "gamma",
               const bool useEvtGenRandom = true,
               const double infraredCutOff = 1.0e-7,
               const double maxWtInterference = 64.0 );
 
    void initialise() override;
 
    void doRadCorr( EvtParticle* theParticle ) override;
 
  private:
    GenParticlePtr createGenParticle( const EvtParticle& theParticle,
                                      bool incoming ) const;
 
    int getNumberOfPhotons( const GenVertexPtr theVertex ) const;
 
    // Use EvtGen's random number generator
    bool m_useEvtGenRandom = true;
 
    // Default settings for PHOTOS
    // Minimum photon Energy (infrared cut-off).
    double m_infraredCutOff = 1.0e-7;
    // Maximum value of the interference weight
    double m_maxWtInterference = 64.0;
 
    // Default photon type, id, pdg number and mass
    std::string m_photonType = "gamma";
    EvtId m_gammaId = EvtId( -1, -1 );
    long int m_gammaPDG = 22;
 
    static bool m_initialised;
    static std::mutex m_photos_mutex;
};
 
#endif
 
#endif