HepMCInterface_common.hh

Go to the documentation of this file.

 
#pragma once
 
#include "HEJ/Event.hh"
#include "HEJ/Particle.hh"
 
namespace HEJ {
  namespace detail_HepMC {
 
    template<class FourVector>
    FourVector to_FourVector(Particle const & sp){
      return {sp.px(), sp.py(), sp.pz(), sp.E()};
    }
    namespace status_codes {
      enum Status: unsigned {
        out = 1,    
        decay = 2,  
        beam = 4,   
        in = 11,    
      };
    }
    using Status = status_codes::Status;
 
    template<int V> struct HepMCVersion;
    template<int V>
    using GenEvent = typename HepMCVersion<V>::GenEvent;
    template<int V>
    using Beam = typename HepMCVersion<V>::Beam;
 
    template<int V>
    auto make_particle_ptr(
        Particle const & sp, int status
    );
 
    template<int V>
    auto make_vx_ptr();
 
    template<int V>
    GenEvent<V> HepMC_init_kinematics(
        Event const & event, Beam<V> const & beam, GenEvent<V> && out_ev
    ){
      out_ev.set_beam_particles(beam[0], beam[1]);
 
      auto vx = make_vx_ptr<V>();
      for(size_t i=0; i<event.incoming().size(); ++i){
        auto particle = make_particle_ptr<V>(event.incoming()[i], Status::in);
        auto vx_beam = make_vx_ptr<V>();
        vx_beam->add_particle_in(beam[i]);
        vx_beam->add_particle_out(particle);
        out_ev.add_vertex(vx_beam);
        vx->add_particle_in(particle);
      }
      for(size_t i=0; i < event.outgoing().size(); ++i){
        auto const & out = event.outgoing()[i];
        auto particle = make_particle_ptr<V>(out, Status::out);
        const int status = event.decays().count(i)?Status::decay:Status::out;
        particle->set_status(status);
        if( status == Status::decay ){
          auto vx_decay = make_vx_ptr<V>();
          vx_decay->add_particle_in(particle);
          for( auto const & decay: event.decays().at(i) ){
            vx_decay->add_particle_out(
                make_particle_ptr<V>(decay, Status::out)
            );
          }
          out_ev.add_vertex(vx_decay);
        }
        vx->add_particle_out(particle);
      }
      out_ev.add_vertex(vx);
 
      return out_ev;
    }
  } // namespace detail_HepMC
} // namespace HEJ