Rivet analyses

// -*- C++ -*-
#include "Rivet/Analysis.hh"
#include "Rivet/Projections/Beam.hh"
#include "Rivet/Projections/Thrust.hh"
#include "Rivet/Projections/Sphericity.hh"
#include "Rivet/Projections/FinalState.hh"
#include "Rivet/Projections/ChargedFinalState.hh"

namespace Rivet {


  /// @brief Average pT w.r.t. thrust and sphericity axes
  class PLUTO_1983_I191161 : public Analysis {
  public:

    /// Constructor
    RIVET_DEFAULT_ANALYSIS_CTOR(PLUTO_1983_I191161);


    /// @name Analysis methods
    /// @{

    /// Book histograms and initialise projections before the run
    void init() {

      // Initialise and register projections
      const FinalState fs;
      declare(fs, "FS");
      declare(ChargedFinalState(), "CFS");
      // Thrust
      const Thrust thrust(fs);
      declare(thrust, "Thrust");
      const Sphericity sphericity(fs);
      declare(sphericity, "Sphericity");

      book(_p_thrust_pt,       1, 1, 1);
      book(_p_thrust_pt2,      1, 1, 2);
      book(_p_thrust_sum_pt,   1, 1, 3);
      book( _p_thrust_sum_pt2, 1, 1, 4);
      book(_p_sphere_pt,       2, 1, 1);
      book(_p_sphere_pt2,      2, 1, 2);
      book(_p_sphere_sum_pt,   2, 1, 3);
      book(_p_sphere_sum_pt2,  2, 1, 4);

      for (const string& en : _p_thrust_pt.binning().edges<0>()) {
        const size_t idx = en.find("-");
        if (idx != string::npos) {
          const double emin = stod(en.substr(0,idx));
          const double emax = stod(en.substr(idx+1,string::npos));
          if (inRange(sqrtS()/GeV, emin, emax)) {
            _sqs = en; break;
          }
          continue;
        }
        if (isCompatibleWithSqrtS(stod(en)*GeV))  _sqs = en;
      }
      raiseBeamErrorIf(_sqs.empty());
    }


    /// Perform the per-event analysis
    void analyze(const Event& event) {
      // at least 4 charged particles
      if (apply<ChargedFinalState>(event, "CFS").particles().size()<4) vetoEvent;
      // Sphericities
      MSG_DEBUG("Calculating sphericity");
      const Sphericity& sphericity = apply<Sphericity>(event, "Sphericity");
      MSG_DEBUG("Calculating thrust");
      const Thrust& thrust = apply<Thrust>(event, "Thrust");
      const FinalState& fs = apply<FinalState>(event, "FS");
      // remove pi0->gammagamma decay products and replace with the pi0s
      // needed to get the average pTs right
      Particles fsParticles;
      set<ConstGenParticlePtr> pi0;
      for (const Particle& p : fs.particles()) {
        if ((p.pid() != PID::PHOTON && p.abspid() != PID::ELECTRON) ||
             p.parents().empty() || p.parents()[0].pid()!=PID::PI0) {
          fsParticles.push_back(p);
        }
        else if (pi0.find(p.parents()[0].genParticle()) == pi0.end()) {
          fsParticles.push_back(p.parents()[0]);
        }
      }
      double pT_T_sum(0.),pT2_T_sum(0.);
      double pT_S_sum(0.),pT2_S_sum(0.);
      for (const Particle& p : fsParticles) {
        const Vector3 mom3 = p.p3();
        const double pTinT = dot(mom3, thrust.thrustMajorAxis());
        const double pToutT = dot(mom3, thrust.thrustMinorAxis());
        const double pTinS = dot(mom3, sphericity.sphericityMajorAxis());
        const double pToutS = dot(mom3, sphericity.sphericityMinorAxis());
        const double pT2_T = sqr(pTinT) + sqr(pToutT);
        const double pT2_S = sqr(pTinS) + sqr(pToutS);
        const double pT_T  = sqrt(pT2_T);
        const double pT_S  = sqrt(pT2_S);
        pT_T_sum  += sqrt(pT2_T);
        pT2_T_sum +=      pT2_T ;
        pT_S_sum  += sqrt(pT2_S);
        pT2_S_sum +=      pT2_S ;
        _p_thrust_pt ->fill(_sqs,pT_T /MeV         );
        _p_thrust_pt2->fill(_sqs,pT2_T/1e3/sqr(MeV));
        _p_sphere_pt ->fill(_sqs,pT_S /MeV         );
        _p_sphere_pt2->fill(_sqs,pT2_S/1e3/sqr(MeV));
      }
      _p_thrust_sum_pt ->fill(_sqs,pT_T_sum /GeV);
      _p_thrust_sum_pt2->fill(_sqs,pT2_T_sum/GeV);
      _p_sphere_sum_pt ->fill(_sqs,pT_S_sum /GeV);
      _p_sphere_sum_pt2->fill(_sqs,pT2_S_sum/GeV);
    }


    /// @}


    /// @name Histograms
    /// @{
    BinnedProfilePtr<string> _p_thrust_pt, _p_thrust_pt2, _p_thrust_sum_pt, _p_thrust_sum_pt2;
    BinnedProfilePtr<string> _p_sphere_pt, _p_sphere_pt2, _p_sphere_sum_pt, _p_sphere_sum_pt2;
    string _sqs = "";
    /// @}

  };


  RIVET_DECLARE_PLUGIN(PLUTO_1983_I191161);
}