Rivet analyses

// -*- C++ -*-
#include "Rivet/Analysis.hh"
#include "Rivet/Projections/UnstableParticles.hh"
#include "Rivet/Projections/ChargedFinalState.hh"

namespace Rivet {


  /// @brief Xi- and Sigma*+/- spectra
  class HRS_1987_I246162 : public Analysis {
  public:

    /// Constructor
    RIVET_DEFAULT_ANALYSIS_CTOR(HRS_1987_I246162);


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

    /// Book histograms and initialise projections before the run
    void init() {
      // projects
      declare(UnstableParticles(Cuts::abspid==3114 || Cuts::abspid==3224 ||
                                Cuts::abspid==3312 || Cuts::abspid==3122), "UFS");
      const ChargedFinalState cfs;
      declare(cfs, "CFS");
      // histos
      for (unsigned int ix=0; ix<2; ++ix) {
        for(unsigned int iy=0;iy<2;++iy)
          book(_h_total[ix][iy],1+ix,1,1+iy);
        book(_h_x[ix],4,1,1+ix);
        book(_h_ratio[ix],3,1,1+ix);
      }
      book(_c,"TMP/nLam");
    }


    /// Perform the per-event analysis
    void analyze(const Event& event) {
      const ChargedFinalState& cfs = apply<ChargedFinalState>(event, "CFS");
      const size_t numParticles = cfs.particles().size();

      // Even if we only generate hadronic events, we still need a cut on numCharged >= 2.
      if (numParticles < 2) {
        MSG_DEBUG("Failed leptonic event cut");
        vetoEvent;
      }
      MSG_DEBUG("Passed leptonic event cut");
      for(const Particle & p : apply<UnstableParticles>(event,"UFS").particles()) {
        if(p.abspid()==3122) {
          _c->fill();
          continue;
        }
        double xE = 2.*p.E()/sqrtS();
        Vector3 mom3 = p.p3();
        const double energy = p.E();
        double modp = mom3.mod();
        double beta = modp/energy;
        unsigned int iloc = p.abspid()==3312 ? 1 : 0;
        _h_ratio[iloc]->fill(29);
        if(iloc==0&&xE>0.1&&xE<0.8) 
          _h_total[iloc][0]->fill(29);
        else if(iloc==1&&xE>0.05&&xE<0.75)
          _h_total[iloc][0]->fill(29);
        _h_total[iloc][1]->fill(29);
        _h_x[iloc]->fill(xE,1./beta);
      }
    }


    /// Normalise histograms etc., after the run
    void finalize() {
      for (unsigned int ix=0; ix<2; ++ix) {
        scale(_h_total[ix],1./sumOfWeights());
        scale(_h_x[ix], sqr(sqrtS())*crossSection()/nanobarn/sumOfWeights());
        scale(_h_ratio[ix], 1./ *_c);
      }
    }

    /// @}


    /// @name Histograms
    /// @{
    BinnedHistoPtr<int> _h_total[2][2],_h_ratio[2];
    Histo1DPtr _h_x[2];
    CounterPtr _c;
    /// @}


  };


  RIVET_DECLARE_PLUGIN(HRS_1987_I246162);

}