Rivet analyses

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

namespace Rivet {


  /// @brief chi_c production at 7 TeV
  class ATLAS_2014_I1292798 : public Analysis {
  public:

    /// Constructor
    RIVET_DEFAULT_ANALYSIS_CTOR(ATLAS_2014_I1292798);


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

    /// Book histograms and initialise projections before the run
    void init() {
      declare(UnstableParticles(Cuts::pid==443 || Cuts::pid==20443 || Cuts::pid==445), "UFS");
      for (unsigned int ichi=0; ichi<2; ++ichi) {
        for (unsigned int ipT=0; ipT<2; ++ipT) {
          for (unsigned int iprompt=0; iprompt<2; ++iprompt) {
            book(_h_pT[ichi][iprompt][ipT], 1+ichi+2*iprompt+4*ipT, 1, 1);
          }
          book(_h_pT[ichi][2][ipT],
               "TMP/chi_"+toString(ichi)+"_"+toString(ipT),
               refData(1+ichi+4*ipT,1,1));
        }
      }
      for (unsigned int iprompt=0; iprompt<2; ++iprompt) {
        for (unsigned int ifeed=0; ifeed<2; ++ifeed) {
          book(_h_Jpsi[iprompt][ifeed],
               "TMP/jpsi_"+toString(iprompt)+"_"+toString(ifeed),
               refData(9+iprompt,1,1));
        }
      }
    }


    /// Perform the per-event analysis
    void analyze(const Event& event) {

      // Final state of unstable particles to get particle spectra
      const UnstableParticles& ufs = apply<UnstableParticles>(event, "UFS");

      for (const Particle& p : ufs.particles()) {
        // prompt/non-prompt
        bool nonPrompt = p.fromBottom();
        // J/psi as a reference
        if (p.pid()==443) {
          if (p.absrap()<0.75) _h_Jpsi[nonPrompt][0]->fill(p.perp());
        }
        else if (p.children().size()==2) {
          Particle Jpsi;
          if(p.children()[0].pid()==22 && p.children()[1].pid()==443) {
            Jpsi=p.children()[1];
          }
          else if(p.children()[1].pid()==22 && p.children()[0].pid()==443) {
            Jpsi=p.children()[0];
          }
          else  continue;
          if (Jpsi.absrap()>0.75) continue;
          unsigned int ichi = p.pid()==20443 ? 0 : 1;
          _h_Jpsi[nonPrompt][1]->fill(Jpsi.perp());
          _h_pT[ichi][nonPrompt][0]->fill(Jpsi.perp());
          _h_pT[ichi][nonPrompt][1]->fill(p   .perp());
          _h_pT[ichi][2        ][0]->fill(Jpsi.perp());
          _h_pT[ichi][2        ][1]->fill(p   .perp());
        }
      }
    }


    /// Normalise histograms etc., after the run
    void finalize() {
      // J/psi -> mu+mu- branching ratio
      const double br = 0.05961;
      const double fact = br*crossSection()/picobarn/sumOfWeights();
      for (unsigned int iprompt=0; iprompt<3; ++iprompt) {
        for (unsigned int ichi=0; ichi<2; ++ichi) {
          for (unsigned int ipT=0; ipT<2; ++ipT) {
            scale(_h_pT[ichi][iprompt][ipT],fact);
          }
        }
      }
      for (unsigned int iprompt=0; iprompt<2; ++iprompt) {
        for (unsigned int ifeed=0; ifeed<2; ++ifeed) {
          scale(_h_Jpsi[iprompt][ifeed], fact);
        }
      }
      // Jpsi feed down prompt
      Estimate1DPtr tmp;
      book(tmp,9,1,1);
      efficiency(_h_Jpsi[0][1], _h_Jpsi[0][0], tmp);
      // ratio prompt chi2/chi1
      book(tmp,10,1,1);
      divide(_h_pT[1][0][0], _h_pT[0][0][0], tmp);
      // ratio non-prompt chi2/chi1
      book(tmp,11,1,1);
      divide(_h_pT[1][1][0], _h_pT[0][1][0], tmp);
      // ratio non-prmopt chi1
      book(tmp,12,1,1);
      divide(_h_pT[0][1][1], _h_pT[0][2][1], tmp);
      // ratio non-prmopt chi2
      book(tmp,13,1,1);
      divide(_h_pT[1][1][1], _h_pT[1][2][1], tmp);
    }

    /// @}


    /// @name Histograms
    /// @{
    Histo1DPtr _h_pT[2][3][2],_h_Jpsi[2][2];
    /// @}


  };


  RIVET_DECLARE_PLUGIN(ATLAS_2014_I1292798);

}