CMS_2011_S8978280.cc

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

namespace Rivet {


  /// @brief CMS strange particle spectra (Ks, Lambda, Cascade) in pp at 900 and 7000 GeV
  /// @author Kevin Stenson
  class CMS_2011_S8978280 : public Analysis {
  public:

    /// Constructor
    CMS_2011_S8978280()
      : Analysis("CMS_2011_S8978280")
    { }


    void init() {
      UnstableFinalState ufs(Cuts::absrap < 2);
      addProjection(ufs, "UFS");

      // Particle distributions versus rapidity and transverse momentum
      if (fuzzyEquals(sqrtS()/GeV, 900*GeV)){
        _h_dNKshort_dy  = bookHisto1D(1, 1, 1);
        _h_dNKshort_dpT = bookHisto1D(2, 1, 1);
        _h_dNLambda_dy  = bookHisto1D(3, 1, 1);
        _h_dNLambda_dpT = bookHisto1D(4, 1, 1);
        _h_dNXi_dy      = bookHisto1D(5, 1, 1);
        _h_dNXi_dpT     = bookHisto1D(6, 1, 1);
        //
        _h_LampT_KpT    = bookScatter2D(7, 1, 1);
        _h_XipT_LampT   = bookScatter2D(8, 1, 1);
        _h_Lamy_Ky      = bookScatter2D(9, 1, 1);
        _h_Xiy_Lamy     = bookScatter2D(10, 1, 1);

      } else if (fuzzyEquals(sqrtS()/GeV, 7000*GeV)){
        _h_dNKshort_dy  = bookHisto1D(1, 1, 2);
        _h_dNKshort_dpT = bookHisto1D(2, 1, 2);
        _h_dNLambda_dy  = bookHisto1D(3, 1, 2);
        _h_dNLambda_dpT = bookHisto1D(4, 1, 2);
        _h_dNXi_dy      = bookHisto1D(5, 1, 2);
        _h_dNXi_dpT     = bookHisto1D(6, 1, 2);
        //
        _h_LampT_KpT    = bookScatter2D(7, 1, 2);
        _h_XipT_LampT   = bookScatter2D(8, 1, 2);
        _h_Lamy_Ky      = bookScatter2D(9, 1, 2);
        _h_Xiy_Lamy     = bookScatter2D(10, 1, 2);
      }
    }


    void analyze(const Event& event) {
      const double weight = event.weight();

      const UnstableFinalState& parts = applyProjection<UnstableFinalState>(event, "UFS");
      foreach (const Particle& p, parts.particles()) {
        switch (p.abspid()) {
        case PID::K0S:
          _h_dNKshort_dy->fill(p.absrap(), weight);
          _h_dNKshort_dpT->fill(p.pT(), weight);
          break;

        case PID::LAMBDA:
          // Lambda should not have Cascade or Omega ancestors since they should not decay. But just in case...
          if ( !( p.hasAncestor(3322) || p.hasAncestor(-3322) || p.hasAncestor(3312) || p.hasAncestor(-3312) || p.hasAncestor(3334) || p.hasAncestor(-3334) ) ) {
            _h_dNLambda_dy->fill(p.absrap(), weight);
            _h_dNLambda_dpT->fill(p.pT(), weight);
          }
          break;

        case PID::XIMINUS:
          // Cascade should not have Omega ancestors since it should not decay.  But just in case...
          if ( !( p.hasAncestor(3334) || p.hasAncestor(-3334) ) ) {
            _h_dNXi_dy->fill(p.absrap(), weight);
            _h_dNXi_dpT->fill(p.pT(), weight);
          }
          break;
        }

      }
    }


    void finalize() {
      divide(_h_dNLambda_dpT,_h_dNKshort_dpT, _h_LampT_KpT);
      divide(_h_dNXi_dpT,_h_dNLambda_dpT, _h_XipT_LampT);
      divide(_h_dNLambda_dy,_h_dNKshort_dy, _h_Lamy_Ky);
      divide(_h_dNXi_dy,_h_dNLambda_dy, _h_Xiy_Lamy);
      const double normpT = 1.0/sumOfWeights();
      const double normy = 0.5*normpT; // Accounts for using |y| instead of y
      scale(_h_dNKshort_dy, normy);
      scale(_h_dNKshort_dpT, normpT);
      scale(_h_dNLambda_dy, normy);
      scale(_h_dNLambda_dpT, normpT);
      scale(_h_dNXi_dy, normy);
      scale(_h_dNXi_dpT, normpT);
    }


  private:

    // Particle distributions versus rapidity and transverse momentum
    Histo1DPtr _h_dNKshort_dy, _h_dNKshort_dpT, _h_dNLambda_dy, _h_dNLambda_dpT, _h_dNXi_dy, _h_dNXi_dpT;
    Scatter2DPtr _h_LampT_KpT, _h_XipT_LampT, _h_Lamy_Ky, _h_Xiy_Lamy;

  };



  // The hook for the plugin system
  DECLARE_RIVET_PLUGIN(CMS_2011_S8978280);

}