Rivet analyses

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

namespace Rivet {


  /// @brief e+e- > hadrons
  class GAMMAGAMMA_1981_I158474 : public Analysis {
  public:

    /// Constructor
    RIVET_DEFAULT_ANALYSIS_CTOR(GAMMAGAMMA_1981_I158474);


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

    /// Book histograms and initialise projections before the run
    void init() {
      // Initialise and register projections
      declare(FinalState(), "FS");
      for (unsigned int ix = 0; ix < 6; ++ix)
        book(_h[ix], "TMP/h_" + toString(ix + 1), refData(1, 1, 1 + ix));
      for (unsigned int ix = 6; ix < 9; ++ix) book(_h[ix], "TMP/h_" + toString(ix + 1), refData(2, 1, 1));
    }


    /// Perform the per-event analysis
    void analyze(const Event& event) {
      const FinalState& fs = apply<FinalState>(event, "FS");

      map<long, int> nCount;
      int ntotal(0);
      for (const Particle& p : fs.particles()) {
        nCount[p.pid()] += 1;
        ++ntotal;
      }
      // mu+mu- + photons
      if (nCount[-13] == 1 and nCount[13] == 1 && ntotal == 2 + nCount[22])
        _h[8]->fill(sqrtS());
      else {
        if (ntotal == 3 && nCount[211] == 1 && nCount[-211] == 1 && nCount[111] == 1) {
          _h[0]->fill(sqrtS());
        }
        if (ntotal == 4 && nCount[211] == 1 && nCount[-211] == 1 && nCount[111] == 2) {
          _h[1]->fill(sqrtS());
        }
        if (ntotal == 5 && nCount[211] == 2 && nCount[-211] == 2 && nCount[111] == 1) {
          _h[2]->fill(sqrtS());
        }
        if (ntotal == 6 && nCount[211] == 2 && nCount[-211] == 2 && nCount[111] == 2) {
          _h[3]->fill(sqrtS());
        }
        if (nCount[211] == 1 && nCount[-211] == 1 && ntotal == 2 + nCount[111]) {
          _h[6]->fill(sqrtS());
        }
        if (nCount[211] == 2 && nCount[-211] == 2 && ntotal == 4 + nCount[111]) {
          _h[7]->fill(sqrtS());
        }
        if ((nCount[211] + nCount[-211] + nCount[111]) == ntotal) {
          if (ntotal == 3 || ntotal == 5)
            _h[4]->fill(sqrtS());
          else if (ntotal == 4 || ntotal == 6)
            _h[5]->fill(sqrtS());
        }
      }
    }


    /// Normalise histograms etc., after the run
    void finalize() {
      double fact = crossSection() / sumOfWeights() / nanobarn;
      for (unsigned int ix = 0; ix < 9; ++ix) {
        scale(_h[ix], fact);
        if (ix >= 6) continue;
        Estimate1DPtr tmp;
        book(tmp, 1, 1, 1 + ix);
        barchart(_h[ix], tmp);
      }
      Estimate1DPtr tmp;
      book(tmp, 2, 1, 1);
      divide(_h[6], _h[8], tmp);
      book(tmp, 2, 1, 2);
      divide(_h[7], _h[8], tmp);
    }

    /// @}


    /// @name Histograms
    /// @{
    Histo1DPtr _h[9];
    /// @}
  };


  RIVET_DECLARE_PLUGIN(GAMMAGAMMA_1981_I158474);


}