Rivet analyses

Measurement of hadronic cross section at the Υ(1S), 9.461 GeV

Experiment: CLEO (CESR)

Inspire ID: 188803

Status: VALIDATED

Authors: - Peter Richardson

References: - Phys.Rev. D57 (1998) 1350-1358, 1998

Beams: e- e+

Beam energies: (4.7, 4.7)GeV

Run details: - e+ e- to hadrons

Measurement of the hadronic cross section in e+e− collisions by CLEO at the Υ(1S), 9.461 GeV.

Source code:CLEO_1983_I188803.cc

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

namespace Rivet {


  /// @brief Hadronic cross section measurement
  class CLEO_1983_I188803 : public Analysis {
  public:

    /// Constructor
    RIVET_DEFAULT_ANALYSIS_CTOR(CLEO_1983_I188803);


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

    /// Book histograms and initialise projections before the run
    void init() {
      // Initialise and register projections
      declare(FinalState(), "FS");

      // Book histograms
      book(_c_hadrons, 2, 1, 1);
      for (const string& en : _c_hadrons.binning().edges<0>()) {
        double eval = stod(en);
        if (isCompatibleWithSqrtS(eval)) {
          _sqs = en; break;
        }
      }
      raiseBeamErrorIf(_sqs.empty());
    }


    /// 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]) vetoEvent;
      else { // everything else
        _c_hadrons->fill(_sqs);
      }
    }


    /// Normalise histograms etc., after the run
    void finalize() {
      scale(_c_hadrons, crossSection()/ sumOfWeights() /nanobarn);
    }

    /// @}


    /// @name Histograms
    /// @{
    BinnedHistoPtr<string> _c_hadrons;
    string _sqs = "";
    /// @}


  };


  RIVET_DECLARE_PLUGIN(CLEO_1983_I188803);


}