Rivet analyses

Measurement of R for energies between 39.8 and 45.2 GeV

Experiment: TASSO (PETRA)

Inspire ID: 199468

Status: VALIDATED

Authors: - Peter Richardson

References: - Phys.Lett. B138 (1984) 441-448, 1984

Beams: e- e+

Beam energies: (19.9, 19.9); (19.9, 19.9); (19.9, 19.9); (19.9, 19.9); (20.0, 20.0); (20.0, 20.0); (20.0, 20.0); (20.0, 20.0); (20.0, 20.0); (20.0, 20.0); (20.0, 20.0); (20.1, 20.1); (20.1, 20.1); (20.1, 20.1); (20.1, 20.1); (20.1, 20.1); (20.1, 20.1); (20.1, 20.1); (20.2, 20.2); (20.2, 20.2); (20.2, 20.2); (20.2, 20.2); (20.2, 20.2); (20.2, 20.2); (20.3, 20.3); (20.3, 20.3); (20.3, 20.3); (20.3, 20.3); (20.3, 20.3); (20.3, 20.3); (20.3, 20.3); (20.4, 20.4); (20.4, 20.4); (20.4, 20.4); (20.4, 20.4); (20.4, 20.4); (20.4, 20.4); (20.4, 20.4); (20.5, 20.5); (20.5, 20.5); (20.5, 20.5); (20.5, 20.5); (20.5, 20.5); (20.5, 20.5); (20.6, 20.6); (20.6, 20.6); (20.6, 20.6); (20.6, 20.6); (20.6, 20.6); (20.6, 20.6); (20.6, 20.6); (20.7, 20.7); (20.7, 20.7); (20.7, 20.7); (20.7, 20.7); (20.7, 20.7); (20.7, 20.7); (20.8, 20.8); (20.8, 20.8); (20.8, 20.8); (20.8, 20.8); (20.8, 20.8); (20.8, 20.8); (20.8, 20.8); (20.9, 20.9); (20.9, 20.9); (20.9, 20.9); (20.9, 20.9); (20.9, 20.9); (20.9, 20.9); (20.9, 20.9); (21.0, 21.0); (21.0, 21.0); (21.0, 21.0); (21.0, 21.0); (21.0, 21.0); (21.0, 21.0); (21.1, 21.1); (21.1, 21.1); (21.1, 21.1); (21.1, 21.1); (21.1, 21.1); (21.1, 21.1); (21.1, 21.1); (21.2, 21.2); (21.2, 21.2); (21.2, 21.2); (21.2, 21.2); (21.2, 21.2); (21.2, 21.2); (21.2, 21.2); (21.3, 21.3); (21.3, 21.3); (21.3, 21.3); (21.3, 21.3); (21.3, 21.3); (21.3, 21.3); (21.4, 21.4); (21.4, 21.4); (21.4, 21.4); (21.4, 21.4); (21.4, 21.4); (21.4, 21.4); (21.4, 21.4); (21.5, 21.5); (21.5, 21.5); (21.5, 21.5); (21.5, 21.5); (21.5, 21.5); (21.5, 21.5); (21.5, 21.5); (21.6, 21.6); (21.6, 21.6); (21.6, 21.6); (21.6, 21.6); (21.6, 21.6); (21.6, 21.6); (21.6, 21.6); (21.7, 21.7); (21.7, 21.7); (21.7, 21.7); (21.7, 21.7); (21.7, 21.7); (21.7, 21.7); (21.8, 21.8); (21.8, 21.8); (21.8, 21.8); (21.8, 21.8); (21.8, 21.8); (21.8, 21.8); (21.8, 21.8); (21.9, 21.9); (21.9, 21.9); (21.9, 21.9); (21.9, 21.9); (21.9, 21.9); (21.9, 21.9); (21.9, 21.9); (22.0, 22.0); (22.0, 22.0); (22.0, 22.0); (22.0, 22.0); (22.0, 22.0); (22.0, 22.0); (22.1, 22.1); (22.1, 22.1); (22.1, 22.1); (22.1, 22.1); (22.1, 22.1); (22.1, 22.1); (22.1, 22.1); (22.2, 22.2); (22.2, 22.2); (22.2, 22.2); (22.2, 22.2); (22.2, 22.2); (22.2, 22.2); (22.2, 22.2); (22.3, 22.3); (22.3, 22.3); (22.3, 22.3); (22.3, 22.3); (22.3, 22.3); (22.3, 22.3); (22.4, 22.4); (22.4, 22.4); (22.4, 22.4); (22.4, 22.4); (22.4, 22.4); (22.4, 22.4); (22.4, 22.4); (22.5, 22.5); (22.5, 22.5); (22.5, 22.5); (22.5, 22.5); (22.5, 22.5); (22.5, 22.5); (22.6, 22.6); (22.6, 22.6); (22.6, 22.6); (22.6, 22.6); (22.6, 22.6)GeV

Run details: - e+ e- to hadrons and e+ e- to mu+ mu- (for normalization)

Measurement of R in e⁺e⁻ collisions for energies between 39.8 and 45.2 GeV. The individual hadronic and muonic cross sections are also outputted to the yoda file so that ratio R can be recalculated if runs are combined.

Source code:TASSO_1984_I199468.cc

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

namespace Rivet {


  /// @brief Measurement of $R$ for energies between 39.8 and 45.2 GeV
  class TASSO_1984_I199468 : public Analysis {
  public:

    /// Constructor
    RIVET_DEFAULT_ANALYSIS_CTOR(TASSO_1984_I199468);


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

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

      // Book histograms
      book(_c_hadrons1, "/TMP/sigma_hadrons1", refData<YODA::BinnedEstimate<string>>(1,1,1));
      book(_c_muons1,   "/TMP/sigma_muons1"  , refData<YODA::BinnedEstimate<string>>(1,1,1));
      book(_c_hadrons2, "/TMP/sigma_hadrons2", refData(2,1,1));
      book(_c_muons2,   "/TMP/sigma_muons2"  , refData(2,1,1));
      for (const string& en : _c_hadrons1.binning().edges<0>()) {
        double eval = stod(en)*GeV;
        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;
      }
      if (nCount[-13]==1 && nCount[13]==1 && ntotal==2+nCount[22]) {
        // mu+mu- + photons
        _c_muons1->fill(_sqs);
        _c_muons2->fill(sqrtS()/GeV);
      }
      else {
        // everything else
        _c_hadrons1->fill(_sqs);
        _c_hadrons2->fill(sqrtS()/GeV);
      }
    }

    /// Normalise histograms etc., after the run
    void finalize() {
      BinnedEstimatePtr<string> ratio1;
      book(ratio1, 1, 1, 1);
      divide(_c_hadrons1, _c_muons1, ratio1);
      Estimate1DPtr ratio2;
      book(ratio2, 2, 1, 1);
      divide(_c_hadrons2, _c_muons2, ratio2);
    }
    /// @}

    /// @name Histograms
    /// @{
    BinnedHistoPtr<string> _c_hadrons1, _c_muons1;
    Histo1DPtr _c_hadrons2, _c_muons2;
    string _sqs = "";
    /// @}

  };


  RIVET_DECLARE_PLUGIN(TASSO_1984_I199468);
}