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Rivet analyses reference

TASSO_1980_I143691

Charged Particle distributions between 13 and 31.6 GeV
Experiment: TASSO (Petra)
Inspire ID: 143691
Status: VALIDATED
Authors:
  • Peter Richardson
References:
  • Phys.Lett. 89B (1980) 418-422
Beams: e- e+
Beam energies: (6.5, 6.5); (8.5, 8.5); (11.0, 11.0); (13.8, 13.8); (15.2, 15.2); (15.6, 15.6) GeV
Run details:
  • e+ e- to hadrons and e+ e- to mu+ mu- (for normalization). Beam energy must be specified as analysis option "ENERGY" when rivet-merging samples.

Measurement of charged particle multiplicity, rapidity and scaled momentum distributions for a range of energies between 13 and 31.6 GeV. Beam energy must be specified as analysis option "ENERGY" when rivet-merging samples.

Source code: TASSO_1980_I143691.cc
  1// -*- C++ -*-
  2#include "Rivet/Analysis.hh"
  3#include "Rivet/Projections/Beam.hh"
  4#include "Rivet/Projections/ChargedFinalState.hh"
  5#include "Rivet/Projections/Thrust.hh"
  6
  7namespace Rivet {
  8
  9
 10  /// @brief Charged particle multiplicities and distributions
 11  class TASSO_1980_I143691 : public Analysis {
 12  public:
 13
 14    /// Constructor
 15    RIVET_DEFAULT_ANALYSIS_CTOR(TASSO_1980_I143691);
 16
 17
 18    /// @name Analysis methods
 19    /// @{
 20
 21    /// Book histograms and initialise projections before the run
 22    void init() {
 23
 24      // Initialise and register projections
 25      ChargedFinalState cfs;
 26      declare(cfs, "CFS");
 27      declare(Thrust(cfs), "Thrust");
 28
 29
 30      // Book histograms
 31      book(_mult, "/TMP/mult");
 32      unsigned int iloc(0);
 33      sqs = 1.0;
 34      if(isCompatibleWithSqrtS(13*GeV)) {
 35	iloc = 1;
 36	sqs = 13.0;
 37      }
 38      else if(isCompatibleWithSqrtS(17*GeV)) {
 39	iloc = 2;
 40        sqs = 17.0;
 41      }
 42      else if (isCompatibleWithSqrtS(22*GeV)) {
 43	iloc = 2;
 44	sqs = 22.;
 45      }
 46      else if(isCompatibleWithSqrtS(27.6*GeV)) {
 47	iloc = 3;
 48	sqs = 27.6;
 49      }
 50      else if (isCompatibleWithSqrtS(30.3*GeV)) {
 51	iloc = 3;
 52	sqs = 30.3;
 53      }
 54      else if (isCompatibleWithSqrtS(31.2*GeV)) {
 55	iloc = 3;
 56	sqs = 31.2;
 57      }
 58      else
 59	MSG_ERROR("Beam energy not supported!");
 60
 61      book(_h_rap,iloc+1,1,1);
 62      book(_h_x  ,iloc+4,1,1);
 63    }
 64
 65
 66    /// Perform the per-event analysis
 67    void analyze(const Event& event) {
 68      const ChargedFinalState& cfs = apply<ChargedFinalState>(event, "CFS");
 69      // thrust
 70      const Thrust& thrust = apply<Thrust>(event, "Thrust");
 71      Vector3 axis=thrust.thrustAxis();
 72      for (const Particle& p : cfs.particles()) {
 73	const Vector3 mom3 = p.p3();
 74	double pp = mom3.mod();
 75	double xP = 2.*pp/sqs;
 76	_h_x->fill(xP);
 77        const double mom = dot(axis, mom3);
 78	const double rap = 0.5 * log((p.E() + mom) /
 79				     (p.E() - mom));
 80	_h_rap->fill(fabs(rap));
 81	_mult->fill();
 82      }
 83    }
 84
 85
 86    /// Normalise histograms etc., after the run
 87    void finalize() {
 88
 89      scale(_h_rap, 1./sumOfWeights());
 90      scale(_h_x  , crossSection()*sqr(sqs)/sumOfWeights()/microbarn);
 91
 92      scale(_mult,1./sumOfWeights());
 93
 94      Estimate1DPtr     mult;
 95      book(mult,1, 1, 1);
 96      for (auto& b : mult->bins()) {
 97        if (inRange(sqs, b.xMin(), b.xMax())) {
 98          b.set(_mult->val(), _mult->err());
 99        }
100      }
101    }
102
103    /// @}
104
105
106    /// @name Histograms
107    /// @{
108    Histo1DPtr _h_rap, _h_x;
109    CounterPtr _mult;
110    double sqs;
111    /// @}
112
113
114  };
115
116
117  RIVET_DECLARE_PLUGIN(TASSO_1980_I143691);
118
119
120}