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Rivet analyses reference

OPAL_2000_I513476

Event Shapes at 172, 183 and 189 GeV
Experiment: OPAL (LEP)
Inspire ID: 513476
Status: VALIDATED
Authors:
  • Peter Richardson
References:
  • Eur.Phys.J. C16 (2000) 185-210
Beams: e- e+
Beam energies: (86.0, 86.0); (91.5, 91.5); (94.5, 94.5) GeV
Run details:
  • e+e- to hadrons. Beam energy must be specified as analysis option "ENERGY" when rivet-merging samples.

Event shapes at 172, 183 and 189 GeV. Beam energy must be specified as analysis option "ENERGY" when rivet-merging samples.

Source code: OPAL_2000_I513476.cc
  1// -*- C++ -*-
  2#include "Rivet/Analysis.hh"
  3#include "Rivet/Projections/Beam.hh"
  4#include "Rivet/Projections/FinalState.hh"
  5#include "Rivet/Projections/ChargedFinalState.hh"
  6#include "Rivet/Projections/Sphericity.hh"
  7#include "Rivet/Projections/Thrust.hh"
  8#include "Rivet/Projections/FastJets.hh"
  9#include "Rivet/Projections/ParisiTensor.hh"
 10#include "Rivet/Projections/Hemispheres.hh"
 11
 12namespace Rivet {
 13
 14
 15  /// @brief  event shapes at 172, 183, 189
 16  class OPAL_2000_I513476 : public Analysis {
 17  public:
 18
 19    /// Constructor
 20    RIVET_DEFAULT_ANALYSIS_CTOR(OPAL_2000_I513476);
 21
 22
 23    /// @name Analysis methods
 24    //@{
 25
 26    /// Book histograms and initialise projections before the run
 27    void init() {
 28
 29      // Initialise and register projections
 30      // Projections
 31      declare(Beam(), "Beams");
 32      const FinalState fs;
 33      declare(fs, "FS");
 34      const ChargedFinalState cfs;
 35      declare(cfs, "CFS");
 36      declare(FastJets(fs, FastJets::DURHAM, 0.7), "DurhamJets");
 37      declare(Sphericity(fs), "Sphericity");
 38      declare(ParisiTensor(fs), "Parisi");
 39      const Thrust thrust(fs);
 40      declare(thrust, "Thrust");
 41      declare(Hemispheres(thrust), "Hemispheres");
 42
 43      // Book histograms
 44      int ih=-1;
 45      if (isCompatibleWithSqrtS(172.)) {
 46        ih = 1;
 47      } else if (isCompatibleWithSqrtS(183.)) {
 48        ih = 2;
 49      } else if (isCompatibleWithSqrtS(189.)) {
 50        ih = 3;
 51      }
 52      else {
 53        throw Error("Invalid CMS energy for OPAL_2000_I513476");
 54      }
 55      book(_h_thrust    ,  1,1,ih);
 56      book(_h_major     ,  2,1,ih);
 57      book(_h_minor     ,  3,1,ih);
 58      book(_h_aplanarity,  4,1,ih);
 59      book(_h_oblateness,  5,1,ih);
 60      book(_h_C         ,  6,1,ih);
 61      book(_h_rhoH      ,  7,1,ih);
 62      book(_h_sphericity,  8,1,ih);
 63      book(_h_totalB    ,  9,1,ih);
 64      book(_h_wideB     , 10,1,ih);
 65      book(_h_y23       , 11,1,ih);
 66      book(_h_mult      , 13,1,ih);
 67      book(_h_pTin      , 15,1,ih);
 68      book(_h_pTout     , 16,1,ih);
 69      book(_h_y         , 17,1,ih);
 70      book(_h_x         , 18,1,ih);
 71      book(_h_xi        , 19,1,ih);
 72      book(_sumW,"/TMP/sumW");
 73    }
 74
 75
 76    /// Perform the per-event analysis
 77    void analyze(const Event& event) {
 78      // Even if we only generate hadronic events, we still need a cut on numCharged >= 2.
 79      const FinalState& cfs = apply<FinalState>(event, "CFS");
 80      if (cfs.size() < 2) vetoEvent;
 81
 82      _sumW->fill();
 83      
 84      // Get beams and average beam momentum
 85      const ParticlePair& beams = apply<Beam>(event, "Beams").beams();
 86      const double meanBeamMom = ( beams.first.p3().mod() +
 87                                   beams.second.p3().mod() ) / 2.0;
 88      
 89      // Thrust related
 90      const Thrust& thrust = apply<Thrust>(event, "Thrust");
 91      _h_thrust    ->fill(thrust.thrust()     );
 92      _h_major     ->fill(thrust.thrustMajor());
 93      _h_minor     ->fill(thrust.thrustMinor());
 94      _h_oblateness->fill(thrust.oblateness() );
 95
 96      // Sphericity related
 97      const Sphericity& sphericity = apply<Sphericity>(event, "Sphericity");
 98      _h_sphericity->fill(sphericity.sphericity());
 99      _h_aplanarity->fill(sphericity.aplanarity());
100      
101      // C parameter
102      const ParisiTensor& parisi = apply<ParisiTensor>(event, "Parisi");
103      _h_C->fill(parisi.C());
104
105      // Hemispheres
106      const Hemispheres& hemi = apply<Hemispheres>(event, "Hemispheres");
107
108      _h_rhoH  ->fill(hemi.scaledMhigh());
109      _h_wideB ->fill(hemi.Bmax());
110      _h_totalB->fill(hemi.Bsum());
111      
112      // Jets
113      const FastJets& durjet = apply<FastJets>(event, "DurhamJets");
114      const double y23 = durjet.clusterSeq()->exclusive_ymerge_max(2);
115      _h_y23->fill(y23);
116
117      // charged particles
118      _h_mult->fill(cfs.particles().size());
119      for (const Particle& p : cfs.particles()) {
120        const Vector3 mom3  = p.p3();
121        const double energy = p.E();
122        const double pTinT  = dot(mom3, thrust.thrustMajorAxis());
123        const double pToutT = dot(mom3, thrust.thrustMinorAxis());
124      	_h_pTin ->fill(fabs(pTinT/GeV) );
125      	_h_pTout->fill(fabs(pToutT/GeV));
126        const double momT = dot(thrust.thrustAxis(), mom3);
127        const double rapidityT = 0.5 * std::log((energy + momT) / (energy - momT));
128      	_h_y->fill(fabs(rapidityT));
129        const double mom = mom3.mod();
130        const double scaledMom = mom/meanBeamMom;
131        const double logInvScaledMom = -std::log(scaledMom);
132        _h_xi->fill(logInvScaledMom);
133        _h_x ->fill(scaledMom      );
134      }
135    }
136
137
138    /// Normalise histograms etc., after the run
139    void finalize() {
140      scale(_h_thrust    ,1./ *_sumW);
141      scale(_h_major     ,1./ *_sumW);
142      scale(_h_minor     ,1./ *_sumW);
143      scale(_h_aplanarity,1./ *_sumW);
144      scale(_h_oblateness,1./ *_sumW);
145      scale(_h_C         ,1./ *_sumW);
146      scale(_h_rhoH      ,1./ *_sumW);
147      scale(_h_sphericity,1./ *_sumW);
148      scale(_h_totalB    ,1./ *_sumW);
149      scale(_h_wideB     ,1./ *_sumW);
150      scale(_h_y23       ,1./ *_sumW);
151      scale(_h_mult      ,200./ *_sumW);
152      scale(_h_pTin      ,1./ *_sumW);
153      scale(_h_pTout     ,1./ *_sumW);
154      scale(_h_y         ,1./ *_sumW);
155      scale(_h_x         ,1./ *_sumW);
156      scale(_h_xi        ,1./ *_sumW);
157      // mean multiplicity
158      double nch     = _h_mult->xMean();
159      double nch_err = _h_mult->xStdErr();
160      Scatter2DPtr m_ch;
161      book(m_ch,14,1,1);
162      m_ch->addPoint(sqrtS()/GeV,nch,0.,nch_err);
163      // mean ptIn
164      double pTin     = _h_pTin->xMean();
165      double pTin_err = _h_pTin->xStdErr();
166      Scatter2DPtr m_pTin;
167      book(m_pTin,20,1,1);
168      m_pTin->addPoint(sqrtS()/GeV,pTin,0.,pTin_err);
169      // mean ptOut
170      double pTout     = _h_pTout->xMean();
171      double pTout_err = _h_pTout->xStdErr();
172      Scatter2DPtr m_pTout;
173      book(m_pTout,20,1,2);
174      m_pTout->addPoint(sqrtS()/GeV,pTout,0.,pTout_err);
175      // mean y
176      double y     = _h_y->xMean();
177      double y_err = _h_y->xStdErr();
178      Scatter2DPtr m_y;
179      book(m_y,20,1,3);
180      m_y->addPoint(sqrtS()/GeV,y,0.,y_err);
181      // mean x
182      double x     = _h_x->xMean();
183      double x_err = _h_x->xStdErr();
184      Scatter2DPtr m_x;
185      book(m_x,20,1,4);
186      m_x->addPoint(sqrtS()/GeV,x,0.,x_err);
187    }
188
189    //@}
190
191
192    /// @name Histograms
193    //@{
194    Histo1DPtr _h_thrust,_h_major,_h_minor,_h_aplanarity,_h_oblateness,_h_C,_h_rhoH,_h_sphericity;
195    Histo1DPtr _h_totalB,_h_wideB,_h_y23,_h_mult,_h_pTin,_h_pTout,_h_y,_h_x,_h_xi;
196    CounterPtr _sumW;
197    //@}
198
199
200  };
201
202
203  // The hook for the plugin system
204  RIVET_DECLARE_PLUGIN(OPAL_2000_I513476);
205
206
207}