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Rivet analyses reference

DM1_1982_I169382

Cross section for $e^+e^-\to K^+K^-\pi^+\pi^-$ between 1.3 and 2.2 GeV
Experiment: DM1 (DCI)
Inspire ID: 169382
Status: VALIDATED
Authors:
  • Peter Richardson
References:
  • Phys.Lett. B110 (1982) 335-338, 1982
Beams: e+ e-
Beam energies: ANY
Run details:
  • e+e- to hadrons

Source code: DM1_1982_I169382.cc
 1// -*- C++ -*-
 2#include "Rivet/Analysis.hh"
 3#include "Rivet/Projections/FinalState.hh"
 4
 5namespace Rivet {
 6
 7
 8  /// @brief Add a short analysis description here
 9  class DM1_1982_I169382 : public Analysis {
10  public:
11
12    /// Constructor
13    RIVET_DEFAULT_ANALYSIS_CTOR(DM1_1982_I169382);
14
15
16    /// @name Analysis methods
17    //@{
18
19    /// Book histograms and initialise projections before the run
20    void init() {
21      // Initialise and register projections
22      declare(FinalState(), "FS");
23      book(_cKpKmpippim, "TMP/KpKmpippim");
24    }
25
26
27    /// Perform the per-event analysis
28    void analyze(const Event& event) {
29      const FinalState& fs = apply<FinalState>(event, "FS");
30
31      map<long,int> nCount;
32      int ntotal(0);
33      for (const Particle& p : fs.particles()) {
34	nCount[p.pid()] += 1;
35	++ntotal;
36      }
37
38      if(ntotal!=4) vetoEvent;
39      if(nCount[321]==1 && nCount[-321]==1 && nCount[211]==1 && nCount[-211]==1)
40	_cKpKmpippim->fill();
41    }
42
43
44    /// Normalise histograms etc., after the run
45    void finalize() {
46      double sigma = _cKpKmpippim->val();
47      double error = _cKpKmpippim->err();
48      sigma *= crossSection()/ sumOfWeights() /nanobarn;
49      error *= crossSection()/ sumOfWeights() /nanobarn;
50      Scatter2D temphisto(refData(1, 1, 1));
51      Scatter2DPtr mult;
52      book(mult, 1, 1, 1);
53      for (size_t b = 0; b < temphisto.numPoints(); b++) {
54	const double x  = temphisto.point(b).x();
55	pair<double,double> ex = temphisto.point(b).xErrs();
56	pair<double,double> ex2 = ex;
57	if(ex2.first ==0.) ex2. first=0.0001;
58	if(ex2.second==0.) ex2.second=0.0001;
59	if (inRange(sqrtS()/GeV, x-ex2.first, x+ex2.second)) {
60	  mult->addPoint(x, sigma, ex, make_pair(error,error));
61	}
62	else {
63	  mult->addPoint(x, 0., ex, make_pair(0.,.0));
64	}
65      }
66    }
67
68    //@}
69
70
71    /// @name Histograms
72    //@{
73    CounterPtr _cKpKmpippim;
74    //@}
75
76
77  };
78
79
80  // The hook for the plugin system
81  RIVET_DECLARE_PLUGIN(DM1_1982_I169382);
82
83
84}