Rivet Analyses Reference

CMD3_2016_I1444990

Cross section for $e^+e^-\to K^0_SK^0_L$ at energies between 1.004 and 1.06 GeV
Experiment: CMD3 (VEPP-2M)
Inspire ID: 1444990
Status: VALIDATED
Authors:
  • Peter Richardson
References:
  • Phys.Lett. B760 (2016) 314-319, 2016
Beams: e+ e-
Beam energies: ANY
Run details:
  • e+e- to hadrons

Source code: CMD3_2016_I1444990.cc
 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
// -*- C++ -*-
#include "Rivet/Analysis.hh"
#include "Rivet/Projections/FinalState.hh"


namespace Rivet {


  /// @brief Add a short analysis description here
  class CMD3_2016_I1444990 : public Analysis {
  public:

    /// Constructor
    RIVET_DEFAULT_ANALYSIS_CTOR(CMD3_2016_I1444990);


    /// @name Analysis methods
    //@{

    /// Book histograms and initialise projections before the run
    void init() {
      
      declare(FinalState(), "FS");
      book(_nK0K0, "TMP/K0K0");

    }


    /// 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(ntotal==2 &&
	 nCount[130]==1 && nCount[310]==1)
	_nK0K0->fill();
    }


    /// Normalise histograms etc., after the run
    void finalize() {
      double sigma = _nK0K0->val();
      double error = _nK0K0->err();
      sigma *= crossSection()/ sumOfWeights() /nanobarn;
      error *= crossSection()/ sumOfWeights() /nanobarn;
      Scatter2D temphisto(refData(1, 1, 6));
      Scatter2DPtr mult;
      book(mult, 1, 1, 6);
      for (size_t b = 0; b < temphisto.numPoints(); b++) {
	const double x  = temphisto.point(b).x();
	pair<double,double> ex = temphisto.point(b).xErrs();
	pair<double,double> ex2 = ex;
	if(ex2.first ==0.) ex2. first=0.0001;
	if(ex2.second==0.) ex2.second=0.0001;
	if (inRange(sqrtS()/MeV, x-ex2.first, x+ex2.second)) {
	  mult->addPoint(x, sigma, ex, make_pair(error,error));
	}
	else {
	  mult->addPoint(x, 0., ex, make_pair(0.,.0));
	}
      }
    }

    //@}


    /// @name Histograms
    //@{
    CounterPtr _nK0K0;
    //@}


  };


  // The hook for the plugin system
  RIVET_DECLARE_PLUGIN(CMD3_2016_I1444990);


}