1// -*- C++ -*-
 2#include "Rivet/Analysis.hh"
 3#include "Rivet/Projections/UnstableParticles.hh"
 4
 5namespace Rivet {
 6
 7
 8  /// @brief  J/psi at 5.02 TeV
 9  class ALICE_2019_I1735351 : public Analysis {
10  public:
11
12    /// Constructor
13    RIVET_DEFAULT_ANALYSIS_CTOR(ALICE_2019_I1735351);
14
15
16    /// @name Analysis methods
17    /// @{
18
19    /// Book histograms and initialise projections before the run
20    void init() {
21      declare(UnstableParticles(Cuts::pid==443), "UFS");
22      book(_h_JPsi_pT,2,1,1);
23      _axis = YODA::Axis<double>({ 0., 1., 2., 3., 4., 5., 7., 10. });
24    }
25
26    /// Perform the per-event analysis
27    void analyze(const Event& event) {
28      if (_edges.empty())  _edges = _h_JPsi_pT->xEdges();
29      // loop over J/Psi
30      for (const Particle& p : apply<UnstableParticles>(event, "UFS").particles()) {
31        // rapidity cut
32        if (p.absrap()>0.9) continue;
33        _h_JPsi_pT->fill(discEdge(p.perp()));
34      }
35    }
36
37    string discEdge(double val) const {
38      string edge("OTHER");
39      size_t idx = _axis.index(val);
40      if (0 < idx && idx <= _axis.numBins())  return _edges[idx-1];
41      return edge;
42    }
43
44
45    /// Normalise histograms etc., after the run
46    void finalize() {
47      // factor 1/2 due folding +/- rap and 1.8 due y range
48      double fact = 0.5/1.8*crossSection()/nanobarn/sumOfWeights();
49      scale(_h_JPsi_pT,fact);
50      for(auto & b : _h_JPsi_pT->bins()) {
51        b.scaleW(1./_axis.width(b.index()));
52      }
53    }
54
55    /// @}
56
57
58    /// @name Histograms
59    /// @{
60    BinnedHistoPtr<string> _h_JPsi_pT;
61    YODA::Axis<double> _axis;
62    vector<string> _edges;
63    /// @}
64
65
66  };
67
68
69  RIVET_DECLARE_PLUGIN(ALICE_2019_I1735351);
70
71}