1// -*- C++ -*-
 2#include "Rivet/Analysis.hh"
 3#include "Rivet/Projections/UnstableParticles.hh"
 4
 5namespace Rivet {
 6
 7
 8  /// @brief ARGUS lepton spectra
 9  class ARGUS_1990_I298245 : public Analysis {
10  public:
11
12    /// Constructor
13    RIVET_DEFAULT_ANALYSIS_CTOR(ARGUS_1990_I298245);
14
15
16    /// @name Analysis methods
17    /// @{
18
19    /// Book histograms and initialise projections before the run
20    void init() {
21      // projections
22      declare(UnstableParticles(),"UFS");
23      // histograms
24      for (unsigned int ix=0; ix<2; ++ix) {
25        book(_h[ix], 2,1,1+ix);
26      }
27      book(_c,"TMP/nb");
28    }
29
30
31    void findDecayProducts(const Particle& parent, Particles& ee, Particles& mu) {
32      for (const Particle& p : parent.children()) {
33      	if (p.abspid() == PID::EMINUS) {
34          ee.push_back(p);
35        }
36        else if (p.abspid() == PID::MUON) {
37          mu.push_back(p);
38        }
39      	else if (!p.children().empty()) {
40      	  findDecayProducts(p,ee,mu);
41      	}
42      }
43    }
44
45    /// Perform the per-event analysis
46    void analyze(const Event& event) {
47      const UnstableParticles& ufs = apply<UnstableParticles>(event, "UFS");
48      for (const Particle& p : ufs.particles(Cuts::pid==300553)) {
49      	// boost to rest frame
50      	LorentzTransform cms_boost;
51      	if (p.p3().mod() > 1*MeV) {
52      	  cms_boost = LorentzTransform::mkFrameTransformFromBeta(p.mom().betaVec());
53        }
54      	// loop over decay products
55      	for (const Particle& p2 : p.children()) {
56      	  if (p2.abspid()==511 || p2.abspid()==521) {
57      	    _c->fill();
58            // find decay products
59            Particles leptons[2];
60            findDecayProducts(p2, leptons[0], leptons[1]);
61            for (unsigned int ix=0; ix<2; ++ix) {
62              for (const Particle& lep : leptons[ix]) {
63                FourMomentum pl = cms_boost.transform(lep.mom());
64                _h[ix]->fill(pl.p3().mod());
65              }
66            }
67          }
68        }
69      }
70    }
71
72
73    /// Normalise histograms etc., after the run
74    void finalize() {
75      scale(_h, 1.0/ *_c);
76    }
77
78    /// @}
79
80
81    /// @name Histograms
82    /// @{
83    Histo1DPtr _h[2];
84    CounterPtr _c;
85    /// @}
86
87
88  };
89
90
91  RIVET_DECLARE_PLUGIN(ARGUS_1990_I298245);
92
93}