1// -*- C++ -*-
 2#include "Rivet/Analysis.hh"
 3#include "Rivet/Projections/UnstableParticles.hh"
 4
 5namespace Rivet {
 6
 7
 8  /// @brief Xi_c0 Xi_c+ spectrum in upsilon(4s) decays
 9  class CLEOII_1997_I442910 : public Analysis {
10  public:
11
12    /// Constructor
13    RIVET_DEFAULT_ANALYSIS_CTOR(CLEOII_1997_I442910);
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      // book histos
24      book(_h_Xi_c0   ,1,1,1);
25      book(_h_Xi_cPlus,2,1,1);
26    }
27
28    void findDecayProducts(Particle parent, Particles & Xic) {
29      for(const Particle & p : parent.children()) {
30        int id = abs(p.pid());
31	if(id==4132 || id==4232) {
32	  Xic.push_back(p);
33	}
34	else if(!p.children().empty()) {
35	  findDecayProducts(p,Xic);
36	}
37      }
38    }
39
40    /// Perform the per-event analysis
41    void analyze(const Event& event) {
42      // Find the upsilons
43      for (const Particle& p : apply<UnstableParticles>(event, "UFS").particles(Cuts::pid==300553)) {
44        // Find the decay products we want
45	Particles Xic;
46        findDecayProducts(p, Xic);
47	if(Xic.empty()) continue;
48        LorentzTransform boost;
49        if (p.p3().mod() > 1*MeV)
50          boost = LorentzTransform::mkFrameTransformFromBeta(p.momentum().betaVec());
51
52	for(const Particle & xi : Xic) {
53	  double Emax = sqrt(0.25*sqr(p.mass())-sqr(xi.mass()));
54	  double xp = boost.transform(xi.momentum()).vector3().mod()/Emax;
55	  if(xi.abspid()==4132)
56	    _h_Xi_c0->fill(xp);
57	  else
58	    _h_Xi_cPlus->fill(xp);
59	}
60      }
61    }
62
63
64    /// Normalise histograms etc., after the run
65    void finalize() {
66      // normalize to the data as norm in hepdata is weird
67      normalize(_h_Xi_c0   ,0.144);
68      normalize(_h_Xi_cPlus,0.453);
69
70    }
71
72    /// @}
73
74    /// @name Histograms
75    /// @{
76    Histo1DPtr _h_Xi_c0, _h_Xi_cPlus;
77    /// @}
78
79  };
80
81
82  RIVET_DECLARE_PLUGIN(CLEOII_1997_I442910);
83
84}