Rivet analyses reference

CLEO_2004_I649917

Dalitz decay of $D^0\to K^0_S\pi^0\eta$
Experiment: CLEO (CESR)
Inspire ID: 649917
Status: VALIDATED NOHEPDATA
Authors:

Peter Richardson

References:

Phys.Rev.Lett. 93 (2004) 111801

Beams: * *
Beam energies: ANY
Run details:

Any process producing D0 mesons

Measurement of the mass distributions in the decay $D^0\to K^0_S\pi^0\eta$ by CLEO. The data were read from the plots in the paper. It is also not clear that any resolution effects have been unfolded.

Source code: CLEO_2004_I649917.cc

 1// -*- C++ -*-
 2#include "Rivet/Analysis.hh"
 3#include "Rivet/Projections/UnstableParticles.hh"
 4#include "Rivet/Projections/DecayedParticles.hh"
 5
 6namespace Rivet {
 7
 8
 9  /// @brief D0 -> KS0 pi0 eta
10  class CLEO_2004_I649917 : public Analysis {
11  public:
12
13    /// Constructor
14    RIVET_DEFAULT_ANALYSIS_CTOR(CLEO_2004_I649917);
15
16
17    /// @name Analysis methods
18    /// @{
19
20    /// Book histograms and initialise projections before the run
21    void init() {
22      // Initialise and register projections
23      UnstableParticles ufs = UnstableParticles(Cuts::abspid==421);
24      declare(ufs, "UFS");
25      DecayedParticles D0(ufs);
26      D0.addStable(PID::PI0);
27      D0.addStable(PID::K0S);
28      D0.addStable(PID::ETA);
29      D0.addStable(PID::ETAPRIME);
30      declare(D0, "D0");
31      // histograms
32      book(_h_Kpi  ,1,1,1);
33      book(_h_etapi,1,1,2);
34      book(_h_Keta ,1,1,3);
35      book(_dalitz, "dalitz",50,0.4,1.9,50,0.3,1.8);
36    }
37
38    /// Perform the per-event analysis
39    void analyze(const Event& event) {
40      // define the decay mode
41      static const map<PdgId,unsigned int> & mode   = { { 310,1}, { 221,1},{ 111,1}};
42      DecayedParticles D0 = apply<DecayedParticles>(event, "D0");
43      // loop over particles
44      for(unsigned int ix=0;ix<D0.decaying().size();++ix) {
45	if ( ! D0.modeMatches(ix,3,mode)) continue;
46	const Particles & pi0= D0.decayProducts()[ix].at(111);
47	const Particles & eta= D0.decayProducts()[ix].at(221);
48	const Particles & K0 = D0.decayProducts()[ix].at(310);
49	double metapi = (eta[0].momentum()+pi0[0].momentum()).mass2();
50	double metaK  = (eta[0].momentum()+ K0[0].momentum()).mass2();
51	double mKpi   = ( K0[0].momentum()+pi0[0].momentum()).mass2();
52	_dalitz ->fill(metapi,mKpi);
53	_h_etapi->fill(metapi);
54	_h_Keta ->fill(metaK );
55	_h_Kpi  ->fill(mKpi);
56      }
57    }
58
59
60    /// Normalise histograms etc., after the run
61    void finalize() {
62      normalize(_h_Kpi  );
63      normalize(_h_etapi);
64      normalize(_h_Keta );
65      normalize(_dalitz );
66    }
67
68    /// @}
69
70
71    /// @name Histograms
72    /// @{
73    Histo1DPtr _h_Kpi,_h_etapi,_h_Keta;
74    Histo2DPtr _dalitz;
75    /// @}
76
77
78  };
79
80
81  RIVET_DECLARE_PLUGIN(CLEO_2004_I649917);
82
83}