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BESIII_2020_I1808166

Mass distributions in $D^+\to K^+K^-\pi^+\pi^0$ decays
Experiment: BESIII (BEPC)
Inspire ID: 1808166
Status: VALIDATED NOHEPDATA
Authors:
  • Peter Richardson
References:
  • Phys.Rev.D 102 (2020) 5, 052006
Beams: * *
Beam energies: ANY
Run details:
  • Any process producting D+ mesons, originally psi(3770) decay

Measurement of the mass distributions in $D^+\to K^+K^-\pi^+\pi^0$ decays by the BESIII collaboration. The data were read from the plots in the paper, and then the backgrounds given subtracted, and therefore for some points the error bars are the size of the point. Also resolution and efficiencies have not been unfolded.

Source code: BESIII_2020_I1808166.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 D+ -> K+K-pi+pi0
10  class BESIII_2020_I1808166 : public Analysis {
11  public:
12
13    /// Constructor
14    RIVET_DEFAULT_ANALYSIS_CTOR(BESIII_2020_I1808166);
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==411);
24      declare(ufs, "UFS");
25      DecayedParticles DD(ufs);
26      DD.addStable(PID::PI0);
27      DD.addStable(PID::K0S);
28      declare(DD, "DD");
29      // histograms
30      for (unsigned int ix=0; ix<10; ++ix) {
31        book(_h[ix], 1, 1, 1+ix);
32      }
33    }
34
35
36    /// Perform the per-event analysis
37    void analyze(const Event& event) {
38      DecayedParticles DD = apply<DecayedParticles>(event, "DD");
39      // loop over particles
40      for (unsigned int ix=0; ix<DD.decaying().size(); ++ix) {
41      	int sign = DD.decaying()[ix].pid()/DD.decaying()[ix].abspid();
42      	if ( !DD.modeMatches(ix,4,mode) && !DD.modeMatches(ix,4,modeCC)) continue;
43          const Particle & Kp  = DD.decayProducts()[ix].at( sign*321)[0];
44          const Particle & Km  = DD.decayProducts()[ix].at(-sign*321)[0];
45          const Particle & pip = DD.decayProducts()[ix].at( sign*211)[0];
46          const Particle & pi0 = DD.decayProducts()[ix].at(      111)[0];
47          _h[0]->fill((Kp .mom()+Km .mom()).mass());
48          _h[1]->fill((Kp .mom()+pip.mom()).mass());
49          _h[2]->fill((Kp .mom()+pi0.mom()).mass());
50          _h[3]->fill((Km .mom()+pip.mom()).mass());
51          _h[4]->fill((Km .mom()+pi0.mom()).mass());
52          _h[5]->fill((pip.mom()+pi0.mom()).mass());
53          _h[6]->fill((Kp .mom()+Km .mom()+pip.mom()).mass());
54          _h[7]->fill((Kp .mom()+Km .mom()+pi0.mom()).mass());
55          _h[8]->fill((Kp .mom()+pip.mom()+pi0.mom()).mass());
56          _h[9]->fill((Km .mom()+pip.mom()+pi0.mom()).mass());
57      }
58    }
59
60
61    /// Normalise histograms etc., after the run
62    void finalize() {
63      normalize(_h);
64    }
65
66    /// @}
67
68
69    /// @name Histograms
70    /// @{
71    Histo1DPtr _h[10];
72    const map<PdgId,unsigned int> mode   = { {321,1}, {-321,1}, { 211,1}, { 111,1} };
73    const map<PdgId,unsigned int> modeCC = { {321,1}, {-321,1}, {-211,1}, { 111,1} };
74    /// @}
75
76
77  };
78
79
80  RIVET_DECLARE_PLUGIN(BESIII_2020_I1808166);
81
82}