Rivet analyses referenceMARKIII_1987_I247266Dalitz plot analysis of $D\to K\pi\pi$ decaysExperiment: MARKIII (PEP) Inspire ID: 247266 Status: VALIDATED NOHEPDATA Authors:
Beam energies: ANY Run details:
Measurement of the mass distributions in the decays $D^0\to K^-\pi^+\pi^0$, $D^0\to K^0_S\pi^+\pi^-$, $D^+\to K^0_S\pi^+\pi^0$ and $D^+\to K^-\pi^+\pi^+$. The data were read from the plots in the paper. Resolution/acceptance effects have been not unfolded and given the agreement with the model in the paper this analysis should only be used for qualitative studies. Source code: MARKIII_1987_I247266.cc 1// -*- C++ -*-
2#include "Rivet/Analysis.hh"
3#include "Rivet/Projections/DecayedParticles.hh"
4#include "Rivet/Projections/UnstableParticles.hh"
5
6namespace Rivet {
7
8
9 /// @brief D -> K pi pi dalitz decays
10 class MARKIII_1987_I247266 : public Analysis {
11 public:
12
13 /// Constructor
14 RIVET_DEFAULT_ANALYSIS_CTOR(MARKIII_1987_I247266);
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 or
24 Cuts::abspid==421);
25 declare(ufs, "UFS");
26 DecayedParticles DD(ufs);
27 DD.addStable(PID::PI0);
28 DD.addStable(PID::K0S);
29 declare(DD, "DD");
30
31 // histos
32 book(_h_1_Kmpip,1,1,1);
33 book(_h_1_pipi ,1,1,2);
34 book(_h_1_Kmpi0,1,1,3);
35 book(_dalitz1, "dalitz1",50,0.3,3.2,50,0.,2.);
36
37 book(_h_2_K0pip,2,1,1);
38 book(_h_2_pipi ,2,1,2);
39 book(_h_2_K0pim,2,1,3);
40 book(_dalitz2, "dalitz2",50,0.3,3.2,50,0.,2.);
41
42 book(_h_3_K0pip,3,1,1);
43 book(_h_3_pipi ,3,1,2);
44 book(_h_3_K0pi0,3,1,3);
45 book(_dalitz3, "dalitz3",50,0.3,3.2,50,0.,2.);
46
47 book(_h_4_Kmpip[0],4,1,1);
48 book(_h_4_pipi ,4,1,2);
49 book(_h_4_Kmpip[1],4,1,3);
50 book(_dalitz4, "dalitz4",50,0.3,2.,50,0.,2.);
51
52 }
53
54 /// Perform the per-event analysis
55 void analyze(const Event& event) {
56 static const map<PdgId,unsigned int> & mode1 = { { 211,1}, {-321,1}, {111,1} };
57 static const map<PdgId,unsigned int> & mode1CC = { {-211,1}, { 321,1}, {111,1} };
58 static const map<PdgId,unsigned int> & mode2 = { { 211,1}, {-211,1}, {310,1} };
59 static const map<PdgId,unsigned int> & mode3 = { { 211,1}, { 111,1}, {310,1} };
60 static const map<PdgId,unsigned int> & mode3CC = { {-211,1}, { 111,1}, {310,1} };
61 static const map<PdgId,unsigned int> & mode4 = { { 211,2}, {-321,1} };
62 static const map<PdgId,unsigned int> & mode4CC = { {-211,2}, { 321,1} };
63 DecayedParticles DD = apply<DecayedParticles>(event, "DD");
64 for(unsigned int ix=0;ix<DD.decaying().size();++ix) {
65 int sign = DD.decaying()[ix].pid()/DD.decaying()[ix].abspid();
66 if(DD.decaying()[ix].abspid()==421) {
67 if ( ( DD.decaying()[ix].pid()>0 && DD.modeMatches(ix,3,mode1 )) ||
68 ( DD.decaying()[ix].pid()<0 && DD.modeMatches(ix,3,mode1CC))) {
69 const Particle & pi0 = DD.decayProducts()[ix].at( 111)[0];
70 const Particle & pip = DD.decayProducts()[ix].at( sign*211)[0];
71 const Particle & Km = DD.decayProducts()[ix].at(-sign*321)[0];
72 double mneut = (Km.momentum()+pip.momentum()).mass2();
73 double mminus = (Km.momentum()+pi0.momentum()).mass2();
74 double mpipi = (pip.momentum()+pi0.momentum()).mass2();
75 _h_1_Kmpip->fill(mneut );
76 _h_1_pipi ->fill(mpipi );
77 _h_1_Kmpi0->fill(mminus);
78 _dalitz1 ->fill(mminus,mpipi);
79 }
80 else if ( DD.modeMatches(ix,3,mode2 )) {
81 const Particle & K0 = DD.decayProducts()[ix].at( 310)[0];
82 const Particle & pip = DD.decayProducts()[ix].at( sign*211)[0];
83 const Particle & pim = DD.decayProducts()[ix].at(-sign*211)[0];
84 double mminus = (pim.momentum()+K0.momentum() ).mass2();
85 double mplus = (pip.momentum()+K0.momentum() ).mass2();
86 double mpipi = (pip.momentum()+pim.momentum()).mass2();
87 _h_2_K0pip->fill(mplus);
88 _h_2_K0pim->fill(mminus);
89 _h_2_pipi ->fill(mpipi);
90 _dalitz2 ->fill(mminus,mpipi);
91 }
92 }
93 else if(DD.decaying()[ix].abspid()==411) {
94 if(DD.modeMatches(ix,3,mode3 ) || DD.modeMatches(ix,3,mode3CC)) {
95 const Particle & pi0 = DD.decayProducts()[ix].at( 111)[0];
96 const Particle & K0 = DD.decayProducts()[ix].at( 310)[0];
97 const Particle & pip = DD.decayProducts()[ix].at( sign*211)[0];
98 double mminus = (K0.momentum()+pip.momentum()).mass2();
99 double mplus = (K0.momentum()+pi0.momentum()).mass2();
100 double mpipi = (pip.momentum()+pi0.momentum()).mass2();
101 _h_3_K0pip->fill( mminus);
102 _h_3_pipi ->fill( mpipi );
103 _h_3_K0pi0->fill( mplus );
104 _dalitz3 ->fill(mplus,mpipi);
105 }
106 else if(DD.modeMatches(ix,3,mode4 ) || DD.modeMatches(ix,3,mode4CC)) {
107 const Particles & pip = DD.decayProducts()[ix].at( sign*211);
108 const Particle & Km = DD.decayProducts()[ix].at(-sign*321)[0];
109 double mplus = (Km.momentum() +pip[0].momentum()).mass2();
110 double mminus = (Km.momentum() +pip[1].momentum()).mass2();
111 double mpipi = (pip[0].momentum()+pip[1].momentum()).mass2();
112 if(mplus<mminus) swap(mplus,mminus);
113 _h_4_Kmpip[1]->fill(mminus);
114 _h_4_Kmpip[0]->fill(mplus );
115 _h_4_pipi ->fill( mpipi);
116 _dalitz4 ->fill(mminus,mpipi);
117 }
118 }
119 }
120 }
121
122
123 /// Normalise histograms etc., after the run
124 void finalize() {
125 normalize(_h_1_Kmpip);
126 normalize(_h_1_pipi );
127 normalize(_h_1_Kmpi0);
128 normalize(_dalitz1 );
129
130 normalize(_h_2_K0pip);
131 normalize(_h_2_pipi );
132 normalize(_h_2_K0pim);
133 normalize(_dalitz2 );
134
135 normalize(_h_3_K0pip);
136 normalize(_h_3_pipi );
137 normalize(_h_3_K0pi0);
138 normalize(_dalitz3 );
139
140 normalize(_h_4_Kmpip[0]);
141 normalize(_h_4_pipi );
142 normalize(_h_4_Kmpip[1]);
143 normalize(_dalitz4 );
144 }
145
146 /// @}
147
148
149 /// @name Histograms
150 /// @{
151 Histo1DPtr _h_1_Kmpip, _h_1_pipi, _h_1_Kmpi0;
152 Histo2DPtr _dalitz1;
153 Histo1DPtr _h_2_K0pip, _h_2_pipi, _h_2_K0pim;
154 Histo2DPtr _dalitz2;
155 Histo1DPtr _h_3_K0pip, _h_3_pipi, _h_3_K0pi0;
156 Histo2DPtr _dalitz3;
157 Histo1DPtr _h_4_Kmpip[2], _h_4_pipi;
158 Histo2DPtr _dalitz4;
159 /// @}
160
161
162 };
163
164
165 RIVET_DECLARE_PLUGIN(MARKIII_1987_I247266);
166
167}
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