Rivet analyses referenceBABAR_2011_I897848Mass distributions in $B^0\to K^+\pi^-\pi^0$ decaysExperiment: BABAR (PEP-II) Inspire ID: 897848 Status: VALIDATED NOHEPDATA Authors:
Beam energies: ANY Run details:
Measurements of mass distributions in $B^0\to K^+\pi^-\pi^0$ decays. The data were read from the plots in the paper and the backgrounds given subtracted. Source code: BABAR_2011_I897848.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 B0 -> K+ pi- pi0
10 class BABAR_2011_I897848 : public Analysis {
11 public:
12
13 /// Constructor
14 RIVET_DEFAULT_ANALYSIS_CTOR(BABAR_2011_I897848);
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==511);
24 declare(ufs, "UFS");
25 DecayedParticles B0(ufs);
26 B0.addStable(PID::PI0);
27 declare(B0, "B0");
28 // histograms
29 for(unsigned int ix=0;ix<3;++ix) {
30 for(unsigned int iy=0;iy<2;++iy) {
31 book(_h[ix][iy],1+ix,1,1+iy);
32 }
33 }
34 }
35
36
37 /// Perform the per-event analysis
38 void analyze(const Event& event) {
39 static const map<PdgId,unsigned int> & mode = { { 321,1},{-211,1}, { 111,1}};
40 static const map<PdgId,unsigned int> & modeCC = { {-321,1},{ 211,1}, { 111,1}};
41 DecayedParticles B0 = apply<DecayedParticles>(event, "B0");
42 // loop over particles
43 for(unsigned int ix=0;ix<B0.decaying().size();++ix) {
44 int sign = 1;
45 if (B0.decaying()[ix].pid()>0 && B0.modeMatches(ix,3,mode)) {
46 sign=1;
47 }
48 else if (B0.decaying()[ix].pid()<0 && B0.modeMatches(ix,3,modeCC)) {
49 sign=-1;
50 }
51 else
52 continue;
53 const Particle & Kp = B0.decayProducts()[ix].at( sign*321)[0];
54 const Particle & pim = B0.decayProducts()[ix].at(-sign*211)[0];
55 const Particle & pi0 = B0.decayProducts()[ix].at( 111)[0];
56 double mpipi = (pim.momentum()+pi0.momentum()).mass();
57 _h[0][0]->fill(mpipi);
58 if(mpipi<1.8) _h[0][1]->fill(mpipi);
59 double mKpi = (Kp.momentum()+pi0.momentum()).mass();
60 _h[1][0]->fill(mKpi);
61 if(mKpi<1.8) _h[1][1]->fill(mKpi);
62 mKpi = (Kp.momentum()+pim.momentum()).mass();
63 _h[2][0]->fill(mKpi);
64 if(mKpi<1.8) _h[2][1]->fill(mKpi);
65 }
66 }
67
68
69 /// Normalise histograms etc., after the run
70 void finalize() {
71 for(unsigned int ix=0;ix<3;++ix) {
72 for(unsigned int iy=0;iy<2;++iy) {
73 normalize(_h[ix][iy],1.,false);
74 }
75 }
76 }
77
78 /// @}
79
80
81 /// @name Histograms
82 /// @{
83 Histo1DPtr _h[3][2];
84 /// @}
85
86
87 };
88
89
90 RIVET_DECLARE_PLUGIN(BABAR_2011_I897848);
91
92}
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