Rivet analyses referenceBELLE_2013_I1247463Dalitz plot analysis of $\Upsilon(5S)\to\Upsilon(1,2,3S)\pi^0\pi^0$Experiment: BELLE (KEKB) Inspire ID: 1247463 Status: VALIDATED NOHEPDATA Authors:
Beam energies: ANY Run details:
Measurement of the mass distributions in the decays $\Upsilon(5S)\to\Upsilon(1,2,3S)\pi^0\pi^0$ by BELLE. Source code: BELLE_2013_I1247463.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 Upsilon(5S) -> Upsilon(nS) pi0 pi0
10 class BELLE_2013_I1247463 : public Analysis {
11 public:
12
13 /// Constructor
14 RIVET_DEFAULT_ANALYSIS_CTOR(BELLE_2013_I1247463);
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==9000553);
24 declare(ufs, "UFS");
25 DecayedParticles UPS(ufs);
26 UPS.addStable(PID::PI0);
27 UPS.addStable( 553);
28 UPS.addStable(100553);
29 UPS.addStable(200553);
30 declare(UPS, "UPS");
31 // histograms
32 for(unsigned int ix=0;ix<3;++ix)
33 for(unsigned int iy=0;iy<3;++iy)
34 book(_h[ix][iy],1+ix,1,1+iy);
35 }
36
37
38 /// Perform the per-event analysis
39 void analyze(const Event& event) {
40 // find the Upsilon(5S) decays
41 static const map<PdgId,unsigned int> mode[3] = {{ { 553,1}, { 111,2}},
42 { { 100553,1}, { 111,2}},
43 { { 200553,1}, { 111,2}}};
44 DecayedParticles UPS = apply<DecayedParticles>(event, "UPS");
45 for(unsigned int ix=0;ix<UPS.decaying().size();++ix) {
46 unsigned int imode;
47 for(imode=0;imode<3;++imode) {
48 if(UPS.modeMatches(ix,3,mode[imode])) break;
49 }
50 if(imode>2) continue;
51 const Particles & pi0 = UPS.decayProducts()[ix].at( 111);
52 const Particle & ups = UPS.decayProducts()[ix].at(553+imode*100000)[0];
53 double mUpsPi[2];
54 for(unsigned int iy=0;iy<2;++iy)
55 mUpsPi[iy] = (ups.momentum()+pi0[iy].momentum()).mass();
56 if(mUpsPi[0]<mUpsPi[1]) swap(mUpsPi[0],mUpsPi[1]);
57 _h[imode][0]->fill(mUpsPi[0]);
58 _h[imode][1]->fill((pi0[0].momentum()+pi0[1].momentum()).mass());
59 _h[imode][2]->fill(mUpsPi[1]);
60 }
61 }
62
63
64 /// Normalise histograms etc., after the run
65 void finalize() {
66 for(unsigned int ix=0;ix<3;++ix)
67 for(unsigned int iy=0;iy<3;++iy)
68 normalize(_h[ix][iy],1.,false);
69 }
70
71 /// @}
72
73
74 /// @name Histograms
75 /// @{
76 Histo1DPtr _h[3][3];
77 /// @}
78
79
80 };
81
82
83 RIVET_DECLARE_PLUGIN(BELLE_2013_I1247463);
84
85}
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