Rivet analyses referenceBESIII_2019_I1722111$\psi(2S)\to p \bar{p}\phi$Experiment: BESIII (BEPC) Inspire ID: 1722111 Status: VALIDATED NOHEPDATA Authors:
Beam energies: ANY Run details:
Measurement of the mass distributions in the decay $\psi(2S)\to p \bar{p}\phi$. The data were read from the plots in the paper. It is also not clear that any resolution effects have been unfolded. Source code: BESIII_2019_I1722111.cc 1// -*- C++ -*-
2#include "Rivet/Analysis.hh"
3#include "Rivet/Projections/DecayedParticles.hh"
4#include "Rivet/Projections/UnstableParticles.hh"
5namespace Rivet {
6
7
8 /// @brief psi(2S) -> p pbar phi
9 class BESIII_2019_I1722111 : public Analysis {
10 public:
11
12 /// Constructor
13 RIVET_DEFAULT_ANALYSIS_CTOR(BESIII_2019_I1722111);
14
15
16 /// @name Analysis methods
17 /// @{
18
19 /// Book histograms and initialise projections before the run
20 void init() {
21 UnstableParticles ufs = UnstableParticles(Cuts::pid==100443);
22 declare(ufs, "UFS");
23 DecayedParticles psi(ufs);
24 psi.addStable(PID::PI0);
25 psi.addStable(PID::K0S);
26 psi.addStable(PID::ETA);
27 psi.addStable(PID::ETAPRIME);
28 psi.addStable(PID::OMEGA);
29 psi.addStable(PID::PHI);
30 declare(psi, "psi");
31 for(unsigned int ix=0;ix<3;++ix)
32 book(_h[ix],1,1,1+ix);
33 book(_dalitz, "dalitz",50,3.5,8,50,3.5,8);
34 }
35
36
37 /// Perform the per-event analysis
38 void analyze(const Event& event) {
39 static const map<PdgId,unsigned int> & mode = { { 2212,1}, {-2212,1}, { 333,1} };
40 DecayedParticles psi = apply<DecayedParticles>(event, "psi");
41 // loop over particles
42 for(unsigned int ix=0;ix<psi.decaying().size();++ix) {
43 if(!psi.modeMatches(ix,3,mode)) continue;
44 const Particle & phi = psi.decayProducts()[ix].at( 333)[0];
45 const Particle & pp = psi.decayProducts()[ix].at( 2212)[0];
46 const Particle & pbar = psi.decayProducts()[ix].at(-2212)[0];
47 if(phi.mass()<1.005 || phi.mass()>1.035) continue;
48 double mminus = (pbar.momentum()+phi .momentum()).mass2();
49 double mplus = (pp .momentum()+phi .momentum()).mass2();
50 double mneut = (pp .momentum()+pbar.momentum()).mass2();
51 _h[0]->fill(sqrt(mplus ));
52 _h[1]->fill(sqrt(mplus ));
53 _h[2]->fill(sqrt(mneut ));
54 _dalitz->fill(mplus,mminus);
55 }
56 }
57
58
59 /// Normalise histograms etc., after the run
60 void finalize() {
61 for(unsigned int ix=0;ix<3;++ix)
62 normalize(_h[ix]);
63 normalize(_dalitz);
64 }
65
66 /// @}
67
68
69 /// @name Histograms
70 /// @{
71 Histo1DPtr _h[3];
72 Histo2DPtr _dalitz;
73 /// @}
74
75
76 };
77
78
79 RIVET_DECLARE_PLUGIN(BESIII_2019_I1722111);
80
81}
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