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BABAR_2015_I1308513

$J/\psi\phi$ mass spectrum in $B^{+,0}\to J/\psi \phi K^{+,0}$
Experiment: BABAR (PEP-II)
Inspire ID: 1308513
Status: VALIDATED NOHEPDATA
Authors:
  • Peter Richardson
References:
  • Phys.Rev.D 91 (2015) 1, 012003
Beams: * *
Beam energies: ANY
Run details:
  • Any process producing equal rates of B+ and B0 mesons, originally e+e- at Upsilon(4S)

$J/\psi\phi$ mass spectrum in $B^{+,0}\to J/\psi \phi K^{+,0}$. Only the final background subtracted, efficiency corrected distribution averaged over $B^+$ and $B^0$ is implemented.

Source code: BABAR_2015_I1308513.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 B -> J/psi phi K
10  class BABAR_2015_I1308513 : public Analysis {
11  public:
12
13    /// Constructor
14    RIVET_DEFAULT_ANALYSIS_CTOR(BABAR_2015_I1308513);
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						Cuts::abspid==521);
25      declare(ufs, "UFS");
26      DecayedParticles BB(ufs);
27      BB.addStable(310);
28      BB.addStable(333);
29      BB.addStable(443);
30      declare(BB, "BB");
31      // histo
32      book(_h,1,1,1);
33    }
34
35
36    /// Perform the per-event analysis
37    void analyze(const Event& event) {
38      static const map<PdgId,unsigned int> & mode1   = { { 443,1},{ 333,1}, { 321,1}};
39      static const map<PdgId,unsigned int> & mode1CC = { { 443,1},{ 333,1}, {-321,1}};
40      static const map<PdgId,unsigned int> & mode2   = { { 443,1},{ 333,1}, { 130,1}};
41      static const map<PdgId,unsigned int> & mode2CC = { { 443,1},{ 333,1}, { 310,1}};
42      DecayedParticles BB = apply<DecayedParticles>(event, "BB");
43      // loop over particles
44      for(unsigned int ix=0;ix<BB.decaying().size();++ix) {
45      	if (BB.modeMatches(ix,3,mode1) ||
46	    BB.modeMatches(ix,3,mode1CC) ||
47	    BB.modeMatches(ix,3,mode2) ||
48	    BB.modeMatches(ix,3,mode2CC)) {
49	  const Particle & phi = BB.decayProducts()[ix].at(333)[0];
50	  const Particle & psi = BB.decayProducts()[ix].at(443)[0];
51	  _h->fill((phi.momentum()+psi.momentum()).mass());
52	}
53      }
54    }
55
56
57    /// Normalise histograms etc., after the run
58    void finalize() {
59      normalize(_h,1.,false);
60    }
61
62    /// @}
63
64
65    /// @name Histograms
66    /// @{
67    Histo1DPtr _h;
68    /// @}
69
70
71  };
72
73
74  RIVET_DECLARE_PLUGIN(BABAR_2015_I1308513);
75
76}