Rivet analyses

title: 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

```c++ // -- C++ --

include "Rivet/Analysis.hh"

include "Rivet/Projections/DecayedParticles.hh"

include "Rivet/Projections/UnstableParticles.hh"

namespace Rivet {

/// @brief B -> J/psi phi K class BABAR_2015_I1308513 : public Analysis { public:

/// Constructor
RIVET_DEFAULT_ANALYSIS_CTOR(BABAR_2015_I1308513);


/// @name Analysis methods
/// @{

/// Book histograms and initialise projections before the run
void init() {
  // Initialise and register projections
  UnstableParticles ufs = UnstableParticles(Cuts::abspid == 511 || Cuts::abspid == 521);
  declare(ufs, "UFS");
  DecayedParticles BB(ufs);
  BB.addStable(310);
  BB.addStable(333);
  BB.addStable(443);
  declare(BB, "BB");
  // histo
  book(_h, 1, 1, 1);
}


/// Perform the per-event analysis
void analyze(const Event& event) {
  static const map<PdgId, unsigned int>& mode1 = {{443, 1}, {333, 1}, {321, 1}};
  static const map<PdgId, unsigned int>& mode1CC = {{443, 1}, {333, 1}, {-321, 1}};
  static const map<PdgId, unsigned int>& mode2 = {{443, 1}, {333, 1}, {130, 1}};
  static const map<PdgId, unsigned int>& mode2CC = {{443, 1}, {333, 1}, {310, 1}};
  DecayedParticles BB = apply<DecayedParticles>(event, "BB");
  // loop over particles
  for (unsigned int ix = 0; ix < BB.decaying().size(); ++ix) {
    if (BB.modeMatches(ix, 3, mode1) || BB.modeMatches(ix, 3, mode1CC) || BB.modeMatches(ix, 3, mode2)
        || BB.modeMatches(ix, 3, mode2CC)) {
      const Particle& phi = BB.decayProducts()[ix].at(333)[0];
      const Particle& psi = BB.decayProducts()[ix].at(443)[0];
      _h->fill((phi.momentum() + psi.momentum()).mass());
    }
  }
}


/// Normalise histograms etc., after the run
void finalize() {
  normalize(_h, 1., false);
}

/// @}


/// @name Histograms
/// @{
Histo1DPtr _h;
/// @}

};

RIVET_DECLARE_PLUGIN(BABAR_2015_I1308513);

} ```