Rivet analyses

title: BELLE_2023_I2655951

$K^-K^0_S$ mass distribution in $B\to D^{(*)}K^-K^0_S$ decays

Experiment: BELLE (KEKB)

Inspire ID: 2655951

Status: VALIDATED NOHEPDATA

Authors: - Peter Richardson

References: - arXiv: 2305.01321

Beams: * *

Beam energies: ANY

Run details: - Any process producing B mesons, originally Upsilon(4S) decays

Measurement of $K^-K^0_S$ mass distribution in $B\to D^{(*)}K^-K^0_S$ decays. The corrected, background subtracted data was read from the figures in the paper.

Source code:BELLE_2023_I2655951.cc

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

include "Rivet/Analysis.hh"

include "Rivet/Projections/DecayedParticles.hh"

include "Rivet/Projections/UnstableParticles.hh"

namespace Rivet {

/// @brief B -> D(*) K- KS0 class BELLE_2023_I2655951 : public Analysis { public:

/// Constructor
RIVET_DEFAULT_ANALYSIS_CTOR(BELLE_2023_I2655951);


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

/// Book histograms and initialise projections before the run
void init() {
  UnstableParticles ufs = UnstableParticles(Cuts::abspid == 511 or Cuts::abspid == 521);
  declare(ufs, "UFS");
  DecayedParticles BB(ufs);
  BB.addStable(411);
  BB.addStable(-411);
  BB.addStable(421);
  BB.addStable(-421);
  BB.addStable(413);
  BB.addStable(-413);
  BB.addStable(423);
  BB.addStable(-423);
  BB.addStable(310);
  BB.addStable(313);
  BB.addStable(-313);
  declare(BB, "BB");
  for (unsigned int ix = 0; ix < 4; ++ix) {
    book(_h[ix], 1, 1, 1 + ix);
  }
}


/// Perform the per-event analysis
void analyze(const Event& event) {
  static const double mDs = 1.96835;
  static const map<PdgId, unsigned int> modes[4] = {{{-421, 1}, {321, 1}, {310, 1}},
                                                    {{-411, 1}, {321, 1}, {310, 1}},
                                                    {{-423, 1}, {321, 1}, {310, 1}},
                                                    {{-413, 1}, {321, 1}, {310, 1}}};
  static const map<PdgId, unsigned int> modesCC[4] = {{{421, 1}, {-321, 1}, {310, 1}},
                                                      {{411, 1}, {-321, 1}, {310, 1}},
                                                      {{423, 1}, {-321, 1}, {310, 1}},
                                                      {{413, 1}, {-321, 1}, {310, 1}}};
  DecayedParticles BB = apply<DecayedParticles>(event, "BB");
  for (unsigned int ix = 0; ix < BB.decaying().size(); ++ix) {
    int imode = -1;
    for (unsigned int iy = 0; iy < 4; ++iy) {
      if (BB.decaying()[ix].pid() > 0 && BB.modeMatches(ix, 3, modes[iy])) {
        imode = iy;
        break;
      }
      else if (BB.decaying()[ix].pid() < 0 && BB.modeMatches(ix, 3, modesCC[iy])) {
        imode = iy;
        break;
      }
    }
    if (imode < 0) continue;
    int sign = BB.decaying()[ix].pid() / BB.decaying()[ix].abspid();
    const Particle& Km = BB.decayProducts()[ix].at(sign * 321)[0];
    const Particle& K0 = BB.decayProducts()[ix].at(310)[0];
    double mKK = (Km.momentum() + K0.momentum()).mass();
    if (abs(mKK - mDs) < 0.02) continue;
    _h[imode]->fill(mKK);
  }
}


/// Normalise histograms etc., after the run
void finalize() {
  normalize(_h, 1.0, false);
}

/// @}


/// @name Histograms
/// @{
Histo1DPtr _h[4];
/// @}

};

RIVET_DECLARE_PLUGIN(BELLE_2023_I2655951);

} ```