Rivet analyses

title: BABAR_2015_I1335269

Mass distributions in the decays $B^0\to D^-D^0K^+$ and $B^+\to\bar{D}^0D^0K^+$

Experiment: BABAR (PEP-II)

Inspire ID: 1335269

Status: VALIDATED NOHEPDATA

Authors: - Peter Richardson

References: - Phys.Rev.D 91 (2015) 5, 052002

Beams: * *

Beam energies: ANY

Run details: - Any process producing B0 and B+, originally Upsilon(4S) decays

Mass distributions in the decays $B^0\to D^-D^0K^+$ and $B^+\to\bar{D}^0D^0K^+$ the data were read from the plots in the paper and the backgrounds from the paper subtracted they may be be correct for efficiency.

Source code:BABAR_2015_I1335269.cc

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

include "Rivet/Analysis.hh"

include "Rivet/Projections/DecayedParticles.hh"

include "Rivet/Projections/UnstableParticles.hh"

namespace Rivet {

/// @brief B -> D D K class BABAR_2015_I1335269 : public Analysis { public:

/// Constructor
RIVET_DEFAULT_ANALYSIS_CTOR(BABAR_2015_I1335269);


/// @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);
  declare(BB, "BB");
  // histograms
  for (unsigned int ix = 0; ix < 2; ++ix) {
    for (unsigned int iy = 0; iy < 3; ++iy) {
      book(_h[ix][iy], 1 + ix, 1, 1 + iy);
    }
  }
}


/// Perform the per-event analysis
void analyze(const Event& event) {
  static const map<PdgId, unsigned int>& mode1 = {{-411, 1}, {421, 1}, {321, 1}};
  static const map<PdgId, unsigned int>& mode1CC = {{411, 1}, {-421, 1}, {-321, 1}};
  static const map<PdgId, unsigned int>& mode2 = {{-421, 1}, {421, 1}, {321, 1}};
  static const map<PdgId, unsigned int>& mode2CC = {{421, 1}, {-421, 1}, {-321, 1}};
  DecayedParticles BB = apply<DecayedParticles>(event, "BB");
  for (unsigned int ix = 0; ix < BB.decaying().size(); ++ix) {
    int sign = 1, imode = 0;
    if (BB.decaying()[ix].pid() > 0 && BB.modeMatches(ix, 3, mode1)) {
      imode = 0;
      sign = 1;
    }
    else if (BB.decaying()[ix].pid() < 0 && BB.modeMatches(ix, 3, mode1CC)) {
      imode = 0;
      sign = -1;
    }
    else if (BB.decaying()[ix].pid() > 0 && BB.modeMatches(ix, 3, mode2)) {
      imode = 1;
      sign = 1;
    }
    else if (BB.decaying()[ix].pid() < 0 && BB.modeMatches(ix, 3, mode2CC)) {
      imode = 1;
      sign = -1;
    }
    else
      continue;
    const Particle& D0 = BB.decayProducts()[ix].at(sign * 421)[0];
    const Particle& Kp = BB.decayProducts()[ix].at(sign * 321)[0];
    int iD = imode == 0 ? 411 : 421;
    const Particle& Dm = BB.decayProducts()[ix].at(-sign * iD)[0];
    _h[imode][0]->fill((D0.momentum() + Dm.momentum()).mass());
    _h[imode][1]->fill((Kp.momentum() + Dm.momentum()).mass());
    _h[imode][2]->fill((Kp.momentum() + D0.momentum()).mass());
  }
}


/// Normalise histograms etc., after the run
void finalize() {
  for (unsigned int ix = 0; ix < 2; ++ix) {
    for (unsigned int iy = 0; iy < 3; ++iy) {
      normalize(_h[ix][iy], 1., false);
    }
  }
}

/// @}


/// @name Histograms
/// @{
Histo1DPtr _h[2][3];
/// @}

};

RIVET_DECLARE_PLUGIN(BABAR_2015_I1335269);

} ```