Rivet analyses

title: BELLE_2015_I1326905

Mass distributions in the decays $B^0\to D^-_sK^0_S\pi^+$ and $B^+\to D^-_sK^+K^+$

Experiment: BELLE (KEKB)

Inspire ID: 1326905

Status: VALIDATED NOHEPDATA

Authors: - Peter Richardson

References: - Phys.Rev.D 91 (2015) 3, 032008

Beams: * *

Beam energies: ANY

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

Mass distributions in the decays $B^0\to D^-_sK^0_S\pi^+$ and $B^+\to D^-_sK^+K^+$, the data were read from the plots in the paper and although the backgrounds have been subtracted they may be be correct for efficiency.

Source code:BELLE_2015_I1326905.cc

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

include "Rivet/Analysis.hh"

include "Rivet/Projections/DecayedParticles.hh"

include "Rivet/Projections/UnstableParticles.hh"

namespace Rivet {

/// @brief B0 ->\to Ds- KS0 pi+ and B+ -> Ds- K+ K^+ class BELLE_2015_I1326905 : public Analysis { public:

/// Constructor
RIVET_DEFAULT_ANALYSIS_CTOR(BELLE_2015_I1326905);


/// @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(431);
  BB.addStable(-431);
  BB.addStable(310);
  declare(BB, "BB");
  //histograms
  for (unsigned int ix = 0; ix < 2; ++ix) {
    book(_h[ix], 1, 1, 1 + ix);
  }
}


/// Perform the per-event analysis
void analyze(const Event& event) {
  static const map<PdgId, unsigned int>& mode1 = {{-431, 1}, {310, 1}, {211, 1}};
  static const map<PdgId, unsigned int>& mode1CC = {{431, 1}, {310, 1}, {-211, 1}};
  static const map<PdgId, unsigned int>& mode2 = {{-431, 1}, {321, 2}};
  static const map<PdgId, unsigned int>& mode2CC = {{431, 1}, {-321, 2}};
  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& Ds = BB.decayProducts()[ix].at(-sign * 431)[0];
    FourMomentum pK;
    if (imode == 0) {
      pK = BB.decayProducts()[ix].at(310)[0].momentum();
    }
    else {
      const Particles& Kp = BB.decayProducts()[ix].at(sign * 321);
      pK = Kp[0].momentum().p3().mod() > Kp[1].momentum().p3().mod() ? Kp[1].momentum()
                                                                     : Kp[0].momentum();
    }
    _h[imode]->fill((Ds.momentum() + pK).mass());
  }
}


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

/// @}


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

};

RIVET_DECLARE_PLUGIN(BELLE_2015_I1326905);

} ```