Rivet analyses

title: BELLE_2018_I1642436

Mass distributions in $B^-\to\Lambda^+_c\bar{\Lambda}^-_cK^-$

Experiment: BELLE (KEKB)

Inspire ID: 1642436

Status: VALIDATED NOHEPDATA

Authors: - Peter Richardson

References: - Eur.Phys.J.C 78 (2018) 3, 252

Beams: * *

Beam energies: ANY

Run details: - Any process producing B-/B+, originally e+e- at Upsilon(4S)

Mass distributions in $B^-\to\Lambda^+_c\bar{\Lambda}^-_cK^-$. Data read from plots and sidebands given subtracted.

Source code:BELLE_2018_I1642436.cc

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

include "Rivet/Analysis.hh"

include "Rivet/Projections/DecayedParticles.hh"

include "Rivet/Projections/UnstableParticles.hh"

namespace Rivet {

/// @brief B- -> Lambda_c+ Lambdabar_c- K- class BELLE_2018_I1642436 : public Analysis { public:

/// Constructor
RIVET_DEFAULT_ANALYSIS_CTOR(BELLE_2018_I1642436);


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

/// Book histograms and initialise projections before the run
void init() {
  UnstableParticles ufs = UnstableParticles(Cuts::abspid == 521);
  declare(ufs, "UFS");
  DecayedParticles BP(ufs);
  BP.addStable(4122);
  BP.addStable(-4122);
  declare(BP, "BP");
  // histos
  for (unsigned int ix = 0; ix < 2; ++ix) book(_h[ix], 1 + ix, 1, 1);
}


/// Perform the per-event analysis
void analyze(const Event& event) {
  static const map<PdgId, unsigned int>& mode = {{4122, 1}, {-4122, 1}, {-321, 1}};
  static const map<PdgId, unsigned int>& modeCC = {{4122, 1}, {-4122, 1}, {321, 1}};
  DecayedParticles BP = apply<DecayedParticles>(event, "BP");
  // loop over particles
  for (unsigned int ix = 0; ix < BP.decaying().size(); ++ix) {
    int sign = 1;
    if (BP.decaying()[ix].pid() < 0 && BP.modeMatches(ix, 3, mode)) {
      sign = 1;
    }
    else if (BP.decaying()[ix].pid() > 0 && BP.modeMatches(ix, 3, modeCC)) {
      sign = -1;
    }
    else
      continue;
    const Particle& LamC = BP.decayProducts()[ix].at(sign * 4122)[0];
    const Particle& LamCBar = BP.decayProducts()[ix].at(-sign * 4122)[0];
    const Particle& Km = BP.decayProducts()[ix].at(-sign * 321)[0];
    _h[0]->fill((LamC.momentum() + Km.momentum()).mass());
    _h[1]->fill((LamC.momentum() + LamCBar.momentum()).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_2018_I1642436);

} ```