Rivet analyses

title: BELLE_2005_I660759

Mass distributions in $\Xi^0_c\to pK^-K^-\pi^+$

Experiment: BELLE (KEKB)

Inspire ID: 660759

Status: VALIDATED NOHEPDATA

Authors: - Peter Richardson

References: - Phys.Lett.B 605 (2005) 237-246

Beams: * *

Beam energies: ANY

Run details: - Any process producing Xic0 mesons

Measurement of the mass distributions in the decay $\Xi^0_c\to pK^-K^-\pi^+$ by BELLE. The data were read from the plots in the paper, and for many points the error bars are the size of the point.

Source code:BELLE_2005_I660759.cc

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

include "Rivet/Analysis.hh"

include "Rivet/Projections/DecayedParticles.hh"

include "Rivet/Projections/UnstableParticles.hh"

namespace Rivet {

/// @brief Xi_c0 -> p K- K- pi+ class BELLE_2005_I660759 : public Analysis { public:

/// Constructor
RIVET_DEFAULT_ANALYSIS_CTOR(BELLE_2005_I660759);


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

/// Book histograms and initialise projections before the run
void init() {
  // Initialise and register projections
  UnstableParticles ufs = UnstableParticles(Cuts::abspid == 4132);
  declare(ufs, "UFS");
  DecayedParticles XIC0(ufs);
  XIC0.addStable(PID::PI0);
  XIC0.addStable(PID::K0S);
  XIC0.addStable(PID::ETA);
  XIC0.addStable(PID::ETAPRIME);
  declare(XIC0, "XIC0");
  // histograms
  book(_h, 1, 1, 1);
}


/// Perform the per-event analysis
void analyze(const Event& event) {
  static const map<PdgId, unsigned int>& mode = {{PID::KMINUS, 2}, {PID::PROTON, 1}, {PID::PIPLUS, 1}};
  static const map<PdgId, unsigned int>& modeCC = {{PID::KPLUS, 2}, {-PID::PROTON, 1}, {PID::PIMINUS, 1}};
  DecayedParticles XIC0 = apply<DecayedParticles>(event, "XIC0");
  // loop over particles
  for (unsigned int ix = 0; ix < XIC0.decaying().size(); ++ix) {
    int sign = 1;
    if (XIC0.decaying()[ix].pid() > 0 && XIC0.modeMatches(ix, 4, mode)) {
      sign = 1;
    }
    else if (XIC0.decaying()[ix].pid() < 0 && XIC0.modeMatches(ix, 4, modeCC)) {
      sign = -1;
    }
    else
      continue;
    const Particle& pip = XIC0.decayProducts()[ix].at(sign * PID::PIPLUS)[0];
    const Particles& Km = XIC0.decayProducts()[ix].at(sign * PID::KMINUS);
    for (unsigned int ix = 0; ix < 2; ++ix) _h->fill((pip.momentum() + Km[ix].momentum()).mass());
  }
}


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

/// @}


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

};

RIVET_DECLARE_PLUGIN(BELLE_2005_I660759);

} ```