Rivet analyses

title: CLEO_2008_I791716

Dalitz plot analysis of $D^+\to K^+K^-\pi^+$

Experiment: CLEO (CESR)

Inspire ID: 791716

Status: VALIDATED NOHEPDATA

Authors: - Peter Richardson

References: - Phys.Rev.D 78 (2008) 072003

Beams: * *

Beam energies: ANY

Run details: - Any process producing D0

Kinematic distributions in the decay $D^+\to \to K^+K^-\pi^+$. Resolution/acceptance effects have been not unfolded. Given the agreement with the model in the paper this analysis should only be used for qualitative studies.

Source code:CLEO_2008_I791716.cc

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

include "Rivet/Analysis.hh"

include "Rivet/Projections/DecayedParticles.hh"

include "Rivet/Projections/UnstableParticles.hh"

namespace Rivet {

/// @brief D+ -> K+K-pi+ class CLEO_2008_I791716 : public Analysis { public:

/// Constructor
RIVET_DEFAULT_ANALYSIS_CTOR(CLEO_2008_I791716);


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

/// Book histograms and initialise projections before the run
void init() {
  // Initialise and register projections
  UnstableParticles ufs = UnstableParticles(Cuts::abspid == 411);
  declare(ufs, "UFS");
  DecayedParticles DP(ufs);
  DP.addStable(PID::PI0);
  DP.addStable(PID::K0S);
  DP.addStable(PID::ETA);
  DP.addStable(PID::ETAPRIME);
  declare(DP, "DP");
  // histos
  book(_h_Kppi, 1, 1, 1);
  book(_h_Kmpi, 1, 1, 2);
  book(_h_KK, 1, 1, 3);
  book(_dalitz, "dalitz", 50, 0., 2., 50, 0.9, 3.1);
}

/// Perform the per-event analysis
void analyze(const Event& event) {
  static const map<PdgId, unsigned int>& mode = {{321, 1}, {-321, 1}, {211, 1}};
  static const map<PdgId, unsigned int>& modeCC = {{321, 1}, {-321, 1}, {-211, 1}};
  DecayedParticles DP = apply<DecayedParticles>(event, "DP");
  // loop over particles
  for (unsigned int ix = 0; ix < DP.decaying().size(); ++ix) {
    int sign = 1;
    if (DP.decaying()[ix].pid() > 0 && DP.modeMatches(ix, 3, mode)) {
      sign = 1;
    }
    else if (DP.decaying()[ix].pid() < 0 && DP.modeMatches(ix, 3, modeCC)) {
      sign = -1;
    }
    else
      continue;
    const Particles& Kp = DP.decayProducts()[ix].at(sign * 321);
    const Particles& Km = DP.decayProducts()[ix].at(-sign * 321);
    const Particles& pip = DP.decayProducts()[ix].at(sign * 211);
    double mminus = (Km[0].momentum() + pip[0].momentum()).mass2();
    double mplus = (Kp[0].momentum() + pip[0].momentum()).mass2();
    double mKK = (Kp[0].momentum() + Km[0].momentum()).mass2();
    _h_Kppi->fill(mplus);
    _h_Kmpi->fill(mminus);
    _h_KK->fill(mKK);
    _dalitz->fill(mminus, mKK);
  }
}


/// Normalise histograms etc., after the run
void finalize() {
  normalize(_h_Kppi);
  normalize(_h_Kmpi);
  normalize(_h_KK);
  normalize(_dalitz);
}

/// @}


/// @name Histograms
/// @{
Histo1DPtr _h_Kppi, _h_Kmpi, _h_KK;
Histo2DPtr _dalitz;
/// @}

};

RIVET_DECLARE_PLUGIN(CLEO_2008_I791716);

} ```