Rivet analyses

Mass distributions in Ξc+ → Σ+K−π+

Experiment: CLEOII (CESR)

Inspire ID: 397787

Status: VALIDATED NOHEPDATA

Authors: - Peter Richardson

References: - Phys.Lett.B 365 (1996) 431-436

Beams: * *

Beam energies: ANY

Run details: - Any process producing Xic+ mesons

Measurement of the mass distributions in the decay Ξc+ → Σ+K−π+ by CLEOII. The data were read from the plots in the paper and may not have been corrected for efficiency/acceptance.

Source code:CLEOII_1996_I397787.cc

// -*- C++ -*-
#include "Rivet/Analysis.hh"
#include "Rivet/Projections/DecayedParticles.hh"
#include "Rivet/Projections/UnstableParticles.hh"

namespace Rivet {


  /// @brief Xi_c+ -> Sigma+ K- pi+
  class CLEOII_1996_I397787 : public Analysis {
  public:

    /// Constructor
    RIVET_DEFAULT_ANALYSIS_CTOR(CLEOII_1996_I397787);


    /// @name Analysis methods
    /// @{
    /// Book histograms and initialise projections before the run
    void init() {
      // Initialise and register projections
      UnstableParticles ufs = UnstableParticles(Cuts::abspid == 4232);
      declare(ufs, "UFS");
      DecayedParticles XICP(ufs);
      XICP.addStable(PID::PI0);
      XICP.addStable(PID::K0S);
      XICP.addStable(PID::ETA);
      XICP.addStable(3222);
      XICP.addStable(-3222);
      declare(XICP, "XICP");
      // 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, 1}, {3222, 1}, {PID::PIPLUS, 1}};
      static const map<PdgId, unsigned int>& modeCC = {{PID::KPLUS, 1}, {-3222, 1}, {PID::PIMINUS, 1}};
      DecayedParticles XICP = apply<DecayedParticles>(event, "XICP");
      // loop over particles
      for (unsigned int ix = 0; ix < XICP.decaying().size(); ++ix) {
        int sign = 1;
        if (XICP.decaying()[ix].pid() > 0 && XICP.modeMatches(ix, 3, mode)) {
          sign = 1;
        }
        else if (XICP.decaying()[ix].pid() < 0 && XICP.modeMatches(ix, 3, modeCC)) {
          sign = -1;
        }
        else
          continue;
        const Particle& pip = XICP.decayProducts()[ix].at(sign * PID::PIPLUS)[0];
        const Particle& Km = XICP.decayProducts()[ix].at(sign * PID::KMINUS)[0];
        _h->fill((pip.momentum() + Km.momentum()).mass());
      }
    }


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

    /// @}


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


  RIVET_DECLARE_PLUGIN(CLEOII_1996_I397787);

}