Rivet analyses

Mass distributions in B⁰ → K⁺K⁻K_S⁰, B⁺ → K⁺K⁻K⁺ and B⁺ → K_S⁰K_S⁰K⁺

Experiment: BABAR (PEP-II)

Inspire ID: 1086537

Status: VALIDATED NOHEPDATA

Authors: - Peter Richardson

References: - Phys.Rev.D 85 (2012) 112010

Beams: * *

Beam energies: ANY

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

Mass distributions in B⁰ → K⁺K⁻K_S⁰, B⁺ → K⁺K⁻K⁺ and B⁺ → K_S⁰K_S⁰K⁺. The data were read from the plots in the paper.

Source code:`BABAR_2012_I1086537.cc`

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

namespace Rivet {


  /// @brief B -> K K K decays
  class BABAR_2012_I1086537 : public Analysis {
  public:

    /// Constructor
    RIVET_DEFAULT_ANALYSIS_CTOR(BABAR_2012_I1086537);


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

    /// Book histograms and initialise projections before the run
    void init() {
      // projections
      UnstableParticles ufs = UnstableParticles(Cuts::abspid==511 or Cuts::abspid==521);
      declare(ufs, "UFS");
      DecayedParticles BB(ufs);
      BB.addStable(310);
      declare(BB, "BB");
      // histograms
      for(unsigned int ix=0;ix<3;++ix)
    for(unsigned int iy=0;iy<3;++iy)
      book(_h_aver[ix][iy],1+2*ix,1,1+iy);
      for(unsigned int ix=0;ix<2;++ix) {
    book(_h_charge2[ix],4,1,1+ix);
    for(unsigned int iy=0;iy<2;++iy)
      book(_h_charge1[ix][iy],2,1+iy,1+ix);
      }
    }


    /// Perform the per-event analysis
    void analyze(const Event& event) {
      static const map<PdgId,unsigned int> & mode1   = { { 321,2},{-321,1}};
      static const map<PdgId,unsigned int> & mode1CC = { { 321,1},{-321,2}};
      static const map<PdgId,unsigned int> & mode2   = { { 310,2},{ 321,1}};
      static const map<PdgId,unsigned int> & mode2CC = { { 310,2},{-321,1}};
      static const map<PdgId,unsigned int> & mode3   = { { 310,1},{ 321,1} ,{-321,1}};
      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 if (BB.modeMatches(ix,3,mode3)) {
      imode=2;
      if(BB.decaying()[ix].pid()<0) sign=-1;
    }
        else
          continue;
    // B+ -> K+ K+ K-
    if(imode==0) {
      const Particles & Kp = BB.decayProducts()[ix].at( sign*321);
      const Particle  & Km = BB.decayProducts()[ix].at(-sign*321)[0];
      double mKpKm[2];
      for(unsigned int ix=0;ix<2;++ix)
        mKpKm[ix] = (Kp[ix].momentum()+Km.momentum()).mass();
      if(mKpKm[0]>mKpKm[1]) swap(mKpKm[0],mKpKm[1]);
      _h_aver[0][0]->fill(mKpKm[0]);
      _h_aver[0][1]->fill(mKpKm[1]);
      _h_aver[0][2]->fill((Kp[0].momentum()+Kp[1].momentum()).mass());
      if(BB.decaying()[ix].pid()>0) {
        for(unsigned int ix=0;ix<2;++ix) _h_charge1[0][ix]->fill(mKpKm[0]);
      }
      else {
        for(unsigned int ix=0;ix<2;++ix) _h_charge1[1][ix]->fill(mKpKm[0]);
      }
    }
    // B+ -> KS0 KS0 K+
    else if(imode==1) {
      const Particles & K0 = BB.decayProducts()[ix].at( 310);
      const Particle  & Kp = BB.decayProducts()[ix].at( sign*321)[0];
      double mK0K0 = (K0[0].momentum()+K0[1].momentum()).mass();
      _h_aver[1][0]->fill(mK0K0);
      double mKpK0[2];
      for(unsigned int ix=0;ix<2;++ix)
        mKpK0[ix] = (K0[ix].momentum()+Kp.momentum()).mass();
      if(mKpK0[0]>mKpK0[1]) swap(mKpK0[0],mKpK0[1]);
      _h_aver[1][1]->fill(mKpK0[1]);
      _h_aver[1][2]->fill(mKpK0[0]);
      if(BB.decaying()[ix].pid()>0) {
        _h_charge2[0]->fill(mK0K0);
      }
      else {
        _h_charge2[1]->fill(mK0K0);
      }
    }
    // B0 -> KS0 K+ K-
    else if(imode==2) {
      const Particle & K0 = BB.decayProducts()[ix].at(      310)[0];
      const Particle & Kp = BB.decayProducts()[ix].at( sign*321)[0];
      const Particle & Km = BB.decayProducts()[ix].at(-sign*321)[0];
      _h_aver[2][0]->fill((Kp.momentum()+Km.momentum()).mass());
      _h_aver[2][1]->fill((K0.momentum()+Km.momentum()).mass());
      _h_aver[2][2]->fill((K0.momentum()+Kp.momentum()).mass());
    }
      }
    }


    /// Normalise histograms etc., after the run
    void finalize() {
      for(unsigned int ix=0;ix<3;++ix)
    for(unsigned int iy=0;iy<3;++iy)
      normalize(_h_aver[ix][iy],1.,false);
      for(unsigned int ix=0;ix<2;++ix) {
    normalize(_h_charge2[ix],1.,false);
    for(unsigned int iy=0;iy<2;++iy)
      normalize(_h_charge1[ix][iy],1.,false);
      }
    }

    /// @}


    /// @name Histograms
    /// @{
    Histo1DPtr _h_aver[3][3];
    Histo1DPtr _h_charge1[2][2];
    Histo1DPtr _h_charge2[2];
    /// @}


  };


  RIVET_DECLARE_PLUGIN(BABAR_2012_I1086537);

}

Rivet analyses

Mass distributions in B0 → K+K−KS0, B+ → K+K−K+ and B+ → KS0KS0K+

Source code:BABAR_2012_I1086537.cc

Mass distributions in B⁰ → K⁺K⁻K_S⁰, B⁺ → K⁺K⁻K⁺ and B⁺ → K_S⁰K_S⁰K⁺

Source code:`BABAR_2012_I1086537.cc`