Rivet analyses

Mass distributions in B̄⁰ → K⁻π⁺ψ(2S) and B⁺ → K_S⁰π⁺ψ(2S)

Experiment: BELLE (KEKB)

Inspire ID: 820737

Status: VALIDATED NOHEPDATA

Authors: - Peter Richardson

References: - Phys.Rev.D 80 (2009) 031104

Beams: * *

Beam energies: ANY

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

Measurement of mass distributions in B̄⁰ → K⁻π⁺ψ(2S) and B⁺ → K_S⁰π⁺ψ(2S) decays, only the average of the two modes is measured. The data were read from the plots in the paper and may not be corrected for efficiency/acceptance, however the backgrounds given in the paper have been subtracted.

Source code:`BELLE_2009_I820737.cc`

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

namespace Rivet {


  /// @brief  B-> K pi psi(2S)
  class BELLE_2009_I820737 : public Analysis {
  public:

    /// Constructor
    RIVET_DEFAULT_ANALYSIS_CTOR(BELLE_2009_I820737);


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

    /// Book histograms and initialise projections before the run
    void init() {
      // Initialise and register projections
      UnstableParticles ufs = UnstableParticles(Cuts::abspid==511 || Cuts::abspid==521);
      declare(ufs, "UFS");
      DecayedParticles BB(ufs);
      BB.addStable(310);
      BB.addStable(100443);
      declare(BB, "BB");
      // histograms
      const vector<double> bins1 = {0,sqr(0.796),sqr(0.996),sqr(1.332),sqr(1.532),3};
      const vector<double> bins2 = {0,19.0,20.5,23};
      book(_h_piPsi, bins1, {"d01-x01-y01","d01-x01-y02","d01-x01-y03","d01-x01-y04","d01-x01-y05"});
      book(_h_Kpi, bins2, {"d02-x01-y01","d02-x01-y02","d02-x01-y03"});
      book(_h_veto,3,1,1);
      book(_c,"TMP/nB");
    }


    /// Perform the per-event analysis
    void analyze(const Event& event) {
      static const map<PdgId,unsigned int> & mode1   = { { 321,1},{-211,1}, { 100443,1}};
      static const map<PdgId,unsigned int> & mode1CC = { {-321,1},{ 211,1}, { 100443,1}};
      static const map<PdgId,unsigned int> & mode2   = { { 310,1},{-211,1}, { 100443,1}};
      static const map<PdgId,unsigned int> & mode2CC = { { 310,1},{ 211,1}, { 100443,1}};
      DecayedParticles BB = apply<DecayedParticles>(event, "BB");
      // loop over particles
      for (unsigned int ix=0; ix<BB.decaying().size(); ++ix) {
        int sign = 1,iK(0);
        if (BB.decaying()[ix].pid()>0 && BB.modeMatches(ix,3,mode1)) {
          sign=1; iK = 321;
        }
        else if  (BB.decaying()[ix].pid()<0 && BB.modeMatches(ix,3,mode1CC)) {
          sign=-1; iK=-321;
        }
        else if (BB.decaying()[ix].pid()<0 && BB.modeMatches(ix,3,mode2)) {
          sign=1; iK = 310;
        }
        else if  (BB.decaying()[ix].pid()>0 && BB.modeMatches(ix,3,mode2CC)) {
          sign=-1; iK= 310;
        }
        else {
          continue;
        }
        _c->fill();
        const Particle & Kp  = BB.decayProducts()[ix].at( iK)[0];
        const Particle & pim = BB.decayProducts()[ix].at(-211*sign)[0];
        const Particle & psi = BB.decayProducts()[ix].at( 100443  )[0];
        double m2Kpi  = (Kp .momentum()+pim.momentum()).mass2();
        double m2Psipi= (psi.momentum()+pim.momentum()).mass2();
        _h_piPsi->fill(m2Kpi, m2Psipi);
        _h_Kpi->fill(m2Psipi, m2Kpi);
        if(m2Kpi<sqr(0.796) || (m2Kpi>sqr(0.996)&&m2Kpi<sqr(1.332)) ||
           m2Kpi>sqr(1.532)) _h_veto->fill(m2Psipi);
      }
    }


    /// Normalise histograms etc., after the run
    void finalize() {
      scale(_h_piPsi, 1./ *_c);
      scale(_h_Kpi, 1./ *_c);
      normalize(_h_veto, 1.0, false);
    }

    /// @}


    /// @name Histograms
    /// @{
    Histo1DGroupPtr _h_piPsi, _h_Kpi;
    CounterPtr _c;
    Histo1DPtr _h_veto;
    /// @}


  };


  RIVET_DECLARE_PLUGIN(BELLE_2009_I820737);

}

Rivet analyses

Mass distributions in B̄0 → K−π+ψ(2S) and B+ → KS0π+ψ(2S)

Source code:BELLE_2009_I820737.cc

Mass distributions in B̄⁰ → K⁻π⁺ψ(2S) and B⁺ → K_S⁰π⁺ψ(2S)

Source code:`BELLE_2009_I820737.cc`