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/DecayedParticles.hh"
#include "Rivet/Projections/UnstableParticles.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`