Rivet analyses

Inclusive B* cross-section above the Υ(4S)

Experiment: CLEO (CESR)

Inspire ID: 29927

Status: VALIDATED

Authors: - Peter Richardson

References: - Phys.Rev.Lett. 67 (1991) 1692-1695

Beams: e- e+

Beam energies: (5.3, 5.3); (5.3, 5.3); (5.3, 5.3); (5.3, 5.3); (5.3, 5.3); (5.3, 5.3); (5.3, 5.3)GeV

Run details: - e+e- collisions

Measurement of the inclusive cross section for B* production at energies above the Υ(4S) mass.

Source code:CLEO_1991_I29927.cc

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

namespace Rivet {


  class CLEO_1991_I29927 : public Analysis {
  public:

    /// Constructor
    RIVET_DEFAULT_ANALYSIS_CTOR(CLEO_1991_I29927);


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

    /// Book histograms and initialise projections before the run
    void init() {

      // Initialise and register projections
      declare(UnstableParticles(), "UFS");

      // Book histograms
      book(_c_B    , 1, 1, 1);
      book(_c_Bstar, 2, 1, 1);
      for (const string& en : _c_B.binning().edges<0>()) {
        const double eval = stod(en);
        if (isCompatibleWithSqrtS(eval)) {
          _sqs = en; break;
        }
      }
      raiseBeamErrorIf(_sqs.empty());
    }


    /// Perform the per-event analysis
    void analyze(const Event& event) {
      const FinalState& ufs = apply<FinalState>(event, "UFS");
      unsigned int nBstar(0);
      // Get Bottom hadrons
      const Particles bhads = select(ufs.particles(), isBottomHadron);
      // find the Bstars
      for (const Particle& p : bhads) {
        if (p.abspid()==513 || p.abspid()==523) {
          if (!p.hasDescendantWith(Cuts::pid == p.pid())) ++nBstar;
        }
      }
      if (!bhads.empty()) _c_B->fill(_sqs);
      if (nBstar!=0)      _c_Bstar->fill(_sqs,nBstar);
    }


    /// Normalise histograms etc., after the run
    void finalize() {
      const double fact = crossSection()/ sumOfWeights() /picobarn;
      scale(_c_B, fact);
      scale(_c_Bstar, fact);
    }

    /// @}


    /// @name Histograms
    /// @{
    BinnedHistoPtr<string> _c_B, _c_Bstar;
    string _sqs = "";
    /// @}


  };


  RIVET_DECLARE_PLUGIN(CLEO_1991_I29927);


}