Rivet analyses

Cross section for e+e− → KS0K±π∓ with π0, η between threshold and 4 GeV

Experiment: BABAR (PEP-II)

Inspire ID: 1591716

Status: VALIDATED NOHEPDATA

Authors: - Peter Richardson

References: - Phys.Rev. D95 (2017) no.9, 092005

Beams: e+ e-

Beam energies: (0.8, 0.8); (0.8, 0.8); (0.8, 0.8); (0.8, 0.8); (0.8, 0.8); (0.8, 0.8); (0.8, 0.8); (0.8, 0.8); (0.8, 0.8); (0.8, 0.8); (0.9, 0.9); (0.9, 0.9); (0.9, 0.9); (0.9, 0.9); (0.9, 0.9); (0.9, 0.9); (0.9, 0.9); (0.9, 0.9); (0.9, 0.9); (0.9, 0.9); (1.0, 1.0); (1.0, 1.0); (1.0, 1.0); (1.0, 1.0); (1.0, 1.0); (1.0, 1.0); (1.0, 1.0); (1.0, 1.0); (1.0, 1.0); (1.0, 1.0); (1.1, 1.1); (1.1, 1.1); (1.1, 1.1); (1.1, 1.1); (1.1, 1.1); (1.1, 1.1); (1.1, 1.1); (1.1, 1.1); (1.1, 1.1); (1.1, 1.1); (1.2, 1.2); (1.2, 1.2); (1.2, 1.2); (1.2, 1.2); (1.2, 1.2); (1.2, 1.2); (1.2, 1.2); (1.2, 1.2); (1.2, 1.2); (1.2, 1.2); (1.3, 1.3); (1.3, 1.3); (1.3, 1.3); (1.3, 1.3); (1.3, 1.3); (1.3, 1.3); (1.3, 1.3); (1.3, 1.3); (1.3, 1.3); (1.3, 1.3); (1.4, 1.4); (1.4, 1.4); (1.4, 1.4); (1.4, 1.4); (1.4, 1.4); (1.4, 1.4); (1.4, 1.4); (1.4, 1.4); (1.4, 1.4); (1.4, 1.4); (1.5, 1.5); (1.5, 1.5); (1.5, 1.5); (1.5, 1.5); (1.5, 1.5); (1.5, 1.5); (1.5, 1.5); (1.5, 1.5); (1.5, 1.5); (1.5, 1.5); (1.6, 1.6); (1.6, 1.6); (1.6, 1.6); (1.6, 1.6); (1.6, 1.6); (1.6, 1.6); (1.6, 1.6); (1.6, 1.6); (1.6, 1.6); (1.6, 1.6); (1.7, 1.7); (1.7, 1.7); (1.7, 1.7); (1.7, 1.7); (1.7, 1.7); (1.7, 1.7); (1.7, 1.7); (1.7, 1.7); (1.7, 1.7); (1.7, 1.7); (1.8, 1.8); (1.8, 1.8); (1.8, 1.8); (1.8, 1.8); (1.8, 1.8); (1.9, 1.9); (1.9, 1.9); (1.9, 1.9); (1.9, 1.9); (1.9, 1.9); (1.9, 1.9); (1.9, 1.9); (1.9, 1.9); (1.9, 1.9); (1.9, 1.9); (1.8, 1.8); (1.8, 1.8); (1.8, 1.8); (1.8, 1.8); (1.8, 1.8); (2.0, 2.0); (2.0, 2.0); (2.0, 2.0); (2.0, 2.0); (2.0, 2.0)GeV

Run details: - e+e- to hadrons

Cross section for e+e− → KS0K±π∓ with π0, η between threshold and 4 GeV using radiative events.

Source code:BABAR_2017_I1591716.cc

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

namespace Rivet {


  /// @brief e+e- -> K_S0K+-pi-+ with pi0, eta
  class BABAR_2017_I1591716 : public Analysis {
  public:

    /// Constructor
    RIVET_DEFAULT_ANALYSIS_CTOR(BABAR_2017_I1591716);


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

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

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

      for (size_t ix = 0; ix < 2; ++ix) {
        book(_sigma[ix], 1 + ix, 1, 1);
        for (const string& en : _sigma[0].binning().edges<0>()) {
          const double eval = std::stod(en) * GeV;
          if (isCompatibleWithSqrtS(eval)) {
            _sqs = en;
            break;
          }
        }
      }
      raiseBeamErrorIf(_sqs.empty());
    }

    void findChildren(const Particle& p, map<long, int>& nRes, int& ncount) {
      for (const Particle& child : p.children()) {
        if (child.children().empty()) {
          nRes[child.pid()] -= 1;
          --ncount;
        }
        else {
          findChildren(child, nRes, ncount);
        }
      }
    }


    /// Perform the per-event analysis
    void analyze(const Event& event) {
      const FinalState& fs = apply<FinalState>(event, "FS");
      map<long, int> nCount;
      int ntotal(0);
      for (const Particle& p : fs.particles()) {
        nCount[p.pid()] += 1;
        ++ntotal;
      }
      // stable histos
      if (ntotal == 4 && nCount[310] == 1 && nCount[111] == 1
          && ((nCount[321] == 1 && nCount[-211] == 1) || (nCount[-321] == 1 && nCount[211] == 1))) {
        _sigma[0]->fill(_sqs);
      }

      // unstable particles
      const FinalState& ufs = apply<FinalState>(event, "UFS");
      for (const Particle& p : ufs.particles()) {
        if (p.children().empty()) continue;
        if (p.pid() != 221) continue;
        map<long, int> nRes = nCount;
        int ncount = ntotal;
        findChildren(p, nRes, ncount);
        bool matched = true;
        if (p.pid() == 221 && ncount == 3) {
          for (const auto& val : nRes) {
            if (val.first == 310 || val.first == 111) {
              if (val.second != 1) {
                matched = false;
                break;
              }
            }
            else if (abs(val.first) == 321 || abs(val.first) == 211)
              continue;
            else if (val.second != 0) {
              matched = false;
              break;
            }
          }
          if (matched) {
            if ((nRes[321] == 1 && nRes[-211] == 1 && nRes[-321] == 0 && nRes[211] == 0)
                || (nRes[321] == 0 && nRes[-211] == 0 && nRes[-321] == 1 && nRes[211] == 1)) {
              _sigma[1]->fill(_sqs);
            }
          }
        }
      }
    }


    /// Normalise histograms etc., after the run
    void finalize() {
      scale(_sigma, crossSection() / sumOfWeights() / nanobarn);
    }

    /// @}


    /// @name Histograms
    /// @{
    BinnedHistoPtr<string> _sigma[2];
    string _sqs = "";
    /// @}
  };


  RIVET_DECLARE_PLUGIN(BABAR_2017_I1591716);


}