Rivet analyses

title: CLEO_2006_I691720

Cross section for light hadron production at 3.671 and 3.773 GeV

Experiment: CLEO (CESR)

Inspire ID: 691720

Status: VALIDATED

Authors: - Peter Richardson

References: - Phys.Rev. D73 (2006) 012002, 2006

Beams: e+ e-

Beam energies: (1.8, 1.8); (1.9, 1.9)GeV

Run details: - e+e- to hadrons

Cross section for $e^+e^-\to \pi^+\pi^-\pi^0$, $\rho^0\pi^0$, $\rho^\pm\pi^\mp$, $\omega\pi^0$, $\rho^0\eta$, $\omega\eta$, $\phi\eta$, $\rho^0\eta^\prime$, $\omega\eta^\prime$, $\phi\eta^\prime$, $K^{0}\bar{K}^{0}$, $K^{*\pm} K^\mp$, $b_1^0\pi^0$, $b_1^\pm\pi^\mp$ at 3.671 and 3.773 GeV.

Source code:CLEO_2006_I691720.cc

```c++ // -- C++ --

include "Rivet/Analysis.hh"

include "Rivet/Projections/FastJets.hh"

include "Rivet/Projections/UnstableParticles.hh"

namespace Rivet {

/// @brief e+ e- -> hadrons class CLEO_2006_I691720 : public Analysis { public:

/// Constructor
RIVET_DEFAULT_ANALYSIS_CTOR(CLEO_2006_I691720);


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

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

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

  // Book histograms
  for (int ix = 1; ix < 18; ++ix) {
    if (ix == 6 || ix == 16) continue;
    book(_nMeson[ix], 1, 1, ix);
  }
  for (const string& en : _nMeson[1].binning().edges<0>()) {
    double eval = stod(en) * GeV;
    if (isCompatibleWithSqrtS(eval)) {
      _sqs = en;
      break;
    }
  }
  raiseBeamErrorIf(_sqs.empty());
}

void findChildren(const Particle& p, map<long, int>& nRes, int& ncount) const {
  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;
  }
  if (ntotal == 3) {
    if (nCount[211] == 1 && nCount[-211] == 1 && nCount[111] == 1) _nMeson[1]->fill(_sqs);
  }
  const FinalState& ufs = apply<FinalState>(event, "UFS");
  for (size_t ix = 0; ix < ufs.particles().size(); ++ix) {
    const Particle& p1 = ufs.particles()[ix];
    if (p1.children().empty()) continue;
    if (p1.pid() != 113 && abs(p1.pid()) != 313) continue;
    map<long, int> nRes = nCount;
    int ncount = ntotal;
    findChildren(p1, nRes, ncount);
    if (p1.pid() == 113 || p1.pid() == 223 || p1.pid() == 10113) {
      if (ncount != 1) continue;
      bool matched = true;
      for (const auto& val : nRes) {
        if (abs(val.first) == 111 && val.second != 1) {
          matched = false;
          break;
        }
        else if (val.second != 0) {
          matched = false;
          break;
        }
      }
      if (matched) {
        if (p1.pid() == 113) {
          _nMeson[2]->fill(_sqs);
          _nMeson[3]->fill(_sqs);
        }
        else if (p1.pid() == 223) {
          _nMeson[5]->fill(_sqs);
        }
        else if (p1.pid() == 10113) {
          _nMeson[15]->fill(_sqs);
        }
      }
    }
    else if (p1.pid() == abs(113) || abs(p1.pid()) == 10113) {
      if (ncount != 1) continue;
      bool matched = true;
      int ipi = p1.pid() > 0 ? -211 : 211;
      for (const auto& val : nRes) {
        if (abs(val.first) == ipi && val.second != 1) {
          matched = false;
          break;
        }
        else if (val.second != 0) {
          matched = false;
          break;
        }
      }
      if (matched) {
        if (p1.pid() == abs(113)) {
          _nMeson[2]->fill(_sqs);
          _nMeson[4]->fill(_sqs);
        }
        else {
          _nMeson[15]->fill(_sqs);
          _nMeson[17]->fill(_sqs);
        }
      }
    }
    else if (p1.pid() == 323) {
      if (ncount != 1) continue;
      bool matched = true;
      int iK = p1.pid() == 323 ? -321 : 321;
      for (const auto& val : nRes) {
        if (abs(val.first) == iK && val.second != 1) {
          matched = false;
          break;
        }
        else if (val.second != 0) {
          matched = false;
          break;
        }
      }
      if (matched) {
        if (_sqs == "3.671"s) _nMeson[14]->fill(_sqs);
      }
    }
    // second unstable particle
    if (p1.abspid() != 313 && p1.pid() != 113 && p1.pid() != 223 && p1.pid() != 333 && p1.pid() != 221
        && p1.pid() != 331)
      continue;
    for (size_t iy = ix + 1; iy < ufs.particles().size(); ++iy) {
      const Particle& p2 = ufs.particles()[iy];
      map<long, int> nRes2 = nRes;
      int ncount2 = ncount;
      findChildren(p2, nRes2, ncount2);
      if (ncount != 0) continue;
      bool matched = true;
      for (const auto& val : nRes2) {
        if (val.second != 0) {
          matched = false;
          break;
        }
      }
      if (!matched) continue;
      if ((p1.pid() == 113 && p2.pid() == 221) || (p2.pid() == 113 && p1.pid() == 221)) {
        _nMeson[7]->fill(_sqs);
      }
      else if ((p1.pid() == 223 && p2.pid() == 221) || (p2.pid() == 223 && p1.pid() == 221)) {
        _nMeson[8]->fill(_sqs);
      }
      else if ((p1.pid() == 333 && p2.pid() == 221) || (p2.pid() == 333 && p1.pid() == 221)) {
        _nMeson[9]->fill(_sqs);
      }
      else if ((p1.pid() == 113 && p2.pid() == 331) || (p2.pid() == 113 && p1.pid() == 331)) {
        _nMeson[10]->fill(_sqs);
      }
      else if ((p1.pid() == 223 && p2.pid() == 331) || (p2.pid() == 223 && p1.pid() == 331)) {
        if (_sqs == "3.773"s) _nMeson[11]->fill(_sqs);
      }
      else if ((p1.pid() == 333 && p2.pid() == 331) || (p2.pid() == 333 && p1.pid() == 331)) {
        if (_sqs == "3.773"s) _nMeson[12]->fill(_sqs);
      }
      else if ((p1.pid() == 313 && p2.pid() == -313) || (p2.pid() == 313 && p1.pid() == -313)) {
        _nMeson[13]->fill(_sqs);
      }
    }
  }
}


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

/// @}


/// @name Histograms
/// @{
map<int, BinnedHistoPtr<string>> _nMeson;
string _sqs = "";
/// @}

};

RIVET_DECLARE_PLUGIN(CLEO_2006_I691720);

} ```