Rivet analyses

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

namespace Rivet {


  /// @brief e+e- > hadrons at 3.67
  class CLEOC_2005_I654529 : public Analysis {
  public:

    /// Constructor
    RIVET_DEFAULT_ANALYSIS_CTOR(CLEOC_2005_I654529);


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

    /// Book histograms and initialise projections before the run
    void init() {
      // projection
      declare(FinalState(), "FS");
      declare(UnstableParticles(), "UFS");
      // histos
      for (unsigned int ix = 0; ix < 14; ++ix) {
        book(_h[ix], 1, 1, 1 + ix);
      }
    }

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

    /// Perform the per-event analysis
    void analyze(const Event& event) {
      // final state particles
      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 && nCount[111] == 1 && nCount[211] == 1 && nCount[-211] == 1) {
        _h[0]->fill("3.67"s);
      }
      // unstable particles
      const UnstableParticles& ufs = apply<UnstableParticles>(event, "UFS");
      // first the omega, rho, phi  and b_10 pi0 final state
      bool matched = false;
      for (const Particle& p :
           ufs.particles(Cuts::pid == 113 || Cuts::pid == 223 || Cuts::pid == 333 || Cuts::pid == 10113)) {
        if (p.children().empty()) continue;
        map<long, int> nRes = nCount;
        int ncount = ntotal;
        findChildren(p, nRes, ncount);
        if (ncount == 1) {
          matched = true;
          for (const auto& val : nRes) {
            if (val.first == 111) {
              if (val.second != 1) {
                matched = false;
                break;
              }
            }
            else if (val.second != 0) {
              matched = false;
              break;
            }
          }
          if (matched) {
            if (p.pid() == 113) {
              _h[1]->fill("3.67"s);
              _h[2]->fill("3.67"s);
            }
            else if (p.pid() == 223)
              _h[4]->fill("3.67"s);
            else if (p.pid() == 333)
              _h[5]->fill("3.67"s);
            else if (p.pid() == 10113) {
              _h[11]->fill("3.67"s);
              _h[12]->fill("3.67"s);
            }
            break;
          }
        }
        else if (p.pid() != 10113) {
          // check for eta
          for (const Particle& p2 : ufs.particles(Cuts::pid == 221)) {
            map<long, int> nResB = nRes;
            int ncountB = ncount;
            findChildren(p2, nResB, ncountB);
            if (ncountB != 0) continue;
            matched = true;
            for (const auto& val : nResB) {
              if (val.second != 0) {
                matched = false;
                break;
              }
            }
            if (matched) {
              if (p.pid() == 113)
                _h[6]->fill("3.67"s);
              else if (p.pid() == 223)
                _h[7]->fill("3.67"s);
              else if (p.pid() == 333)
                _h[8]->fill("3.67"s);
              break;
            }
          }
        }
      }
      if (matched) return;
      // rho+- b1+- pi-+
      for (const Particle& p : ufs.particles(Cuts::abspid == 213 || Cuts::abspid == 10213)) {
        if (p.children().empty()) continue;
        map<long, int> nRes = nCount;
        int ncount = ntotal;
        findChildren(p, nRes, ncount);
        if (ncount != 1) continue;
        int sign = -p.pid() / p.abspid();
        matched = true;
        for (const auto& val : nRes) {
          if (val.first == sign * 211) {
            if (val.second != 1) {
              matched = false;
              break;
            }
          }
          else if (val.second != 0) {
            matched = false;
            break;
          }
        }
        if (matched) {
          if (p.abspid() == 213) {
            _h[1]->fill("3.67"s);
            _h[3]->fill("3.67"s);
          }
          else {
            _h[11]->fill("3.67"s);
            _h[13]->fill("3.67"s);
          }
          break;
        }
      }
      if (matched) return;
      // K* K
      for (const Particle& p : ufs.particles(Cuts::abspid == 313 || Cuts::abspid == 323)) {
        if (p.children().empty()) continue;
        map<long, int> nRes = nCount;
        int ncount = ntotal;
        findChildren(p, nRes, ncount);
        if (ncount != 1) continue;
        int iMeson = 0;
        int iStable = 0;
        for (const auto& val : nRes) {
          if (val.second == 1) {
            iStable += 1;
            iMeson = val.first;
          }
          else if (val.second != 0) {
            matched = false;
            break;
          }
        }
        if (iStable == 1) {
          if (p.abspid() == 313 || (iMeson == 310 || iMeson == 130)) {
            _h[9]->fill("3.67"s);
            break;
          }
          else if (p.abspid() == 323 and abs(iMeson) == 321 && p.pid() * iMeson < 0) {
            _h[10]->fill("3.67"s);
            break;
          }
          matched = false;
        }
        else {
          matched = false;
        }
      }
    }


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

    /// @}


    /// @name Histograms
    /// @{
    BinnedHistoPtr<string> _h[14];
    /// @}
  };


  RIVET_DECLARE_PLUGIN(CLEOC_2005_I654529);
}