Rivet analyses

title: CLEOII_1995_I397770

Spectrum for $\Xi_c^{*0}$ production at 10.58 GeV

Experiment: CLEOII (CESR)

Inspire ID: 397770

Status: VALIDATED

Authors: - Peter Richardson

References: - Phys.Rev.Lett. 75 (1995) 4364-4368

Beams: e+ e-

Beam energies: (5.3, 5.3)GeV

Run details: - e+e- to hadrons

Spectrum for $\Xi_c^{*0}$ production at 10.58 GeV measured by CLEOII.

Source code:CLEOII_1995_I397770.cc

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

include "Rivet/Analysis.hh"

include "Rivet/Projections/Beam.hh"

include "Rivet/Projections/UnstableParticles.hh"

namespace Rivet {

/// @brief Xi_c*0 spectrum class CLEOII_1995_I397770 : public Analysis { public:

/// Constructor
RIVET_DEFAULT_ANALYSIS_CTOR(CLEOII_1995_I397770);


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

/// Book histograms and initialise projections before the run
void init() {
  // projections
  declare(Beam(), "Beams");
  declare(UnstableParticles(), "UFS");
  // book histos
  book(_h_x, 2, 1, 1);
  book(_r, 3, 1, 1);
  book(_c_xi, "TMP/c_xi");
}

// Check for explicit decay into pdgids
bool isDecay(const Particle& mother, vector<int> ids) {
  if (mother.pid() < 0) {
    for (unsigned int ix = 0; ix < ids.size(); ++ix) ids[ix] *= -1;
  }
  // Trivial check to ignore any other decays but the one in question modulo photons
  const Particles children = mother.children(Cuts::pid != PID::PHOTON);
  if (children.size() != ids.size()) return false;
  // Check for the explicit decay
  return all(ids, [&](int i) { return count(children, hasPID(i)) == 1; });
}

/// Perform the per-event analysis
void analyze(const Event& event) {
  static const int idXi = 4314;
  const ParticlePair& beams = apply<Beam>(event, "Beams").beams();
  const double Emax = (beams.first.p3().mod() + beams.second.p3().mod()) / 2.0;
  const double Pmax = sqrt(sqr(Emax) - sqr(2.645));
  const UnstableParticles& ufs = apply<UnstableParticles>(event, "UFS");
  for (const Particle& p : ufs.particles(Cuts::abspid == idXi)) {
    double xp = p.momentum().p3().mod() / Pmax;
    _h_x->fill(xp);
    int sign = p.pid() / p.abspid();
    if (isDecay(p, {sign * 4232, -sign * 211})) {
      _r->fill("10.5"s);
    }
  }
  unsigned int nxi = ufs.particles(Cuts::abspid == 4232).size();
  _c_xi->fill(nxi);
}

/// Normalise histograms etc., after the run
void finalize() {
  normalize(_h_x);
  scale(_r, 1. / *_c_xi);
}
/// @}


/// @name Histograms
/// @{
Histo1DPtr _h_x;
BinnedHistoPtr<string> _r;
CounterPtr _c_xi;
/// @}

};

RIVET_DECLARE_PLUGIN(CLEOII_1995_I397770);

} ```