Rivet analyses

title: BABAR_2007_I746745

Spectrum for $\Omega_c^0$ production at the $\Upsilon(4S)$

Experiment: BABAR (PEP-II)

Inspire ID: 746745

Status: VALIDATED

Authors: - Peter Richardson

References: - Phys.Rev.Lett. 99 (2007) 062001

Beams: e+ e-

Beam energies: (5.3, 5.3)GeV

Run details: - e+e- > hadrons at Upsilon(4S) including both resonant and non-resonance

Spectrum for $\Omega_c^0$ production at the $\Upsilon(4S)$ measured by BaBar. The spectrum includes a contribution from both the $\Upsilon(4S)$ and continuum $c\bar{c}$ events.

Source code:BABAR_2007_I746745.cc

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

include "Rivet/Analysis.hh"

include "Rivet/Projections/UnstableParticles.hh"

namespace Rivet {

/// @brief Spectrum for Omega_c class BABAR_2007_I746745 : public Analysis { public:

/// Constructor
RIVET_DEFAULT_ANALYSIS_CTOR(BABAR_2007_I746745);


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

/// Book histograms and initialise projections before the run
void init() {
  declare(UnstableParticles(), "UFS");
  book(_h_p, 1, 1, 1);
  book(_b, 2, 1, 1);
  book(_r, 3, 1, 1);
  book(_ups, "/TMP/ups");
}


/// Perform the per-event analysis
void analyze(const Event& event) {
  static const int idOmega = 4332;
  const UnstableParticles& ufs = apply<UnstableParticles>(event, "UFS");
  bool ups = !ufs.particles(Cuts::pid == 300553).empty();
  if (ups) _ups->fill();
  for (const Particle& p : ufs.particles(Cuts::abspid == idOmega)) {
    _h_p->fill(p.momentum().p3().mod());
    if (p.children().size() == 2) {
      int sign = p.pid() / p.abspid();
      if ((p.children()[0].pid() == sign * 3334 && p.children()[1].pid() == sign * 211)
          || (p.children()[1].pid() == sign * 3334 && p.children()[0].pid() == sign * 211)) {
        if (ups)
          _b->fill();
        else
          _r->fill("10.58"s);
      }
    }
  }
}


/// Normalise histograms etc., after the run
void finalize() {
  normalize(_h_p);
  if (_ups->effNumEntries() != 0) {
    scale(_b, 0.5 / *_ups);
  }
  scale(_r, crossSection() / sumOfWeights() / femtobarn);
}
/// @}


/// @name Histograms
/// @{
Histo1DPtr _h_p;
BinnedHistoPtr<string> _r;
CounterPtr _b, _ups;
/// @}

};

RIVET_DECLARE_PLUGIN(BABAR_2007_I746745);

} ```