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| // -*- C++ -*-
#include "Rivet/Analysis.hh"
#include "Rivet/Projections/Beam.hh"
#include "Rivet/Projections/FinalState.hh"
#include "Rivet/Projections/ChargedFinalState.hh"
#include "Rivet/Projections/UnstableParticles.hh"
namespace Rivet {
class DELPHI_2011_I890503 : public Analysis {
public:
/// Constructor
DELPHI_2011_I890503()
: Analysis("DELPHI_2011_I890503")
{
}
/// Book projections and histograms
void init() {
declare(Beam(), "Beams");
declare(ChargedFinalState(), "FS");
declare(UnstableParticles(), "UFS");
book(_histXbweak ,1, 1, 1);
book(_histMeanXbweak ,2, 1, 1);
}
void analyze(const Event& e) {
// Even if we only generate hadronic events, we still need a cut on numCharged >= 2.
if (apply<FinalState>(e, "FS").particles().size() < 2) {
MSG_DEBUG("Failed ncharged cut");
vetoEvent;
}
MSG_DEBUG("Passed ncharged cut");
// Get beams and average beam momentum
const ParticlePair& beams = apply<Beam>(e, "Beams").beams();
const double meanBeamMom = ( beams.first.p3().mod() +
beams.second.p3().mod() ) / 2.0;
MSG_DEBUG("Avg beam momentum = " << meanBeamMom);
const UnstableParticles& ufs = apply<UnstableParticles>(e, "UFS");
// Get Bottom hadrons
const Particles bhads = filter_select(ufs.particles(), isBottomHadron);
for (const Particle& bhad : bhads) {
// Check for weak decay, i.e. no more bottom present in children
if (bhad.children(lastParticleWith(hasBottom)).empty()) {
const double xp = bhad.E()/meanBeamMom;
_histXbweak->fill(xp);
_histMeanXbweak->fill(_histMeanXbweak->bin(0).xMid(), xp);
}
}
}
// Finalize
void finalize() {
normalize(_histXbweak);
}
private:
Histo1DPtr _histXbweak;
Profile1DPtr _histMeanXbweak;
};
// The hook for the plugin system
RIVET_DECLARE_PLUGIN(DELPHI_2011_I890503);
}
|