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| // -*- C++ -*-
#include "Rivet/Analysis.hh"
#include "Rivet/Projections/Beam.hh"
#include "Rivet/Projections/Thrust.hh"
#include "Rivet/Projections/UnstableParticles.hh"
#include "Rivet/Projections/ChargedFinalState.hh"
namespace Rivet {
/// @brief Lambda production at 29 GeV
class HRS_1986_I17781 : public Analysis {
public:
/// Constructor
RIVET_DEFAULT_ANALYSIS_CTOR(HRS_1986_I17781);
/// @name Analysis methods
///@{
/// Book histograms and initialise projections before the run
void init() {
declare(UnstableParticles(), "UFS");
const ChargedFinalState cfs;
declare(cfs, "CFS");
declare(Thrust(cfs), "Thrust");
book(_h_spect,1,1,1);
book(_h_rap ,2,1,1);
book(_h_mult ,3,1,1);
}
/// Perform the per-event analysis
void analyze(const Event& event) {
const ChargedFinalState& cfs = apply<ChargedFinalState>(event, "CFS");
const size_t numParticles = cfs.particles().size();
// Even if we only generate hadronic events, we still need a cut on numCharged >= 2.
if (numParticles < 2) {
MSG_DEBUG("Failed leptonic event cut");
vetoEvent;
}
MSG_DEBUG("Passed leptonic event cut");
// Thrust
const Thrust& thrust = apply<Thrust>(event, "Thrust");
UnstableParticles ufs = apply<UnstableParticles>(event,"UFS");
for(const Particle & p : ufs.particles(Cuts::abspid==3122)) {
double xE = 2.*p.E()/sqrtS();
Vector3 mom3 = p.p3();
const double energy = p.E();
double modp = mom3.mod();
double beta = modp/energy;
const double momT = dot(thrust.thrustAxis(), mom3);
const double rapidityT = 0.5 * std::log((energy + momT) / (energy - momT));
_h_spect->fill(xE,1./beta);
_h_rap->fill(abs(rapidityT));
_h_mult->fill(sqrtS());
}
}
/// Normalise histograms etc., after the run
void finalize() {
scale( _h_spect, sqr(sqrtS())*crossSection()/nanobarn/sumOfWeights());
scale( _h_rap , 1./sumOfWeights());
scale( _h_mult , 1./sumOfWeights());
}
///@}
/// @name Histograms
///@{
Histo1DPtr _h_spect,_h_rap,_h_mult;
///@}
};
RIVET_DECLARE_PLUGIN(HRS_1986_I17781);
}
|