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| // -*- C++ -*-
#include "Rivet/Analysis.hh"
#include "Rivet/Projections/UnstableParticles.hh"
namespace Rivet {
/// @brief D -> eta semi-leptonic q^2
class CLEOC_2011_I875526 : public Analysis {
public:
/// Constructor
RIVET_DEFAULT_ANALYSIS_CTOR(CLEOC_2011_I875526);
/// @name Analysis methods
///@{
/// Book histograms and initialise projections before the run
void init() {
// Initialise and register projections
declare(UnstableParticles(), "UFS");
// histograms
book(_h_q2_Dp_eta_A,1,1,1);
book(_h_q2_Dp_eta_B,1,1,2);
book(_nDp,"TMP/nDp");
}
// Calculate the Q2 using mother and daugher meson
double q2(const Particle& B, int mesonID) {
FourMomentum q = B.mom() - filter_select(B.children(), Cuts::pid==mesonID)[0];
return q*q;
}
// Check for explicit decay into pdgids
bool isSemileptonicDecay(const Particle& mother, vector<int> ids) {
// 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) {
// Loop over D mesons
for(const Particle& p : apply<UnstableParticles>(event, "UFS").particles(Cuts::abspid==PID::DPLUS )) {
_nDp->fill();
if(isSemileptonicDecay(p, {PID::ETA, PID::POSITRON, PID::NU_E}) ||
isSemileptonicDecay(p, {PID::ETA, PID::ELECTRON, PID::NU_EBAR})) {
double q = q2(p, PID::ETA);
_h_q2_Dp_eta_A->fill(q);
_h_q2_Dp_eta_B->fill(q);
}
}
}
/// Normalise histograms etc., after the run
void finalize() {
scale(_h_q2_Dp_eta_A, 1./ *_nDp);
scale(_h_q2_Dp_eta_B, 1./ *_nDp);
}
///@}
/// @name Histograms
///@{
Histo1DPtr _h_q2_Dp_eta_A,_h_q2_Dp_eta_B;
CounterPtr _nD0,_nDp;
///@}
};
RIVET_DECLARE_PLUGIN(CLEOC_2011_I875526);
}
|