// -*- C++ -*-
#include "Rivet/Analysis.hh"
#include "Rivet/Projections/UnstableParticles.hh"
namespace Rivet {
/// @brief D -> pi,K semi-leptonic q^2
class CLEO_2004_I654843 : public Analysis {
public:
/// Constructor
RIVET_DEFAULT_ANALYSIS_CTOR(CLEO_2004_I654843);
/// @name Analysis methods
/// @{
/// Book histograms and initialise projections before the run
void init() {
// Initialise and register projections
declare(UnstableParticles(Cuts::abspid==PID::D0), "UFS");
// histograms
book(_h_q2_D0_K ,1,1,1);
book(_h_q2_D0_pi,1,1,2);
}
// Calculate the Q2 using mother and daugher meson
double q2(const Particle& B, int mesonID) {
FourMomentum q = B.mom() - filter_select(B.children(), Cuts::abspid==abs(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()) {
if(isSemileptonicDecay(p, {PID::PIMINUS, PID::POSITRON, PID::NU_E}) ||
isSemileptonicDecay(p, {PID::PIPLUS , PID::ELECTRON, PID::NU_EBAR}) )
_h_q2_D0_pi->fill(q2(p, PID::PIMINUS));
else if(isSemileptonicDecay(p, {PID::KMINUS, PID::POSITRON, PID::NU_E}) ||
isSemileptonicDecay(p, {PID::KPLUS , PID::ELECTRON, PID::NU_EBAR}))
_h_q2_D0_K ->fill(q2(p, PID::KMINUS));
}
}
/// Normalise histograms etc., after the run
void finalize() {
normalize(_h_q2_D0_K );
normalize(_h_q2_D0_pi);
}
/// @}
/// @name Histograms
/// @{
Histo1DPtr _h_q2_D0_K, _h_q2_D0_pi;
CounterPtr _nD0,_nDp;
/// @}
};
RIVET_DECLARE_PLUGIN(CLEO_2004_I654843);
}