// -*- C++ -*-
#include "Rivet/Analysis.hh"
#include "Rivet/Projections/UnstableParticles.hh"
#include "Rivet/Projections/DecayedParticles.hh"
namespace Rivet {
/// @brief psi(2S) -> J/Psi pi pi
class CLEOC_2008_I784516 : public Analysis {
public:
/// Constructor
RIVET_DEFAULT_ANALYSIS_CTOR(CLEOC_2008_I784516);
/// @name Analysis methods
/// @{
/// Book histograms and initialise projections before the run
void init() {
// Initialise and register projections
UnstableParticles ufs = UnstableParticles(Cuts::pid==100443);
declare(ufs, "UFS");
DecayedParticles psi(ufs);
psi.addStable(PID::PI0);
psi.addStable(PID::JPSI);
declare(psi, "psi");
for(unsigned int ix=0;ix<2;++ix)
book(_h[ix],1,1,1+ix);
}
/// Perform the per-event analysis
void analyze(const Event& event) {
static const map<PdgId,unsigned int> & mode1 = { { 211,1}, {-211,1}, { 443,1} };
static const map<PdgId,unsigned int> & mode2 = { { 111,2} , { 443,1} };
DecayedParticles psi = apply<DecayedParticles>(event, "psi");
// loop over particles
for(unsigned int ix=0;ix<psi.decaying().size();++ix) {
if(psi.modeMatches(ix,3,mode1)) {
const Particle & pip = psi.decayProducts()[ix].at( 211)[0];
const Particle & pim = psi.decayProducts()[ix].at(-211)[0];
_h[0]->fill((pip.momentum()+pim.momentum()).mass());
}
else if(psi.modeMatches(ix,3,mode2)) {
const Particles & pi0 = psi.decayProducts()[ix].at( 111);
_h[1]->fill((pi0[0].momentum()+pi0[1].momentum()).mass());
}
}
}
/// Normalise histograms etc., after the run
void finalize() {
for(unsigned int ix=0;ix<2;++ix) normalize(_h[ix]);
}
/// @}
/// @name Histograms
/// @{
Histo1DPtr _h[2];
/// @}
};
RIVET_DECLARE_PLUGIN(CLEOC_2008_I784516);
}