// -*- C++ -*-
#include "Rivet/Analysis.hh"
#include "Rivet/Projections/UnstableParticles.hh"
namespace Rivet {
/// @brief Semileptonic Lambda_c+
class BESIII_2022_I2611489 : public Analysis {
public:
/// Constructor
RIVET_DEFAULT_ANALYSIS_CTOR(BESIII_2022_I2611489);
/// @name Analysis methods
/// @{
/// Book histograms and initialise projections before the run
void init() {
// projections
declare(UnstableParticles(Cuts::abspid==4122),"UFS");
// histos
book(_h,1,1,1);
}
void findDecayProducts(Particle parent, Particles & em, Particles & ep,
Particles & nue, Particles & nueBar) {
for(const Particle & p : parent.children()) {
if(p.pid() == PID::EMINUS) {
em.push_back(p);
}
else if(p.pid() == PID::EPLUS) {
ep.push_back(p);
}
else if(p.pid() == PID::NU_E) {
nue.push_back(p);
}
else if(p.pid() == PID::NU_EBAR) {
nueBar.push_back(p);
}
else if(!PID::isHadron(p.pid())) {
findDecayProducts(p,em,ep,nue,nueBar);
}
}
}
/// Perform the per-event analysis
void analyze(const Event& event) {
for(const Particle & p : apply<UnstableParticles>(event, "UFS").particles()) {
Particles em,ep,nue,nueBar;
findDecayProducts(p,em,ep,nue,nueBar);
if(em.size()==1 && nueBar.size()==1) {
double pmod = em[0].momentum().p3().mod();
_h->fill(pmod);
}
else if(ep.size()==1 && nue.size()==1) {
double pmod = ep[0].momentum().p3().mod();
_h->fill(pmod);
}
}
}
/// Normalise histograms etc., after the run
void finalize() {
normalize(_h,1.,false);
}
/// @}
/// @name Histograms
/// @{
Histo1DPtr _h;
/// @}
};
RIVET_DECLARE_PLUGIN(BESIII_2022_I2611489);
}