// -*- C++ -*-
#include "Rivet/Analysis.hh"
#include "Rivet/Projections/UnstableParticles.hh"
#include "Rivet/Projections/DecayedParticles.hh"
namespace Rivet {
/// @brief Bbar0 -> Lambda_c+ Lambdabar_c- Kbar0
class BELLE_2018_I1679584 : public Analysis {
public:
/// Constructor
RIVET_DEFAULT_ANALYSIS_CTOR(BELLE_2018_I1679584);
/// @name Analysis methods
/// @{
/// Book histograms and initialise projections before the run
void init() {
UnstableParticles ufs = UnstableParticles(Cuts::abspid==511);
declare(ufs, "UFS");
DecayedParticles B0(ufs);
B0.addStable( 4122);
B0.addStable(-4122);
B0.addStable( 310);
declare(B0, "B0");
// histos
for(unsigned int ix=0;ix<2;++ix)
book(_h[ix],1+ix,1,1);
}
/// Perform the per-event analysis
void analyze(const Event& event) {
static const map<PdgId,unsigned int> & mode = { { 4122,1},{-4122,1}, { 310,1}};
DecayedParticles B0 = apply<DecayedParticles>(event, "B0");
// loop over particles
for(unsigned int ix=0;ix<B0.decaying().size();++ix) {
if(!B0.modeMatches(ix,3,mode))
continue;
const Particle & LamC = B0.decayProducts()[ix].at( 4122)[0];
const Particle & LamCBar = B0.decayProducts()[ix].at(-4122)[0];
const Particle & K0 = B0.decayProducts()[ix].at( 310)[0];
if(B0.decaying()[ix].pid()<0)
_h[0]->fill((LamC .momentum()+K0.momentum()).mass());
else
_h[0]->fill((LamCBar.momentum()+K0.momentum()).mass());
_h[1]->fill((LamC.momentum()+LamCBar.momentum()).mass());
}
}
/// Normalise histograms etc., after the run
void finalize() {
for(unsigned int ix=0;ix<2;++ix)
normalize(_h[ix],1.,false);
}
/// @}
/// @name Histograms
/// @{
Histo1DPtr _h[2];
/// @}
};
RIVET_DECLARE_PLUGIN(BELLE_2018_I1679584);
}