// -*- C++ -*-
#include "Rivet/Analysis.hh"
#include "Rivet/Projections/UnstableParticles.hh"
#include "Rivet/Projections/DecayedParticles.hh"
namespace Rivet {
/// @brief tau -> pi- KS0 KS0 nu
class BABAR_2012_I1125567 : public Analysis {
public:
/// Constructor
RIVET_DEFAULT_ANALYSIS_CTOR(BABAR_2012_I1125567);
/// @name Analysis methods
/// @{
/// Book histograms and initialise projections before the run
void init() {
// Initialise and register projections
UnstableParticles ufs = UnstableParticles(Cuts::abspid==15);
declare(ufs, "UFS");
DecayedParticles TAU(ufs);
TAU.addStable(310);
TAU.addStable(111);
declare(TAU, "TAU");
// histograms
for(unsigned int ix=0;ix<3;++ix) {
book(_h[ix],1,1,1+ix);
}
}
/// Perform the per-event analysis
void analyze(const Event& event) {
static const map<PdgId,unsigned int> & mode = { { 310,2}, {-211,1},{ 16,1}};
static const map<PdgId,unsigned int> & modeCC = { { 310,2}, { 211,1},{-16,1}};
DecayedParticles TAU = apply<DecayedParticles>(event, "TAU");
// loop over particles
for(unsigned int ix=0;ix<TAU.decaying().size();++ix) {
int sign = 1;
if(TAU.decaying()[ix].pid()>0 &&
TAU.modeMatches(ix,4,mode)) sign=1;
else if (TAU.decaying()[ix].pid()<0 &&
TAU.modeMatches(ix,4,modeCC)) sign=-1;
else
continue;
const Particle & pim = TAU.decayProducts()[ix].at(-211*sign)[0];
const Particles & K0 = TAU.decayProducts()[ix].at( 310);
_h[0]->fill((pim.momentum()+K0[0].momentum()+K0[1].momentum()).mass());
_h[2]->fill((K0[0].momentum()+K0[1].momentum()).mass());
for(unsigned int ix=0;ix<2;++ix) {
_h[1]->fill((pim.momentum()+K0[ix].momentum()).mass());
}
}
}
/// Normalise histograms etc., after the run
void finalize() {
for(unsigned int ix=0;ix<3;++ix) {
normalize(_h[ix],1.,false);
}
}
/// @}
/// @name Histograms
/// @{
Histo1DPtr _h[3];
/// @}
};
RIVET_DECLARE_PLUGIN(BABAR_2012_I1125567);
}