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| // -*- C++ -*-
#include "Rivet/Analysis.hh"
#include "Rivet/Projections/FinalState.hh"
#include "Rivet/Projections/Thrust.hh"
#include "Rivet/Projections/Beam.hh"
namespace Rivet {
/// @brief pi, kaon and proton spectra at 10.58 GeV
class BELLE_2019_I1718551 : public Analysis {
public:
/// Constructor
RIVET_DEFAULT_ANALYSIS_CTOR(BELLE_2019_I1718551);
/// @name Analysis methods
//@{
/// Book histograms and initialise projections before the run
void init() {
// projections
const FinalState fs;
declare(fs, "FS");
declare(Thrust(fs),"Thrust");
declare(Beam(), "Beams");
for(unsigned int ix=0;ix<6;++ix) {
double xmin=0.05;
for(unsigned int iy=0;iy<18;++iy) {
xmin+=0.05;
// pions
if(ix==0&&iy>15) continue;
Histo1DPtr temp1;
book(temp1,1,ix+1,iy+1);
_pion[ix].add(xmin,xmin+0.05,temp1);
// kaons
Histo1DPtr temp2;
book(temp2,2,ix+1,iy+1);
_kaon[ix].add(xmin,xmin+0.05,temp2);
if(iy>15 || (iy>14&&ix<3) || (iy>11&&ix==0)) continue;
// protons
Histo1DPtr temp3;
book(temp3,3,ix+1,iy+1);
_proton[ix].add(xmin,xmin+0.05,temp3);
}
}
}
/// Perform the per-event analysis
void analyze(const Event& event) {
// Get beams and average beam momentum
const ParticlePair& beams = apply<Beam>(event, "Beams").beams();
const double meanBeamMom = ( beams.first.p3().mod() +
beams.second.p3().mod() ) / 2.0;
// get the thrust
const double tbins[6]={0.7,0.8,0.85,0.9,0.95,1.0};
const Thrust& thrust = apply<Thrust>(event, "Thrust");
// find the thrust bin
unsigned int ithrust=0;
for(;ithrust<6;++ithrust)
if(thrust.thrust()<=tbins[ithrust]) break;
Vector3 a1 = thrust.thrustMajorAxis();
Vector3 a2 = thrust.thrustMinorAxis();
// loop over the charged hadrons
const FinalState & fs = apply<FinalState>(event, "FS");
for(const Particle & charged : fs.particles(Cuts::abspid==211 or
Cuts::abspid==321 or
Cuts::abspid==2212)) {
double xE = charged.momentum().t()/meanBeamMom;
double pT = sqrt(sqr(a1.dot(charged.momentum().p3()))+
sqr(a2.dot(charged.momentum().p3())));
if(charged.abspid()==211)
_pion [ithrust].fill(xE,pT);
else if(charged.abspid()==321)
_kaon [ithrust].fill(xE,pT);
else if(charged.abspid()==2212)
_proton[ithrust].fill(xE,pT);
}
}
/// Normalise histograms etc., after the run
void finalize() {
// scale factor including bin width in x_E
double fact = crossSection()/femtobarn/sumOfWeights()/0.05;
for(unsigned int ix=0;ix<6;++ix) {
for(Histo1DPtr histo : _pion [ix].histos()) scale(histo,fact);
for(Histo1DPtr histo : _kaon [ix].histos()) scale(histo,fact);
for(Histo1DPtr histo : _proton[ix].histos()) scale(histo,fact);
}
}
//@}
/// @name Histograms
//@{
BinnedHistogram _pion[6],_kaon[6],_proton[6];
//@}
};
RIVET_DECLARE_PLUGIN(BELLE_2019_I1718551);
}
|