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| // -*- C++ -*-
#include "Rivet/Analysis.hh"
#include "Rivet/Projections/Thrust.hh"
#include "Rivet/Projections/FinalState.hh"
#include "Rivet/Projections/Beam.hh"
namespace Rivet {
/// @brief azimuthal asymmetries in pipi Kpi and KK
class BABAR_2015_I1377201 : public Analysis {
public:
/// Constructor
RIVET_DEFAULT_ANALYSIS_CTOR(BABAR_2015_I1377201);
/// @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");
// declare the histos for the distributions
string type [3] = {"KK","Kpi","pipi"};
string charge[3] = {"Like","Opposite","All"};
unsigned int nbin=20;
for(unsigned int itype=0;itype<3;++itype) {
for(unsigned int icharge=0;icharge<3;++icharge) {
for(unsigned int ibin=0;ibin<16;++ibin) {
std::ostringstream title1;
title1 << "/TMP/h_thrust" << type[itype] << "_" << charge[icharge] << "_" << ibin+1;
book(_h_thrust[itype][icharge][ibin],title1.str(),nbin,0.,M_PI);
std::ostringstream title2;
title2 << "/TMP/h_hadron" << type[itype] << "_" << charge[icharge] << "_" << ibin+1;
book(_h_hadron[itype][icharge][ibin],title2.str(),nbin,0.,M_PI);
}
}
}
}
unsigned int iBin(double z) {
if (z<.2) return 0;
else if(z<.3) return 1;
else if(z<.5) return 2;
else return 3;
}
/// Perform the per-event analysis
void analyze(const Event& event) {
// get the axis, direction of incoming electron
const ParticlePair& beams = apply<Beam>(event, "Beams").beams();
Vector3 axis1;
if(beams.first.pid()>0)
axis1 = beams.first .momentum().p3().unit();
else
axis1 = beams.second.momentum().p3().unit();
// apply thrust cuts T > 0.8 and | cos θ th | < 0.6
Thrust thrust = apply<Thrust>(event,"Thrust");
if(thrust.thrust()<=0.8) vetoEvent;
if(cos(thrust.thrustAxis().polarAngle())>=0.6) vetoEvent;
// construct x,y,z axes for thrust defn
ThreeVector t_z = thrust.thrustAxis();
ThreeVector t_x = (axis1-t_z.dot(axis1)*t_z).unit();
ThreeVector t_y = t_z.cross(t_x);
// loop over the particles
Particles charged = apply<FinalState>(event,"FS").particles(Cuts::abspid==PID::PIPLUS || Cuts::abspid==PID::KPLUS);
for(unsigned int ix=0;ix<charged.size();++ix) {
// z and angle cut
const double x1=2.*charged[ix].momentum().t()/sqrtS();
if(x1<0.16||x1>.9) continue;
if(abs(t_z.angle(charged[ix].momentum().p3()))>0.25*M_PI) continue;
double dot1 = t_z.dot(charged[ix].p3());
for(unsigned int iy=ix+1;iy<charged.size();++iy) {
const double x2=2.*charged[iy].momentum().t()/sqrtS();
// z and angle cut
if(x2<0.16||x2>.9) continue;
if(abs(t_z.angle(charged[ix].momentum().p3()))>0.25*M_PI) continue;
// different hemi
double dot2 = t_z.dot(charged[iy].p3());
if(dot1*dot2>0.) continue;
Particle p1=charged[ix], p2=charged[iy];
double z1(x1),z2(x2);
// randomly order the particles
if(rand()/static_cast<double>(RAND_MAX) < 0.5 ) {
swap(p1,p2);
swap(z1,z2);
}
// thrust def
double phi12 = atan2(p1.p3().dot(t_y),p1.p3().dot(t_x))+atan2(p2.p3().dot(t_y),p2.p3().dot(t_x));
if(phi12>M_PI) phi12 -= 2*M_PI;
if(phi12<-M_PI) phi12 += 2*M_PI;
if(phi12<0.) phi12 = -phi12;
// hadron defn
ThreeVector h_z = p2.p3().unit();
ThreeVector h_x = (axis1-h_z.dot(axis1)*h_z).unit();
ThreeVector pt1 = p1.p3()-h_z.dot(p1.p3())*h_z;
double phi0 = pt1.angle(h_x);
if(phi0>M_PI) phi0 -= 2*M_PI;
if(phi0<-M_PI) phi0 += 2*M_PI;
int ibin = 4*iBin(z1)+iBin(z2);
// pi pi
if(p1.abspid()==PID::PIPLUS && p2.abspid()==PID::PIPLUS) {
if(p1.pid()==p2.pid()) {
_h_thrust[2][0][ibin]->fill(phi12);
_h_hadron[2][0][ibin]->fill(phi0);
}
else {
_h_thrust[2][1][ibin]->fill(phi12);
_h_hadron[2][1][ibin]->fill(phi0);
}
_h_thrust[2][2][ibin]->fill(phi12);
_h_hadron[2][2][ibin]->fill(phi0);
}
// K K
else if(p1.abspid()==PID::KPLUS && p2.abspid()==PID::KPLUS) {
if(p1.pid()==p2.pid()) {
_h_thrust[0][0][ibin]->fill(phi12);
_h_hadron[0][0][ibin]->fill(phi0);
}
else {
_h_thrust[0][1][ibin]->fill(phi12);
_h_hadron[0][1][ibin]->fill(phi0);
}
_h_thrust[0][2][ibin]->fill(phi12);
_h_hadron[0][2][ibin]->fill(phi0);
}
// K pi
else {
if(p1.pid()*p2.pid()>0) {
_h_thrust[1][0][ibin]->fill(phi12);
_h_hadron[1][0][ibin]->fill(phi0);
}
else {
_h_thrust[1][1][ibin]->fill(phi12);
_h_hadron[1][1][ibin]->fill(phi0);
}
_h_thrust[1][2][ibin]->fill(phi12);
_h_hadron[1][2][ibin]->fill(phi0);
}
}
}
}
pair<double,double> calcAsymmetry(Scatter2DPtr hist,double fact=1.) {
double sum1(0.),sum2(0.);
for (auto point : hist->points() ) {
double Oi = point.y();
if(Oi==0. || std::isnan(Oi) ) continue;
double ai = 1.;
double bi = (sin(fact*point.xMax())-sin(fact*point.xMin()))/(point.xMax()-point.xMin())/fact;
double Ei = point.yErrAvg();
sum1 += sqr(bi/Ei);
sum2 += bi/sqr(Ei)*(Oi-ai);
}
if(sum1==0.) return make_pair(0.,0.);
return make_pair(sum2/sum1*1e4,sqrt(1./sum1)*1e4);
}
/// Normalise histograms etc., after the run
void finalize() {
for(unsigned int itype=0;itype<3;++itype) {
for(unsigned int icharge=0;icharge<3;++icharge) {
for(unsigned int ibin=0;ibin<16;++ibin) {
normalize(_h_thrust[itype][icharge][ibin]);
normalize(_h_hadron[itype][icharge][ibin]);
}
}
}
// construct ther ratios
// declare the histos for the distributions
string type [3] = {"pipi","Kpi","KK"};
string charge[3] = {"Like","Opposite","All"};
for(unsigned int itype=0;itype<3;++itype) {
Scatter3DPtr h3_thrust_UL;
book(h3_thrust_UL,2*itype+1,1,2,0);
Scatter3DPtr h3_thrust_UC;
book(h3_thrust_UC,2*itype+1,1,3,0);
Scatter3DPtr h3_hadron_UL;
book(h3_hadron_UL,2*itype+2,1,2,0);
Scatter3DPtr h3_hadron_UC;
book(h3_hadron_UC,2*itype+2,1,3,0);
unsigned int ihist=1;
Scatter2DPtr h2_thrust_UL;
book(h2_thrust_UL,7+2*itype,ihist,2);
Scatter2DPtr h2_thrust_UC;
book(h2_thrust_UC,7+2*itype,ihist,3);
Scatter2DPtr h2_hadron_UL;
book(h2_hadron_UL,8+2*itype,ihist,2);
Scatter2DPtr h2_hadron_UC;
book(h2_hadron_UC,8+2*itype,ihist,3);
Scatter3D temphisto1(refData<Scatter3D>(2*itype+1, 1, 2));
Scatter3D temphisto2(refData<Scatter3D>(2*itype+2, 1, 2));
for(unsigned int ibin=0;ibin<16;++ibin) {
const Point3D & p1 = temphisto1.points()[ibin];
const Point3D & p2 = temphisto2.points()[ibin];
if(ibin>0 && ibin%4==0) {
++ihist;
book(h2_thrust_UL,7+2*itype,ihist,2);
book(h2_thrust_UC,7+2*itype,ihist,3);
book(h2_hadron_UL,8+2*itype,ihist,2);
book(h2_hadron_UC,8+2*itype,ihist,3);
}
// thrust direction
// opposite/like sign
std::ostringstream title1;
title1 << "/TMP/R_thrust_" << type[itype] << "_UL_" << ibin+1;
Scatter2DPtr htemp;
book(htemp,title1.str());
divide(_h_thrust[itype][1][ibin],
_h_thrust[itype][0][ibin],htemp);
pair<double,double> asym = calcAsymmetry(htemp);
h3_thrust_UL->addPoint(p1.x() ,p1.y() ,asym.first,
p1.xErrs(),p1.yErrs(),make_pair(asym.second,asym.second) );
h2_thrust_UL->addPoint(p1.y() ,asym.first,p1.yErrs(),make_pair(asym.second,asym.second) );
// opposite/all sign
std::ostringstream title2;
title2 << "/TMP/R_thrust_" << type[itype] << "_UC_" << ibin+1;
book(htemp,title2.str());
divide(_h_thrust[itype][1][ibin],
_h_thrust[itype][2][ibin],htemp);
asym = calcAsymmetry(htemp);
h3_thrust_UC->addPoint(p1.x() ,p1.y() ,asym.first,
p1.xErrs(),p1.yErrs(),make_pair(asym.second,asym.second) );
h2_thrust_UC->addPoint(p1.y() ,asym.first,p1.yErrs(),make_pair(asym.second,asym.second) );
// hadron dirn
// opposite/like sign
std::ostringstream title3;
title3 << "/TMP/R_hadron_" << type[itype] << "_UL_" << ibin+1;
book(htemp,title3.str());
divide(_h_hadron[itype][1][ibin],
_h_hadron[itype][0][ibin],htemp);
asym = calcAsymmetry(htemp,2.);
h3_hadron_UL->addPoint(p2.x() ,p2.y() ,asym.first,
p2.xErrs(),p2.yErrs(),make_pair(asym.second,asym.second) );
h2_hadron_UL->addPoint(p2.y() ,asym.first,p2.yErrs(),make_pair(asym.second,asym.second) );
// opposite/all sign
std::ostringstream title4;
title4 << "/TMP/R_hadron_" << type[itype] << "_UC_" << ibin+1;
book(htemp,title4.str());
divide(_h_hadron[itype][1][ibin],
_h_hadron[itype][2][ibin],htemp);
asym = calcAsymmetry(htemp,2.);
h3_hadron_UC->addPoint(p2.x() ,p2.y() ,asym.first,
p2.xErrs(),p2.yErrs(),make_pair(asym.second,asym.second) );
h2_hadron_UC->addPoint(p2.y() ,asym.first,p2.yErrs(),make_pair(asym.second,asym.second) );
}
}
}
//@}
/// @name Histograms
//@{
Histo1DPtr _h_thrust[3][3][16],_h_hadron[3][3][16];
//@}
};
RIVET_DECLARE_PLUGIN(BABAR_2015_I1377201);
}
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