float WjetPolarizationAngle(LorentzVector p4w, LorentzVector p4lepton){
LorentzVector genp4_Wplus_;
LorentzVector genp4_lplus_;
LorentzVector genp4_Wplus_WCM_;
LorentzVector genp4_lplus_WCM_;
genp4_Wplus_=p4w;
genp4_lplus_=p4lepton;
ROOT::Math::Boost boost_Wplus_CM( genp4_Wplus_.BoostToCM().x(), genp4_Wplus_.BoostToCM().y(), genp4_Wplus_.BoostToCM().z() );
// cout<<" boost_Wplus_CM "<<boost_Wplus_CM<<endl;
// Get the W, lepton, and neutrino 4-vectors in the top rest frame
genp4_Wplus_WCM_ = boost_Wplus_CM * genp4_Wplus_;
genp4_lplus_WCM_ = boost_Wplus_CM * genp4_lplus_;
float theta_lplus_nu_WCM_ = -999.;
// cos(theta) - should rename variables
// theta is the angle between the lepton in the W rest frame and the W in the lab frame
theta_lplus_nu_WCM_ = genp4_lplus_WCM_.Px()*genp4_Wplus_.Px() +
genp4_lplus_WCM_.Py()*genp4_Wplus_.Py() +
genp4_lplus_WCM_.Pz()*genp4_Wplus_.Pz();
theta_lplus_nu_WCM_ /= genp4_lplus_WCM_.P()*genp4_Wplus_.P();
// cout<<"theta_lplus_nu_WCM_: "<<theta_lplus_nu_WCM_<<endl;
return theta_lplus_nu_WCM_;
}
float ttbarPolarizationAngle(LorentzVector p4top,LorentzVector p4w, LorentzVector p4lepton){
LorentzVector genp4_tplus_;
LorentzVector genp4_Wplus_;
LorentzVector genp4_lplus_;
LorentzVector genp4_Wplus_tCM_;
LorentzVector genp4_lplus_WCM_;
LorentzVector genp4_lplus_tCM_;
genp4_tplus_=p4top;
genp4_Wplus_=p4w;
genp4_lplus_=p4lepton;
// Boost from the LAB to the top CM
ROOT::Math::Boost boost_tplus_CM( genp4_tplus_.BoostToCM().x(), genp4_tplus_.BoostToCM().y(), genp4_tplus_.BoostToCM().z() );
// Boost from the LAB to the W CM
ROOT::Math::Boost boost_Wplus_CM( genp4_Wplus_.BoostToCM().x(), genp4_Wplus_.BoostToCM().y(), genp4_Wplus_.BoostToCM().z() );
// Get the W, lepton, and neutrino 4-vectors in the top rest frame
genp4_Wplus_tCM_ = boost_tplus_CM * genp4_Wplus_;
genp4_lplus_tCM_ = boost_tplus_CM * genp4_lplus_;
// Boost from the top CM to the W CM ( tW notation )
ROOT::Math::Boost boost_Wplus_tWCM( genp4_Wplus_tCM_.BoostToCM().x(), genp4_Wplus_tCM_.BoostToCM().y(), genp4_Wplus_tCM_.BoostToCM().z() );
// Boost from the W CM to the top CM ( Wt notation )
ROOT::Math::Boost boost_Wplus_WtCM = boost_Wplus_tWCM.Inverse();
// Get the lepton and neutrino 4-vectors in the W rest frame
//--- LAB -> top CM -> W CM ---//
genp4_lplus_WCM_ = boost_Wplus_tWCM * genp4_lplus_tCM_;
float theta_lplus_nu_WCM_ = -999.;
// cos(theta) - should rename variables
// theta is the angle between the lepton in the W rest frame and the W in the top rest frame
theta_lplus_nu_WCM_ = genp4_lplus_WCM_.Px()*genp4_Wplus_tCM_.Px() +
genp4_lplus_WCM_.Py()*genp4_Wplus_tCM_.Py() +
genp4_lplus_WCM_.Pz()*genp4_Wplus_tCM_.Pz();
theta_lplus_nu_WCM_ /= genp4_lplus_WCM_.P()*genp4_Wplus_tCM_.P();
return theta_lplus_nu_WCM_;
}
