Pythia8::Sigma2qqbar2lStarlBar Class Reference

Inheritance diagram for Pythia8::Sigma2qqbar2lStarlBar:

Collaboration diagram for Pythia8::Sigma2qqbar2lStarlBar:

Public Member Functions
	Sigma2qqbar2lStarlBar (int idlIn)
void	initProc ()
virtual double	sigmaHat ()
void	sigmaKin ()
void	setIdColAcol ()
double	weightDecay (Event &process, int iResBeg, int iResEnd)
virtual std::string	name () const
virtual int	code () const
virtual std::string	inFlux () const
virtual int	id3Mass () const

Public Attributes
int	idl
int	idRes
int	codeSave
std::string	nameSave
double	Lambda
double	preFac
double	openFracPos
double	openFracNeg
double	sigma
double	m2ResTimes4

Detailed Description

Definition at line 40 of file Sigma2qqbar2lStarlBar.cxx.

Constructor & Destructor Documentation

Sigma2qqbar2lStarlBar()

Pythia8::Sigma2qqbar2lStarlBar::Sigma2qqbar2lStarlBar ( int  idlIn )

inline

Definition at line 44 of file Sigma2qqbar2lStarlBar.cxx.

                                     : idl(idlIn),
    idRes(0), codeSave(0),
    Lambda(0.), preFac(0.), openFracPos(0.), openFracNeg(0.), sigma(0.), m2ResTimes4(0.){};

Member Function Documentation

code()

virtual int Pythia8::Sigma2qqbar2lStarlBar::code ( ) const

inlinevirtual

Definition at line 148 of file Sigma2qqbar2lStarlBar.cxx.

{return codeSave;}

id3Mass()

virtual int Pythia8::Sigma2qqbar2lStarlBar::id3Mass ( ) const

inlinevirtual

Definition at line 150 of file Sigma2qqbar2lStarlBar.cxx.

{return std::abs(idRes);}

inFlux()

virtual std::string Pythia8::Sigma2qqbar2lStarlBar::inFlux ( ) const

inlinevirtual

Definition at line 149 of file Sigma2qqbar2lStarlBar.cxx.

{return "qqbarSame";}

initProc()

void Pythia8::Sigma2qqbar2lStarlBar::initProc ( )

inline

Definition at line 52 of file Sigma2qqbar2lStarlBar.cxx.

                    {
      
      // Set up process properties from the chosen lepton flavour.
      idRes         = 4000000 + idl;
      codeSave      = 4060 + idl;
      if      (idl == 11) nameSave = "q qbar -> e^*+- e^-+";
      else if (idl == 12) nameSave = "q qbar -> nu_e^* nu_ebar"; 
      else if (idl == 13) nameSave = "q qbar -> mu^*+- mu^-+"; 
      else if (idl == 14) nameSave = "q qbar -> nu_mu^* nu_mubar"; 
      else if (idl == 15) nameSave = "q qbar -> tau^*+- tau^-+"; 
      else                nameSave = "q qbar -> nu_tau^* nu_taubar";
      
      // Secondary open width fractions.
      openFracPos = particleDataPtr->resOpenFrac( idRes);
      openFracNeg = particleDataPtr->resOpenFrac(-idRes);
      
      // Locally stored properties and couplings.
      Lambda        = settingsPtr->parm("ExcitedFermion:Lambda");
      preFac        = (M_PI / pow4(Lambda)) * (openFracPos + openFracNeg) / 3.; // orig pythia
      //preFac        = (M_PI / pow4(Lambda)) * (openFracPos + openFracNeg) / 6.;
      
    } 

name()

virtual std::string Pythia8::Sigma2qqbar2lStarlBar::name ( ) const

inlinevirtual

Definition at line 147 of file Sigma2qqbar2lStarlBar.cxx.

{return nameSave;}

setIdColAcol()

void Pythia8::Sigma2qqbar2lStarlBar::setIdColAcol ( )

inline

Definition at line 95 of file Sigma2qqbar2lStarlBar.cxx.

                        {
      
      // Flavours: either lepton or antilepton may be excited.
      if (rndmPtr->flat() * (openFracPos + openFracNeg) < openFracPos) {
        setId( id1, id2, idRes, -idl);
        if (id1 < 0) swapTU = true; 
      } else {
        setId( id1, id2, -idRes, idl);
        if (id1 > 0) swapTU = true; 
      }  
      
      // Colour flow trivial.
      if (id1 > 0) setColAcol( 1, 0, 0, 1, 0, 0, 0, 0);
      else         setColAcol( 0, 1, 1, 0, 0, 0, 0, 0);
      
    }

sigmaHat()

virtual double Pythia8::Sigma2qqbar2lStarlBar::sigmaHat ( )

inlinevirtual

Definition at line 77 of file Sigma2qqbar2lStarlBar.cxx.

{return sigma;}

sigmaKin()

void Pythia8::Sigma2qqbar2lStarlBar::sigmaKin ( )

inline

Definition at line 82 of file Sigma2qqbar2lStarlBar.cxx.

                    {
      
      // later this gets multiplied further with sH*(1-s3/sH)
      
      sigma = preFac * (-uH) * (sH + tH) / sH2;  // orig pythia
      //sigma = preFac * (2. + s3/sH) *(1 - s3/sH) ;
      //Baur sigma = preFac * ( 1 + 1./3.*(sH - s3)/(sH+s3) ) * (1 - s3/sH) * (1 + s3/sH);
    }

weightDecay()

double Pythia8::Sigma2qqbar2lStarlBar::weightDecay ( Event &  process, int  iResBeg, int  iResEnd  )

inline

Definition at line 114 of file Sigma2qqbar2lStarlBar.cxx.

                                    {
      
      // l* should sit in entry 5. and 6 Sequential Z/W decay assumed isotropic.
      if (iResBeg != 5 && iResEnd != 5 && iResBeg != 6 && iResEnd != 6 ) return 1.; 
      
      // Phase space factors.
      double mr1    = pow2(process[7].m() / process[5].m());
      double mr2    = pow2(process[8].m() / process[5].m()); 
      
      // Reconstruct decay angle in l* CoM frame.
      int  idAbs3 = process[7].idAbs();
      Vec4 pLStarCom = (idAbs3 < 20) ? process[8].p() : process[7].p();
      //Vec4 pLStarCom = (idAbs3 < 20) ? process[7].p() : process[8].p(); // orig pythia
      pLStarCom.bstback(process[5].p());
      double cosThe = costheta(pLStarCom, process[5].p());
      double wt     = 1.; 
      
      // Decay, l* -> l + gamma/Z^0/W^+-).
      int idBoson   = (idAbs3 < 20) ? process[8].idAbs() : process[7].idAbs();
      if (idBoson == 22) {
        wt          = 0.5 * (1. + cosThe);
      } else if (idBoson == 23 || idBoson == 24) {
        double mrB  = (idAbs3 < 20) ? mr2 : mr1;
        double kTrm = 0.5 * (mrB * (1. - cosThe));
        wt          = (1. + cosThe + kTrm) / (2 + mrB);
      } 
      
      // Done.
      return wt;
    }

Member Data Documentation

codeSave

int Pythia8::Sigma2qqbar2lStarlBar::codeSave

Definition at line 156 of file Sigma2qqbar2lStarlBar.cxx.

idl

int Pythia8::Sigma2qqbar2lStarlBar::idl

Definition at line 156 of file Sigma2qqbar2lStarlBar.cxx.

idRes

int Pythia8::Sigma2qqbar2lStarlBar::idRes

Definition at line 156 of file Sigma2qqbar2lStarlBar.cxx.

Lambda

double Pythia8::Sigma2qqbar2lStarlBar::Lambda

Definition at line 158 of file Sigma2qqbar2lStarlBar.cxx.

m2ResTimes4

double Pythia8::Sigma2qqbar2lStarlBar::m2ResTimes4

Definition at line 159 of file Sigma2qqbar2lStarlBar.cxx.

nameSave

std::string Pythia8::Sigma2qqbar2lStarlBar::nameSave

Definition at line 157 of file Sigma2qqbar2lStarlBar.cxx.

openFracNeg

double Pythia8::Sigma2qqbar2lStarlBar::openFracNeg

Definition at line 158 of file Sigma2qqbar2lStarlBar.cxx.

openFracPos

double Pythia8::Sigma2qqbar2lStarlBar::openFracPos

Definition at line 158 of file Sigma2qqbar2lStarlBar.cxx.

preFac

double Pythia8::Sigma2qqbar2lStarlBar::preFac

Definition at line 158 of file Sigma2qqbar2lStarlBar.cxx.

sigma

double Pythia8::Sigma2qqbar2lStarlBar::sigma

Definition at line 158 of file Sigma2qqbar2lStarlBar.cxx.

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The documentation for this class was generated from the following file:

• Sigma2qqbar2lStarlBar.cxx