EvtRareLbToLllFFBase.cpp

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#include "EvtGenModels/EvtRareLbToLllFFBase.hh"
 
EvtRareLbToLllFFBase::FormFactors::FormFactors()
{
    areZero();
}
 
void EvtRareLbToLllFFBase::FormFactors::areZero()
{
    for ( unsigned int i = 0; i < 4; ++i ) {
        m_F[i] = 0;
        m_G[i] = 0;
        m_FT[i] = 0;
        m_GT[i] = 0;
    }
}
 
EvtRareLbToLllFFBase::EvtRareLbToLllFFBase() :
    m_natural{ "Lambda0",       "anti-Lambda0",
               "Lambda(1520)0", "anti-Lambda(1520)0",
               "Lambda(1600)0", "anti-Lambda(1600)0" }
{
}
 
bool EvtRareLbToLllFFBase::isNatural( const EvtParticle& lambda ) const
{
    return m_natural.contains( lambda.getId() );
}
 
double EvtRareLbToLllFFBase::calculateVdotV( const EvtParticle& parent,
                                             const EvtParticle& lambda ) const
{
    EvtVector4R p4parent;
    p4parent.set( parent.mass(), 0, 0, 0 );
 
    EvtVector4R p4lambda = lambda.getP4();
 
    const double M = lambda.mass();
    const double MB = parent.mass();
 
    return p4parent.cont( p4lambda ) / ( MB * M );
 
    // return E_Lambda/M_Lambda
}
 
double EvtRareLbToLllFFBase::calculateVdotV( const EvtParticle& parent,
                                             const EvtParticle& lambda,
                                             const double qsq ) const
{
    const double M = lambda.mass();
    const double MB = parent.mass();
 
    double E = ( MB * MB - M * M - qsq ) / ( 2. * MB );
 
    return E / M;
}