EvtbTosllBall.cpp

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#include "EvtGenModels/EvtbTosllBall.hh"
 
#include "EvtGenBase/EvtGenKine.hh"
#include "EvtGenBase/EvtPDL.hh"
#include "EvtGenBase/EvtParticle.hh"
#include "EvtGenBase/EvtReport.hh"
 
#include "EvtGenModels/EvtbTosllAmp.hh"
#include "EvtGenModels/EvtbTosllBallFF.hh"
#include "EvtGenModels/EvtbTosllScalarAmp.hh"
#include "EvtGenModels/EvtbTosllVectorAmp.hh"
 
#include <stdlib.h>
#include <string>
using std::endl;
 
std::string EvtbTosllBall::getName() const
{
    return "BTOSLLBALL";
}
 
EvtDecayBase* EvtbTosllBall::clone() const
{
    return new EvtbTosllBall;
}
 
void EvtbTosllBall::decay( EvtParticle* p )
{
    setWeight( p->initializePhaseSpace( getNDaug(), getDaugs(), false,
                                        m_poleSize, 1, 2 ) );
 
    m_calcamp->CalcAmp( p, m_amp2, m_ballffmodel.get() );
}
 
void EvtbTosllBall::initProbMax()
{
    EvtId parnum, mesnum, l1num, l2num;
 
    parnum = getParentId();
    mesnum = getDaug( 0 );
    l1num = getDaug( 1 );
    l2num = getDaug( 2 );
 
    //This routine sets the m_poleSize.
    double mymaxprob = m_calcamp->CalcMaxProb( parnum, mesnum, l1num, l2num,
                                               m_ballffmodel.get(), m_poleSize );
 
    setProbMax( mymaxprob );
}
 
void EvtbTosllBall::init()
{
    // First choose form factors from the .DEC file
    // 1 = Ali-Ball '01 LCSR
    // 2 = Ali-Ball '99 LCSR
    // 3 = Colangelo 3pt QCD
    // 4 = Melikhov Lattice/Quark dispersion
    // 5 = ???
    // 6 = Ball-Zwicky '05 LCSR (mb = 480)
    // 7 = Ball-Zwicky '05 LCSR (mb = 460 - pseudoscalar modes only)
 
    // The default is Ali '01
    int theFormFactorModel = 1;
 
    if ( getNArg() == 1 )
        theFormFactorModel = (int)getArg( 0 );
 
    checkNDaug( 3 );
 
    //We expect the parent to be a scalar
    //and the daughters to be X lepton+ lepton-
 
    checkSpinParent( EvtSpinType::SCALAR );
 
    EvtSpinType::spintype mesontype = EvtPDL::getSpinType( getDaug( 0 ) );
 
    if ( !( mesontype == EvtSpinType::VECTOR ||
            mesontype == EvtSpinType::SCALAR ) ) {
        EvtGenReport( EVTGEN_ERROR, "EvtGen" )
            << "EvtbTosllBall generator expected "
            << " a SCALAR or VECTOR 1st daughter, found:"
            << EvtPDL::name( getDaug( 0 ) ).c_str() << endl;
        EvtGenReport( EVTGEN_ERROR, "EvtGen" )
            << "Will terminate execution!" << endl;
        ::abort();
    }
 
    checkSpinDaughter( 1, EvtSpinType::DIRAC );
    checkSpinDaughter( 2, EvtSpinType::DIRAC );
 
    m_ballffmodel = std::make_unique<EvtbTosllBallFF>( theFormFactorModel );
    if ( mesontype == EvtSpinType::SCALAR ) {
        m_calcamp = std::make_unique<EvtbTosllScalarAmp>();
    } else if ( mesontype == EvtSpinType::VECTOR ) {
        m_calcamp = std::make_unique<EvtbTosllVectorAmp>();
    }
}