EvtTauVectornu.cpp

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#include "EvtGenModels/EvtTauVectornu.hh"

#include "EvtGenBase/EvtDiracSpinor.hh"
#include "EvtGenBase/EvtGenKine.hh"
#include "EvtGenBase/EvtPDL.hh"
#include "EvtGenBase/EvtParticle.hh"
#include "EvtGenBase/EvtPatches.hh"
#include "EvtGenBase/EvtReport.hh"
#include "EvtGenBase/EvtVector4C.hh"

#include <iostream>
#include <stdlib.h>
#include <string>

std::string EvtTauVectornu::getName()
{
    return "TAUVECTORNU";
}

EvtDecayBase* EvtTauVectornu::clone()
{
    return new EvtTauVectornu;
}

void EvtTauVectornu::init()
{
    // check that there are 0 arguments
    checkNArg( 0 );
    checkNDaug( 2 );

    checkSpinParent( EvtSpinType::DIRAC );

    checkSpinDaughter( 0, EvtSpinType::VECTOR );
    checkSpinDaughter( 1, EvtSpinType::NEUTRINO );
}

void EvtTauVectornu::initProbMax()
{
    setProbMax( 55.0 );
}

void EvtTauVectornu::decay( EvtParticle* p )
{
    static EvtId TAUM = EvtPDL::getId( "tau-" );
    p->initializePhaseSpace( getNDaug(), getDaugs() );

    EvtParticle *v, *nut;
    v = p->getDaug( 0 );
    nut = p->getDaug( 1 );
    double mvec = v->mass();
    EvtVector4C tau1, tau2;

    if ( p->getId() == TAUM ) {
        tau1 = EvtLeptonVACurrent( nut->spParentNeutrino(), p->sp( 0 ) );
        tau2 = EvtLeptonVACurrent( nut->spParentNeutrino(), p->sp( 1 ) );
    } else {
        tau1 = EvtLeptonVACurrent( p->sp( 0 ), nut->spParentNeutrino() );
        tau2 = EvtLeptonVACurrent( p->sp( 1 ), nut->spParentNeutrino() );
    }

    double norm = mvec * sqrt( mvec );

    vertex( 0, 0, norm * tau1 * ( v->epsParent( 0 ).conj() ) );
    vertex( 0, 1, norm * tau1 * ( v->epsParent( 1 ).conj() ) );
    vertex( 0, 2, norm * tau1 * ( v->epsParent( 2 ).conj() ) );
    vertex( 1, 0, norm * tau2 * ( v->epsParent( 0 ).conj() ) );
    vertex( 1, 1, norm * tau2 * ( v->epsParent( 1 ).conj() ) );
    vertex( 1, 2, norm * tau2 * ( v->epsParent( 2 ).conj() ) );

    return;
}