EvtSll.cpp

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#include "EvtGenModels/EvtSll.hh"
 
#include "EvtGenBase/EvtDiracSpinor.hh"
#include "EvtGenBase/EvtGenKine.hh"
#include "EvtGenBase/EvtPDL.hh"
#include "EvtGenBase/EvtParticle.hh"
#include "EvtGenBase/EvtReport.hh"
#include "EvtGenBase/EvtVector4C.hh"
 
#include <iostream>
#include <stdlib.h>
#include <string>
 
std::string EvtSll::getName() const
{
    return "SLL";
}
 
EvtDecayBase* EvtSll::clone() const
{
    return new EvtSll;
}
 
void EvtSll::init()
{
    // check that there are 0 arguments
    checkNArg( 0 );
    checkNDaug( 2 );
 
    checkSpinParent( EvtSpinType::SCALAR );
 
    checkSpinDaughter( 0, EvtSpinType::DIRAC );
    checkSpinDaughter( 1, EvtSpinType::DIRAC );
}
 
void EvtSll::initProbMax()
{
    const int eID = abs( EvtPDL::getStdHep( EvtPDL::getId( "e-" ) ) );
    const int muID = abs( EvtPDL::getStdHep( EvtPDL::getId( "mu-" ) ) );
    const int tauID = abs( EvtPDL::getStdHep( EvtPDL::getId( "tau-" ) ) );
 
    const int lep1 = abs( EvtPDL::getStdHep( getDaug( 0 ) ) );
    const int lep2 = abs( EvtPDL::getStdHep( getDaug( 1 ) ) );
 
    // tau tau mode
    double maxProb{ 1000.0 };
 
    // Modify probability based on lepton pair (including lepton violation modes)
    if ( ( lep1 == tauID && lep2 == muID ) || ( lep1 == muID && lep2 == tauID ) ) {
        // tau mu or mu tau
        maxProb = 400.0;
    } else if ( ( lep1 == tauID && lep2 == eID ) ||
                ( lep1 == eID && lep2 == tauID ) ) {
        // tau e or e tau
        maxProb = 400.0;
    } else if ( lep1 == muID && lep2 == muID ) {
        // mu mu
        maxProb = 4.0;
    } else if ( ( lep1 == muID && lep2 == eID ) ||
                ( lep1 == eID && lep2 == muID ) ) {
        // mu e or e mu
        maxProb = 2.0;
    } else if ( lep1 == eID && lep2 == eID ) {
        // e e
        maxProb = 1e-4;
    }
 
    setProbMax( maxProb );
}
 
void EvtSll::decay( EvtParticle* p )
{
    p->initializePhaseSpace( getNDaug(), getDaugs() );
 
    EvtParticle *l1, *l2;
    l1 = p->getDaug( 0 );
    l2 = p->getDaug( 1 );
    EvtVector4R p4_p;
    p4_p.set( p->mass(), 0.0, 0.0, 0.0 );
 
    EvtVector4C l11, l12, l21, l22;
 
    l11 = EvtLeptonVACurrent( l1->spParent( 0 ), l2->spParent( 0 ) );
    l12 = EvtLeptonVACurrent( l1->spParent( 0 ), l2->spParent( 1 ) );
    l21 = EvtLeptonVACurrent( l1->spParent( 1 ), l2->spParent( 0 ) );
    l22 = EvtLeptonVACurrent( l1->spParent( 1 ), l2->spParent( 1 ) );
 
    vertex( 0, 0, p4_p * l11 );
    vertex( 0, 1, p4_p * l12 );
    vertex( 1, 0, p4_p * l21 );
    vertex( 1, 1, p4_p * l22 );
 
    return;
}