EvtSTSCP.cpp

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#include "EvtGenModels/EvtSTSCP.hh"
 
#include "EvtGenBase/EvtCPUtil.hh"
#include "EvtGenBase/EvtConst.hh"
#include "EvtGenBase/EvtGenKine.hh"
#include "EvtGenBase/EvtId.hh"
#include "EvtGenBase/EvtPDL.hh"
#include "EvtGenBase/EvtParticle.hh"
#include "EvtGenBase/EvtReport.hh"
#include "EvtGenBase/EvtTensor4C.hh"
#include "EvtGenBase/EvtVector4C.hh"
 
#include <stdlib.h>
#include <string>
 
std::string EvtSTSCP::getName() const
{
    return "STS_CP";
}
 
void EvtSTSCP::initProbMax()
{
    //This is probably not quite right, but it should do as a start...
    //Anders
 
    setProbMax( 20 * ( getArg( 3 ) * getArg( 3 ) + getArg( 5 ) * getArg( 5 ) ) );
}
 
EvtDecayBase* EvtSTSCP::clone() const
{
    return new EvtSTSCP;
}
 
void EvtSTSCP::init()
{
    // check that there are 7 arguments
    checkNArg( 7 );
    checkNDaug( 2 );
 
    checkSpinParent( EvtSpinType::SCALAR );
 
    checkSpinDaughter( 0, EvtSpinType::TENSOR );
    checkSpinDaughter( 1, EvtSpinType::SCALAR );
}
 
void EvtSTSCP::decay( EvtParticle* p )
{
    //added by Lange Jan4,2000
    static const EvtId B0 = EvtPDL::getId( "B0" );
    static const EvtId B0B = EvtPDL::getId( "anti-B0" );
 
    double t;
    EvtId other_b;
 
    EvtParticle* t1;
    p->initializePhaseSpace( getNDaug(), getDaugs() );
    t1 = p->getDaug( 0 );
    EvtVector4R momt = t1->getP4();
    EvtVector4R moms = p->getDaug( 1 )->getP4();
    double masst = t1->mass();
 
    EvtCPUtil::getInstance()->OtherB( p, t, other_b, 0.5 );
 
    EvtComplex amp;
 
    EvtComplex A, Abar;
 
    A = EvtComplex( getArg( 3 ) * cos( getArg( 4 ) ),
                    getArg( 3 ) * sin( getArg( 4 ) ) );
    Abar = EvtComplex( getArg( 5 ) * cos( getArg( 6 ) ),
                       getArg( 5 ) * sin( getArg( 6 ) ) );
 
    if ( other_b == B0B ) {
        amp = A * cos( getArg( 1 ) * t / ( 2 * EvtConst::c ) ) +
              EvtComplex( cos( -2.0 * getArg( 0 ) ), sin( -2.0 * getArg( 0 ) ) ) *
                  getArg( 2 ) * EvtComplex( 0.0, 1.0 ) * Abar *
                  sin( getArg( 1 ) * t / ( 2 * EvtConst::c ) );
    }
    if ( other_b == B0 ) {
        amp = A * EvtComplex( cos( 2.0 * getArg( 0 ) ), sin( 2.0 * getArg( 0 ) ) ) *
                  EvtComplex( 0.0, 1.0 ) *
                  sin( getArg( 1 ) * t / ( 2 * EvtConst::c ) ) +
              getArg( 2 ) * Abar * cos( getArg( 1 ) * t / ( 2 * EvtConst::c ) );
    }
 
    EvtVector4R p4_parent;
 
    p4_parent = momt + moms;
 
    double norm = masst * masst / ( p->mass() * momt.d3mag() * momt.d3mag() );
 
    vertex( 0, amp * norm * t1->epsTensorParent( 0 ).cont1( p4_parent ) *
                   p4_parent );
    vertex( 1, amp * norm * t1->epsTensorParent( 1 ).cont1( p4_parent ) *
                   p4_parent );
    vertex( 2, amp * norm * t1->epsTensorParent( 2 ).cont1( p4_parent ) *
                   p4_parent );
    vertex( 3, amp * norm * t1->epsTensorParent( 3 ).cont1( p4_parent ) *
                   p4_parent );
    vertex( 4, amp * norm * t1->epsTensorParent( 4 ).cont1( p4_parent ) *
                   p4_parent );
 
    return;
}
 
std::string EvtSTSCP::getParamName( int i )
{
    switch ( i ) {
        case 0:
            return "weakPhase";
        case 1:
            return "deltaM";
        case 2:
            return "finalStateCP";
        case 3:
            return "Af";
        case 4:
            return "AfPhase";
        case 5:
            return "Abarf";
        case 6:
            return "AbarfPhase";
        default:
            return "";
    }
}
 
std::string EvtSTSCP::getParamDefault( int i )
{
    switch ( i ) {
        case 3:
            return "1.0";
        case 4:
            return "0.0";
        case 5:
            return "1.0";
        case 6:
            return "0.0";
        default:
            return "";
    }
}