EvtMParticle.cpp

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#include "EvtGenBase/EvtMParticle.hh"

#include "EvtGenBase/EvtPatches.hh"
#include "EvtGenBase/EvtSpinType.hh"

EvtMParticle::EvtMParticle( int label, const EvtId& id )
{
    _id = id;
    _twospin = EvtSpinType::getSpin2( EvtPDL::getSpinType( id ) );
    _resonance.push_back( label );
}

EvtSpinAmp EvtMParticle::amplitude( const vector<EvtVector4R>& /*product*/ ) const
{
    vector<EvtSpinType::spintype> types( 2, getspintype() );
    EvtSpinAmp amp( types, EvtComplex( 0.0, 0.0 ) );

    for ( int i = -_twospin; i <= _twospin; i += 2 )
        amp( i, i ) = EvtComplex( 1.0, 0.0 );

    return amp;
}

EvtMNode* EvtMParticle::duplicate() const
{
    return new EvtMParticle( _resonance[0], _id );
}