double Mixing_Handler::DetermineMixingTime(Particle* decayer,
bool checkforpartstatus) const
{
double time = decayer->Time();
Blob* motherblob = decayer->ProductionBlob();
if(motherblob->Type()==btp::Hadron_Mixing) {
decayer = motherblob->InParticle(0);
motherblob = decayer->ProductionBlob();
}
Particle* sister = NULL;
if(motherblob->Type()!=btp::Fragmentation ||
(motherblob->NInP()==2 && motherblob->NOutP()==2 &&
motherblob->InParticle(0)->Flav()==motherblob->OutParticle(0)->Flav() &&
motherblob->InParticle(1)->Flav()==motherblob->OutParticle(1)->Flav())) {
// check if particle was produced coherently
Particle_Vector sisters = motherblob->GetOutParticles();
for(Particle_Vector::const_iterator it=sisters.begin(); it!=sisters.end(); it++) {
if((*it)!=decayer && decayer->Flav()==(*it)->Flav().Bar()) {
sister = (*it);
break;
}
}
}
// in coherent production, special rules apply:
if(sister) {
if((checkforpartstatus && sister->Status()==part_status::decayed) ||
(!checkforpartstatus && sister->DecayBlob()))
{
time = time - sister->Time();
}
else time = 0.0;
}
return time;
}
void Hadron_Decay_Handler::SetPosition(ATOOLS::Blob* blob)
{
Particle* inpart = blob->InParticle(0);
if(inpart->Flav().Kfcode()==kf_K) {
blob->SetPosition(inpart->XProd());
return;
}
// boost lifetime into lab
double gamma = 1./rpa->gen.Accu();
if (inpart->Flav().HadMass()>rpa->gen.Accu()) {
gamma = inpart->E()/inpart->Flav().HadMass();
}
else {
double q2 = dabs(inpart->Momentum().Abs2());
if (q2>rpa->gen.Accu()) gamma = inpart->E()/sqrt(q2);
}
double lifetime_boosted = gamma * inpart->Time();
Vec3D spatial = inpart->Distance( lifetime_boosted );
Vec4D position = Vec4D( lifetime_boosted*rpa->c(), spatial );
blob->SetPosition( inpart->XProd() + position ); // in mm
}
