AliKFParticle::SetField(fESD1->GetMagneticField());
AliKFParticle kfTrack1(*track1, pdg1);
AliKFParticle kfTrack2(*track2, pdg2);
AliKFParticle::SetField(fESD1->GetMagneticField());
AliKFParticle kfTrack1(*track1, pdg1);
AliKFParticle kfTrack2(*track2, pdg2);