ActsTrk::HGTDTrackExtensionAlg::TrackExtensionData Node1 ActsTrk::HGTDTrackExtension Alg::TrackExtensionData + extrapX + extrapY + extrapZ + numHGTDHits Node2 std::vector< float > + elements Node2->Node1 +chi2Vec +timeVec +rawTimeVec Node3 std::vector< bool > + elements Node3->Node1 +hasClusterVec