AFT-673: Copy Run 3 Online xAOD::BTagging Content to Jets
Before Run 4, we historically use BTagging objects associated with online jets to store b-tagging information. From Run 4 onward, we use online jets to store b-tagging information directly. Therefore, we need to copy the b-tagging information from BTagging objects to online jets, so that the downstream algorithms can access the b-tagging information from jets directly.
Offline b-tagging information has been all stored in jets for reprocessed Run 2 DAOD, so no copying is needed for offline jets.
Run 3 containers that need to be copied:
HLT_AntiKt4EMPFlowJets_subresjesgscIS_ftf_BTagging -> HLT_AntiKt4EMPFlowJets_subresjesgscIS_ftf_bJets
HLT_AntiKt4EMTopoJets_subresjesgscIS_ftf_BTagging -> HLT_AntiKt4EMTopoJets_subresjesgscIS_ftf_bJets
HLT_AntiKt4EMPFlowJets_subresjesgscIS_ftf_TLA_BTagging -> HLT_AntiKt4EMPFlowJets_subresjesgscIS_ftf_TLA
Run 2 containers that need to be copied:
HLT_xAOD__BTaggingContainer_HLTBjetFex -> HLT_xAOD__JetContainer_SplitJet, HLT_xAOD__JetContainer_GSCJet, HLT_xAOD__JetContainer_EFJet
NOTE: This implementation only supports Run 3. Please see https://its.cern.ch/jira/browse/ATR-26904, links from BTagging to jet are broken for both Run 2 and Run 3 data. We can only do index matching since link navigation is unavailable. For Run 2 Data, both index matching and link navigation are unavailable since the BTagging objects point to multiple jet containers.
Run 2 MC copying has been verified working in a previous commit, but for consistency we disable the copying for Run 2 data and MC.
TODO: Figure out a way to support Run 2 data in future if needed. More discussion can be found in https://its.cern.ch/jira/browse/ATR-26904