Support creation of artdaq input source for combining serialized art Events
Mu2e has a system design where the Tracker and Calorimeter detectors' data is filtered and then selected events are combined with relevant data from the CRV detector. The implementation is to have art jobs performing the filtering in the context of an artdaq EventBuilder, which would then send selected art::Events to a second layer of artdaq EventBuilder which would in turn request the correct data from the CRV artdaq BoardReader. The Fragments from the CRV and the serialized art Event from the Tracker/Calorimeter would then need to be combined in the art input source for this second-level EventBuilder. There is also the possibility of the CRV data passing through its own filter for zero suppression or track-finding, which would entail combining two art events serialized into artdaq Fragments.
If we are able to design and implement such an input source with the general functionality of creating art Events from zero or more Fragments and zero or more serialized art Events, this would be the only art input source artdaq would need. We would like assistance with this design and implementation, as it certainly will have to deal with several of the art internals that we have tripped over in the past.