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JETM12 changes to include pflow b-tagging and electron channel

Hi,

This merge request concerns a variety of updates to JETM12. JETM12 is the derivation for E/p at higher momentum and the updates concern primarily b-tagging updates and ttbar selection. The W->tau+nu and muon control selections are unchanged other than the incorporation of sin(theta) to the vertex selections.

The previous skimming for a ttbar selection was based on EMTopo jets and 201810.MV2c10 b-tagging. This has now been updated to PFlow jets and DL1r which is the recommended tagger. Additionally previous versions had tracking cuts that could induce biases which have been replaced with cuts on reconstructed leptons - this has been fixed. Finally, semi-leptonic ttbar with electrons (rather than just muons) is added to the derivation.

Note that running the b-tagging on PFlow jets is computationally expensive so there are a few additional technical changes to ensure that this operation is run after some selections rather than on all events. (This is done through having multiple Skimming tools and multiple Kernels.). With this the CPU/event is dominated by AODfix (as is the case with most derivations) such that this is fine.

Obviously the addition of the electron channel and removal of cuts that cause biases increase the size of the derivation. The new size has been tested on data from Run 363710 from 2018 with ~45. The fraction of the xAOD size is 0.3% - well below the recommended 1% of the xAOD size.

Cheers, Chris.

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