Replace the QEE Inclusive HNL Line with a New Version Triggering on T-track Vertex Only

The merge request implements a new QEE inclusive T-track line which reconstructs an N -> pi+ mu- vertex (with N some high mass, neutral particle such as a Heavy Neutral Lepton or HNL). This replaces the existing HNL selections BtoMuN_MuPi_InclTT and BtoEN_MuPi_InclTT, whilst:

Having greatly improved sensitivity for HNLs(click to expand)

Attached are the projected number of selected `B_q -> [X] mu (N -> mu pi)` events using the old and new selection assuming 10 inverse femtobarn. Assuming no background, the red contour of 3 events reflects the 95% rejection contour that could be placed with a full analysis. [N.B. the new selection has been retuned since the production of these plots, improving its sensitivity by a further factor of 2]NewSelection.pdf OldSelection.pdf

Having greatly improved flexibility for both HNLs and other long-lived particles (click to expand)

The new line both persists the detector rawbanks and the long tracks passing ISMUON. This allows us to conduct an analysis with exclusive lings muon-flavour-coupled HNLs without a dedicated sprucing line, whilst also being able rerun the reconstruction to: - Add more tracks needed for searches for other long lived BSM particles which could be triggered by the general `N -> mu pi` vertex signal - Add more tracks for HNLs. This could be required/desirable due to a redevelopment of HNL theory, novel analysis techniques, or to search for HNL-lepton couplings which are not purely muonic. - Evaluate T-track tracking efficiencies for MC-data corrections. - Implement and test improvements in T-track reconstruction - Rule out detector effects in the case of a positive signal for HNLs or other BSM particles

Due to the novel approach of persisting the whole rawbank, this flexibility is acquired at 1/3 the bandwidth of a fullstream line.

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The bandwidth (BW) effect were estimated over a sample of 100,000 minbias events following the QEE BW testing guidelines.

We find an expected bandwidth change of

QEE Turbo BW: +7.1 MB/s

This is more than offset by the retune of the long and downstream HNL lines (now merged) in Moore!4481

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Further details on the physics impact can be found at the QEE WG meeting (here), or in the comment chains below