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Update calorimeter spatial alignment (w.r.t trackers)

Maarten Van Veghel requested to merge mveghel-caloalignment into offline

Updating alignment conditions (for all (current) Run 3)

  • /Conditions/Ecal/Alignment.yml/0
  • /Conditions/Hcal/Alignment.yml/0

Relies on lhcb/Detector!478 (merged)

Closes lhcb/Alignment#100 (closed), see also slides from RTA WP4 here and older ones here

Derivation using electron CaloHypo position on early 2024 data (run 289526) and MC as cross-check / comparison, and using cluster corrections from !119 (merged). Track extrapolation is performed to z of associated CaloHypo in an (essentially min bias) electron sample (mostly converted photons). Allowing for a floating bias in z yields same results in x / y. Optimization is performed using PyTorch with a loss function equivalent to a \chi^{2}, target values are x / y positions of associated CaloHypo. The x position of the tracks allows for degrees of freedom for momentum dependent correction as in https://gitlab.cern.ch/lhcb/Rec/-/blob/master/CaloFuture/CaloFuturePIDs/src/SelectiveElectronMatchAlg.cpp#L250. Assumes Hcal alignment is 100% correlated with Ecal.

For future runs in master see !137 (merged)

Edited by Maarten Van Veghel

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